高供气压圆盘止推气体轴承收缩段设计理论研究

摘要

为了实验研究圆盘止推气体轴承气膜间隙中的超音速流动特性,需要保证气膜入口处的气流速度达到临界音速.参考风洞中关于收缩段的设计理论,并结合轴承气膜间隙的流道形状,提出了一种柱对称出流新型双对称收缩段壁面型线的设计方法.利用设计的具有双对称结构的收缩段完成供气孔与气膜间隙的型面过渡,使轴向亚音速来流能够平顺地加速为径向音速气流,并且在气膜入口处该气流具有良好的平稳性和均匀度.数值计算结果验证了理论模型的有效性.%In order to do experimental research on the characteristics of the supersonic flow in the gas film of the circular thrust gas bearing,it should be guaranteed that the velocity of the entrance of gas film reaches the critical sonic.Referring to the design theory of contraction cone of wind tunnels,and the specific shape of bearing clearance,the design method of the curve of wall surface for the new disymmetric contraction cone which has a cylindrosymmetric flow is presented.Using the designed disymmetric contraction cone to complete the transition of inlet orifice and gas film,the axial subsonic flow can be smoothly accelerate to the radial sonic flow,and this flow has good stability and uniformity at the entrance of gas film.The accuracy of the theoretical model is verified by the numerical calculation.