【作者】 赵勇；

【导师】 胡骏；

【作者基本信息】 南京航空航天大学 ， 航空宇航推进理论与工程， 2008， 博士

【摘要】 航空燃气涡轮发动机在近半个多世纪的发展中,技术水平取得了空前的进步。风扇/压气机作为航空发动机的关键部件,性能指标随之不断提高,从而对风扇/压气机气动设计体系中的计算方法提出了更高的要求。风扇/压气机非设计点性能计算以及进气畸变影响的预测方法是风扇/压气机气动设计体系中的重要工具,也是业内人士一直以来研究的热点之一。本文开篇回顾了世界各国航空发动机发展历程及一些预研计划的内容,然后在总结风扇/压气机非设计点性能计算和进气畸变影响预测方法发展现状的基础上,详细阐述了本文的主要研究内容和取得的主要研究成果。本文主要开展了以下四个方面的研究工作:一、在系统论述传统的非设计点性能计算方法—基元叶栅法的基础上,发展了适合现代先进多级轴流风扇/压气机气动特点的非设计点性能和稳定边界的计算方法,并通过多台风扇/压气机性能和稳定边界的计算与试验结果的比较,验证了方法的有效性和广泛适用性。二、在均匀进气条件下风扇/压气机非设计点性能计算的基础上,发展了用于分析进气畸变对风扇/压气机性能和稳定性影响的准三维模型,构成了相对完整的多级轴流风扇/压气机非设计点性能和稳定性预测以及进气畸变影响的分析系统。已有算例的结果表明,准三维计算方法灵活、可靠,可应用于工程问题的分析研究,有着较强的工程适用性。三、借鉴三维彻体力模型思想和构成,发展了进气畸变对风扇/压气机性能和稳定性影响的三维非定常计算方法。本计算方法通过非定常激盘,将三维非定常Euler方程和基元叶栅法组成了完整的预测进气畸变对多级轴流风扇/压气机非设计点性能和稳定性影响的三维非定常分析系统。进气畸变条件下的三维计算结果与高、低速风扇/压气机试验结果的比较表明,计算方法快捷、有效,能够反映出进气畸变影响的三维效应,具有重要的学术研究价值和广阔的工程应用前景。四、利用南京航空航天大学低速双级轴流压气机试验器,针对安装畸变网的试验压气机,开展了较为详细的进气畸变试验研究,并详细分析了压气机进口AIP截面总压畸变特性,及其对压气机非设计点性能和稳定性以及压气机失速起始特性的影响。此外,试验验证了在AIP截面采用6支×6点测量方法确定总压畸变特性时,需要根据插值方法加以修正,并给出了针对畸变网的总压畸变特性的修正曲线。本文的主要创新点有:(1)发展了预测现代先进多级轴流风扇/压气机非设计点性能和稳定边界的计算方法,并通过雷诺数关系式的引入,使原有的计算方法具备了评估雷诺数对风扇/压气机性能和稳定性影响的能力。(2)在均匀进气条件下风扇/压气机非设计点性能计算的基础上,发展了计算进气畸变对风扇/压气机性能和稳定性影响的准三维模型,构成了一个相对完整的多级轴流风扇/压气机非设计点性能和稳定性预测及进气畸变影响的分析系统。(3)发展了进气畸变对风扇/压气机性能和稳定性影响的三维非定常计算方法,组成了一个完整的多级轴流风扇/压气机非设计点性能和稳定边界预测及进气畸变影响的三维非定常分析系统。(4)通过临界畸变角概念的引入,有效地将Koch最大静压升系数法应用于进气畸变条件下风扇/压气机稳定边界的预测。在均匀进气和畸变进气条件下,已有算例均验证了该方法的有效性和预测精度。(5)发展的均匀进气条件下风扇/压气机非设计点性能计算方法、进气畸变对风扇/压气机性能和稳定性影响的准三维计算方法,以及进气畸变对风扇/压气机性能和稳定性影响的三维非定常计算方法,构成了多级轴流风扇/压气机非设计点性能和稳定边界预测及进气畸变影响的子系统,可纳入风扇/压气机气动设计体系中,成为分析风扇/压气机非设计点性能和稳定性以及进气畸变影响的系统工具,在现代先进风扇/压气机的设计中起到重要的作用。更多还原

【Abstract】 During the past decades, great progress of engineering techniques has been made for the gas turbine engines. The fan/compressor is a key component of aero-engines, thus its performance parameters are being improved continually, and also design methods. Among techniques, methods for off-design performance computation and for predicting and analyzing influences of the inlet flow distortion as hotspots for researchers are important tools in the fan/compressor aerodynamic design.At the beginning, this thesis reviews the development of aero-engines and the contents of several advanced research plans of the western countries. Based on analysis of the fan/compressor off-design performance computation and some predicting methods of the inlet flow distortion, the main research contents and achievements are expatiated in detail.The main research works are itemized below:Firstly, on the basis of the classical off-design performance computing method, element cascade method, according to aerodynamic characteristic of the modern advanced fan/compressor, a computing method of off-design performance and surge boundary of the multi-stage axial fan/compressor is established, and validated by related experimental data.Secondly, based on the above computation for the uniform inlet flow, a quasi-3D computational model and an integrated analytic system for analyzing the influences on the performance and stability of the fan/compressor in the condition of the distorted inlet flow are built up. The existing results testify that they are flexible, reliable and adaptable, could be used to resolve the engineering problems.Thirdly, enlightened by the theory and composition of the body force model, a 3D unsteady computational method is developed for predicting the influences on the fan/compressor performance and stability when the non-uniform inlet flow. Based on unsteady Euler equations, element cascade method and unsteady actuator method, a 3D unsteady integrated analytic system is set up for the multi-stage axial fan/compressor. Compared with the test results of a high speed and low speed fan/compressor, it is proved that the method is solved quickly and effectively, and can reflect the 3D effect of the inlet flow distortion. Thus the method has the important theoretical value and engineering application foreground. Fourthly, the experimental tests have been carried out in the low speed two-stage axial compressor in test rig with an inlet flow distortion screen in NUAA. The distorted total pressure characteristics and its effects on off-design performance, stability and the stall inception of the test compressor have been investigated emphatically. In addition, it is validated by test results that the distorted total pressure characteristics with the inlet flow distortion screen, measured at AIP by the 6×6 measurement method, have to be corrected for a given correcting method. Finally, some correction curves are given.The main highlights of the thesis consist of the following items:(1) The computing method of the off-design performance and surge boundary for the modern advanced multi-stage axial fan/compressor is developed. By introducing the Reynolds number relation, it can evaluate its influence on the fan/compressor performance and stability.(2) On the basis of the off-design performance computation for the uniform inlet flow, the quasi-3D computational model and the analytic system for analyzing the influences of the inlet flow distortion on the multi-stage fan/compressor performance and stability are built up.(3) The 3D unsteady computing method and the 3D analytic system for computing the multi-stage axial fan/compressor off-design performance, surge boundary and predicting the influence of inlet flow distortion are established.(4) By means of introducing the concept of the critical distortion angle, the Koch’s maximum pressure rise potential is used for confirming the surge boundary effectively and validated by the existing data on the different inlet flow condition.(5) The subsystem for calculating the multi-stage axial fan/compressor off-design performance, surge boundary and predicting the influences of the inlet flow distortion consists of the computing method of the off-design performance and surge boundary for the uniform inlet flow, the quasi-3D and the 3D computational method for analyzing the influences of the inlet flow distortion, and can be brought into the fan/compressor aerodynamic design system and developed as an important design tool.更多还原