Research On Cleaning System Used On Plot Wheat Seed Combine Harvester

The numerical simulation on the cyclone separating cleaning system used on plot wheat seed combine harvester has carried out by using the commercial CFD software-FLUENT in this thesis. RNG k ?εturbulence mode was used to simulate the gaseous phase because of the strong turbulence of gas, Pressure-velocity coupling with non-staggered grid SMPLEC algorithm, Discretized with the QUICK format, Pressure gradient can use PRESTO format. the Lagrange equation-based DPM (Discrete Phase Mode) was used to track the particles' motion.The simulation results:Get cyclone cylinder internal air velocity distribution, pressure distribution and the particle trajectory,The results showed that the flow field in a gas cyclone separator could be divided into two parts: the inner one and the outer one. the distribution of velocity and pressure took on the basic axisymmetrical。Pressure field from the axial part of the low pressure area and the high pressure zone formed around the ring;Velocity field from the axis part of the high-speed zone and the cylinder wall, low-speed zone around the ring formation。This paper designs three kinds of structural forms of cyclone tube,Use the same mesh,boundary conditions and numerical calculations,In three models of the hull separation efficiency, separation efficiency and stem the loss of wheat grain was compared and analyzed evaluation,To effect a relatively better method for further study。As the impact of cyclone separation efficiency cleaning system, the complexity of factors,In this study, only feed rate, negative pressure suction blower, cyclone separator tube length and the entrance cone size for the study of four major factors,Arrangements for the use of 16 sets of orthogonal design of numerical simulation,comparative analysis,Optimization of overall balance combined with a team of excellent programs:Feeding speed:12m/s;Negative pressure suction fan:-1250pa;Cone part of the length:150mm;Entrance size:120x150mm2。Optimization scheme based on orthogonal test,set up cyclone cleaning system test bed with " plot wheat seed combine harvester prototype".Not consider the length of cyclone tube and the size of inlet on cleaning performance,Only consider the rotate speed of catching impurity fan and rotate speed of winnower which have more evident effects on the cleaning performance. In the near optimization program based on orthogonal test, Arrangement of secondary general rotation test,Establish cleaning system cleaning performance-cleaning rate and cleaning grain loss rate model. Determine the optimal structure parameters and motion parameters,and calculate the optimum design,Analysis of the structure and motion parameters on the cleaning performance of law。...