Steady-state hydraulic computer models are commonly used by water utilities for design
analyses and operations control related to water flow, pressure, and quality applications.
Typical analyses using computer models include sizing pipes, estimating available fire
flows, managing chlorine residuals, and minimizing water age. Transient hydraulic
models, though used less frequently, can be used to: evaluate the potential effects of transient pressures on water
system equipment and water quality; properly design surge control equipment; and, to
establish system operation procedures that minimize the occurrence and magnitude of
transient pressures. Analysis of pressure transients,
often referred to as surge or water hammer analysis, is more complex than traditional
steady-state hydraulic analysis and is consequently often neglected in favor of basic hand
calculated estimations, traditional rules of thumb, and engineering judgment. However,
development of new and improved transient analysis software and improved computer
processor speeds have reduced the primary obstacles, namely the expense and difficulty
of analyses, which often preclude the use of transient analyses in the design and operation
of water system facilities.
The use of transient hydraulic models in the design and operation of water systems and
water system facilities is the focus of this paper, with an emphasis on the need for
computer model analyses. Typical transient hydraulic analyses examples are provided to
demonstrate the usefulness of this technology. Case studies are used to demonstrate why
rules of thumb and basic hand calculations often cannot provide the basis for adequate
transient control and optimized operating procedures. The case studies also provide
examples of transient pressures that could be developed by inadequate or over-designed
surge control equipment, which are often specified when transient computer model
analyses are not performed, and can significantly worsen the original transient pressure
problems.
Includes 2 references, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 250 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 14 |
| Published : | 04/18/2004 |
