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  • 1.
    Abbas, Nahla
    et al.
    School of Engineering and Technology, Central Queensland University, Australia.
    Wasimi, Saleh A.
    School of Engineering and Technology, Central Queensland University, Australia.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Impacts of Climate Change on Water Resources in Diyala River Basin, Iraq2016Inngår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 10, nr 9, s. 1059-1074Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Diyala River is the third largest tributary of the Tigris River running 445 km length and draining an area of 32,600 km2. The river is the major source of water supply for Diyala City for municipal, domestic, agriculture and other purposes. Diyala River Basin currently is suffering from water scarcity and contamination problems. Up-to-date studies have shown that blue and green waters of a basin have been demonstrating increasing variability contributing to more severe droughts and floods seemingly due to climate change. To obtain better understanding of the impacts of climate change on water resources in Diyala River Basin in near 2046~2064 and distant future 2080~2100, SWAT (soil and water assessment tool) was used. The model is first examined for its capability of capturing the basin characteristics, and then, projections from six GCMs (general circulation models) are incorporated  to assess the impacts of climate change on water resources under three emission scenarios: A2, A1B and B1. The results showed deteriorating water resources regime into the future.

  • 2.
    Abbas, Nahlah
    et al.
    School of Engineering & Technology, Central Queensland University, Melbourne, Australia.
    Wasimia, Saleh A.
    School of Engineering & Technology, Central Queensland University, Melbourne, Australia.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Assessment of Climate Change Impact on Water Resources of Lesser Zab, Kurdistan, Iraq Using SWAT Model2016Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, s. 697-715Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Kurdistan in northern Iraq, a semi-arid region, predominantly a pastureland, is nourished by Lesser Zab, which is the second major tributary of Tigris River. The discharge in the tributary, in recent times, has been experiencing increasing variability contributing to more severe droughts and floods supposedly due to climate change. For a proper appreciation, SWAT model has been used to assess the impact of climate change on its hydrological components for a half-centennial lead time to 2046-2064 and a centennial lead time to 2080-2100. The suitability of the model was first evaluated, and then, outputs from six GCMs were incorporated to evaluate the impacts of climate change on water resources under three emission scenarios: A1B, A2 and B1. The results showed worsening water resources regime.

  • 3.
    Abbas, Nahlah
    et al.
    School of Engineering & Techno logy, Central Queensland Univ ersity, Melbourne, Australia .
    Wasimia, Saleh A.
    School of Engineering & Techno logy, Central Queensland Univ ersity, Melbourne, Australia .
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Assessment of Climate Change Impacts on Water Resources of Al-Adhaim, Iraq Using SWAT Model2016Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, s. 716-732Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    SWAT model (Sediment and Water Assessment Tool) was used to evaluate the impacts of climate change on water resources in Al-Adhaim Basin which is located in north east of Iraq. Al-Adhaim River is the main source of fresh water to Kirkuk City, one of the largest cities of Iraq. Recent studies have shown that blue and green waters of the basin have been manifesting increasing variability contributing to more severe droughts and floods apparently due to climate change. In order to gain greater appreciation of the impacts of climate change on water resources in the study area in near and distant future, SWAT (Soil and Water Assessment Tool) has been used. The model is first tested for its suitability in capturing the basin characteristics, and then, forecasts from six GCMs with about half-a-century lead time to 2046-2064 and one-century lead time to 2080-2100 are incorporated to evaluate the impacts of climate change on water resources under three emission scenarios: A2, A1B and B1. The results showed worsening water resources regime into the future.

  • 4.
    Abbas, Nahlah
    et al.
    School of Engineering & Technology Central Queensland University, Melbourne, Australia.
    Wasimia, Saleh A.
    School of Engineering & Technology Central Queensland University, Melbourne, Australia.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Assessment of climate change impacts on water resources of Khabour in Kurdistan , Iraq using SWAT model2016Inngår i: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 24, s. 1-21, artikkel-id 10Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Khabour River is one of five tributaries of Tigris River and the first river flows into Tigris River contributing to Tigris Flow by about 2 BCM at Zakho Station. The area of this catchment is 6,143 km2, of which 57% are located in Turkey and 43% in Iraq with a total length of 181 km. Khabour River is the main source of fresh water to Duhok City, one of the major cities of Kurdistan Region. Hydrometeorological data over the past several decades reveal that the catchment is experiencing increasing variability in precipitation and stream flow contributing to more severe droughts and floods presumably due to climate change. SWAT model was applied to capture the dynamics of the basin. The model was calibrated at Zakho station. The performance of the model was rather satisfactory; R2 and ENC were 0.5 and 0.51, respectively in calibration period. In validation process R2 and ENC were nearly consistent. In the next stage, six GCMs from CMIP3 namely, CGCM3.1/T47, CNRM-CM3, GFDL-CM2.1, IPSLCM4, MIROC3.2 (medres) and MRI CGCM2.3.2 were selected for climate change projections in the basin under a very high emissions scenario (A2), a medium emissions scenario (A1B) and a low emissions scenario (B1) for two future periods (2046-2064) and (2080-2100). All GCMs showed consistent increases in temperature and decreases in precipitation, and as expected, highest rate for A2 and lowest rate for B1. The projected temperatures and precipitation were input to the SWAT model to project water resources, and the model outputs were compared with the baseline period (1980-2010), the picture that emerged depicted deteriorating water resources variability.

  • 5.
    Achleitner, Stefan
    et al.
    Unit of Hydraulic Engineering, University of Innsbruck.
    Schröber, Johannes
    AlpS - Centre for Climate Change Adaptation Technologies, Innsbruck.
    Rinderer, Michael
    Hydrology and Climate Unit, Department of Geography, University of Zurich.
    Leonhardt, Günther
    Unit of Environmental Engineering, University of Innsbruck.
    Schöberl, Friedrich
    Institute of Geography, University of Innsbruck.
    Kirnbauer, Robert
    Institute of Hydraulic Engineering and Water Resources Management, Vienna University of Technology.
    Schönlaub, Helmut
    TIWAG - Tiroler Wasserkraft AG.
    Analyzing the operational performance of the hydrological models in an alpine flood forecasting system2012Inngår i: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 412-413, s. 90-100Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    During recent years a hybrid model has been set up for the operational forecasting of flood discharges in the 6750km 2 Tyrolean part of the River Inn catchment in Austria. The catchment can be characterized as a typical alpine area with large variations in altitude. The paper is focused on the error analysis of discharge forecasts of four main tributary catchments simulated with hydrological water balance models. The selected catchments cover an area of 2230km 2, where the non-glaciated and glaciated parts are modeled using the semi-distributed HQsim and the distributed model SES, respectively.The forecast errors are evaluated as a function of forecast lead time and forecasted discharge magnitude using 14 events from 2007 to 2010. The observed and forecasted precipitation inputs were obtained under operational conditions. The mean relative bias of the forecasted discharges revealed to be constant with regard to the forecast lead time, varying between 0.2 and 0.25 for the different catchments. The errors as a function of the forecasted discharge magnitude showed large errors at lower values of the forecast hydrographs, where errors decreased significantly at larger discharges being relevant in flood forecasting

  • 6.
    Addie, G.R.
    et al.
    GIW Industries Inc..
    Roudnev, A.S.
    Weir Minerals North America.
    Sellgren, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Weir Minerals North America2007Inngår i: Hydrotransport 17: the 17th International Conference on the Hydraulic Transport of Solids ; [7 - 11 May 2007, Cape Town, South Africa, South African Institute of Mining and Metallurgy, 2007, s. 205-218Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The Hydraulic Institute has completed the task of developing a new ANSI/HI standard 12.1-12.6 (2005) for rotodynamic (centrifugal) slurry pumps covering nomenclature, definitions, applications, and operation. The standard provides examples of the different slurry pump types and contains an extensive section on pump and slurry definitions. The effect of slurry on pump performance is covered along with the pumping of froth. Reference is also made to ANSI/HI standard 9.6.7 (2004), which contains a new method for pump performance correction when handling viscous fluids. Classification of slurry services is established and then is used to determine limitations on velocities and total head per pump in order to obtain acceptable wear performance. The new service class, head per stage and other limits are directly related to capital and other cost considerations that will affect solids transport system economics. The writers review the contents of the new standard, highlight the main points, and discuss the reason for the slurry classification, corresponding limits and expected implications, particularly with respect to operating costs of the pumps in solids transport systems

  • 7.
    Addie, Graeme
    et al.
    Engineering and Research and Development, GIW Industries Inc.
    Carstens, M.
    GIW Industries Inc..
    Sellgren, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Visintainer, R.
    GIW Industries Inc..
    Whitlock, L
    Hydraulic Test Lab., GIW Industries Inc.
    Pipeline design characteristics of some industrial paste-like slurries2005Inngår i: Conference Proceedings - First Extractive Metallurgy Operators' Conference, The Australian Institute of Mining and Metallurgy , 2005, s. 147-154Konferansepaper (Fagfellevurdert)
    Abstract [en]

    There is a wide variety of industrial pastes or non-settling slurries pumped in mining, dredging and reclamation projects as products, refuse and tails. The types and/or names of some of the common ones are alumina red mud, phosphate clays, tar sands mature fine tails, tar sands (CT) consolidated clays and fly ash. The pipeline performance or friction of these varies dramatically with the type, its concentration and the particulars of the actual slurry making it difficult to select pumping equipment and to design associated pipelines. The GIW Hydraulic Laboratory in Grovetown Georgia has tested a number of these slurries over the last 30 years for various mining customers. Where available in the public domain and/or where permission has been obtained, the results of those tests are presented in this paper in a form usable for pipeline and pump system designers and users.

  • 8.
    Addie, Graeme R.
    et al.
    GIW Industries Inc..
    Roudnev, Aleksander S.
    Weir Minerals North America.
    Sellgren, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    The new ANSI/HI centrifugal slurry pump standard2007Inngår i: Journal of the South African Institute of Mining and Metallurgy, ISSN 0038-223X, Vol. 107, nr 6, s. 403-409Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Hydraulic Institute has completed the task of developing a new ANSI/HI standard 12.1-12.6 (2005) for Rotodynamic (Centrifugal) Slurry Pumps covering nomenclature, definitions, applications, and operation. The standard provides examples of the different slurry pump types and contains an extensive section on pump and slurry definitions. The effect of slurry on pump performance is covered along with the pumping of froth. Reference is also made to ANSI/HI standard 9.6.7 (2004), which contains a new method for pump performance correction when handling viscous fluids.Classification of slurry services is established and then is used to determine limitations on velocities and total head per pump in order to obtain acceptable wear performance. The new service class, head per stage and other limits are directly related to capital and other cost considerations that will affect solids transport system economics. The writers review the contents of the new standard, highlight the main points, and discuss the reason for the slurry classification, corresponding limits and expected implications, particularly with respect to operating costs of the pumps in solids transport systems.

  • 9.
    Addie, Graeme R.
    et al.
    GIW Industries Inc..
    Sellgren, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    A first slurry standard and some implications for paste application2007Inngår i: Paste 2007: proceedings of the tenth International Seminar on Paste and Thickened Tailings / [ed] Andy Fourie; Richard Jewell, Perth: Australian Centre for Geomechanics, 2007, s. 153-162Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The Hydraulic Institute has just completed the task of developing a new ANSI/HI standard on Rotodynamic (Centrifugal) Slurry Pumps covering nomenclature, definitions, applications, and operation. The standard provides examples of all the different types of pumps available and has an extensive section on definitions. Slurries and their effect on performance and wear are covered. A slurry service class is established which then is used to limit velocities and head produced per pump to give acceptable wear. A special section deals with mechanical seals and a new method for determining flange loads is presented and guidelines are given for commissioning, start-up etc.The head limits and the performance derating are of special interest when centrifugal slurry pumps are applied to thickened tailings and paste-like slurries. For Newtonian liquids, the Hydraulic Institute's Viscosity Correction Method (ANSI/HI 2004) provides a procedure widely used for viscous effects on the performance. For the homogeneous flow of viscous slurries, the new slurry standard refers to an applicable viscosity to use with the method and to "consult the pump manufacturer for guidance regarding non-Newtonian slurry pump performance."Experimental performance results are presented here and applied to the viscosity correction method for a simulated tailings product slurry characterized by a fully sheared yield stress of about 100 Pa, evaluated from pipeline data. The pump was a GIW-LCC type three-vane all metal unit with a 0.3m-diameter impeller having an open shroud with a simple auger-like inducer. Results are also given for an underground hydraulic fill product characterized by a Newtonian kinematic viscosity which is 1300 times that for water. The different results obtained here point out the strong influence the rheological behavior has on the choice of pump size and the power requirement.

  • 10.
    Addle, Graeme R
    et al.
    GIW Industries Inc..
    Sellgren, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Design, selection, sizing and control considerations for cyclone feed slurry pumps1999Inngår i: Powder Technology, ISSN 0032-5910, E-ISSN 1873-328X, Vol. 104, nr 3, s. 233-239Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cyclone feed centrifugal slurry pumps in semi-autogenous grinding (SAG) mill and other cyclone feed circuits see coarse size slurries at high concentrations that can result in high wear if the pump is not designed, selected, sized and operated correctly. The high proportion of static head of the normal cyclone feed circuits usually results in a relatively flat system curve which in conjunction with the typically flat slurry pump curve results in large changes in operating flow with small changes in system head. When this is combined with the normal (or abnormal) fluctuations in the output from the mill upstream of the pumps, any shortcomings in the pump control system and/or matching of the pump means large fluctuations in flow and increased wear. This difficulty could be corrected by continuous variations in speed. A means of control by which the speed is changed in an appropriate way is suggested here. In this case then the pump-input power, the known water performance of the pump and the system flow, can be used to calculate an effective pump discharge pressure. By comparison with a calculated system head, the pump speed can be regulated such that the pressures are equal and the system stable for any practical variation of incoming flow or specific gravity.

  • 11.
    Alere, Ilze
    Luleå tekniska universitet.
    Aspects of water quality dynamics in drinking water distribution systems1997Licentiatavhandling, med artikler (Annet vitenskapelig)
  • 12.
    Alere, Ilze
    et al.
    Luleå tekniska universitet.
    Hanaeus, Jörgen
    Particle dynamics in the drinking water distribution network of Luleå1997Inngår i: Vatten, ISSN 0042-2886, nr 4, s. 381-390Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [sv]

    Partikeldynamik i Luleås dricksvattennät

  • 13.
    Al-Madhlom, Qais
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. College of Engineering/Al-Musaib, University of Babylon, Hillah, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Hussain, Hussain Musa
    Remote Sensing Center, University of Kufa, Kufa, Iraq.
    Site Selection of Aquifer Thermal Energy Storage Systems in Shallow Groundwater Conditions2019Inngår i: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, nr 7, artikkel-id 1393Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Underground thermal energy storage (UTES) systems are widely used around the world, due to their relations to heating ventilating and air conditioning (HVAC) applications [1]. To achieve the required objectives of these systems, the best design of these systems should be accessed first. The process of determining the best design for any UTES system has two stages, the type selection stage and the site selection stage. In the type selection stage, the best sort of UTES system is determined. There are six kinds of UTES systems, they are: boreholes, aquifer, bit, tank, tubes in clay, and cavern [2–5]. The selection of a particular type depends on three groups of parameters. They are: Site specific, design, and operation parameters (Figure 1). Apart from site specific parameters, the other two types can be changed through the life time of the system. The site specific parameters, e.g., geological, hydrogeological, and metrological, cannot be changed during the service period of the  ystem. Therefore, the design of the best type should depend, at first consideration, on site specific parameters.

  • 14.
    Al-Madhlom, Qais
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. University of Babylon, Babylon, Iraq.
    Hamza, B.
    University of Babylon, Babylon, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Hussain, Hussain M.
    Kufa University, Kufa, Iraq.
    Site Selection Criteria of UTES Systems in Hot Climate2019Inngår i: Proceedings of the XVII ECSMGE-2019: Geotechnical Engineering foundation of the future, Iceland: The Icelandic Geotechnical Society (IGS) , 2019, Vol. 1, s. 1-8Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Underground Thermal Energy Storage UTES systems are widely used around the world. The reason is that UTES is essential in utilizing Renewable Energy sources (RE). The efficiency of the energy system relies strongly on the efficiency of the storage system. Therefore, in the installation of a hyper-energy system, a lot of attention is to be paid in improving the storage system. In order to design an efficient storage system, firstly, standard criteria are to be investigated. These explain the process of making high efficiency storage system that must be specified. The criteria, mainly, depends on: best type and best location. These two variables are in high interference with each other. The bond between the two variables is represented by the geological, hydrological, meteorological, soil, hydrogeological properties/factors of the site. These factors are specified by geo-energy mapping. Despite the importance of this type of mapping, there is no specific criteria/formula that defines the choice. This paper aims to: give a brief literature review for UTES systems (types, classification, advantages/disadvantages for each type, and examples of an installed system). In addition, some factors within geo-energy mapping are highlighted and standard criteria to achieve good storage system are suggested. The suggested criterion comprises a process to transfer the quantity values to quality values according to the expert opinion. The suggested criteria are defined through the following stages: selecting the best type of UTES systems according to hydro-geological in site conditions; using the analytical hierarchy process to rank the best location to install the storage system and then using ArcMap (GIS-Software) to provide representative results as maps. Karbala Province (Iraq) is the study area used here

  • 15.
    Al-Madhlom, Qais
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Chabuk, Ali
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. University of Babylon, Babylon, Hilla, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Lindblom, Jenny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    University of Kufa, Kufa, Najaf, Iraq.
    Potential use of UTES in Babylon Governorate, Iraq2020Inngår i: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 10, artikkel-id 100283Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    There is a global attention that the future energy systems will be based on renewable energy like solar and wind. The large-scale utilization of renewables in space heating and cooling requires large Thermal Energy Storage TES to overcome the varying supply and demand. The process of producing the best Underground Thermal Energy Storage UTES system pass through two steps: first, finding the best type of UTES system, second, finding the best locations to install UTES system. Both of these two steps depend extremely on the site specific parameters such that the depth to the groundwater, transmissivity, type of soil, the depth to the bedrock, and seepage velocity. The purpose of this paper is to explain some of the site specific parameters that the type of UTES-system depends on and explain the suitable type of UTES systems. This study considers Babylon province (Iraq) as study area. This province has electricity deficiency due to Heating Ventilating and Air Conditioning HVAC applications. The methodology of this study includes reviewing the literature that consider the study area, and using Arc Map/GIS to visualize some of the in-site parameters. The results indicate that the best type of UTES system for the considered region is either aquifer or pit type, due to the type of the soil and the depth to the crystalline bedrock. The hydraulic conductivity and the seepage velocity in the considered region are (0.0023–2.5) m/d and (1.3 × 10−6 – 3.45 × 10−3) m/d respectively. These conditions satisfy the standards which regard aquifer type.

  • 16.
    Almqvist, Helena
    et al.
    Luleå kommun.
    Hanaeus, Jörgen
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Organic hazardous substances in graywater from Swedish households2006Inngår i: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 132, nr 8, s. 901-908Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The concentrations of several selected organic hazardous substances were investigated in domestic graywater. In total, 41 of 81 organic hazardous substances were found in concentrations above the detection limits (nonylphenol and octylphenol ethoxylates, brominated flame-retardants, organotin compounds, polyaromatic hydrocarbons, polychlorinated biphenyls, phthalates, linear-alkyl benzene sulfonate, and triclosan). Moreover, total solids, biochemical oxygen demand (BOD7), chemical oxygen demand (COD), total nitrogen, total phosphorus, potassium, and sulphur were investigated and presented for graywater. Another objective was to suggest potential household sources for a selected number of organic hazardous substances. The present and past investigations reveal households to be obvious contributors of organic hazardous substances to municipal wastewater, and that graywater is an important media in this transport. The spreading derives from diffuse household sources like everyday activities (laundry, cleaning, etc.), the wearing down of things such as pipe material and interior fittings, and from airborne deposition.

  • 17.
    Al-Rubaei, Ahmed
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Long-Term Performance, Operation and Maintenance Needs of Stormwater Control Measures2016Doktoravhandling, med artikler (Annet vitenskapelig)
  • 18.
    Al-Rubaei, Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Engström, Malin
    Växjö Municipality.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Blecken, Godecke-Tobias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Long-term hydraulic and treatment performance of a 19-year old constructed stormwater wetland: Finally maturated or in need of maintenance?2016Inngår i: Ecological Engineering: The Journal of Ecotechnology, ISSN 0925-8574, E-ISSN 1872-6992, Vol. 95, s. 73-82Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Constructed stormwater wetlands (CSWs) are a commonly used measure for stormwater retention and quality treatment. However, although questions have been raised about the long-term performance of CSWs, only a few studies have targeted this issue and none have evaluated the performance of CSWs more than approximately 5–10 years old. Further, most studies have not examined the development of the long-term performance of CSWs but delivered a snapshot at a certain point of time. The present study investigated the performance of a 19-year-old CSW in Växjö, Sweden, treating stormwater from a 320-ha urban catchment. Besides removal of sediment from the CSW’s forebay, no other maintenance had been conducted. However, regular inspections had been performed. The results of the present sampling campaign were compared to two existing datasets collected at the same CSW after three years of operation in 1997 and nine years of operation in 2003. The CSW was found to provide efficient peak flow reduction and, depending on the event characteristics, also volume reduction. It still treated stormwater effectively: removal of Cd, Cu, Pb, Zn, TSS and TP event mean concentrations were between 89 and 96%, whereas mean concentrations of TN were reduced by 59%. The load removal efficiencies were even higher. Comparative analysis of the three monitoring periods based on the load removal efficiency revealed that the CSW, despite the lack of maintenance, performed more efficiently and stably for most pollutants compared to when newly constructed. This underlines the importance of the establishment and maturation of constructed wetland systems. Overall, the results showed that CSWs are resilient systems, which if designed well and regularly inspected to prevent major issues, can work efficiently for at least two decades.

  • 19.
    Al-Rubaei, Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Engström, Malin
    Växjö Municipality.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Blecken, Godecke-Tobias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Long-term hydraulic performance of stormwater infiltration systems: a field survey2013Inngår i: NOVATECH 2013: Planning and Technologies for Sustainable Urban Water Management, 23 - 27 June 2013, Lyon, France., 2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper examined the factors influencing the long-term hydraulic performance of some stormwater infiltration systems (swale and two types of permeable pavements) in Växjö, southern Sweden. The infiltration capacities of 9 permeable pavements and 2 swales sites, all with different ages ranging from 1 year to 14 years, were measured using replicate double ring infiltrometers. The sites were either constructed of swale (2), interlocking concrete pavers (ICP) filled with gravel (2), concrete grid pavers (CGP) filled with gravel (3), or concrete grid pavers (CGP) filled with grass (4). The results of this study showed that the long-term behaviour of the infiltration capacity relies largely on the type and age of the system and the type of joint filling (gravel and grass). Furthermore, the study showed that the 11 year old concrete grid pavers filled with grass had the highest infiltration capacity (4.80 + 2.46 mm/min), whilst the 9 and 14 year old swales had the lowest infiltration capacity (0.10 + 0.00 mm/min).

  • 20.
    Al-Rubaei, Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Engström, Malin
    Växjö Municipality.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Blecken, Godecke-Tobias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Long-term treatment efficiency of a constructed stormwater wetland: preliminary results2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Constructed stormwater wetlands (CSWs) are commonly used in Sweden and worldwide because of their high efficiency in urban stormwater management. However, questions have been raised about the long-term performance of CSWs. This study investigated the performance of a 19-year-old constructed wetland, which was designed to treat the stormwater from a 320-ha catchment located in the city of Växjö, southern Sweden. The system has not been maintained since its construction in 1994. The results of the present study were compared with results obtained from a previous study conducted by Växjö Municipality in 1997. The results showed that the CSW significantly reduced peak flows by 72%. High concentration reductions were found for Cd, Cr, Cu, Zn, Pb, TSS and TP (90, 89, 91, 90, 96, 96 and 86%, respectively). TN concentrations were reduced by 61%. The results indicated that lack of maintenance had no effect on the performance of wetland system during this long period of operation (19 years). In contrast, especially the removal of Cu and nitrogen was enhanced compared to 1997, which may be due to maturing of the system. The results show that CSWs are resilient systems, which (provided that design is sufficient) can work efficiently for at least two decades.

  • 21.
    Al-Rubaei, Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Merriman, Laura S.
    Biological & Agricultural Engineering, North Carolina State University.
    Hunt, William F.
    Biological & Agricultural Engineering, North Carolina State University.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Marsalek, Jiri
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Blecken, Godecke-Tobias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Survey of the operational status of 25 Swedish municipal stormwater management ponds2017Inngår i: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 143, nr 6, artikkel-id 05017001Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    During the past 50 years, wet stormwater ponds have been constructed to reduce negative environmental impacts of urban stormwater discharges on receiving aquatic environments. However, in many jurisdictions there is little information on the current operational status of such ponds and their functioning. This paucity of information prompted a field survey of 25 Swedish municipal stormwater ponds, aged between 3 and 26 years. The pond survey focused on estimating the pond hydraulic loading and efficiency, the state of littoral vegetation, characteristics of bottom sediment in the inlet and outlet zones (sizes and the chemistry), and the overall operational pond status, including the access for maintenance. The hydraulic efficiencies of ponds were estimated for pond footprint shapes and relative locations of the inlets and outlets using literature data. The estimated hydraulic efficiencies correlated well with the pond length-to-width ratios and the ratio of the pond surface area to the impervious area of the runoff contributing catchment (i.e., the hydraulic loading). Littoral vegetation was inspected visually and found to be overgrown at some facilities, which impeded the maintenance access. Benthic sediments in ponds contained silt and clay (&lt;63&#x2009;&#x2009;&#x3BC;m" role="presentation" style="box-sizing: border-box; display: inline; line-height: normal; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;"><63  μm<63  μm), sand and gravel fractions, and when compared with the literature data, such sediments appeared relatively coarse. Chemical characteristics of sediments reflected anthropogenic (traffic) activities, but without excessive contamination warranting special disposal requirements. Of the 25 ponds surveyed, four were fenced off and inaccessible to machinery. In fact, the design of these four ponds was such that it made inspection and maintenance very difficult, which may pose potential risks to ponds operation. Fifty-four percent of the investigated ponds were in need of minor maintenance, primarily because of sediment and litter accumulation in their inflow and outflow sections. The fact that the inspection survey revealed relatively few minor issues that could be corrected easily demonstrates the importance of relatively simple regular inspections serving to detect minor problems at an early stage before they would seriously impact pond functioning. The above survey methodology should be helpful for developing similar low-cost surveys in other jurisdictions.

  • 22.
    Al-Rubaei, Ahmed Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Engström, Malin
    Växjö Municipality.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Blecken, Godecke-Tobias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Effectiveness of a 19-Year Old Combined Pond-Wetland System in Removing Particulate and Dissolved Pollutants2017Inngår i: Wetlands (Wilmington, N.C.), ISSN 0277-5212, E-ISSN 1943-6246, Vol. 37, nr 3, s. 485-496Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study monitored the stormwater runoff quantity and quality treatment performance of a 6.8 ha 19-year old combined pond-wetland system, located in south Sweden, over one year. The mean volume reductions for 53 storm events for the pond and wetland were 40% and 28%, respectively, while the mean flow reductions were 60% and 76%, respectively. Pollutant concentrations in the influent to the wetland were highly variable. The pond-wetland system could efficiently remove an average of 91%, 80%, 94%, 91%, 83% and 92% of TSS, TP, particulate Cd, Cu, Pb, and Zn, respectively, whereas the removal of particulate and dissolved Ni was highly variable with an average of 67% ± 62% and −5% ± 41%, respectively. The removal of TN, NH4-N and NO3 + NO2-N was highly variable with an average of 45% ± 27%, 12% ± 96% and 45% ± 43%, respectively. These removal percentages are high in comparison to other studies and underline that relatively old systems can also provide efficient treatment. Although the pond accounted for a substantial reduction of pollutant concentration, the wetland significantly enhanced both the treatment performance and the peak flow reduction. This underlines that a combined pond/wetland system is a more beneficial solution than a pond only. The pollutant removal efficiency was significantly influenced by some factors including Antecedent Dry Days, seasonal variations, air temperature, retention times, rainfall depth and duration, and peak rainfall intensity.

  • 23.
    Al-Rubaei, Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Stenglein, Anna Lena
    Blecken, Godecke-Tobias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Can vacuum cleaning recover the infiltration capacity of a clogged porous asphalt?2012Inngår i: WSUD 2012: Water Sensitve Urban Design - 21 - 23 February 2012, Melbourne Cricket Ground : building the water sensitve community, Barton: Institution of Engineers, Australia , 2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Objective: The main threat for the performance of porous asphalt is clogging leading to decreased infiltration capacity. Thus, we investigated the potential of vacuum cleaning to recover the infiltration capacity of clogged permeable asphalts which have been in use for several decades. The influence of road operation and maintenance measures on the results was discussed.Method: We investigated the hydraulic conductivity (HC) of two roads with porous asphalt in Haparanda and Luleå, Sweden, which had been in use for 28 years and 15 years, respectively. A lack of appropriate maintenance during their operating life had lead to significant clogging and thus malfunction. The roads were vacuum cleaned using a vacuum cleaner/sweeping truck combination. This technology is recommended as a maintenance option for porous asphalt. Before and after the vacuum cleaning, replicate HC measurements were conducted using double-ring infiltrometers.Result: Before vacuum cleaning, mean HC was <0.1mm/min in Haparanda and between 0.4 and 0.8 mm/min in Luleå. After vacuum cleaning, HC increased significantly in Luleå (between 1.1 and 7.1mm/min) while no significant increase was detected in Haparanda. Despite the improvement after vacuum cleaning, HC was still far lower than the initial HC after construction. Reasons for the different results in Haparanda and Luleå were identified; the road winter maintenance was of primary importance.Conclusion: Depending on the extent of clogging, vacuum cleaning has the ability to recover HC of porous asphalt. However, long term behaviour of the HC depends largely on the street maintenance, thus regular appropriate maintenance is preferable.

  • 24.
    Al-Rubaei, Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Stenglein, Anna Lena
    Blecken, Godecke-Tobias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Long-term performance of a porous asphalt pavement in Luleå, Sweden: preliminary results2011Konferansepaper (Annet vitenskapelig)
  • 25.
    Al-Rubaei, Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Stenglein, Anna Lena
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Blecken, Godecke-Tobias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Long-term hydraulic performance of porous asphalt pavements in northern Sweden2013Inngår i: Journal of irrigation and drainage engineering, ISSN 0733-9437, E-ISSN 1943-4774, Vol. 139, nr 6, s. 499-505Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effect of clogging on the long-term infiltration capacity and porosity of two 18- and 24-year-old porous asphalts was examined by using replicate double-ring infiltrometer tests and analyzing asphalt core samples. Tests were carried out to see if high pressure washing and vacuum cleaning could restore the hydraulic performance. The infiltration capacity of the porous asphalts decreased substantially, primarily due to surficial clogging (0.50 +/- 0.26 in Lulea, Sweden, and 0.22 +/- 0.12 in Haparanda, Sweden, compared to initially > 290 mm min(-1)). In Lulea, washing and vacuum cleaning could partially restore the infiltration capacity (3.48 +/- 3.00 mm min(-1)), but in Haparanda, no effect was measured. The porosity was constantly between 16 and 18%. The difference of the long-term behavior and effect of cleaning in Lulea and Haparanda is primarily attributable to different street maintenance, age, and winter maintenance (application of fine gravel and/or sand). Although the infiltration capacity in Lulea was far below initial values, the asphalt still has the capacity to infiltrate an intense design rainfall (100 year average return interval, 15 min duration), underlining that porous asphalt can be a resilient feature also under nonfavorable conditions

  • 26.
    Al-Rubaei, Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Blecken, Godecke-Tobias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Long-term hydraulic performance of stormwater infiltration systems2015Inngår i: Urban Water Journal, ISSN 1573-062X, Vol. 12, nr 8, s. 660-671Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Despite the common use of stormwater infiltration systems, there is still only limited data available evaluating the long-term hydraulic function of such systems. The hydraulic performance of twelve stormwater infiltration systems (vegetated and unvegetated concrete grid pavers, unvegetated interlocking concrete pavers and grassed swales) was therefore investigated in field and laboratory environments in Växjö, Sweden. The systems investigated had not been subjected to regular maintenance to sustain infiltration capacity. Due to this, and the fact that, for most systems, an inappropriate joint filling material was used and (at the swales) there was severe compaction, most systems showed a reduced infiltration capacity. Despite this, especially the older vegetated systems, were still capable of infiltrating intense design rainfalls. This study showed the influence of some factors (type and age of the system, the type of joint filling material (grass and macadam) and the distance from the edge of the pavement) on the long-term behaviour of the infiltration capacity. In conclusion, there is a significant risk that existing stormwater infiltration systems are not working adequately in praxis. Proper implementation of construction and regular control by the inspecting authority has to be ensured.

  • 27.
    Altorkmany, Lobna
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Kharseh, Mohamad
    Civil Environmental Engineering Department, Chalmers University of Technology.
    Ljung, Anna-Lena
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Lundström, Staffan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Experimental and Simulation Validation of ABHE for Disinfection of Legionella in Hot Water Systems2017Inngår i: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 116, s. 253-265Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The work refers to an innovative system inspired by nature that mimics the thermoregulation system that exists in animals. This method, which is called Anti Bacteria Heat Exchanger (ABHE), is proposed to achieve continuous thermal disinfection of bacteria in hot water systems with high energy efficiency. In particular, this study aims to demonstrate the opportunity to gain energy by means of recovering heat over a plate heat exchanger. Firstly, the thermodynamics of the ABHE is clarified to define the ABHE specification. Secondly, a first prototype of an ABHE is built with a specific configuration based on simplicity regarding design and construction. Thirdly, an experimental test is carried out. Finally, a computer model is built to simulate the ABHE system and the experimental data is used to validate the model. The experimental results indicate that the performance of the ABHE system is strongly dependent on the flow rate, while the supplied temperature has less effect. Experimental and simulation data show a large potential for saving energy of this thermal disinfection method by recovering heat. To exemplify, when supplying water at a flow rate of 5 kg/min and at a temperature of 50 °C, the heat recovery is about 1.5 kW while the required pumping power is 1 W. This means that the pressure drop is very small compared to the energy recovered and consequently high saving in total cost is promising.

  • 28. Altorkmany, Lobna
    et al.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Overview of legionella bacteria infection: control and treatment methods2009Konferansepaper (Annet vitenskapelig)
  • 29.
    Altorkmany, Lobna
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Overview of Legionella Bacteria Infection: Control and Treatment Methods2009Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Since the first recognized outbreak of Legionnaires' disease (LD) in 1976, it has become an increasing problem around the world especially in poor countries. Legionella (L) causes an estimated 15,000 annual cases of pneumonia in USA, and leads to death in about 20% of the cases. L is found worldwide in both natural and artificial environments e.g. spa pools, cooling towers. It infects people by inhaled contaminated aerosols that can transmit several km. The optimal temperature for L growth is 20-45C. Control of L is therefore an important health issue. Many treatment methods are used; biocides, ionisation, ozone, UV-radiation, pressure, and thermal treatment. Only thermal treatment can completely eliminate L, which is killed almost instantly at 70C. Current paper gives an overview of the Legionella problem and treatment methods.

  • 30.
    Amara, S.
    et al.
    Unité de Recherche en Energies Renouvelables en Milieu Saharien (URER/MS).
    Benyoucef, B.
    Unité de Recherche Matériaux et Energies Renouvelables (URMER), Université de Tlemcen.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Touzi, A.
    Unité de Recherche en Energies Renouvelables en Milieu Saharien (URER/MS).
    Benmoussat, A.
    Unité de Recherche Matériaux et Energies Renouvelables (URMER), Université de Tlemcen.
    Experimental study of a concentration heating system with optical fiber supply2009Inngår i: Abstract book and proceedings : Effstock 2009: 11th International conference on Thermal Energy Storage for Energy Efficiency and Sustainability / [ed] Signhild Gehlin, Stockholm: Energi- och Miljötekniska Föreningen / EMTF Förlag , 2009Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The buildings thermal function is important to provide comfort to its tenants. This means to provide cooling during hot seasons and/or heating in cold season. Current study concerns modelling of a new design of thermal photo sensors that results in a more efficient heating for Tlemcen site, Algeria.

  • 31.
    Amara, S.
    et al.
    Unité de Recherche en Energies Renouvelables en Milieu Saharien (URER/MS).
    Benyoucef, B.
    Unité de Recherche Matériaux et Energies Renouvelables (URMER), Université de Tlemcen.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Touzi, A.
    Unité de Recherche Matériaux et Energies Renouvelables (URMER).
    Benmoussat, A.
    Unité de Recherche Matériaux et Energies Renouvelables (URMER), Université de Tlemcen.
    Experimental study of a domestic hot water storage tank thermal behaviour2009Inngår i: Abstract book and proceedings : Effstock 2009: 11th International conference on Thermal Energy Storage for Energy Efficiency and Sustainability / [ed] Signhild Gehlin, Stockholm: Energi- och Miljötekniska Föreningen / EMTF Förlag , 2009Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Much work has been carried out on hot water storage during the last 20-30 years, particularly on solar heat applications. Theoretical and experimental studies on the internal heat transfer have been made at laboratory scale and at larger scales. Current study, which was conducted in order to understand the stratification phenomena, involved an experimental study on the thermal behaviour in a hot water tank during charging and discharging for domestic hot water storage. Results showed no effect of stratification due to the injection fluid from the bottom of the tank and the effect of mixed convection induced by the temperature difference which created a mixture inside the tank, where the temperature was uniform across the height, and the apparition of stratification due to the fact of discharge from the bottom of the tank.

  • 32.
    Amara, Saidi
    et al.
    Unité de Recherche Matériaux et Energies Renouvelables (URMER), Université de Tlemcen.
    Baghdadli, T.
    Unité de Recherche Matériaux et Energies Renouvelables (URMER), Université de Tlemcen.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Khimulu, R.
    Unité de Recherche Matériaux et Energies Renouvelables (URMER), Université de Tlemcen.
    Solar System Design for Water Treatment: Antibacterial Heat Exchanger (ABHE)2017Inngår i: Innovative Healthcare Systems for the 21st Century / [ed] Hassan Qudrat-Ullah, Peter Tsasis, Springer International Publishing , 2017, s. 167-180Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Current study concerns the fundamental problems to eliminate pathogens that are responsible for waterborne diseases. These illnesses, which have followed man throughout history, are described by occurring symptoms such as diarrhea and nausea. The various organisms identified within this document as waterborne bacterial pathogens are, e.g., Legionella (causes Pontiac fever), Salmonella (typhoid fever), and Yersinia (plague). Several control methods are available for water disinfection: biocide, ultraviolet light sterilization, copper–silver ionization, ozonation, etc., but only thermal treatment can eliminate bacterial pathogens, which are killed almost instantly at 70 °C. The current chapter describes water disinfection by a solar concentrator combined with a heat recovery system that reduces the heat demand. Though this study is made for a small system (160 l of hot water per day), the system can be enlarged (more hot water and more solar collector area), and the results are thus valid also for such larger systems. Here experiments of water treatment by a solar concentrator are summarized and analyzed where the temperature exceeds 80 °C at the outlet of the heat exchanger.

  • 33.
    Amara, Sofiane
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Corrigendum to “Using Fouggara for Heating and Cooling Buildings in Sahara” (Energy Procedia 6 (2011), 55–64)2011Inngår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 6, s. 825-Artikkel i tidsskrift (Fagfellevurdert)
  • 34.
    Amara, Sofiane
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Novel and ancient technologies for heating and cooling buildings2011Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The basic issue of this thesis concerns one of the fundamental problems of the future of our society: How to meet the energy requirements for a large and growing world population while preserving our environment? This question is important for the world and the answers are complex and interwoven.Conventional energy sources, fossil and fissile, are polluting in the present and in the future: they erode the environment and their resources are limited. Renewable energy (hydro, wind, solar, geothermal) constitutes a minimum of pollution in the different energy systems. The technologies for using renewable energy are well known though further development and progress are made. This development also requires behavioural change, adaptation, and above all political will. The transition from an economy based on fossil energy to an economy based on renewable energy appears necessary for the protection of the environment. The cost of renewable energy is often represented as an obstacle but remains competitive in the long run.The development and availability of renewable energy, which varies because of its spatial and temporal distribution, require an adaptation of lifestyle, habits, habitat design (passive bioclimatic houses), urban planning and transportation.The focus of this thesis was to apply renewable energy in an area with hot summers and cold winter, a climate like that in the northwest of Algeria. In order to provide improved comfort in the buildings and also economic development in this area, the energy demand for heating and cooling was analyzed in the ancient city of Tlemcen. To supply domestic hot water and space heating, water must be simultaneously available at two different temperature levels. Cold water temperature, close to that of the atmosphere, and hot water between 50 and 60°C. An interesting feature of the preparation of hot water is the small variation of requirements during the year, unlike that to heating. The preparation of hot water is one of the preferred applications of solar energy in the building for several reasons. For this reason an experimental study of the thermal behaviour of a domestic hot water storage tank was undertaken. The phenomena that affect the thermal behaviour of tank especially the coupling between the solar collector and storage tank was studied. This study included concentrating solar collector in which optical fibers were used to transport the energy to the storage tank. Another technology was introduced and developed for the heating and cooling of buildings in the desert involving an existing ancient irrigation system called Fouggara. The novel idea is to use the Fouggara as an air conditioner by pumping ambient air through this underground system. Then air at a temperature of about 21°C would be supplied to the building for heating in the winter and cooling in the summer. This study shows the feasibility of using this ancient irrigation system of Fouggara and contributes to reducing and eliminating the energy demand for heating and cooling buildings in the Sahara desert.

  • 35.
    Amara, Sofiane
    et al.
    Université de Tlemcen, BP 119 Tlemcen.
    Baghdadli, Tewfik
    Université de Tlemcen, BP 119 Tlemcen.
    Knapp, Samuel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Legionella Disinfection by Solar Concentrator System2017Inngår i: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 70, s. 786-792Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The current study concerns the fundamental problems of Legionnaires disease. Four decades after Legionnaires' bacteria was first identified there is still a low level of clinical awareness. Humans are infected by inhalation of aerosolized water and/or soil contaminated with the bacteria. Several control methods are available for water disinfection: biocide, ultraviolet light sterilization, copper-silver ionization, ozonation etc. but only thermal treatment can completely eliminate Legionella, which is killed almost instantly at 70 °C. The current paper describes Legionella disinfection by a solar concentrator combined with a heat recovery system that reduces the heat demand. Though this study is made for a small system (160 l of hot water per day) the system can be enlarged (more hot water and more solar collector area) and the results are thus valid also for such larger systems. Here experiments of water treatment by a solar concentrator are summarized and analyzed where the temperature exceeds 80 °C at the outlet of the heat exchanger.

  • 36.
    Amara, Sofiane
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Benmoussat, A.
    Renewable Energy Research Unity in Saharien Middle, ‘URER/MS’.
    Benyoucef, B.
    Renewable Energy & Materials Research Unity, ‘URMER’.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Requirements energy estimate of heating & cooling for a dwelling in the site of Tlemcen2007Artikkel i tidsskrift (Fagfellevurdert)
  • 37.
    Amara, Sofiane
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Benyoucef, B.
    Université de Tlemcen, BP 119 Tlemcen.
    Using fouggara for heating and cooling buildings in Sahara2011Inngår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 6, s. 55-64Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In order to utilise naturally stored heat or cold from the ground, seasonal temperature variations are required. The reason is that the ground temperature is then warmer than the air temperature during winter and colder during summer. The heating and cooling demand in North Africa varies considerably with the greatest cooling demand in the East and the greatest heating demand in the West. In parts of Algeria the mean temperature difference between the coldest and warmest month is greater than 20 °C, which is favourable. In current work it was shown that the ancient Fouggara system, even today would be interesting for heating and cooling of buildings in the Sahara desert.

  • 38.
    Amara, Sofiane
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Benyoucef, B.
    Université de Tlemcen, BP 119 Tlemcen.
    Benmoussat, A.
    Université de Tlemcen, BP 119 Tlemcen.
    Concentration heating system with optical fiber supply2011Inngår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 6, s. 805-814Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper reports on an experimental realization and field testing of a recently proposed solar fiber optic mini dish light concentrator connected to a hot water accumulator. The prototype dish is 150 cm in diameter. In repeated test the collected and concentrated sunlight was transported in a one millimeter diameter optical fiber to a selective surface in the storage tank. This surface absorbs the radiation which remains trapped inside as it heat exchanges with tank fluid which temperature can reach 70 °C.

  • 39.
    Amofah, Lea Rastas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    A small scale wastewater treatment system adapted to nutrient recovery in cold climate: performance and possible sorbents2007Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Waterbodies are impaired by, among other things, discharge from onsite small- scale wastewater (WW) treatment systems. Hence, these systems need to be updated to improve the effluent quality and the reuse of nutrients within society. The objectives of this thesis were to find suitable sorbents for a small scale WW treatment system, to investigate the performance of a willow bed in cold climate and to evaluate the function of a proposed WW treatment system adapted to sustainable development in cold climate.Column experiments were performed to study the ammonium adsorption and desorption of clinoptilolite. Laboratory scale studies were conducted to estimate the phosphorus (P) retention of blast furnace slag (BF slag). Further, a full-scale WW treatment system was implemented in northern Sweden to evaluate the function of the system and its units over 16 months. The system comprised of a willow bed and two parallel P filters, namely BF slag and Filtralite-P. A stream of primarily treated WW from a village was pumped to the treatment system.The results from the column experiments showed that ammonium adsorption of the studied clinoptilolite and the desorption of previously adsorbed ammonium was too low to be an economically reasonable alternative for WW ammonium retention in small-scale WW treatment systems.The investigated weathered and coarse-grained BF slag had a low WW P retention, with the overall P sorption below 100 mg P/kg. Therefore, the material is not suitable for P retention. Fresh and fine-grained BF slag demonstrated to be an effective P sorbent in laboratory experiments. However, the release of sulphuric compounds from the BF slag was extensive and may hinder its utilisation as P sorbent.Filtralite-P was found to be a promising P sorbent with a WW P sorption of about 370 mg P/kg at the end of the full-scale experimental period, and still with remaining capacity to retain P.The willow bed functioned as a treatment step due the reduction of nutrients, solids and BOD, and there was no significant difference in winter and summer performance. Climatic conditions seemed not to be a hindrance for willow beds in northern Sweden. However, the stemwood produced in the willow bed would replace only a small fraction of a household’s energy need for heating and warm water.In the full-scale study, the treatment system with BF slag filter attained neither of the protection levels given by Swedish Environmental Protection Agency (SEPA) during the experimental period. The Filtralite-P treatment line fulfilled the requirements of the low protection level by SEPA for the 1 year operating period and the requirements of the high protection level for 2 months. The need of maintanance in the studied treatment system was small and the operation was steady.

  • 40.
    Amofah, Lea Rastas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Towards sustainability of environmental protection: recovery of nutrients from wastewater filtration and the washing of arsenic contaminated soils2012Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Conventional methods for wastewater treatment and remediation of the sites withcontaminated soils focus on protection of human health, receiving waters and theenvironment. Towards this end, these methods concentrate on the reduction or removal of polluting substances, and therefore, are not well suited for creating resources through the recovery of nutrients, energy and decontaminated soils. Hence, a new, more sustainable approach is promoted in this thesis and, besides meeting the protection requirements, takes into consideration the resources that can be recovered from the treatment processes, keeping in mind the energy use during such a recovery. To achieve this goal, a better knowledge of wastewater and contaminated soil treatment approaches needs to be developed, from a resource recovery perspective.In this thesis project, laboratory, pilot-scale and full-scale investigations were conducted to study phosphorus (P) sorption in blast furnace slag (BF slag) filters. Further, ammonium adsorption by, and desorption from, clinoptilolite was studied in laboratory columns. A full-scale wastewater treatment system, comprising a willow bed followed by two parallel P–filters with BF slag and Filtralite® P media was examined for the wastewater treatment efficiency, nutrient accumulation in willow biomass, and biomass production. In a similar way, laboratory, pilot-scale and full-scale investigations were conducted to examine arsenic (As) removal from As contaminated soils using physical separation and chemical extraction. Finally, the decontamination of the extraction effluents (contaminated by As) was studied by adjusting pH and adding a coagulant, iron chloride.Pollutant mobilisation and immobilisation were affected by pH, the organic mattercontent, redox potential, time (process duration) and temperature. Results showed that pollutants in the studied media have complex characteristics in terms of charge of species and redox speciation, and therefore, no general conclusions addressing all the conditions studied could be given. The P sorption capacity of BF slag was reduced by outdoor storage and weathering, and the content of organic substances in sewage seemed to have a more negative impact on the sorption process when using weathered BF slag. Arsenic mobilisation from As contaminated soils was affected by pH, the content of organic substances, and redox potential and the nature of these effects depended on the polluting chemicals (i.e. wood preservatives) and the content of calcium in the soil. Extractions at elevated temperatures facilitated high As mobilisation from the contaminated soils for short contact times, assuming that the extraction solution features vital for As mobilisation were not altered, and the fastest As mobilisation was achieved by using an acid oxalate citrate solution rather than reductive or alkaline extraction solutions at room temperatures.In the full-scale treatment system, the willow bed efficiently reduced the content of total suspended solids and biodegradable organic matter in the influent wastewater and prevented the clogging of downstream phosphorus filters during the one year of operation. The Filtralite® P treatment train simultaneously removed over 90 and 70% of BOD and P, respectively, during the experimental period, and therefore, fulfilled the requirements for the low protection level over the period of one year, except for tot-P excesses during the snowmelt period. In the case of tot-N reduction (50%), the high protection level was achieved. On the other hand, the treatment system with BF slag did not fulfil requirements for either low or high protection level, because the coarse-grained BF slag was inefficient in retaining P and the concentrations of oxygen consuming compounds were elevated downstream of the filter.The studied methods for recovering resources through treatment of wastewater and contaminated soils demonstrated a potential for improving environmental sustainability of these processes. Even though the willow bed did not accumulate nutrients from the fed wastewater to a high degree, it facilitated nutrient recovery in other treatment steps located downstream. Fresh, fine-grained BF slag showed capacity to recover P from wastewater, which was comparable to that of other efficient P sorbents. The BF slag material released high amounts of sulphuric compounds during the initial loading phase which consequently increased the concentration of oxygen consuming compounds in the filter effluent. Thus, the use of BF slag for P retention is not recommended when the effluent is discharged to sensitive receiving waters. Natural clinoptilolite studied showed a high capacity for adsorbing ammonium from the pre-treated wastewater, at low operating temperatures. Hence, the clinoptilolite filter has a potential to enhance N retention during the plant dormancy or prior to the maturity of willow beds when N retention is needed. However, the recovery of ammonium was limited by the inefficient desorption process using tap water without recycling the eluate. Fertigated willows grew nearly as well as in the south of Sweden, but in the highly loaded horizontal flow willow bed, the potential to produce biofuel was limited. To recover nutrients, willow clones with lateral growth are preferable. 90% of nutrients accumulated in the above-ground parts of willows could be recovered from the experimental site operated over three growing seasons, particularly when using dense planting and annual harvesting prior to leaf fall.Soil treatment, comprising the exclusion of the fine soil fraction prior to the chemical extraction with strong extraction agents applied at an elevated temperature, was efficient in decontaminating soils, even for short contact times. However, this treatment procedure results in an incomplete soil recovery (i.e. the recovered mass of soil after decontamination is appreciably smaller than the soil mass prior to decontamination), consumes a high amount of energy and lowers the soil quality, which limits the potential end-use of the decontaminated soil. The alkaline extraction effluents could be decontaminated at a pH of 4-5 with the addition of a coagulant. Also, the treatment of alkaline extraction effluents was facilitated by the exclusion of the fine soil fraction from the chemical extraction step. The use of acid oxalate-citrate extraction solution was judged infeasible because the decontamination of such extraction solution is complicated due to the high pH buffering and complexing capacity of the solution.

  • 41.
    Amofah, Lea Rastas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Hanaeus, Jörgen
    Nutrient recovery in a smallscale wastewater treatment plant in cold climate2006Inngår i: Vatten, ISSN 0042-2886, Vol. 62, nr 4, s. 355-368Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    An onsite wastewater treatment plant at Brändön, north of Luleå, receiving primarily treated wastewater from a village, was operated and investigated during one year. The wastewater flow was 0.5 m3/d. The main treatment steps were a prefilter, mainly to distribute the flow, a vegetation filter consisting of two different clones of Salix and two phosphorus filters with Filtralite-P and blast furnace slag (BF slag) operated in parallel. The willow bed reduction of BOD7 was in average about 80% and of phosphorus (P) and nitrogen (N) 20-30%. The main mechanism was believed to be filtration in the bed. The reduction through plant uptake was minor. The Filtralite-P filter reduced BOD7, P and N with 67%, 72% and 20%, respectively. The BF slag filter reduced P and N with 53% and 3%, respectively. The release of sulphuric compounds from the BF slag filter increased the BOD7 content in the effluent. The Filtralite-P system achieved the requirements of the normal protection level given by the Swedish Environmental Protection Agency but not all of the requirements of the high protection level. The BF slag system did not fullfil the requirements of the two protection levels.

  • 42.
    Amofah, Lea Rastas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Mattsson, Jonathan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Hedström, Annelie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Willow bed fertigated with domestic wastewater to recover nutrients in subarctic climates2012Inngår i: Ecological Engineering: The Journal of Ecotechnology, ISSN 0925-8574, E-ISSN 1872-6992, Vol. 47, s. 174-181Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Conventional methods for wastewater treatment emphasise protecting human health, receiving waters and the environment. Consequently, they are generally designed to reduce pollutant levels and are not well-suited for creating resources. This paper describes a new, more sustainable and energy-efficient approach to wastewater treatment that satisfies health and environmental standards while also facilitating resource recovery. A full-scale compact willow bed was intensively fertigated with domestic wastewater in a cold climate to examine biomass production, the recovery of nutrients in willow biomass, and wastewater treatment. The performance of the willow bed was assessed for two years, covering three growing seasons. The studied frost-tolerant willow clones produced good biomass yields per unit area (6–7 ton dry matter/ha and year) under intensive fertigation with dense planting and continuous harvesting. The biomass yield of willow species exhibiting vertical growth seemed to be greater than that for lateral growth species in the dense stands studied. In contrast to biomass production, nutrient recovery was facilitated by intensive fertigation, continuous harvesting and less dense planting with a horizontally growing willow clone. The estimated nitrogen accumulation in above-ground biomass was 210 kg/ha and that of phosphorus was 30 kg/ha. 90% of the accumulated nutrients in the above-ground biomass were removed from the site during the experimental period. However, the quantity of nutrients accumulated in the willow biomass represented only a small fraction of the loaded or removed amount. The willow bed was shown to be an efficient prefilter for reducing the abundance of particulate and organic matter, leaving the bulk of the remaining nutrients in forms that could be recovered in subsequent treatment steps.

  • 43.
    Amofah, Lea Rastas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Maurice, Christian
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Bhattacharya, Prosun
    Kungliga tekniska högskolan, KTH.
    Chemical extraction of As from a polluted soil2008Inngår i: Arsenic in the environment - Arsenic from nature to humans: Book of Abstracts, 2008, s. 205-Konferansepaper (Annet vitenskapelig)
  • 44.
    Amofah, Lea Rastas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Maurice, Christian
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Bhattacharya, Prosun
    KTH-International Groundwater Arsenic Research Group, Department of Land and Water Resources Engineering, Royal Institute of Technology (KTH),.
    Extraction of arsenic from soils contaminated with wood preservation chemicals2010Inngår i: Soil & sediment contamination, ISSN 1532-0383, E-ISSN 1549-7887, Vol. 19, nr 2, s. 142-159Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Three soil samples contaminated by chromated zinc arsenate (CZA) or chromated copper arsenate (CCA) were investigated in a laboratory scale to study As mobilization and to identify a chemical agent that could be used in soil washing to extract arsenic. Besides high As extraction, the cost, occupational health issues and technical aspects were considered when selecting the chemical. Arsenic is strongly bound to CZA/CCA soils; only ∼50% of the tot-As was removed from water-washed soils. High Fe or Al mobilization is not necessarily indicative of high As removal from CZA/CCA soils. A high Cu/As-ratio and a large amount of soluble Ca in the soil hampered As extraction. The high ratio can be an indication of stable Cu-arsenates in soil. Calcium can react with the extraction agent or with As during extraction. Sodium hydroxide, dithionite with citrate (and oxalate) (dithionite solutions), and oxalate with citrate were the most efficient chemicals for removing As from the soils. The disadvantages of using these strong chemicals are: a high cost (oxalate with citrate); damage to equipment (dithionite solutions); an adverse impact on occupational health (dithionite solutions); or a deterioration in soil quality after extraction (NaOH and dithionite solutons). Phosphate, solutions based on NH2OH·HCl, or citrate were not efficient in mobilizing As from the soils.

  • 45.
    Andersson, Annika
    Luleå tekniska universitet.
    Kylvatten som värmekälla för begränsing av istryck mot dammluckor till kraftverk: en experimentell studie av fördelningssystem1990Rapport (Annet vitenskapelig)
  • 46.
    Andersson, Annika
    et al.
    Luleå tekniska universitet.
    Andersson, Lars-Olof
    Luleå tekniska universitet.
    A field study of frazil ice accumulation and adhesion on trash racks1992Rapport (Annet vitenskapelig)
    Abstract [en]

    A field experiment to study frazil ice blockage of water intake trash racks in hydropower plants is described. The experiment, conducted during the 1990/1991 winter using a submerged video camera, was designed to investigate ice accumulation on trash racks and compare this with laboratory tests. Differences between ice accumulation and adhesion on steel bars with and without a rubber coating were examined. The submerged video camera functioned well and was found to be an excellent tool to document and evaluate these ice phenomena. Frazil ice problems occured in air temperatures as high as -4°C. Frazil ice accumulation started on the upper section of the trash racks and progressed downwards. Ice was mainly deposited on the upstream face of the racks. The rubber coating material, with its poor adhesion to ice, appeared to mitigate frazil ice problems in the intakes in two ways. Ice was much more easily removed from trash rack elements coated with rubber and frazil did not stick to coated trash racks under small depress of supercoolings.

  • 47.
    Andersson, Annika
    et al.
    Luleå University of Technology.
    Svensson, Urban
    Luleå University of Technology.
    A numerical model of water droplet trajectories1989Inngår i: POAC '89: 10th International conference on port and ocean engineering under arctic conditions / [ed] Kenneth B.E. Axelsson; Lennart Å. Fransson, Luleå: Luleå tekniska universitet, 1989, Vol. 2, s. 671-680Konferansepaper (Annet vitenskapelig)
  • 48.
    Andersson, Lars-Olof
    Luleå tekniska universitet.
    Adhesion of ice to polymer materials1989Inngår i: Poac 89: 10th International Conference on Port and Ocean Engineering under Artic Conditions, Luleå, Sweden, 12-16 June 1989 / [ed] Lennart Å. Fransson; Kennet B. Axelsson, Luleå: Högskolan i Luleå , 1989, Vol. 2, s. 786-985Konferansepaper (Fagfellevurdert)
  • 49.
    Andersson, Lars-Olof
    Luleå tekniska universitet.
    Ice accretion and ice adhesion to polymer material1993Licentiatavhandling, med artikler (Annet vitenskapelig)
  • 50.
    Andersson, Lars-Olof
    et al.
    Luleå tekniska universitet.
    Golander, Car-Gustaf
    SKEGA AB.
    Persson, Sture
    SKEGA AB.
    Ice adhesion to rubber materials1994Inngår i: Journal of Adhesion Science and Technology, ISSN 0169-4243, E-ISSN 1568-5616, Vol. 8, nr 2, s. 117-132Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The aim of this study was to investigate the interfacial shear strength between ice and rubbers. Different rubber materials containing only a polymer and curing agent (peroxide) were tested with regard to surface wettability and interfacial shear strength. The effect of different grades and amounts of carbon black filler was also studied. The wettability was determined from contact angles, using water and diiodomethane as test liquids, measured on carefully cleaned and mirror smooth rubber sheets.

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