Study on Two-Direction Suction Passage of Pumping Unit in Cooling System of Power Plant

Abstract

A special vertical pumping system was designed for cooling system of a power plant. In order to study flow pattern and hydraulic performances of vertical pumping system with bell inlet and symmetric volute outlet, especially the flow fields in the suction passage of pumping system, the incompressible N-S equations are solved by the finite volume method. Base on the k-ε model with Wall-Function Law, the SIMPLEC algorithm is applied for the solution of the discretization governing equation. Using multiple reference frames, solutions of the flow fields of whole vertical pumping system at a Reynolds number of more than 113,000 for flow in the pumping system are presented. The normal height of pumping system is put forward. The hydraulic performances of pumping system at the different operating points near to the Best Efficiency Point (BEP) were predicted. A model pumping system was designed to test the performances of the system and the measurements of velocity distribution in outlet section of the suction passage were taken. The velocity distribution of measurements and the velocity distribution of computation in outlet section of suction passage show an asymmetrical flow field even under the operation at BEP. In general the hydraulic condition of suction passage can meet the requirements of pump operation. The differences between the computational results and the measurements results are discussed.