Computer And Inner Flow Numerical Simulatiom Of Double-volute Casing

Centrifugal pumps are hydraulic machines which are used in industrial and agricultural produce. The double-volute is the importance flowing parts that Centrifugal Pump, after being located on a impeller. The main function be to collect to liquid come out from the impeller, and make the fluid's speed converting into the pressure. Especially can better dispel radical force that Impeller produces while Centrifugal Pump working on off-design, and keep a impeller the stability of the work, raise the credibility of pump. Double-volute's good and bad of design will directly influence the whole function of pump.This topic make use of computational fluid dynamics(CFD) method, carry on an numerical simulation in a double-volute then analyse its result detailedly. With the model pump (CB2010/100) for example, according to the K-8 theories, choose to use Mixture model, make use of the UG software set up 3D models of Double-volute, then the body-fitted coordinate systems and the tetrahedron grid systems are applied to establish grids for calculate. Finally make use of fluent to carry on 3D inner flow the number emulation of field. Got to the distributing of parameters, such as speed and pressure, analyzed the characteristic of the Centrifugal Pump's inner flow.The subject take liquid flow as the medium, the algorithm of SIMPLE has used to correct of the pressure. After setting different boundary conditions , the physical models are computed in K-εmodel. And computed single-volute and double-volute's inner turbulent flow in three typical works (such as 0.8Q, 1.0Q and 1.2Q). According to the speed field and the pressure distributing that has got in three different work, Analyzed the volute's internal hydraulic characteristic, then compared the differentiation that the same volute under the different work conditions and single-volute ,double-volute in the same work condition. After computed number of the single volute and double-volute inner turbulent flow, got following important conclusion:1. Under the standard work condition, the double-volute can more remove radial force, can also more and very convert the kinetic energy of liquid as pressure ability, make the volute inner liquid flow be getting more even, reduce the water power loss. Have no back flow phenomenon in nose. 2. In the 0.8 Q, the same is that single-volute and double-volute both can clearly lower speed, and reduce water power loss. Different is single volute internal pressure dissymmetry, as a result will influence a pump the function of the movement; But double-volute can ideally cancel radial force and increase the stability of pump's movement.3. In the 1.2 Q, the pressure of the single volute and the double-volute distributes to differ very greatly, single volute can't the enough nicely balance radial force, but double-volute can obviously removed the radial that leaf to lead to and raised the credibility and stability of pump.