【作者】 吴银娥；

【导师】 陈国定；

【作者基本信息】 西北工业大学 ， 机械设计及理论， 2005， 硕士

【摘要】 20世纪80年代后,发展新型密封技术已成为下一代高性能航空发动机研制的“前线部队”。指尖密封技术即是在这一情况下继篦齿密封和刷式密封技术之后发展起来的一种先进密封技术,它对于提高航空发动机性能和寿命具有良好的应用前景,开展指尖密封技术研究是一项迫切的任务,具有重要科学意义。本论文研究的目的就是通过优化设计来选择合理的指尖密封曲梁型线,以获得满足要求的指尖密封结构,从而为进一步的研究奠定基础。 为此,在指尖密封国内外研究现状分析的基础上,本文基于影响指尖密封工作性能和寿命的两个关键因素——迟滞特性和径向刚度特性,着重对指尖密封结构的型线进行了优化选择。 本文首先以迟滞程度最小为目标,根据有关优化理论采用拉格朗日乘子法对指尖曲梁型线进行了优化,并采用有限元技术对优化型线的指尖密封和对数螺线型线指尖密封进行了分析,以比较两者的迟滞性能之间的区别。研究工作表明,较之对数螺线型线本文提出的优化型线指尖密封的迟滞性能获得了很大的改善。在此基础上,针对不同密封位置对迟滞和径向刚度的不同匹配需求,通过对指尖密封曲梁型线优化技术的研究,提出了指尖密封型线主动控制优化设计的方法。其后的优化设计实例及其有限元仿真分析证明了所提出的指尖密封型线主动控制优化方法的可行性和有效性。最后,针对指尖密封型线主动控制优化问题中在要求迟滞比较小的情况下目标函数病态化的现象,提出了相应的处理方法,实现了小迟滞比状态下指尖密封型线的主动控制优化设计,使本文提出的指尖密封型线主动控制优化设计方法具有较大适用性。更多还原

【Abstract】 The research of the new-type seal technology has been the frontier of the development in the next generation aero-engine with high performance after 1980’s~[1]. The finger seal is a new innovative seal after labyrinth seal and brush seal. The purpose of this project is to get the appropriate shape-curve of finger seal for the special work-conditions’ seal demand and establish the base for farther research.With summarized a great deal of datum in home and overseas, based on the finger seal’s hysteresis and stiffness, the paper will discuss the optimized selection of shape-curve in finger seals.Firstly the shape-curve of finger seal is optimized aiming at farthest lowering hysteresis effect with optimization theory. Base on results, the hysteresis effect of finger seal with optimized shape-curve is analyzed with FEM (Finite Element Method), and is compared with hysteresis effect of finger seal with logarithen spiral I shape-curve. The research indicates that compared with finger seal with logarithen spiral I shape-curve, the finger seal with optimized shape-curve is put forward for improvements of hysteresis effect. Furthermore, considering the purpose of reasonable finger seal construction, we present the active control optimization method across the shape-curve optimization design research. The results obtained by FEM show that active control optimization method is reasonable. Finally, according to the morbidity of design objective lead to difficult to get the finger shape-curve of lower hysteresis with the active control optimization method, we bring forward the corresponding design method to achieve the active control optimization of finger shape-curve of lower hysteresis. This make the shape-curve optimization design method by active control in finger seals have more uses.更多还原