Study on the Hydraulic Performance of Elbow-Inlet Passage by CFD

The Elbow-inlet passage with low loss and little width is a typical passage of pumping station. A new optimization criterion for hydraulic design is put forward. The incompressible N-S equations are solved by the finite volume method. Base on the RNG k-ε model with Wall-Function Law, the SIMPLEC algorithm is applied for the solution of the discretization governing equation. Using CFD, the flow pattern in passage is revealed. The flow patterns in the elbow-inlet passage are classified as three patterns phases: horizontal contraction, elbow bend and vertical phase. According to axial velocity of ten sections, the new criteria of named height of pump (NHP) and other control parameters for Elbow-inlet passage is suggested. A good agreement is achieved between the numerical simulation and experimental results. The computational model is much more effective for hydraulic performance study. The optimum hydraulic design method was established: First, the shape of passage is designed on the optimum control parameters. Second, the sections of passage are designed according to the smooth average velocity. Finally, flow patterns are studied in order to find its hydrodynamic characteristics. This method could simply the design of Elbow-inlet Passage.