Mobile QR Code QR CODE : Journal of the Korean Society of Civil Engineers
Title A Study on The Velocity Distribution in Closed Conduit by Using The Entropy Concept
Authors 추태호 ; 옥치율 ; 김진원 ; 맹승진
Page pp.357-363
ISSN 10156348
Keywords Chiu"s equation;mean velocity;entropy M;conduit;Chiu의 공식;평균유속;엔트로피 파라미터 M;관수로흐름
Abstract When yields the mean velocity of the closed conduit which is used generally, it is available to use Darcy Weisbach Friction Loss Head equation. But, it is inconvenient very because Friction Loss coefficient f is the function of Reynolds Number and Relative roughness (ε/d). So, it is demanded more convenient equation to estimate. In order to prove the reliability and an accuracy of Chiu"s velocity equation from the research which sees hereupon, proved agreement very well about measured velocity measurement data by using Laser velocimeter which is a non-insertion velocity measuring equipment from the closed conduit (Laser Doppler Velocimeter: LDV) and an insertion velocity measuring equipment and the Pitot tube which is a supersonic flow meter (Transit-Time Flowmeters). By proving theoretical linear-relation between maximum velocity and mean velocity in laboratory flume without increase and decrease of discharge, the equilibrium state of velocity in the closed conduit which reachs to equilibrium state corresponding to entropy parameter M value has a trend maintaining consistently this state. If entropy M value which is representing one section is determinated, mean velocity can be gotten only by measuring the velocity in the point appearing the maximum velocity. So, it has been proved to estimate simply discharge and it indicates that this method can be a theoretical way, which is the most important in the future, when designing, managing and operating the closed conduit.