Numerical Simulation of Flow Pressure Drops for Complex Pipe Segment

To study the causes for the local pressure drop,the three-dimension single-phase flow in the complex pipe segment with holes in nuclear power plants was studied with the computational fluid dynamics method under two flow conditions. The hybrid grids technique and standard k-ε turbulence model were applied. The results show that the different forms of pressure drop were caused by different flow directions in the pipe; the local stream line resulting in eddy and pressure changed greatly near the porous liner tube; how and where the cross-sections of flow channel change corresponding to the certain flow direction cause mainly different local pressure drop.