摘要：The instantaneous variations of the hydraulic characteristics take place in centrifugal pumpsduring...The instantaneous variations of the hydraulic characteristics take place in centrifugal pumpsduring their start-up, shutdown and other variable speed operations. In this paper, the variable speedmethod was proposed to simulate the transient internal flow field and the external performance of thepump during starting and stopping periods. The terms of accelerations due to variable speeds in the flowgoverning equations were analyzed in a multiple reference of frame （MRF）. A transient CFD simulationwas performed for a typical centrifugal pump by using ANSYS-CFX with the standard k -6 turbulencemodel. The entire simulation process was composed of four stages ： start-up, normal run, shutdown andpost-shutdown. The function of rotating speed with regard to time was set by CEL language directly intothe impeller domain in the pre-processor of the software to conduct variable speed simulation. The varia-tions of the flow field in the centrifugal pump were obtained from the transient simulation. The changinglaws of flow rate, head and other performance parameters over time were also analyzed and summarized.显示全部
