冷气喷射对涡轮平面叶栅气动性能的影响研究

【作者】 凌代军；

【导师】 黄振南； 姜正礼；

【作者基本信息】 电子科技大学 ， 机械工程， 2010， 硕士

【摘要】 航空发动机担负着为飞行器及机载设备提供动力和能源的使命,被誉为飞机的“心脏”,是推动飞机和整个航空工业蓬勃发展的源动力。随着航空技术的发展,飞行器对航空发动机推重比、可靠性、寿命、油耗、全寿命期成本等提出了更高的要求。提高航空发动机涡轮前燃气温度对发动机性能提升具有十分重要的意义,是增大航空发动机推重比的主要方法之一。这将使涡轮的工作环境更为恶劣,保证涡轮在高温环境下稳定、可靠工作的基本措施除采用性能更良好的耐高温材料外,更主要是采用有效的冷却方法。在近几十年来航空发动机的发展中,有效的冷却方法比材料性能的提高对燃气温度提高的贡献大的多。气膜冷却法是航空发动机涡轮冷却中广泛使用的一种有效方法,冷却空气通过涡轮叶片表面的气膜孔排入主流道时与主流的掺混不可避免地对涡轮气动性能带来不利的影响,因此在进行气膜冷却热防护分析的同时还需研究它对涡轮气动性能的影响。实践表明,气冷涡轮叶片中冷气喷射孔位置、角度、冷气流量等对气膜冷却效果、涡轮的气动性能以及整台发动机的推重比都有十分重要的影响。国外经验表明,带冷气喷射的平面叶栅试验是研究气膜冷却的一种经济、快速的手段。利用它可以详细的研究气膜冷却的气动和几何参数对冷却效果、涡轮气动性能的影响。目前国内在冷气喷射对叶型气动性能影响的研究方面以理论计算为主,成系列具有工程应用价值的超跨音速气冷涡轮叶栅试验研究开展还很少,本文就是在上述背景下就针对开展带冷气喷射超跨音速涡轮叶栅试验进行设备改造建设、试验件设计和试验研究,研究冷气喷射流量比对涡轮转子叶栅气动性能的影响,为带气膜冷却涡轮叶片气动设计提供参考,为相关设计体系的建立提供试验依据。更多还原

【Abstract】 Aero engines are called as“the heart of aircraft”, because they provide propulsion and power for flying vehicles and airborne devices. Along with the developing of aeronautic technology, aero engine shall fulfill higher requirements in thrust ratio, reliability, life, fuel consumption and life-time cost. It is one of the main methods which can enhance the thrust ratio of a engine that increasing the turbine entrance temperature (TET). Unfortunately, a higher TET means worse working condition of the turbine. It requires better materials and a better cooling method, or the turbine can not work normally. In history, the contribution of advanced cooling method is more significant than that of the progress of materials.Film cooling is a wildly used method. Cooling air enters the main flow passage and mixes with the gas stream through holes on the surface of turbine blade, and harms the aerodynamic performance of the turbine. Therefore, it is essential that study the influence of air film on the aerodynamic performance of turbine. From experiences, main factors include positions of holes, the injection angle and the mass flow of cooling air.Linear cascade test with cooling air injection is an economic, short-period way to study film cooling. There is rarely a research about super-trans-sonic linear turbine cascade test for studying the influence of film cooling in China, but a great many works in calculation and CFD simulation. This paper tries give some research in this field. Firstly, a super-trans-sonic turbine cascade test is designed and performed. Then, a study on the influence of film cooling is performed by analyzing the result of the test. This paper is going to provide evidence for turbine vane and blade design.更多还原