摘要：In the current state-of-the-art,high-loss flow in the endwall significantly influences compressor ***,the control of endwall corner separation in compressor blade rows is important to *** on the previous research of the Blended Blade and End Wall(BBEW)technique,which can significantly reduce corner separation,in combination with a nonaxisymmetric endwall,the full-BBEW technique is proposed in this study to further reduce the separation in endwall *** principle of the unchanged axial passage area is considered to derive the geometric method for this *** models are further classified based on different geometric characteristics of this technique:the BBEW model,Inclining-Only End Wall(IOEW)model,and full-BBEW *** most effective design of each model is then found by performing several optimizations at the design point and related numerical investigations over the entire operational *** with the prototype,the total pressure loss coefficient decreases by 7%–9%in the optimized full-BBEW at the design ***,the aerodynamic blockage coefficient over the entire operational range decreases more than the other models,which shows its positive effect for *** approach has a larger decrease at negative incidence angles where the intersection of the boundary layer plays an important role in corner *** analysis shows that the blended blade profile enlarges the dihedral angle and creates a span-wise pressure gradient to move low momentum fluid towards the ***,the inclining hub geometry accelerates the accumulated flow in the corner downstream by increasing the pressure ***,though losses in the mainstream grow,especially for large incidences,the full-BBEW technique effectively reduces the separation in corners.

摘要：Adjoint-based optimization method is a hotspot in ***,this paper presents principles of adjoint method from Lagrange multiplier ***,combining a continuous route with thin layer RANS equations,we formulate adjoint equations and anti-physical boundary *** to the multi-stage environment in turbomachinery,an adjoint interrow mixing method is *** techniques of solving flow equations and adjoint equations are almost the same,and once they are converged respectively,the gradients of an objective function to design variables can be calculated using complex method ***,integrating a shape perturbation parameterization and a simple steepest descent method,a frame of adjoint-based aerodynamic shape optimization for multi-stage turbomachinery is *** last,an inverse design of an annular cascade is employed to validate the above approach,and adjoint field of an Aachen 1.5 stage turbine demonstrates the conservation and areflexia of the adjoint interrow mixing *** a direct redesign of a 1+1 counter-rotating turbine aiming to increase efficiency and apply constraints to mass flow rate and pressure ratio is taken.

摘要：In the present paper,the design of a transonic centrifugal compressor stage with the inlet relative Mach number about 1.3 and detailed flow field investigation by three-dimensional CFD are *** the CFD program was validated by an experimental *** the preliminary aerodynamic design of stage completed through in-house one-dimensional *** types of impellers and two sets of stages were computed and *** can be found that the swept shape of leading edge has prominent influence on the performance and can enlarge the flow ***,the performance of the stage with swept impeller is better than *** total pressure ratio and adiabatic efficiency of final geometry achieve 7:1 and 80% *** vane diffuser with same airfoils along span increases attack angle at higher span,and the local flow structure and performance is deteriorated.

摘要：The ultra-high bypass ratio turbofan engine attracts more and more attention in modern commercial engine due to advantages of high efficiency and low Specific Fuel Consumption(SFC). One of the characteristics of ultra-high bypass ratio turbofan is the intermediate turbine duct which guides the flow leaving high pressure turbine(HPT) to low pressure turbine(LPT) at a larger diameter, and this kind of design will lead to aggressive intermediate turbine duct(AITD) design concept. Thus, it is important to design the AITD without any severe loss. From the unsteady flow's point of view, in actual operating conditions, the incoming wake generated by HPT is unsteady which will take influence on boundary layer's transition within the ITD and LPT. In this paper, the three-dimensional unsteady aerodynamics of an AITD taken from a real engine is studied. The results of fully unsteady three-dimensional numerical simulations, performed with ANSYS-CFX(RANS simulation with transitional model), are critically evaluated against experimental data. After validation of the numerical model, the physical mechanisms inside the flow channel are analyzed, with an aim to quantify the sensitivities of different Reynolds number effect on both the ITD and LPT nozzle. Some general physical mechanisms can be recognized in the unsteady environment. It is recognized that wake characteristics plays a crucial role on the loss within both the ITD and LPT nozzle section, determining both time-averaged and time-resolved characteristics of the flow field. Meanwhile, particular attention needs to be paid to the unsteady effect on the boundary layer of LPT nozzle's suction side surface.

摘要：A model equations, Time-Averaged N-S equations which is suitable for simulation of time-averaged flow in multistage turbomachines, is derived. According to engineering requirements, Time-Averaged N-S equations theory is used to simulate time-averaged flow on two levels. The first level is interface treatment technique, at this stage General Continuous Interface method is presented, following this time-average correlation terms are modeled with semi-experimental method put forward by the author, and included into computations. A two-stage fan and A one-stage fan flow-field are computed with these two method respectively. Results show that simulations are more near reality under Time-Averaged flow *** it is very necessary to include Time-Averaged flow simulation into turbomachinery design system, mainly Rotor/Stator interaction time-average effects must be embedded in the Time-Averaged flow simulations.

摘要：横向二次流是制约叶轮机气动负荷进一步提升的主要因素。在叶片通道内施加涡流发生器有抑制通道横向二次流的潜力,但涡流发生器的最优施加方案很难确定。基于涡流发生器经验统计模型(BAYC模型)和响应面方法建立了一种端壁涡流发生器的高效设计方法。基于这一方法,实施于NACA 65直列叶栅,得到了三种涡流发生器优化方案,并在设计工况下和非设计工况下讨论了涡流发生器对端壁横向二次流的控制机理,发现具有更大的涡流发生器高度和更多的涡流发生器数量的方案在面对大攻角下的强横向二次流情况时能够有更强的余力对横向二次流加以控制,大大扩展了叶栅的攻角适用范围。

摘要：为了研究喉部面积比、喉部位置及稠度对超声速叶栅最小损失点性能的影响,基于直接控制通道的造型方法获得一系列设计马赫数为1.4且具有不同通道参数的平面叶栅。数值计算与流场分析结果表明:根据叶栅通道内激波系结构的不同可将其划分为启动态叶栅与过渡态叶栅。喉部参数主要通过改变激波系位置影响叶栅性能。启动态叶栅喉部面积比越小、喉部位置越靠前,其最小损失越小、静压比越高;过渡态叶栅则相反。稠度改变时叶栅通道中激波系结构发生变化,大稠度叶栅大多处于启动态,最小损失小且静压比高;小稠度叶栅大多处于过渡态,具有更大的裕度。

摘要：为了解决通流特性分析程序中原始模型对压气机性能预测精度不足的问题,提高压气机通流特性分析过程的可靠性,基于对大量多圆弧叶栅的数值模拟结果建立了压气机叶栅性能数据库,并以该数据库为依托,采用神经网络建模方法建立了压气机叶栅基准损失系数和基准落后角模型。结果显示:两模型对叶栅基准损失系数和基准落后角的预测精度均满足工程应用要求,其精度分别为±0.002和±1°。在对采用神经网络模型的通流特性分析程序校验过程中发现,其无论对压气机整机性能还是对流动细节的预测精度上都获得了显著提高,尤其是在主流区。此外从压气机整体特性上看,基准损失系数和基准落后角精度的提高对非设计工况损失系数和落后角的预测精度影响是积极的。

摘要：无静叶对转风扇/压气机能有效减小发动机陀螺力矩,在轴向长度方面具有优势。然而,无静叶往往导致下游叶片攻角变化较大,变工况性能难以保证,且这一特点随叶尖切线速度的增大而恶化。本文利用小尺寸涡扇发动机风扇叶片根部周向速度较低的特点,尝试对其进行风扇与压气机无静叶对转方案设计。通过速度三角形分析了无静叶对转风扇/压气机的性能特点,开发了无静叶对转风扇/压气机一维设计程序进行参数方案的筛选优化,设计得到小尺寸无静叶对转风扇/压气机构型方案,设计点效率为85.1%,压比为3.16。结果表明,对转压气机的下排叶片相对进口气流角的变化范围较常规转叶+静叶相对进口气流角范围更小,而对转下排叶片的进口速度却将增大1.5~3倍,因此,需要合理选择对转风扇/压气机的轮毂比及转速比,才能保证对转风扇/压气机变转速工况下的设计点效率及失速裕度。减小对转风扇/压气机转速比有利于提高设计点效率和裕度,但本文受发动机总体指标限制,对转速比选择进行了折中。

摘要：一维特性计算作为压气机设计体系的关键环节,在压气机的初始设计阶段发挥了重要作用。作为一种高度经验化的工程近似计算方法,一维性能计算需要大量实验数据的支撑。从实验数据中总结得到的经验关联式的质量,是决定一维计算成功与否的关键。在充分调研欧美以级叠加方法和平均线方法为主的一维性能分析方法的基础上,回顾了轴流压气机一维特性计算方法的起源,讨论了其发展趋势与研究现状。对一维特性计算方法的基本原理及其所使用的经典经验关联式进行了整理总结,指明了压气机一维性能分析未来进一步发展的方向。