Numerical Simulation Study On The Hydrodynamic Characteristic Of Airfoils Of Axial-flow Pump

With the development of economy , axial flow pump plays an important role in many production department of our country. Axial flow pump has been widely used in the city and township water supply projects and flood and drought control project. Now when people design impeller,they frequently had reference to the airfoils of Aeronautics and Astronautics. People have carried out a large number of airfoil researches in the area of Aeronautics Astronautics and Fan, but there is little research about hydrodynamic characteristic of axial-flow pump's airfoils.The hydrodynamic characteristic of axial-flow airfoils not only has a direct influence on the cavitations'performance and range of operating of axial flow pump,but also has a direct impact on the efficiency safety and reliable operation of pumping station. Tunnel experiments is a common method which needs more fund and time,to a certain extent, this has held back the development of airfoil. With the development of computer technology and CFD technology, methods of numerical simulation have been used more and more widely in flow simulation. Therefore, the mathematical simulation models about several airfoil sets of axial flow pump were established in this paper and software the FLUENT was used to get numerical calculation result.In this paper, Gambit was used to create geometry and generate mesh of airfoil. There are three types of turbulence models and methods about coupling of pressure and speed are given in FLUENT, we will get a more suitable and reliable method for calculating the flow around airfoils. Through numerical simulation and the comparison of known characteristics of the airfoil, the RNG k ?εmodel is probed to be an appropriate method in this paper. The computational results indicate the feasibility of the numerical simulation methods which was used to research airfoils.Through the numerical simulation, the drag and lift coefficient of airfoil, the best ratio of lift to drag can be got, as well as pressure distribution of airfoil due to the flow around airfoil. Two aspects were studied in this paper. First, we studied on generating S-style airfoil from a common airfoil whose hydraulic performance is better, Through numerical, the performance about lift and drag, pressure distribution around the of NACA66-mod, S airfoil can be got, the reasons were analyzed why there were differences between theses two airfoils hydraulic characteristics, Second, a new method was discussed in this paper, by which a series of airfoil through rotate front airfoil in different angle can be got, After numerical calculation about series of airfoil, a variety of airfoil drag and lift coefficient and the optimum coefficient of lift to drag were got , By comparing the optimal angle of attack airfoils lift and drag coefficient and pressure distribution, the new airfoil's lift coefficient is higher than the original airfoil's. Lift coefficient increases when the head of airfoil rotating Angle increases. But because the drag coefficient increases too, the coefficient of lift-to-drag does not increase in the same time. By comparing several results we can get the best airfoil of hydraulic performance in these airfoils. In this paper, the results of these researches are useful for the hydrodynamic characteristics research of axial flow pump airfoil and the design of pump impeller.