Abstract
Transient flow in a pipe was studied using both experimental and computer models. Numerical method such as the method of characteristics and an implicit method are presented and discussed herein. Experiments for transient flow in a pipe were conducted to verify the computer model including steady state head losses in a pipe. The steady state head loss coefficient based on the Darcy-Weisbach friction coefficient underestimates the energy reduction in the analysis of transient flow. To overcome the overestimation of pressure fluctuation and underestimation of long-term energy decay in computer simulation, an equivalent head loss coefficient C L was introduced for both the method of characteristics and the implicit method. After calibration, the equivalent head loss coefficient C L was determined for the present experimental setup. Furthermore, computer simulations using the equivalent head loss coefficient and experiments for transient flow regarding backflow preventer in a pipe were conducted.
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Kwon, H.J. Head loss coefficient regarding backflow preventer for transient flow. KSCE J Civ Eng 12, 205–211 (2008). https://doi.org/10.1007/s12205-008-0205-y
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DOI: https://doi.org/10.1007/s12205-008-0205-y