叶片式抛送装置气流流场数值模拟与优化

Numerical Simulation and Optimization for Air Flow in an Impeller Blower

应用计算流体力学软件Fluent对9R-40型揉碎机叶片式抛送装置内部的三维气流流场进行了数值模拟,并对计算出的出料直管处的气流速度与试验值进行了比较,检验了数值模拟的可靠性。同时,对其叶片数、叶片倾角、抛送外壳形状及出口处倒角等几何参数的不同变化作了对比模拟,得出4叶片、圆形外壳、后倾叶片更有利于抛送,且出口处圆弧半径不宜太大。

Poor air flow patterns and vortices can affect the efficient flow of forage. To improve the working efficiency of an impeller blower, the 3 - D air flows in the impeller blower of a 9R - 40 rubbing and breaking machine was numerically simulated and analyzed with computation fluid dynamics （CFD） software Fluent 6. 3. Then the numerical simulated results of air flow velocities in the blowing pipe were compared with their testing results to validate the reliability of the numerical simulated results. At the same time, some main geometrical parameters were simulated, which included the numbers of blade, the mounting angle of blade, the shape of housing and the are-radius of outlet of housing etc. The optimum results were obtained according to the simulated results. The study results showed that with 4-blade, blades slanted backwards, and circular housing, impeller blowers produced more efficient air flow respectively than impeller blowers with 3-blade, blades slanted forwards and radial blades, and non-circular housing.