微机床主轴用微涡轮设计及其气动性能研究

设计计算了微机床主轴用微涡轮的结构及其气动性能,采用FLUENT软件对微涡轮内的高速气流进行了数值模拟.分析结果表明:供气压力一定,微涡轮因气流压力产生的转矩随转速的变化不大,而因气流黏性产生的转矩随转速的提高大幅度减小,从而造成总转矩减小.微涡轮室内的背压力随供气压力的提高而增大,严重影响了微涡轮转速的提高.微涡轮喷嘴流出的气流未直接流向与其对应的叶片上,而是在涡轮室内来流的作用下绕叶轮流动,气流损失较大.最后对微涡轮的结构进行了改进,转矩提高了13%,达到了设计要求.

Design of the Micro-turbine for the Micro-machine Tool Spindle and Research on Its Aerodynamic Performance

The structure and aerodynamic performance of the micro-turbine for the micro-machine tool spindle were designed and calculated,and the high speed airflow in the micro-turbine was numerically simulated by the software FLUENT.The analysis has indicated that the micro-turbine torque produced by airflow pressure changes little while that by air viscosity decreases dramatically with the increase of rotational speed at constant supply pressure,which causes a dramatic decrease in the total torque.The back pressure in the micro-turbine chamber increases with the increase of the supply pressure,which seriously affects the rotational speed.The airflow from the micro-turbine nozzle cannot directly go to the corresponding blade,but goes round the blade wheel under the action of the coming flow,which causes great flow loss.Finally the micro-turbine structure was improved and its torque increased by 13%,which satisfied the design requirement.