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Gustavsson, Håkan
Publications (10 of 42) Show all publications
Khayamyan, S., Lundström, T. S. & Gustavsson, H. (2014). Experimental investigation of transitional flow in porous media with usage of a pore doublet model (ed.). Paper presented at . Transport in Porous Media, 101(2), 333-348
Open this publication in new window or tab >>Experimental investigation of transitional flow in porous media with usage of a pore doublet model
2014 (English)In: Transport in Porous Media, ISSN 0169-3913, E-ISSN 1573-1634, Vol. 101, no 2, p. 333-348Article in journal (Refereed) Published
Abstract [en]

The transition from laminar to turbulent flow in porous media is studied with a new method. To mimic inter-connected pores, a simplified geometry is studied consisting of a pipe with a relatively large diameter that is split into two parallel pipes with different diameters. This is a pore-doublet set-up and the pressure drops over the parallel pipes are recorded by pressure transducers for different flow rates. Results show that the flow in the parallel pipes is redistributed when turbulent slugs pass through one of them. The presence of the slugs is revealed by positive skewness in the pressure signals as well as an increase of the standard deviation of the pressure drops and correlation between the pressure drops of the pipes. A frequency analysis of the pressure drops show that lower band frequency pressure variations in one pipe are communicated to the other pipe while higher band frequencies are filtered out.

National Category
Fluid Mechanics and Acoustics
Research subject
Fluid Mechanics
Identifiers
urn:nbn:se:ltu:diva-13049 (URN)10.1007/s11242-013-0247-6 (DOI)000328856600010 ()2-s2.0-84890887214 (Scopus ID)c35008f2-1bbe-4a95-9224-ebfa72845656 (Local ID)c35008f2-1bbe-4a95-9224-ebfa72845656 (Archive number)c35008f2-1bbe-4a95-9224-ebfa72845656 (OAI)
Note
Validerad; 2014; 20131101 (stlu)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Green, T., Lindmark, E., Lundström, S. & Gustavsson, H. (2011). Flow characterization of an attraction channel as entrance to fishways (ed.). Paper presented at . Rivers Research and Applications: an international journal devoted to river research and management, 27(10), 1290-1297
Open this publication in new window or tab >>Flow characterization of an attraction channel as entrance to fishways
2011 (English)In: Rivers Research and Applications: an international journal devoted to river research and management, ISSN 1535-1459, E-ISSN 1535-1467, Vol. 27, no 10, p. 1290-1297Article in journal (Refereed) Published
Abstract [en]

The flow field inside and downstream of an open channel placed near the surface of a free flow (such as the tail water of a turbine) is characterized in detail. The channel cross-section is U-shaped and in the downstream end is placed a ramp on the bottom which accelerates the flow passing through the channel. This flow is intended to catch the attention of fish and improve their entrance to fishways, which has also been successfully demonstrated in field tests.

Abstract [en]

The flow field inside and downstream of an open channel placed near the surface of a free flow (such as the tail water of a turbine) is characterized in detail. The channel cross-section is U-shaped and in the downstream end is placed a ramp on the bottom which accelerates the flow passing through the channel. This flow is intended to catch the attention of fish and improve their entrance to fishways, which has also been successfully demonstrated in field tests.The flow through the channel is subcritical and the ramp thus blocks some water from passing through. To find the optimum vertical position of the channel, a down-scaled model channel is placed in a water flume and flow fields in vertical planes directed along the flow are visualized using particle image velocimetry. Results show that increasing the depth over the ramp has little effect on the maximum velocity while it makes the accelerated water more perceptible downstream the channel. This will most likely improve the channel's ability to attract fish. It is also shown that a recirculation zone is formed in the channel for the small depths tested. Finally, it is shown that a modest tilt of the channel will not affect the flow field in any significant way.

National Category
Fluid Mechanics and Acoustics
Research subject
Fluid Mechanics
Identifiers
urn:nbn:se:ltu:diva-9776 (URN)10.1002/rra.1426 (DOI)000298234800010 ()2-s2.0-81855166746 (Scopus ID)8755b7b0-71c5-11dc-86ab-000ea68e967b (Local ID)8755b7b0-71c5-11dc-86ab-000ea68e967b (Archive number)8755b7b0-71c5-11dc-86ab-000ea68e967b (OAI)
Note
Validerad; 2011; 20071003 (ysko)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Khayamyan, S., Gustavsson, H. & Lundström, T. S. (2011). Transition from laminar to turbulent flow in porous media (ed.). Paper presented at Svenska mekanikdagar 2011 : 13/06/2011 - 15/09/2011. Paper presented at Svenska mekanikdagar 2011 : 13/06/2011 - 15/09/2011.
Open this publication in new window or tab >>Transition from laminar to turbulent flow in porous media
2011 (English)Conference paper, Oral presentation only (Refereed)
National Category
Fluid Mechanics and Acoustics
Research subject
Fluid Mechanics
Identifiers
urn:nbn:se:ltu:diva-39555 (URN)e5e058c4-1b8c-4cf3-9b42-5886ff5171a9 (Local ID)e5e058c4-1b8c-4cf3-9b42-5886ff5171a9 (Archive number)e5e058c4-1b8c-4cf3-9b42-5886ff5171a9 (OAI)
Conference
Svenska mekanikdagar 2011 : 13/06/2011 - 15/09/2011
Note
Godkänd; 2011; 20111010 (ysko)Available from: 2016-10-03 Created: 2016-10-03 Last updated: 2017-11-25Bibliographically approved
Gustavsson, H. (2009). Non-linear wave interactions from transient growth in plane-parallel shear flows (ed.). Paper presented at . European journal of mechanics. B, Fluids, 28(3), 420-429
Open this publication in new window or tab >>Non-linear wave interactions from transient growth in plane-parallel shear flows
2009 (English)In: European journal of mechanics. B, Fluids, ISSN 0997-7546, E-ISSN 1873-7390, Vol. 28, no 3, p. 420-429Article in journal (Refereed) Published
Abstract [en]

Based on the normal velocity-normal vorticity (v - η) formulation for the development of 3D disturbances in plane-parallel shear flows, the non-linear terms in the governing equations are derived as convolution integrals of the Fourier-transformed variables. They are grouped in three categories: v - v, v - η and η - η terms, and are expressed in a simple geometric form using the modulus of the two wave-vectors (k′ and k″) appearing in the convolution integrals, and their intervening angle (χ). The non-linear terms in the v-equation involving η are all weighted by sin χ (or sin2 χ). This confirms the known result that non-linear regeneration of normal velocity, necessary for a sustained driving of 3D disturbances, is not possible for stream-wise elongated structures (α = 0), only. It is therefore suggested how transiently amplified η can interact with decaying 2D waves to activate (oblique) waves which may be less damped than the 2D wave. This is shown to be possible for Blasius flow. In the η-equation, non-linear effects are possible for elongated structures resulting in shorter spanwise scales appearing at a shorter time-scale than the (linear) transient growth. A numerical example shows the details of this process in plane Poiseuille flow. From an inspection of the y-dependency (wall-normal direction) of the non-linear terms it is suggested that higher y-derivatives may give rise to non-linear effects in the inviscid development of perturbations. Also, a result for the y-symmetry of the non-linear terms is derived, applicable to plane Poiseuille flow.

Keywords
Engineering mechanics - Fluid mechanics, Teknisk mekanik - Strömningsmekanik
National Category
Fluid Mechanics and Acoustics
Research subject
Fluid Mechanics
Identifiers
urn:nbn:se:ltu:diva-9201 (URN)10.1016/j.euromechflu.2008.10.001 (DOI)000265341500007 ()2-s2.0-62349087017 (Scopus ID)7c3a19b0-29b7-11de-adf6-000ea68e967b (Local ID)7c3a19b0-29b7-11de-adf6-000ea68e967b (Archive number)7c3a19b0-29b7-11de-adf6-000ea68e967b (OAI)
Note
Validerad; 2009; 20090415 (ysko)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Gustavsson, H., Weihed, P., Nordlund, E., Forsling, W., Öhlander, B. & Forssberg, E. (2009). Norrländsk vattenkraft och gruvnäring: två svenska välståndsbyggare. In: Roger Jacobsson (Ed.), Thule: Kungl. Skytteanska samfundets årsbok 2009 (pp. 331-345). Paper presented at . Umeå: Kungl. Skytteanska samfundet
Open this publication in new window or tab >>Norrländsk vattenkraft och gruvnäring: två svenska välståndsbyggare
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2009 (Swedish)In: Thule: Kungl. Skytteanska samfundets årsbok 2009, Umeå: Kungl. Skytteanska samfundet , 2009, p. 331-345Chapter in book (Other (popular science, discussion, etc.))
Place, publisher, year, edition, pages
Umeå: Kungl. Skytteanska samfundet, 2009
National Category
History of Technology Fluid Mechanics and Acoustics Geology Other Civil Engineering Geochemistry
Research subject
History of Technology; Fluid Mechanics; Ore Geology; Mining and Rock Engineering; Applied Geology
Identifiers
urn:nbn:se:ltu:diva-20035 (URN)15b834b0-d5c9-11de-bae5-000ea68e967b (Local ID)978-91-86438-36-4 (ISBN)15b834b0-d5c9-11de-bae5-000ea68e967b (Archive number)15b834b0-d5c9-11de-bae5-000ea68e967b (OAI)
Note

Godkänd; 2009; 20091120 (ysko)

Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-03-15Bibliographically approved
Davidsson, N. & Gustavsson, H. (2008). Elementary solutions for streaky structures in boundary layers with and without suction (ed.). Paper presented at . Fluid Dynamics Research, 40(3), 212-231
Open this publication in new window or tab >>Elementary solutions for streaky structures in boundary layers with and without suction
2008 (English)In: Fluid Dynamics Research, ISSN 0169-5983, E-ISSN 1873-7005, Vol. 40, no 3, p. 212-231Article in journal (Refereed) Published
Abstract [en]

The temporal evolutions of small, streamwise elongated disturbances in the asymptotic suction boundary layer (ASBL) and the Blasius boundary layer (BBL) are compared. In particular, initial perturbations localized (δ-functions) in the wall-normal direction are studied, corresponding to an axi-symmetric jet coming out of a plane parallel to the flat plate. Analytical solutions are presented for the wall-normal and streamwise velocities in the ASBL case whereas both analytical and numerical methods are used for the BBL case. The initial position of the perturbation and its spanwise wave number are varied in a parameter study. We present results of maximum amplitudes obtained, the time to reach them, their position and optimal spanwise scales. Free-stream disturbances are shown to migrate towards the wall and reach their (negative) optimum inside the boundary layer. The migration is faster for the ASBL case and a larger amplitude is reached than for the BBL. For perturbations originating inside the boundary layer the amplitudes are overall larger and show the phenomenon of overshoot, i.e. positive amplitudes moving out of the boundary layer. The overall largest amplitudes are obtained for the BBL case, as in other studies, but it is shown that for free-stream disturbances initiated somewhere downstream the leading edge streak growth may be amplified due to suction since in the BBL the disturbance mainly advects above the boundary layer.

National Category
Fluid Mechanics and Acoustics
Research subject
Fluid Mechanics
Identifiers
urn:nbn:se:ltu:diva-4258 (URN)10.1016/j.fluiddyn.2007.08.002 (DOI)2-s2.0-38649084457 (Scopus ID)22f07c10-7395-11dd-a60f-000ea68e967b (Local ID)22f07c10-7395-11dd-a60f-000ea68e967b (Archive number)22f07c10-7395-11dd-a60f-000ea68e967b (OAI)
Note
Validerad; 2008; 20080826 (ysko)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Lindmark, E. & Gustavsson, H. (2008). Field study of an attraction channel as entrance to fishways (ed.). Paper presented at . Rivers Research and Applications: an international journal devoted to river research and management, 24(5), 564-570
Open this publication in new window or tab >>Field study of an attraction channel as entrance to fishways
2008 (English)In: Rivers Research and Applications: an international journal devoted to river research and management, ISSN 1535-1459, E-ISSN 1535-1467, Vol. 24, no 5, p. 564-570Article in journal (Refereed) Published
Abstract [en]

A flow device that accelerates turbine tail water (or any free stream) to act as an attraction for migrating fish is field tested. The device consists of an open (U-shaped) channel which accelerates the incoming flow by a local constriction of the cross-sectional area. The velocity increase has previously been investigated in a lab-scale model and an increase of 38% has been established. In the summers of 2004 and 2005, a full-scale prototype of the attraction channel was tested at the Sikfors hydropower plant in the Pite River in Sweden. The channel was equipped with underwater cameras to monitor and record the fish swimming through it. The tests show that the fish do swim through the attraction channel. During the same time period in 2004 and 2005, 57 and 471 fishes swam through the channel, respectively. The major change of the channel between the two years was that it was painted black for 2005.

National Category
Fluid Mechanics and Acoustics
Research subject
Fluid Mechanics
Identifiers
urn:nbn:se:ltu:diva-11809 (URN)10.1002/rra.1145 (DOI)000257167800008 ()2-s2.0-47249134659 (Scopus ID)ad1f0b80-2d41-11dd-9c9b-000ea68e967b (Local ID)ad1f0b80-2d41-11dd-9c9b-000ea68e967b (Archive number)ad1f0b80-2d41-11dd-9c9b-000ea68e967b (OAI)
Note
Validerad; 2008; 20080529 (eliwas)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Lindmark, E., Green, T., Gustavsson, H. & Lundström, S. (2008). Increasing the attraction water velocity at fishway entrances: model and field experiments (ed.). In: (Ed.), Sigurdur Brynjolfsson; Olafur Petur Palsson; Jong H. Kim (Ed.), Proceedings of the 19th International Symposium on Transport Phenomena (ISTP-19): Reykjavik, Iceland, August 17-21, 2008. Paper presented at International Symposium on Transport Phenomena : 17/08/2008 - 21/08/2008. : University of Iceland, Faculty of Industrial Engineering, Mechanical Engineering and Computer Science
Open this publication in new window or tab >>Increasing the attraction water velocity at fishway entrances: model and field experiments
2008 (English)In: Proceedings of the 19th International Symposium on Transport Phenomena (ISTP-19): Reykjavik, Iceland, August 17-21, 2008 / [ed] Sigurdur Brynjolfsson; Olafur Petur Palsson; Jong H. Kim, University of Iceland, Faculty of Industrial Engineering, Mechanical Engineering and Computer Science , 2008Conference paper, Published paper (Refereed)
Abstract [en]

When Atlantic salmon (Salmo salar) and sea trout (Salmo trutta) migrates upstream rivers they encounter obstructions such as hydropower plants. To increase the water velocity at the fish inlet of a fishway an attraction channel is used. The channel increases the velocity without using extra attraction water from the reservoir. Field experiments show that fish use the channel, and lab experiments show that the water velocity out of the channel is 38 % higher than the surrounding velocity and the increased velocity lasts for about 18 water depths down stream.

Place, publisher, year, edition, pages
University of Iceland, Faculty of Industrial Engineering, Mechanical Engineering and Computer Science, 2008
National Category
Fluid Mechanics and Acoustics
Research subject
Fluid Mechanics
Identifiers
urn:nbn:se:ltu:diva-29789 (URN)362c0da0-7280-11dd-a60f-000ea68e967b (Local ID)362c0da0-7280-11dd-a60f-000ea68e967b (Archive number)362c0da0-7280-11dd-a60f-000ea68e967b (OAI)
Conference
International Symposium on Transport Phenomena : 17/08/2008 - 21/08/2008
Note
Godkänd; 2008; Bibliografisk uppgift: CD-ROM; 20080825 (eliwas)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2017-11-25Bibliographically approved
Lundström, S., Gustavsson, H., Jekabsons, N. & Jakovics, A. (2008). Wetting dynamics in multiscale porous media: porous pore-doublet model, experiment and theory (ed.). Paper presented at . AIChE Journal, 54(2), 372-380
Open this publication in new window or tab >>Wetting dynamics in multiscale porous media: porous pore-doublet model, experiment and theory
2008 (English)In: AIChE Journal, ISSN 0001-1541, E-ISSN 1547-5905, Vol. 54, no 2, p. 372-380Article in journal (Refereed) Published
Abstract [en]

Fiber reinforced composite materials often consist of fibers gathered in bundles. Thus, during manufacturing, a liquid resin impregnates a multiscale porous medium. For wetting systems the capillary pressure jump becomes much higher in the smaller pores, i.e., within the bundles, and in addition to any applied pressure gradient there will be a local driving pressure gradient between the small- and large-scale areas. Such gradients will influence mechanisms, such as void formation and particle filtration. Hence, it is of interest to clarify the mechanisms for the wetting in general and the influence from the detailed geometry of the fiber network in particular. In this article, a porous pore-doublet model is studied in order to determine if an overflow of liquid can explain a leading flow in the smaller capillaries, and at which conditions it takes place. Experiments, as well as theoretical calculations on this generic geometry show that the leading front can be in the smaller capillary, as well as in the larger one. The outcome is dependent on the actual permeability of the porous material being a parameter that determines to what extent the larger capillary feeds the smaller one.

National Category
Fluid Mechanics and Acoustics
Research subject
Fluid Mechanics
Identifiers
urn:nbn:se:ltu:diva-6544 (URN)10.1002/aic.11387 (DOI)000252478900004 ()2-s2.0-38849188525 (Scopus ID)4c5811b0-f593-11dc-ba71-000ea68e967b (Local ID)4c5811b0-f593-11dc-ba71-000ea68e967b (Archive number)4c5811b0-f593-11dc-ba71-000ea68e967b (OAI)
Note
Validerad; 2008; 20080319 (pafi)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Wassvik, E., Green, T., Gustavsson, H. & Lundström, S. (2007). Flow measurements of an attraction channel as entrance to fishways (ed.). In: (Ed.), (Ed.), 6th International Symposium on Ecohydraulics, 2007-02-18 to 2007-02-23, Christchurch, New Zealand: . Paper presented at International Symposium on Ecohydraulics : 18/02/2007 - 23/02/2007. Wellington: National Institute of Water and Atmospheric Research
Open this publication in new window or tab >>Flow measurements of an attraction channel as entrance to fishways
2007 (English)In: 6th International Symposium on Ecohydraulics, 2007-02-18 to 2007-02-23, Christchurch, New Zealand, Wellington: National Institute of Water and Atmospheric Research , 2007Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
Wellington: National Institute of Water and Atmospheric Research, 2007
National Category
Fluid Mechanics and Acoustics
Research subject
Fluid Mechanics
Identifiers
urn:nbn:se:ltu:diva-34117 (URN)83a11410-7289-11dc-86ab-000ea68e967b (Local ID)83a11410-7289-11dc-86ab-000ea68e967b (Archive number)83a11410-7289-11dc-86ab-000ea68e967b (OAI)
Conference
International Symposium on Ecohydraulics : 18/02/2007 - 23/02/2007
Note
Godkänd; 2007; 20071004 (ysko)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2017-11-25Bibliographically approved
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