离心压缩机轴承总成气相流动与温度场特性

基于高速运转过程中的离心压缩机轴承总成腔体内部摩擦产生大量的热导致流场内部温度过高的问题,本文对离心压缩机滚动轴承总成中的制冷剂气体流动和换热特性进行了研究。以6009深沟球轴承组为对象,建立了轴承总成内腔的数值分析模型。分析了轴承运动对流场内部气相流动的影响,并对比不同转速下内部温度场情况,揭示了转速对轴承总成腔内的传热特性的影响。结果表明：轴承旋转引起了旋转流,所带来的能力增加了流速,且使轴承总成内部的压力升高；随着转速的增大,流场的流速随之增加,轴承腔内的温度会有一定程度的降低,但转速继续升高,摩擦损耗急剧增加,产生的热量大于气体的换热能力,温度随之升高,最终得出较好的散热工况下的转速。

Investigation of Gas Flow and Temperature Field Characteristics in The Bearing Assembly of A Centrifugal Compressor

In order to design machine tool rapidly, Research on the definition method of user defined feature, which are restricted by Feature-based constraints. It provide the unique discretional method for features, finally built the commonly UDF library of machine tool. Combine with Pro/ENGINEER secondary development package Pro/toolkit, the UDF information could be accurate extracted and reused, develop the UDF feature library system. It provides advanced rapid design tools for machine tools and other products for three-dimensional design, improve design efficiency and lay the founded of computer-aided design. The internal friction of the bearing assembly of centrifugal compressor during high-speed operation generates a lot of heat, which leads to the problem of excessive temperature in the flow field. In this paper, the flow and heat transfer characteristics of refrigerant gas in the rolling bearing assembly of centrifugal compressor are studied. Taking angular contact ball bearings 6009 as research objects, a numerical analysis model for the inner cavity of bearing assembly is established.By comparing the internal temperature field at different rotational speeds, the effect of rotational speed on the heat transfer characteristics in the bearing assembly cavity is revealed. The results show that rotation of bearings causes rotational flow, which increases the flow rate and increases the pressure inside the bearing assembly. With the increase of rotational speed, the velocity of flow field increases and the temperature in bearing chamber decreases to a certain extent. However, as the speed continues to rise, the friction loss increases sharply, the heat generated is greater than the heat transfer capacity of the gas, and the temperature increases accordingly. Finally, the speed under better heat dissipation conditions is obtained.