基于厚板的弹性环式挤压油膜阻尼器建模及动力学特性系数识别

利用数值方法完善了弹性环式挤压油膜阻尼器（elastic ring squeeze film damper,ERSFD）的流固耦合计算模型,其中利用雷诺方程建立油膜的控制方程,利用厚板单元建立了弹性环的运动方程并采用分时迭代方法实现了弹性环-油膜的控制方程的耦合求解从而获得瞬时内外油膜的压力,并进一步识别了油膜以及ERSFD的动力学特性系数。结果表明ERSFD的阻尼系数受凸台高度影响最大,凸台高度从0.15mm增加到0.30mm, ERSFD的阻尼系数从5790(N·s)/m减小到718(N·s)/m; ERSFD刚度系数则主要取决于弹性环的厚度以及凸台数目,弹性环厚度从0.8mm增加到1.0mm,ERSFD的刚度从1.44×106N/m增加到2.51×106N/m。 

Numerical modelling of elastic ring squeeze film damper based on thick plate and force coefficient identification

The two way couple model of elastic ring squeeze film damper(ERSFD) was established through numerical approach. The governing equation of the fluid block was obtained by Reynolds equation and the equation of motion of the elastic ring was solved by finite element method with thick plate. The coupled equations were solved through block iteration method. The transient pressure profile of inner film and outer film were obtained and the force coefficients of ERSFD were identified. The results show that the height of the boss has significant influence on the damping of the ERSFD. The increase of the height of the boss from 0.15mm to 0.30mm results in a drop of damping from 5790(N·s)/m to 718(N·s)/m. The stiffness coefficients of ERSFD have close relations with the thickness of the ring as well as the number of boss. The increase of thickness of elastic ring from 0.8mm to 1.0mm leads to the increase of the stiffness coefficients from 1.44×106N/m to 2.51×106N/m.