Abstract
Conducting a direct numerical simulation, we analyzed the flow in a symmetrically bifurcated Y-shaped channel having a high aspect ratio rectangular cross-sectional area. The channel could be considered as a combination of an introduction channel, an expansion part and two bifurcation channels. In the region near the expansion original point, the pressure gradient and the velocity in the main flow direction increase. The distance between the expansion original plane and the bifurcation original plane along the side wall is shorter than that along the center line, so that the pressure in the expansion direction side area is greater than that in the bifurcation point side area on the bifurcation original plane. The expansion and the bifurcation of the channel make the velocity profile and the pressure distribution on the bifurcation original plane, and the pressure gradient restores the velocity profile to be fully developed.