畜禽垃圾螺旋挤压脱水过程数值模拟研究

Numerical Simulation Study on Spiral Extrusion Dehydration Process of Animal Waste

为探究畜禽垃圾在螺旋挤压脱水过程中压力与液相体积分数的变化情况,根据畜禽垃圾的处理需求,课题组设计了连续螺旋和间断螺旋2种结构的挤压螺杆。通过计算流体力学的方法,对不同工况下的畜禽垃圾的挤压过程进行数值计算,研究了影响挤压脱水效果的主要因素;并通过试验验证了数值计算的可靠性。结果表明:间断螺旋对挤压过程有良好的促进作用,畜禽垃圾螺旋挤压脱水主要影响因素影响程度由大到小次序为螺杆转速、入料液相体积分数和入料粒径。该研究可为后续螺旋挤压机挤压螺杆的结构优化提供参考。

In order to explore the change of pressure and liquid phase volume fraction in the process of spiral extrusion dehydration of livestock and poultry waste,two kinds of extrusion screws,continuous screw and intermittent screw,were designed according to the treatment requirements of livestock and poultry waste.Through the computational fluid dynamics method,the extrusion process of livestock and poultry waste under different working conditions was numerically calculated,and the main factors affecting the effect of extrusion dehydration were studied.The reliability of numerical calculation was verified by experiments.The results show that the intermittent spiral has a good promoting effect on the extrusion process,and the main influencing factors for the dehydration of livestock and poultry waste by spiral extrusion in descending order are screw speed,feeding liquid phase volume fraction,and feeding particle size.The research can provide reference for the structural optimization of screw in subsequent screw extruders.