The Design Research On Water Pump Impeller Based On The Technology Of CFD And RP

The power consumption of various pumps accounts for 20.9% of the total electric power consumption in our country every year, in which the amount of centrifugal pump is large and the scope is wide, and it is widely used in agriculture, petrochemical, aerospace, mining and other fields. Because the complexity of the impeller structure in the centrifugal pump causes the complex inner flow state of the centrifugal pump, the research on internal flow of centrifugal pumps and the optimization design of major structural components have great significance for improving the performance and efficiency of the centrifugal pumps, avoiding running the pump in the bias conditions. This paper proposes to combine the calculate fluid dynamics (CFD) method with the laser rapid prototyping (RP) method aiming at the multi-stage centrifugal pump of 20B4, which reduces the time of new pump largely from design to finished product, and this provide a new production method for manufacturers.This paper based on the traditional centrifugal pump-design methods and modern CAD design technology, created the three-dimensional modeling of one stage of the 20B4 multi-stage centrifugal pump by the three-dimensional modeling software of Solidworks, which included the flow region of import channel, impellers, guide vanes and exit routes, and then lead the physical model into the software Gambit to unstructured mesh, finally, we made corresponding adjustment to the grids, so the model smooth with no dead pixels .This paper has calculated the numerical simulation of whole flow field in nine working conditions under different flow by application of commercial CFD software Fluent. We imitated the total pressure distribution, the static pressure distribution, the vector graph of relative velocity and absolute velocity in rated conditions, simulation results show that the flow field has a uniform distribution without the phenomenon of inverse flow and wake, for instance ,the inverse flow occurs at the entrance, and wake occurs in some flow passage but less obvious. From the performance prediction of the simulation results, we get the relationships between pump head, shaft power, efficiency and flow, and find the disciplines that the pump head decreases with increasing flow and the efficiency first increases and then decreases with the flow. Comparing the characteristic curve from intimating the centrifugal pump with the experiment’s by consideration of the Mechanical loss and volume loss, we find that they have a relatively agreement with each other, and it has verify the reliability of simulation.The manufacture of powder impeller was done from the impeller model by using the powder-sintering rapid prototyping equipment, then the production of resin impeller. From the experimental test of the resin impeller, we can find that the centrifugal pump working stability and it has a better performance from the experiment result, which verified the reliability and feasibility of replacing the experimental pieces by resin impeller.