EFFECT OF VALVE-CLOSURE SCHEDULE ON WATER HAMMER

The computerized method of characteristics was used to analyze, for a single pipeline discharging into free air, the effect of valve-closure schedule on water hammer under turbulent friction conditions. The inherent valve schedule was assumed to be a simple continuous power function of the fraction of the closing time, this function yielding a variety of standard valve configurations. A chart is presented to determine the valve schedule that should be used to yield minimum water hammer pressure. With the exception of the minimum pressure case, the same water hammer strength can be obtained with two different schedules. This follows from the type of schedule function used and from the compatibility equations of unsteady flow through closed conduits. Also, it was found that cavitation is less serious for an inherent valve schedule in which the bulk of the pressure surge occurs during the second part rather than during the first part of valve-closure.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/8672558
• Corporate Authors:

  American Society of Civil Engineers

  345 East 47th Street
  New York, NY  United States  10017-2398
• Authors:
  • Azoury, P H
  • Baasiri, M
  • Najm, H
• Publication Date: 1986-10

Media Info

• Features: Appendices; Figures; References;
• Pagination: p. 890-903
• Serial:
  • Journal of Hydraulic Engineering
  • Volume: 112
  • Issue Number: 10
  • Publisher: American Society of Civil Engineers
  • ISSN: 0733-9429
  • Serial URL: https://ascelibrary.org/journal/jhend8

Subject/Index Terms

• TRT Terms: Cavitation (Mechanics); Conduits; Equations; Impacts; Lane closure; Minimization; Unsteady flow; Valve timing; Water; Water pressure
• Uncontrolled Terms: Closures; Compatibility
• Old TRIS Terms: Closed conduits; Water effects
• Subject Areas: Highways; Hydraulics and Hydrology; I26: Water Run-off - Freeze-thaw;

Filing Info

• Accession Number: 00458470
• Record Type: Publication
• Report/Paper Numbers: ASCE Paper 20937
• Files: TRIS
• Created Date: Oct 31 1986 12:00AM