Modeling And Simulation Research On Grain Fluid Motion Of Assembled Axial-Flow Device

On the base of summarizing and analyzing the existing state of domestic and foreign research, through the comprehensive method of theory analysis and simulation research, study on the mechanism and parameters of the assembled plank-tooth and helical vanes axial-flow threshing and separating device. Grain in the axial space is regarded as fluid, ananlyze the physical properties of grain fluid by experiment, determine the motion velocity of grain fluid by high-speed photography, analyze the threshing principle and process, establish hydrodynamic model and simulate about the grain fluid, which lay a solid foundation for the development of modelmachine.1. Obtain distribution curves and regression equations of grain fluid's density along axial under different feeding rate in the threshing and separating space. Approximate determine the viscosity of grain fluid by research finding of predecessor and obtain the regression equation about viscosity and density.2. Observe and analyze the motion condition of free kernels, short straws, medium length straws and integral motion of grain fluid by high-speed photography, obtain the motion velocity of grain fluid under different cylinder's rotating speed.3. Introduce the assembled plank-tooth and helical vanes axial-flow threshing and separating device and threshing and separating principle, analyze the threshing and separating process. Establish hydrodynamic model about grain fluid by Navier-Stokes equations, determine the boundary condition of model.4. Intorduce COMSOL Multiphysics, simulate the hydrodynamic model and analyze the simulation results.5. Analyze the influence of the main factors on motion of grain fluid and performance indexes, obtain the more reasonable factor value when the grain fluid is regarded as fluid. Verify the simulation results by high-speed photography techniques.