基于流固热耦合的航空发动机刷式密封摩擦与磨损特性研究

项目名称： 基于流固热耦合的航空发动机刷式密封摩擦与磨损特性研究

项目编号： No.51305224

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 机械、仪表工业

项目作者： 李永健

作者单位： 清华大学

项目金额： 26万元

中文摘要： 提高密封性能是提升航空发动机性能的关键基础技术之一。本项目围绕航空发动机高性能刷式密封开展基于流固热耦合的刷式密封摩擦、磨损特性研究，提出通过表面摩擦特性控制改善刷式密封工作性能的技术方案。研究着眼于刷式密封的柔性阵列式刷丝结构与流场的耦合作用机制；通过理论建模和实验观测，探明密封工作过程中结构参数、工况参数对刷丝阵列内的微间隙流动及刷丝力学行为的影响；进而通过接触力学模型和摩擦磨损试验，分析密封过程的摩擦特性和磨损规律；在此基础上，分析摩擦生热对密封结构变形和间隙流动的影响，以及三者的耦合作用规律；确定刷式密封的摩擦、磨损机理和影响因素。重点通过迟滞特性实验，获得摩擦力对刷丝动态行为的影响规律，建立考虑摩擦力的流固热耦合模型，确定改善刷式密封动态性能的表面摩擦特性需求；进而通过表面微结构和物理特性控制技术，得出基于表面控制的刷式密封结构设计理论和方法，提升刷式密封的动态工作性能。

中文关键词： 刷式密封；航空发动机；摩擦；迟滞；多场耦合

英文摘要： The improvement of sealing technology is one of the key ways to enhance the performances of the aeroengine. This project will carry out researches on the friction and wear charateristics of the brush seals based on the Thermal-Hydro-Elastic coupling. A new technical solution which the surface tribological charateristics controlling technology is used to improve the performances of the brush seal is proposed too. The work focus on the coupling mechanism between the flexible array structure of the seal and the micro flow among the bristles. To verify the influences of the sturcture parameters and the operating conditions on the micro flow and the mechanical behavior of the bristles, theoretical modeling and experimental observation are carried out. And then the friction charateristics and wear law are analyzed by the means of contact mechanics and tribological tests. With these results, effect of the heat generation by friction on the deformation of the seal structure and the variation of the micro flow is investigated. The sealing performance affected by the friction and wear is studied. Special stress is laid on the hysteresis test to obtain the influencing rules of the friction on the dynamic behavior of the bristles. A Thermal-Hydro-Elastic coupling modle taking friction into account is built and the demand of

英文关键词： Brush Seal；Aeroengine；Friction；Hysteresis；Multiphysics coupling