Design And Performance Research Of The Uniaxial Double-transport Low-specific-speed Centrifugal Pump

The low-specific-speed centrifugal pump has been widely used to transport high head and small capacity medium in most industrial fields such petrochemical industry, tragacanth, pharmaceutical industry. In this paper, a new structure of centrifugal pump named the uniaxial double-transport centrifugal pump has been brought forward. Hydraulic, integral structure and performance research have been carried out to study the uniaxial double-transport low-specific-speed centrifugal pump. The uniaxial double-transport centrifugal pump has two flow passage components, can transform two medium in parallel. Both of the numerical simulation and experimental are adopted to study the uniaxial double-transport centrifugal pump, to comprehend the internal flows and external characteristic and to provide reference for optimization design of centrifugal pump. The main contributions of this thesis are as follows:(1)The methods of hydraulic design and integral structure have been presented to design the uniaxial double-transport centrifugal pump, the flow passage components of uniaxial double-transport centrifugal pump has been designed by using the method of complex impeller .(2) The methods of numerical simulations have been introduced. The Pro/Engineer software is applied to model the flow passage components suction chamber, complex impeller and spiral case. The structural mesh was generated by using NUMECA software。(3) The Navier-Stokes equations and the Spalart-Allmaras turbulence model are carried out to simulate one side inner flied of the uniaxial double-transport centrifugal pump, The frozen rotor approach is adopted between the impeller and the volute to transform the coupling information of flow fields. The distributions of velocity and pressure are obtained, and the properties of inner flow inside the volute are also analyzed. At last, the performance curves were forecasted through numerical simulations.(4) Experimental study was carried out to the uniaxial double-transport centrifugal pump by determine experimental scheme and set up testing rig. Through the experimental research the rationality of the design method of the uniaxial double-transport centrifugal pump was verified. The accuracy of our numerical models and the reliability of the performance prediction were further verified by comparing numerical calculation results, and all these could be references for the performance optimization of the centrifugal pump.