空调贯流风扇转子振动对支承轴承受力及寿命影响

Influences of Vibration of Cross-Flow Fan Rotor on the Load and Lifetime of Supporting Bearing in Air Conditioner

以空调贯流风扇转子支承轴承为研究对象,通过对贯流风扇转子及轴承的力学分析,建立了贯流风扇转子支承轴承的滚子受力计算模型.通过对转子的结构分析,进行集总质量离散,建立了对这种特殊结构的转子振动性能进行数值计算的模型.结合滚动轴承疲劳寿命计算方法,建立了考虑转子振动时支承轴承疲劳寿命的计算模型.针对具体算例开展研究的结果表明,考虑与不考虑贯流风扇转子振动时支承轴承受力及疲劳寿命具有明显差异.在考虑贯流风扇转子振动条件下,研究了贯流风扇转子转速、转子长度以及风扇叶片数目对支承轴承滚子载荷和疲劳寿命的影响.发现随着转速的增大,贯流风扇转子长度的增加以及风扇叶片数目的增加,轴承滚子所受载荷增加,轴承寿命下降.

In this paper, the supporting bearings of the cross-flow fan rotor in the air conditioner are studied. Upon the mechanical analysis of the cross-flow fan rotor and the bearing, a calculation model is established for calculating the roller load of the supporting bearings in the cross-flow fan rotor. Upon the analysis of the structure of the rotor, the lumped mass discretization is carried out, and a numerical calculation model for the vibration performance of the special rotor is established. Together with the calculation method of the fatigue lifetime of the rolling bearing, a calculation model is established to calculate the fatigue lifetime of the supporting bearing with taking the rotor vibration into account. Through a numerical simulation for a specific example, it is found that the roller load and fatigue lifetime of the supporting bearings show strong dependence on the case whether the vibration has been taken into account or not. The influences of the rotor rotation speed, the length of the rotor and the number of fan blades on the roller load and fatigue lifetime of the bearings are studied with considering the vibration effects of the cross-flow fan rotor. These effects can be seen from the simulation results. With the increase in the rotation speed, the roller load of the bearing is increased, while the lifetime of the bearing is decreased. Similar influences are observed in the cases of increasing the length of the fan rotor and the number of fan blades.