The Dynamics Numerical Study Of Centrifugal Pump Based On Fluid-solid Interaction

Centrifugal pump is a kind of common fluid machinery, and it plays a very importantpart in the actual industrial production, in particular, in metallurgy, petrochemical industry,urban water supply, delivery of natural gas, and agricultural irrigation. In actual operation,there exists Fluid Structure Interaction between the centrifugal pump internal flow field andthe impeller. If FSI is considered, the numerical simulation can reflect more realistically theflow field characteristics of centrifugal pump. In this paper, it is analyzed that the steady,transient and Fluid Structure Interaction numerical simulation of a centrifugal pump, fromwhich the distribution of pressure and velocity at centrifugal pump blades, impeller and volutecan be showed. Numerical simulation of a centrifugal pump offer data for the furtheroptimization design of centrifugal pump.The main works are as follows:1. On the basis of full understanding of Fluid Structure Interaction definition, researchstatus, data transfer methods at the Fluid Structure Interaction surfaces and so on, a detailedsimulation of the internal flow field is conducted by the software ANSYS-Workbench.2. In the steady simulation, κ εturbulence model are used to simulate internal flowfield. According to simulation in the design condition and off-design conditions, we can getthe pressure, total pressure and velocity distribution of the internal flow field. The centrifugalpump performance curves predicted by the simulation results agree with experimental curves.3. Take steady analyze results as initial conditions, the centrifugal pump transientsimulation are completed by the sliding mesh model. According to the transient simulation,the pressure and velocity field variation during a blade period can be get, which is thepressure and velocity are the minimum when the blades just turns to the tongue, and reachtheir maximum until the blades across the flow channel middle surface.4. Bi-directional solution process of the structure field and fluid field is established bytransient structural module and CFX in ANSYS Workbench，from which the velocity fieldand pressure field change before and after the Fluid Structure Interaction at the designcondition is also obtained. Spectral analysis on the pressure are analyzed．The results indicatethat，the pressure pulsation frequency is the blade passing frequency of approximately343Hzat design condition and high flow conditions and the dominant pressure pulsation frequency is98Hz which less than1times blade passing frequency at small flow conditions.