| The vortex pump is one kind of non-clogging pumps. It has been widely applied in the chemical engineering, the mine, urban draining and the other fields. The flow in the vortex pump is very complicated and the flow mechanism in vortex pump is not well understood, so the design theory of vortex pump is not perfect. Many examples in applications are based on the common water pump design theory, improved by the experience in application. The efficiency of the common vortex pump is low. In order to improve the performance of the vortex, it is necessary to investigate the flow field in the vortex pump and understand it well.With the rapidly development of the computer technique and the calculation fluid dynamics (CFD), the inner flow of the hydraulic machinery has been widely and deeply investigated, which has been being one of the studying hot spot. The pump performance can be predicted and the structure can be optimized by using CFD to calculate the flow of a pump, observing and analyzing interior flows.In this dissertation, the vortex pump of JFZ65-310 in some company has been taken an example, and the geometric modeling has been made by Pro/E. The inner flow has been simulated by using Fluent software, according to the Reynolds Average N-S equation and standard k-εturbulence model with pressure-velocity connection algorithm SIMPLEC.The main research of the vortex pump and the achievement are as followings:(1) The Pro/E software of three-dimensional modeling has been used for the three-dimensional modeling for the pump and the Gambit software has been used for the unstructured meshing of the inner flow channel of the pump region.(2) The external characteristics and the distribution of speed and pressure has been calculated when the media is water. The calculation results are agreement with those of the experiment. The results of the velocity field indicate that the circumferential velocity reaches the maximum at the 0.7 times of impeller radius, and then begins to decrease. The negative axial velocity appears near the 145mm along the radial position which indicate the fluid is outflow from the impeller. The results of the pressure distribution indicate that the pressure increases along the radial direction. (3) The pump head and efficiency decrease as the particle diameter increasing when the density of particle is 2500kg/m3 and the volume concentration of particle is 5%, but the power decreases as the particle diameter increasing. The pump head decreases by about 1.7m, and power increases by about 1600W, and efficiency decreases by about 8% when the diameter is 2mm.(4) The pump head and efficiency decrease as the particle volume concentration increasing when the density of particle is 2500kg/m3 and the diameter of particle is 2mm, but the power decreases as the particle volume concentration increasing. The pump head decreases by about 4.8m, and power increases by about 3500W, and efficiency decreases by about 15% when the volume concentration is 15%.(5)The pump head and efficiency decrease as the density increasing when the particle volume concentration is 5%and the diameter of particle is 1mm, but the power decreases as the density increasing. The pump head decreases by about 1.6m, and power increases by about 1400W, efficiency decreases by about 8% when the density is 2500kg/m3.(6) The internal flow, pressure and particle distribution of pump has been studied as to the solid and fluid two-phase medium. The results indicate that the distribution of solid particle is small on the short blades and non-working face of long blades, but more on the corner of face of the long blades. The distribution of the solid particle is almost uniform in the non-leaf cavity.(7) The pump head decreases by about 3.5m, and power increases by about 3450W, efficiency decreases by about 14% when the phosphate is pumped. As to phosphate, the kinematical viscosity is 0.001218 m2/s and the density is 1250kg/m3 when the temperature is 80℃. |
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