... ] studied transient flow in conduits with expanding or contracting cross section. In these cited studies, the most popular method for solving transient equations was used, i.e., method of characteristics. Meniconi et al. [ 3 ] analyzed the interaction between pressure waves with sudden changes of cross...

... turbulence vortices transient flow radial flow pump stopping period dynamic mesh VOF As turbomachines are widely used in modern society, various transient operations of radial flow pumps have received extensive attention. A quasi-steady assumption is acceptable in the case of slow changes...

...Chenzhou Lian; Dmytro M. Voytovych; Guoping Xia; Charles L. Merkle Numerical simulations of the transient flow of helium injected into an established background flow of nitrogen were carried out to identify the dominant features of the transient mixing process between these two dissimilar gases...

... turbulence transition to turbulence constant acceleration flow turbulent slug transient flow large-scale pipeline An abrupt transition from laminar to turbulent flow in start-up accelerating pipe flows is a common feature. Transition to turbulence is delayed...

... . The main findings obtained in this study can be summarized as follows. 1 A newly developed unsteady flow generation system was able to precisely produce the transient flow with a programed cross-sectional mean velocity. 2 The initiation of a turbulent slug was suppressed, as expected, while the flow...

...-coupling computation. The proposed method makes the computation processes more close to the real conditions. Relations between the instantaneous flow evolutions and the corresponding transient flow-rate, head, efficiency and power were analyzed. Relative velocity comparisons between the transient...