交变流动下间隙密封耦合气体轴承的特性研究

Research on Characteristics of Clearance Seal Coupled Gas Bearing Under Oscillating Flow

气体轴承是回热式热机的一项关键技术,它是利用气体代替润滑油作为润滑剂,在轴与轴承套之间构成气膜,是避免运动面与静止面直接接触的较为理想支撑元件。将间隙密封与气体轴承相结合,可以在实现密封的同时消除接触磨损。本文利用ANSYS Fluent对具有77 kW(声功)设计输出能力的活塞进行其气体轴承与间隙密封耦合特性的数值模拟与分析,指导该新型气路结构的优化设计,并验证其在大功率自由活塞斯特林发动机中应用的可行性。

The gas bearing is one of the key technology for regenerative engines with pistons.It uses gas film as a lubricant between the piston and the cylinder.Combining the clearance seal with gas bearing technique,one can eliminate contact wear at the mean time sealing cavities with different pressure.In this study,the numerical simulation has been carried out for clearance seal coupled with gas bearing,and the coupling characteristics of these two has been analyzed.A piston designed for a free piston stirling engine has been used as the research object where the piston has the capability of transmitting over 70 kW acoustic power.This work may guide the optimization of the new gas circuit structure design and verify the feasibility of its application in high-power free piston stirling engine.