Massive Numerical Simulation In A Submersible Axial Flow Pump

Submersible axial flow pump has the high specific speed in the kind of the vane pump,mainly used in place of large capacity and low-lift, it has been widely used in each domain of national economics because of its installation and operation convenient.The internal flow is relatively complicated,usually the main research method on axial flow pump is based on the experiment, but because of its work under rotation,so the internal flow field measurement is difficult. With the development of computer technology,the numerical simulation is the most popular method to further study the axial flow pump at present. There are a variety of numerical simulation software can be used for the axial flow now,and each software also have different characteristics, but the size of the mesh, efficiency and precision of the solver and the different turbulence model has the certain effect on calculation results.Based on the QZ700type, FLUENT is used to deal with the steady simulation for the mesh model in three different densities,Compared the calculated results by the same software under different grid.The unsteady simulation method is employed with the two turbulence model respectively, Compared the analysis results of different turbulence models.Finally,it use different density and turbulence for unsteady numerical simulation,Compared the different grid density under unsteady analysis results.The following results can be get below:1、ICEM software is used here to give unstructured grids of three different numbers, and they are approached respectively into FLUENT to compare with the calculation results. The conclusion is that the more accurate the grids are, the more close the calculation is to the test. The discussion about the independence of the meshes is only suitable for the engineering. But the increasing grids that can lead to more accurate and careful analysis for the pump flow field in numerical simulation.2、In FLUENT, the Spalart-Allmaras and SST k-omega turbulence model are used to do the simulation. From the results it can be discovered that k-omega model supplies a more accurate calculation than Spalart-Allmaras model and the former are more close to the real flow. The difference of the calculation appears by comparing the pressure fluctuation and clearly the unsteady results are more accurate than the steady results.3、FLUENT is used to deal with the unsteady simulation for the mesh model in two different densities, the conclusion is that the more accurate the grids are, the more close the calculation is to the test. Although the calculation results is tending towards stability after increase the number of girds, the results are different, so we should increasing the grid density as far as possible.