时变条件下滑动轴承系统的多物理场耦合分析

Multi-Physical Field Coupling Analysis of Journal Bearing System under Time-Varying Condition

针对传统非耦合分析方法无法研究轴颈、油膜与轴瓦之间的相互作用以及普通流-固耦合方法无法真实反应轴承运转工况的问题,提出了一种融合计算流体动力学、流-固耦合和热流耦合的瞬态分析方法,分析了时变条件下轴承系统速度、压力和温度的多物理场耦合,并分析了空化现象的影响,精确计算了恒定载荷下的偏心率和温升场,以及从启动到稳定过程的轴心轨迹.同时,分别考虑腔结构、轴颈转速和载荷对油膜压力、偏心率、温升和气穴的影响,并将计算结果与相关文献的实验结果进行比较.结果表明:所得计算结果与实验结果较吻合;轴承的轴心轨迹呈螺旋形;油腔数目对轴心轨迹、气穴和温升的影响很大.

Aimed at the problem that the non-coupling method cannot analyze the interaction of the bearing bush, lubricating oil and journal, and the prohlem that the normal FSI method cannot truly reflect the beating＇s working, a novel transient analysis method combined with the computational fluid dynamics （CFD）, fluid structure interaction （FSI）, and thermal fluid structure interaction （TFSI） was proposed. The multi-physical field coupling of the velocity field, pressure field and temperature field based on timevarying condition were studied, taking cavitations into consideration. Eccentricity, temperature rise, as well as the axial trajectory from the startup to the steady state, were accurately calculated under constant load. The effect of cavities, rotational speed, and load on the pressure, eccentricity, temperature rise, and cavitations was considered. The results obtained by the proprosed method agree well with the experimental results.