离心机风阻功率及启动过程分析

摘要

ABSTRACT:Objective To study the wind resistance power and the starting process of centrifuge. Methods Targeting at the centrifuge which was operated in the cylindrical chamber, the arm moment and the friction moment applied to air were analyzed. Based on the moment of momentum theorem and the linear distribution assumption of air flow field, the equation of air flow ratio was deduced. Then, the explicit expression of air flow ratio was proposed, thus, the calculation formula of wind resistance power was derived. Results The functional relationship of the centrifuge angular velocity and the wind resistance power with time was deduced in the condition of constant starting torque of centrifuge. Based on the principle of energy conservation, the temperature rise of air was evaluated in the chamber. Conclusion Based on the design parameters of the centrifuge, this study proposed the time-angular velocity curve and the time-wind resistance power curve. The results of this study can be used as the theory basis in the centrifuge engineering design.%目的：研究离心机的风阻功率和启动过程。方法针对圆柱形机室内运行的离心机，分析机室内空气承受的悬臂力矩和摩擦力矩，基于动量矩定理和流场的线性分布假设推导随流比方程，给出随流比的显式表达式，继而导出离心机风阻功率的计算公式。结果针对恒扭矩启动条件，得到了离心机角速度和风阻功率随时间变化的函数关系；基于能量守恒原理，得到了机室内的空气温升。结论基于离心机的设计参数，给出了角速度和风阻功率的时间变化曲线。通过该项目的研究，为离心机的工程设计提供了理论依据。