【作者】 韩吉昂；

【导师】 钟兢军；

【作者基本信息】 哈尔滨工业大学 ， 动力机械及工程， 2009， 博士

【摘要】 随着现代航空发动机和燃气轮机向高推重比和高功率重量比方向发展,压气机除了要具有优异的气动性能之外,还需要具有良好的结构方案。新颖和好的结构方案不仅能够为压气机气动性能的改进和提高提供有力的支持,还可以使压气机的零部件数量适当减少、结构简单、轴向及外廓尺寸小和重量轻,而具有这样结构优点的压气机能够显著减轻航空发动机和燃气轮机的整体重量,从而有效提高现代航空发动机和燃气轮机的推重比和功率重量比。基于激波压缩技术的旋转冲压压缩转子这种具有新颖结构的压缩系统在设计过程中融合了超声速进气道中所用的激波压缩技术与传统轴流式和离心式压气机的设计技术,与常规压气机相比,具有单级压比高、压缩效率高、产生损失的气动面积小、结构简单、轴向长度短和重量轻的优点。这种新型压缩系统本身所固有的优点使对于飞行状态比较固定且对发动机流量要求不大的航空飞行器和船舶、车载及工业燃气轮机来说有着令人期待的应用前景。因此,对其开展全面、深入的研究就具有重要的理论意义和实用价值。本文首先对旋转冲压压缩转子的总体方案进行了研究,提出了三种轮盘结构形式的中空轴旋转冲压压缩转子结构方案,给出了旋转冲压压缩转子总体结构参数,探讨了旋转冲压压缩转子可能采用的泄漏密封措施和转子支撑结构。根据所确定的旋转冲压压缩转子总体结构参数,特别是旋转冲压压缩转子轮缘进气流道的总体结构参数,设计并数值研究了二元超声速内压式进气道的流场及性能,在研究中重点考虑了喉部与进口高度比、扩压角、背压和来流马赫数对二元超声速内压式进气道的影响情况。随着喉部与进口高度比的增加,进气道的总压恢复系数有先增大后减小的趋势,适当的扩压角有利于进气道总压恢复系数的提高,背压对进气道的性能和出口气流参数分布的均匀性影响较大;来流马赫数的增加会造成进气道总压恢复系数的降低。在二维超声速内压式进气流道设计及数值研究的基础上,借鉴二维超声速进气道设计方法,设计了旋转冲压压缩转子二维进气流道,并重点研究了压缩面形状、喉部长高比、转速和背压对二维进气流道中波系结构、内部流动特点和性能的影响。在本文的研究条件下,凸曲线压缩面二维进气流道综合性能最好,直线压缩面二维进气流道综合性能次之,抛物线压缩面旋二维进气流道综合性能最差。选择综合性能相对较好的凸曲线压缩面二维进气流道设计方案作为蓝本,通过参数化柱面螺线方程和CAD软件设计旋转冲压压缩转子三维进气流几何模型,并采用全三维数值模拟方法对其设计及非设计工况下的流场和性能进行了数值仿真。随着转速的增加,旋转冲压压缩转子三维进气流道的增压比不断提高,而其绝热效率却不断降低;背压增加时旋转冲压压缩转子三维进气流道的增压比逐渐提高,其绝热效率总体上却有先增大后减小的趋势;与常规轴流压气机不同,旋转冲压压缩转子的特性曲线垂直于流量坐标轴;为了提高旋转冲压压缩转子的总体性能,除了需要在增压比和绝热效率之间进行合理的折衷选择外,还要对三维进气流道进行结构优化设计和波系优化配置,这也有利于降低进气流道出口的绝对速度。论文的最后对旋转冲压压缩转子的起动问题和发展前景进行了讨论。更多还原

【Abstract】 With the development of the modern aircraft engines and gas turbine, high thrust-weight ratio and high power-to-weight ratio are the main directions of the research. For compressor, it needs to have good structure, in addition to excellent aerodynamic performance. As new and well designed structure could not only improve and enhance the aerodynamic performance of the compressor, it will also benefit the compressor with appropriately reducing the number of components, simplifying structure, and diminishing the axial and outside profile size, lightening weight. With all of the structure advantages, the compressor could significantly reduce the total weight of aircraft engine and gas turbine, and thus can effectively improve the thrust-weight ratio and power-to-weight ratio of modern aircraft engines and gas turbines.Ram-rotor based on shock compression technology is a new type of compression system with novel structure. Integrating the shock compression technology used in supersonic intake with the traditional axial and centrifugal compressor design technology, this new system has many advantages, such as high pressure ratio in a single-stage, high compression efficiency, small aerodynamic loss surface, simple structure, short axial length and light weight compared with the conventional compressor. With inherent advantages, the new compression system has wide application prospect in aircraft with steady flying conditions and low mass flow rate required in engines, ship power, vehicle engines and industrial gas turbines. So, there is theoretical significance and application value for us to carry out comprehensive and thorough research on the new compression system. The overall design program of the ram-rotor is investigated firstly in this dissertation. Three kinds of hollow shaft ram-rotor with different disk structure are presented and the overall structure parameters are given out. Then the possible seal leakage and support problems are discussed. According to the given overall structure parameters of the ram-rotor, especially the parameters of the flow-path, a 2D internal-compression supersonic intake is designed, and its flow field and performance are investigated numerically. The height ratio of throat and inlet, the divergent angle of the diffuser, back pressure and Mach number of the incoming flow are considered seriously. As the height ratio of throat and inlet increases, the total pressure recovery coefficient increases firstly and then decreases. Appropriate divergent angle can improve the total pressure recovery coefficient. Back pressure has a significant influence on the performance and aerodynamic parameters distribution at outlet. The increasing of the incoming flow Mach number will decrease the total pressure recovery coefficient.On the basis of the design and numerical research on the 2D internal- compression supersonic intake, 2D flow-paths of the ram-rotor are designed according to the design method of the supersonic intake. The influences of compression ramp shape, length-height-ratio of the throat, rotational speed and back pressure on shock structure, flow characteristics and performance are well studied. On the conditions appointed in this dissertation, the flow-path with convex curve compression ramp has the best overall performance, and the performance of the flow-paths with linear compression ramp and parabola compression ramp are secondary and worst respectively.Referring to the 2D flow-path with convex curve compression ramp, a 3D flow-path of the ram-rotor is designed using parametric cylindrical spiral equation and CAD software. Then 3D numerical simulation is adopted to study the flow field and performance of the ram-rotor at design point and off-design points. With the rotational speed increasing, the total pressure ratio of the ram-rotor rises, but the adiabatic efficiency decreases. When back pressure increases, the total pressure ratio rises, the adiabatic efficiency increases firstly, then decreases. Compared with the conventional axial compressor, the performance curves of the ram-rotor are vertical to the axis of mass flow rate. In order to improve the total performance, it needs not only make a compromise between the total pressure ratio and the adiabatic efficiency appropriately, but also optimize the shock structure and the 3D structure of the flow-path, and these will also give benefit to reducing the absolute speed at outlet.At the end of this dissertation, the starting problem and prospect of the ram-rotor are discussed.更多还原