INFLUENCE OF DIFFERENCE IN FLUID VISCOSITY ON OPEN CHANNEL FLOW WITH BRIDGE PIER

Abstract

 Since the bridge piers in the river channel generate local flows, they may cause disasters. In addition, it is necessary to clarify the flow mechanism of high-concentration currents with piers in consideration of the occurrence of high-sand-containing rivers such as the Yellow River and flows containing a large amount of fine sediment during heavy rains. Therefore, in this study, we investigated the average flow characteristics and momentum transport characteristics when the viscosity was changed using an aqueous solution of sodium polyacrylate (PSA) in an open channel flow with oval bridge piers. As a result, it was clarified that the detour flow near the tip of the bridge pier and the flow toward the center of the channel near the downstream of the bridge pier are suppressed as the viscosity increases. Regarding the momentum transport characteristics, it was clarified that the momentum transport due to turbulence is extremely suppressed compared to advection due to the increased viscosity.