Change search
Refine search result
1 - 2 of 2
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Yang, James
    et al.
    Vattenfall AB, Research & Development (R & D), Hydraulic Laboratory, Älvkarleby, Sweden;Division of Resources, Energy & Infrastructure, Royal Institute of Technology, Stockholm, Sweden.
    Andreasson, Patrik
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics. Vattenfall AB, Research & Development (R & D), Hydraulic Laboratory, Älvkarleby, Sweden.
    Teng, Penghua
    Division of Resources, Energy & Infrastructure, Royal Institute of Technology, Stockholm, Sweden.
    Xie, Qiancheng
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    The Past and Present of Discharge Capacity Modeling for Spillways: A Swedish Perspective2019In: Fluids, E-ISSN 2311-5521, Vol. 4, no 10, article id 4010010Article in journal (Refereed)
    Abstract [en]

    Most of the hydropower dams in Sweden were built before 1980. The present dam-safety guidelines have resulted in higher design floods than their spillway discharge capacity and the need for structural upgrades. This has led to renewed laboratory model tests. For some dams, even computational fluid dynamics (CFD) simulations are performed. This provides the possibility to compare the spillway discharge data between the model tests performed a few decades apart. The paper presents the hydropower development, the needs for the ongoing dam rehabilitations and the history of physical hydraulic modeling in Sweden. More than 20 spillways, both surface and bottom types, are analyzed to evaluate their discharge modeling accuracy. The past and present model tests are compared with each other and with the CFD results if available. Discrepancies do exist in the discharges between the model tests made a few decades apart. The differences fall within the range −8.3%–+11.2%. The reasons for the discrepancies are sought from several aspects. The primary source of the errors is seemingly the model construction quality and flow measurement method. The machine milling technique and 3D printing reduce the source of construction errors and improve the model quality. Results of the CFD simulations differ, at the maximum, by 3.8% from the physical tests. They are conducted without knowledge of the physical model results in advance. Following the best practice guidelines, CFD should generate results of decent accuracy for discharge prediction.

    Download full text (pdf)
    fulltext
  • 2.
    Yang, James
    et al.
    Vattenfall, R&D Hydraulic Laboratory, Älvkarleby, Sweden; Civil and Architectural Engineering, Royal Institute of Technology, Stockholm, Sweden .
    Teng, Penghua
    Civil and Architectural Engineering, Royal Institute of Technology, Stockholm, Sweden .
    Xie, Qiancheng
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Li, Shicheng
    Civil and Architectural Engineering, Royal Institute of Technology, Stockholm, Sweden .
    Understanding Water Flows and Air Venting Features of Spillway: a Case Study2020In: Water, E-ISSN 2073-4441, Vol. 12, no 8, article id 2106Article in journal (Refereed)
    Abstract [en]

    For safe spillway discharge of floods, attention is paid to the water flow. The resulting air flow inside the facility, an issue of personnel security, is sometimes disregarded. The spillway in question comprises two surface gates and two bottom outlet gates lying right below. Air passages to the outlet gates include an original gallery and a recently constructed vertical shaft. To understand water-air flow behavior, 3D CFD modelling is performed in combination with the physical model tests. The simulations are made with fully opened radial gates and at the full pool water level (FPWL). The results show that the operation of only the bottom outlets leads to an air supply amounting to ~57 m3/s, with the air flow rates 35 and 22 m3/s to the left and right outlets. The air supply to the right outlet comes from both the shaft and the gallery. The averaged air velocity in the shaft and the gallery are approximately 5 and 7 m/s. If only the surface gates are fully open, the water jet impinges upon the canal bottom, which encloses the air space leading to the bottom outlets; the air flow rate fluctuates about zero. If all the four gates are open, the total air demand is limited to ~10 m3/s, which is mainly attributable to the shear action of the meeting jets downstream. The air demand differs significantly among the flow cases. It is not the simultaneous discharge of all openings that results in the largest air demand. The flood release from only the two outlets is the most critical situation for the operation of the facility. The findings should provide reference for spillways with the same or similar layout

    Download full text (pdf)
    fulltext
1 - 2 of 2
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf