为提高航空发动机内、外涵分流环在多工况条件下的环境适应能力,基于Isight优化设计平台,对某缩比双涵风扇-增压级试验件的分流环模型进行气动优化设计研究。采用贝塞尔曲线参数化方法,设置多工况条件对分流环模型进行气动计算,通过拉...为提高航空发动机内、外涵分流环在多工况条件下的环境适应能力,基于Isight优化设计平台,对某缩比双涵风扇-增压级试验件的分流环模型进行气动优化设计研究。采用贝塞尔曲线参数化方法,设置多工况条件对分流环模型进行气动计算,通过拉丁超立方采样生成样本点,进行试验设计(design of experiment,DoE)分析,筛选关键变量;基于自适应模拟退火算法对关键变量自动寻优,获得综合流动损失最小的分流环优化模型,分析3种分流环型线的内外涵道在设计工况下的静压和气流速度分布。仿真结果表明:控制分流环上壁面厚度的3个设计变量对优化结果起主导作用,优化曲线呈现下凹的扁平化趋势,曲线前缘与后端曲率增大,分流环攻角减小,能够有效抑制气流分离、减小流动损失。通过贝塞尔曲线参数化与多工况优化设计,可显著改善分流环的气动性能,提高其在多工况下的适应能力。展开更多
Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages ha...Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages have difficulties in predicting comprehensively Reynolds number effects on airfoils,matching and characteristics curves.This study proposes Re-correction models for loss,deviation angle and endwall blockage based on classical theories and cascade tests,and loss and deviation models show good agreement in test data of NACA65 and C4 cascades.Throughflow method considering Reynolds number effects is developed by integrating the correction models into a verified Streamline Curvature(SLC)tool.A three-stage axial compressor is investigated through SLC and CFD methods from design Reynolds number(Red=2106)to low Re=4104,and the numerical methods are validated with test data of characteristic curves and spanwise distributions at Red.With Re reduction,SLC method with correction models well predicts variation in overall performances compared with CFD calculations and Wassell's model.Streamwise and spanwise matching such as total pressure and loss distributions in SLC predictions are basically consistent with those in CFD results at near-stall points under design and low Reynolds numbers.SLC and CFD methods share similar detections of stall risks in the third stage(Stg3),and their analyses of diffusion processes deviate to some extent due to different predictions in separated endwall flow.The correction models can be adopted to consider Reynolds number effects in through-flow design and analysis of axial compressors.展开更多
This paper introduces a computationally efficient global sensitivity analysis method for quantifying the influence of uncertain clamp support conditions on the natural frequencies of aero-engine pipe systems.The dynam...This paper introduces a computationally efficient global sensitivity analysis method for quantifying the influence of uncertain clamp support conditions on the natural frequencies of aero-engine pipe systems.The dynamic model is based on a three-dimensional Timoshenko beam finite element formulation,with clamps represented as distributed spring elements possessing anisotropic stiffness.To overcome the prohibitive cost of traditional Monte Carlo simulation,the multiplicative dimensional reduction method(M-DRM)is integrated with variance decomposition theory.This approach approximates the high-dimensional frequency response function as a product of univariate components,enabling rapid computation of Sobol’sensitivity indices with a computational cost reduced by three orders of magnitude.Numerical case studies on a planar Z-shaped pipe and a spatial series-parallel configuration reveal that clamp position parameters dominate the system’s natural frequency characteristics.For critical clamps,Sobol’indices exceed 0.8 across multiple vibration modes,whereas stiffness parameters exhibit negligible influence.The proposed methodology provides a rigorous and efficient tool for identifying dominant uncertainty sources,guiding tolerance allocation in manufacturing,and informing robust support design for vibration-sensitive piping systems.展开更多
辅助动力装置(auxiliary power unit,APU)的功能主要是在地面和空中起动发动机,为客舱供气并为机载设备提供电源。为实现辅助动力装置的功能,开展APU控制系统与飞机其他系统的交联设计。首先从飞机级功能开展研究分析,通过APU系统功能...辅助动力装置(auxiliary power unit,APU)的功能主要是在地面和空中起动发动机,为客舱供气并为机载设备提供电源。为实现辅助动力装置的功能,开展APU控制系统与飞机其他系统的交联设计。首先从飞机级功能开展研究分析,通过APU系统功能定义和分析,得到APU系统级功能;再根据APU系统级功能,分析得到APU系统需要与飞机交联的系统,主要是飞机的导航系统、燃油系统、环控系统和动力装置系统等;最后分析确定APU系统与飞机级系统交联的信号,包括APU系统从飞机系统接收的信号,以及各飞机系统从APU系统接收的信号,最终确定APU系统与飞机系统之间相互交联的信号。通过搭载半物理试验方案,实现APU系统与飞机系统交联试验,验证APU系统与飞机系统信号的正确性和完整性。展开更多
文摘为提高航空发动机内、外涵分流环在多工况条件下的环境适应能力,基于Isight优化设计平台,对某缩比双涵风扇-增压级试验件的分流环模型进行气动优化设计研究。采用贝塞尔曲线参数化方法,设置多工况条件对分流环模型进行气动计算,通过拉丁超立方采样生成样本点,进行试验设计(design of experiment,DoE)分析,筛选关键变量;基于自适应模拟退火算法对关键变量自动寻优,获得综合流动损失最小的分流环优化模型,分析3种分流环型线的内外涵道在设计工况下的静压和气流速度分布。仿真结果表明:控制分流环上壁面厚度的3个设计变量对优化结果起主导作用,优化曲线呈现下凹的扁平化趋势,曲线前缘与后端曲率增大,分流环攻角减小,能够有效抑制气流分离、减小流动损失。通过贝塞尔曲线参数化与多工况优化设计,可显著改善分流环的气动性能,提高其在多工况下的适应能力。
基金supported by the National Science and Tech-nology Major Project of China(Nos.2017-II-0007-0021 and J2019-II-0017-0038)。
文摘Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages have difficulties in predicting comprehensively Reynolds number effects on airfoils,matching and characteristics curves.This study proposes Re-correction models for loss,deviation angle and endwall blockage based on classical theories and cascade tests,and loss and deviation models show good agreement in test data of NACA65 and C4 cascades.Throughflow method considering Reynolds number effects is developed by integrating the correction models into a verified Streamline Curvature(SLC)tool.A three-stage axial compressor is investigated through SLC and CFD methods from design Reynolds number(Red=2106)to low Re=4104,and the numerical methods are validated with test data of characteristic curves and spanwise distributions at Red.With Re reduction,SLC method with correction models well predicts variation in overall performances compared with CFD calculations and Wassell's model.Streamwise and spanwise matching such as total pressure and loss distributions in SLC predictions are basically consistent with those in CFD results at near-stall points under design and low Reynolds numbers.SLC and CFD methods share similar detections of stall risks in the third stage(Stg3),and their analyses of diffusion processes deviate to some extent due to different predictions in separated endwall flow.The correction models can be adopted to consider Reynolds number effects in through-flow design and analysis of axial compressors.
基金funded by the Major Projects of Aero-Engines and Gas Turbines grant number J2019-I-0008-0008.
文摘This paper introduces a computationally efficient global sensitivity analysis method for quantifying the influence of uncertain clamp support conditions on the natural frequencies of aero-engine pipe systems.The dynamic model is based on a three-dimensional Timoshenko beam finite element formulation,with clamps represented as distributed spring elements possessing anisotropic stiffness.To overcome the prohibitive cost of traditional Monte Carlo simulation,the multiplicative dimensional reduction method(M-DRM)is integrated with variance decomposition theory.This approach approximates the high-dimensional frequency response function as a product of univariate components,enabling rapid computation of Sobol’sensitivity indices with a computational cost reduced by three orders of magnitude.Numerical case studies on a planar Z-shaped pipe and a spatial series-parallel configuration reveal that clamp position parameters dominate the system’s natural frequency characteristics.For critical clamps,Sobol’indices exceed 0.8 across multiple vibration modes,whereas stiffness parameters exhibit negligible influence.The proposed methodology provides a rigorous and efficient tool for identifying dominant uncertainty sources,guiding tolerance allocation in manufacturing,and informing robust support design for vibration-sensitive piping systems.
文摘辅助动力装置(auxiliary power unit,APU)的功能主要是在地面和空中起动发动机,为客舱供气并为机载设备提供电源。为实现辅助动力装置的功能,开展APU控制系统与飞机其他系统的交联设计。首先从飞机级功能开展研究分析,通过APU系统功能定义和分析,得到APU系统级功能;再根据APU系统级功能,分析得到APU系统需要与飞机交联的系统,主要是飞机的导航系统、燃油系统、环控系统和动力装置系统等;最后分析确定APU系统与飞机级系统交联的信号,包括APU系统从飞机系统接收的信号,以及各飞机系统从APU系统接收的信号,最终确定APU系统与飞机系统之间相互交联的信号。通过搭载半物理试验方案,实现APU系统与飞机系统交联试验,验证APU系统与飞机系统信号的正确性和完整性。
