【作者】 李俊；

【导师】 刘波；

【作者基本信息】 西北工业大学 ， 航空宇航科学与技术， 2017， 博士

【摘要】 设计高负荷、高效率及宽稳定裕度的压气机是未来航空发动机压气机研究的重要方向,而压气机负荷的提高势必会增加压气机的气动设计难度,优化设计方法的引入可以有效提升高负荷压气机的设计效率,改善压气机的气动性能。本文对优化设计方法在高负荷压气机气动设计中的应用进行了较深入地研究,并且对优化设计方法在高负荷压气机各环节优化得到的最优设计方案的作用机理进行了深入研究,旨在为未来高负荷压气机气动设计搭建一套较完整、高效的优化设计平台,并且通过与优化设计方法的结合探索高负荷压气机气动设计的极限,为未来高负荷压气机气动设计提供技术储备。首先,对优化设计方法进行了深入地研究。本文在对标准人工蜂群算法深入研究的基础上,提出了一种全新的改进人工蜂群算法,并且将提出的新优化算法在低维度条件下、高维度条件下和结合CFD程序条件下的优化性能与遗传算法、粒子群算法、差分进化算法、标准人工蜂群算法和快速人工蜂群算法进行了全方位的对比分析,研究发现全新改进人工蜂群算法(DQABC)在保证解的精度具有较高稳定性的基础上,收敛速度方面较其他优化算法具有较为明显的优势,特别是在高维度、复杂流动等高优化难度的条件下,收敛速度的优势尤为显著。其次,应用研究得到的新优化算法,研究了一种大弯度二维叶型优化设计方法,并进行了试验验证。该优化设计方法将数值计算与叶栅试验结果相结合,可以设计出具有较优气动性能的大弯度叶型,并且在该优化设计的基础上开展了多工况条件下的大弯度叶型优化设计研究,同时对具有较宽工作范围的大弯度叶型的气动特性进行了研究。研究发现叶型前缘形状和负荷分布对大弯度叶型全攻角范围内的气动性能起到至关重要的作用。叶型前缘形状会影响附面层转捩位置及叶型前部附面层厚度的累积,而将大弯度叶型负荷适当后移的气动布局对正攻角条件下气动性能提升具有积极作用,但会对设计点性能产生一定影响。再次,研发了考虑端壁效应的高负荷叶栅优化设计方法,该优化设计方法涵盖了弯曲叶栅、端弯叶栅和前缘边条叶栅三种传统近端壁叶型造型方法,并提出了弯曲联合前缘边条叶栅和端弯联合前缘边条叶栅两种全新的端壁造型方法,对比分析了几种造型方法对流动的影响规律。其中最优弯曲联合前缘边条叶栅具有最优的气动性能,而最优弯曲叶栅具有最差的气动性能,但其气动性能也要远优于直列叶栅。优化后叶栅端壁附面层低能流体径向迁移的高度和径向迁移漩涡尺度会对其气动性能产生较大影响,其中最优弯曲联合前缘边条叶栅在两方面较其他叶栅均有一定优势。然后,对核心机驱动风扇级(CDFS)全三维优化设计方法进行了系统的研究,提出了CDFS全新的气动设计思路,该优化设计方法在设计的每个环节均将两种工作模态下的性能进行耦合考虑,并进行了全三维级环境下多工况复合弯掠的优化设计。设计得到的轴向出气、静子不可调的CDFS在单外涵模态下效率达到88.36%,稳定裕度可以达到18.5%,双外涵模态下效率达到86.66%,稳定裕度可以达到15.1%,并且对CDFS失速机理以及复合弯掠对其气动性能的影响进行了细致的研究。研究发现设计工况下CDFS转子性能主要取决于两种工作模态下进口相对气流角的匹配性,特别是转子尖部的匹配性。在单外涵工作模态下,转子叶尖泄漏涡与激波共同作用导致转子内部流动失稳,而双外涵工作模态下静子根部大尺度泄漏涡,引发静子根部气流阻塞。CDFS转子采用根部后掠尖部前掠并结合正弯的气动布局可以有效减小转子叶尖泄漏涡及二次泄漏对风扇气动性能的影响,提升风扇单外涵工作模态下近失速点的气动性能。而静子采用根部后掠尖部前掠并结合根部正弯尖部反弯的气动布局,可以有效抑制泄漏涡的形成,提升风扇双外涵工作模态下的稳定裕度。最后对吸附式叶型的优化设计进行了全面、细致、深入地研究,完成了对大弯度吸附式叶型的设计,并通过叶栅试验验证优化设计结果。成功设计完成了目前国外公开文献可查扩散因子最高达到0.72的高亚音吸附式叶型,并且突破气动设计极限,利用多缝抽吸技术设计研究了一套弯度达到75°,扩散因子超过0.8的超高负荷吸附式叶型,在对该叶栅进行风洞试验过程中首次使用间断抽吸缝以提高吸附式叶栅强度。并且开展了针对低雷诺数条件下吸附式叶型的优化设计研究,总结了一系列低雷诺数条件下吸附式叶型特征,同时发现了超音吸附式叶型,激波、附面层与抽吸方案之间干涉的特殊现象。更多还原

【Abstract】 Design a compressor with highly load,highly efficiency,and wide stability margin is an important direction for the future aeroengine compressor study.However,the increase of the compressor load will improve the compressor design difficulty.The introduction of the optimized design method can greatly improve the design efficiency of the high-load compressor and improve the aerodynamic performance of the compressor.In this paper,Application research of optimization design method in highly loaded compressor has a deeply research,and the action mechanism of optimal design scheme in each link of the highly loaded compressor design has a deeply research.The aim of this paper is to establish a complete and efficient optimization design system for the future aerodynamic design of high-load compressor,to explore the limit of aerodynamic design of high-load compressor through the combination of optimization design method,and provide technical reserves for future high-load compressor aerodynamic design.Firstly,optimization design method is researched deeply.Based on the study on the standard artificial bee colony algorithm,a new improved artificial bee colony algorithm is proposed,and comparative analysis of the new improved artificial bee colony algorithm with genetic algorithm,particle swarm algorithm,differential evolution algorithm,standard artificial bee colony algorithm and quick artificial bee colony is made in the condition of low-dimension,high-dimension,and combined with CFD program.The new improved artificial bee colony(DQABC)has more advantages than other optimization algorithms based on ensuring high accuracy of solution,especially in the condition of high-dimension and complex-flow,and the convergence rate is superior to other optimization algorithms especially.Secondly,a new optimization method of two-dimensional high turning angle airfoil is proposed by using the new optimization algorithm.This optimization design method combines the numerical simulation with the cascade wind tunnel experiment resulting to design the high turning angle airfoil with high aerodynamic performance.On the basis of this optimization design method,a new optimization design method of high turning angle airfoil with wide operating range is developed,and the aerodynamic characteristics of the high turning angle airfoil with wide operating range are researched.The research finds the shape of the leading edge and the distribution of the load have an important influence on the aerodynamic performance of high turning angle airfoil with wide operating range.The shape of the airfoil leading edge can affect transitional position of the boundary layer and the accumulation of the boundary layer in the front of the airfoil.The aerodynamic configuration of moving load backword appropriately for high turning angle airfoil will achieve a great promotion on the aerodynamic performance of the large positive incidence angle,but will a little negative effect on the performance of design point.Thirdly,an optimazation design method of the high load cascade considering the endwall effect is developed.This optimization design method includes three kinds of traditional endwall modeling methods: bowed cascade,endbend cascade,and leading edge strake cascade.Two kinds of new endwall modeling methods which are bowed cascade combined with leading edge strake cascade and endbend cascade combined with leading edge strake cascade are proposed,and the flow influence of these endwall modeling methods is analyzed.The optimal bowed cascade combined with leading edge strake cascade has the excellent aerodynamic performance,and the optimal bowed cascade has the poorest aerodynamic performance,while its aerodynamic performance is far superior to the straight cascade cascade.The height of the low energy fluid radial migration and the scale of the vortex radial migration have a great effect on the aerodynamic performance.The optimal bowed cascade combined with leading edge strake cascade is superior to the other cascades in both aspects.Fourthly,three-dimensional CDFS optimization design method is developed,and the new aerodynamic design method of CDFS is proposed.In this optimization design method,the aerodynamic performance of two modes is coupling considered,and multi-working conditions composite optimization of lean and sweep under the stage environment is studied.The designed CDFS which contains outlet axial outgassing and unadjustable stator can reach the efficiency of 88.36% and stability margin of 18.5% in the single bypass mode and the efficiency of 86.66% and stability margin of 15.1% in the double bypass mode,and the CDFS stall mechanism and aerodynamic performance influence of the composite optimization of lean and sweep are studied.In the design point the performance of the CDFS rotor depends on the matching of the relative airflow angle under two modes,especially the matching of the rotor tip.In the single bypass mode the interaction of the rotor tip leakage vortex and the shock wave cause the flow instability,and in the double bypass mode large scale leakage vortex of the stator hub can cause the airflow obstruction of the stator.The aerodynamic configuration of backword sweep in the rotor hub and forword sweep in the rotor tip combined with positive bow can reduce the influence of vortex leakage and secondary leakage,and effectively improve the aerodynamic performance of the near-stall point in the single bypass mode,and The aerodynamic configuration of backword sweep in the stator hub and forword sweep in the stator tip combined with positive bow in the stator hub and negative bow in the stator tip can restrain the formation of the leakage vortex and effectively improve the stability margin of the fan in the double bypass mode.Finally,the optimization design method of the aspirated airfoil is studied comprehensively,in details,and deeply.The design of high turning angle aspirated airfoil is completed,and the optimization design result is verified by the cascade wind tunnel experiment.High subsonic aspirated airfoil with the diffusion factor of 0.72 which is the airfoil has the peak load is designed successfully.To explore the limit of aerodynamic design of high-load compressor,anultra highly loaded multi-slot aspirated airfoil with the turning angle of 75° and the diffusion factor of 0.8 is designed,and in the process of cascade wind tunnel experiment,the intermediate slot is used firstly to improve the strength of the aspirated airfoil.The aspirated airfoil optimization design method in the condition of low-Reynolds number is studied,and aerodynamic characteristic of the aspirated airfoil in the condition of low-Reynolds number is summarized simultaneous.The special phenomenon with the interaction of shock wave,boundary layer and aspiration in the supersonic aspirated airfoil is studied.更多还原