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Chinese Journal of Aeronautics 2021年第8期34卷 16-33页

作者： Yifan YE zhanxue wang Xiaobo ZHANG Shannxi Key Laboratory of Internal Aerodynamic in Aero-Engine School of Power and EnergyNorthwestern Polytechnical UniversityXi'an 710072China

The Efficient Global Optimization(EGO)algorithm has been widely used in the numerical design optimization of engineering ***,the need for an uncertainty estimator limits the selection of a surrogate *** this paper,a Sequential Ensemble Optimization(SEO)algorithm based on the ensemble model is *** the proposed algorithm,there is no limitation on the selection of an individual surrogate ***,the SEO is built based on the EGO by extending the EGO algorithm so that it can be used in combination with the ensemble ***,a new uncertainty estimator for any surrogate model named the General Uncertainty Estimator(GUE)is *** performance of the proposed SEO algorithm is verified by the simulations using ten well-known mathematical functions with varying *** results show that the proposed SEO algorithm performs better than the traditional EGO algorithm in terms of both the final optimization results and the convergence ***,the proposed algorithm is applied to the global optimization control for turbo-fan engine acceleration schedule design.

关键词： Cross-validation Efficient global optimization Engine acceleration schedule design Ensemble of surrogate models Gas turbine engine Optimization methods Surrogate-based optimization

Integration of high-fidelity model of forward variable area bypass injector into zero-dimensional variable cycle engine model

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Chinese Journal of Aeronautics 2021年第8期34卷 1-15页

作者： Fu SONG Li ZHOU zhanxue wang Zhifu LIN Jingwei SHI Shaanxi Key Laboratory of Internal Aerodynamics in Aero-engine School of Power and EnergyNorthwestern Polytechnical UniversityXi'an 710129China

Forward Variable Area Bypass Injector(FVABI)is one of key components which contributes to modulate the cycle parameters of Variable Cycle Engine(VCE)under various operation *** modeling method of zero-dimensional FVABI was reviewed and its deficiency was analyzed based on FVABI flow *** order to improve the accuracy of VCE performance simulation,the high-fidelity modeling method of FVABI was developed based on its working *** it was coupled with the zero-dimensional VCE model and the multi-level VCE model was *** results indicate that the geometric and aerodynamic parameters can affect the interaction between the two airflows and the zero-dimensional FVABI model is too simple to predict the component performance accurately,especially when the FVABI inner bypass is *** on the performance curves for single bypass mode and the regression model of multi-scale support vector regression for double bypass mode,the high-fidelity model can predict FVABI performance accurately and *** integration of high-fidelity FVABI model into zerodimensional VCE model can be done by adjusting iterative variables and balance *** multi-level model has good convergence and it can predict VCE performance when the FVABI inner bypass is chocked.

关键词： Coupling method Forward variable area bypass injector High-fidelity model Multi-scale support vector regression Variable cycle engine

Experimental investigation and numerical analysis on high-efficiency shock vectoring control serpentine nozzles

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CHINESE JOURNAL OF AERONAUTICS 2024年第12期37卷 296-324页

作者： Hui, Zhonghao Shi, Jingwei Lin, Wentao Zhou, Li wang, zhanxue Liu, Yongquan Northwestern Polytech Univ Sch Power & Energy Xian 710072 Peoples R China Natl Key Lab Sci & Technol Adv Light Duty Gas Turb Xian 710129 Peoples R China Collaborat Innovat Ctr Adv Aeroengine Beijing 100191 Peoples R China

The high-efficiency Shock Vectoring Control Serpentine Nozzle (SVCSN) takes into account both thrust vectoring and infrared stealth, and significantly improves the comprehensive performance of the aero-engines through an additional auxiliary duct. In this paper, the schlieren photographs at the exit of the high-efficiency SVCSN and the wall static pressure distributions were obtained by experiments, and the numerical results were used to enrich the thrust vectoring characteristics. The effects of the auxiliary injection were analyzed first to reveal the advantages of the high-efficiency SVCSN compared to the conventional SVCSN. Then, the aerodynamic parameters and the structural parameters of the high-efficiency SVCSN were investigated, including the Nozzle Pressure Ratio (NPR), the Secondary flow Pressure Ratio (SPR), the secondary flow relative area and the secondary flow injection angle. Finally, the coupling performance of the high-efficiency SVCSN is studied by using the approximate modeling technology. Results show that the auxiliary injection increases the range between the two shock legs of the "k" shock wave induced by the secondary flow, then causes the separation zone and high-pressure boss of the down wall to expand upstream, and finally results in a prominent increase in the thrust vectoring performance. The thrust vectoring angle and Vectoring Efficiency (VE) of the high-efficiency SVCSN are about 61.6% and 75.7%, respectively, higher than those of the conventional SVCSN at NPR = 6. The effects of the NPR and the SPR on the thrust vectoring performance of the high-efficiency SVCSN are coupled with each other. A larger NPR matched with a smaller SPR shows better thrust vectoring performance. The maximum fluctuations in thrust vectoring angle and VE caused by the NPR and SPRare about 22% and 64%. The VE decreases monotonously with the increase of the secondary flow relative area. Smaller secondary flow injection angle shows better thrust vector performan

关键词： Shock vectoring control Serpentine nozzle Auxiliary injection Thrust vectoring performance Flow control

ANALYSIS OF DRAWING UNDER LUBRICATION OF NON-NEWTONIAN LUBRICATING MATERIALS

维普期刊数据库评论

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中国有色金属学会会刊：英文版 1995年第4期5卷 173-176页

作者： Lei Zhanbo wang zhanxue Gao Youzhi(Department of Mechanical Engineering,Tsinghua University,Beijing 100084)(Department of Metal Processing, Northeastern University,Shenyang 110006) Tsinghua Univ Beijing China

ＡＮＡＬＹＳＩＳＯＦＤＲＡＷＩＮＧＵＮＤＥＲＬＵＢＲＩＣＡＴＩＯＮＯＦＮＯＮ－ＮＥＷＴＯＮＩＡＮＬＵＢＲＩＣＡＴＩＮＧＭＡＴＥＲＩＡＬＳＬｅｉＺｈａｎｂｏ；ＷａｎｇＺｈａｎｘｕｅ；ＧａｏＹｏｕｚｈｉ（Ｄｅｐａｒｔｍｅ... 详细信息

ＡＮＡＬＹＳＩＳＯＦＤＲＡＷＩＮＧＵＮＤＥＲＬＵＢＲＩＣＡＴＩＯＮＯＦＮＯＮ－ＮＥＷＴＯＮＩＡＮＬＵＢＲＩＣＡＴＩＮＧＭＡＴＥＲＩＡＬＳＬｅｉＺｈａｎｂｏ；ＷａｎｇＺｈａｎｘｕｅ；ＧａｏＹｏｕｚｈｉ（ＤｅｐａｒｔｍｅｎｔｏｆＭｅｃｈａｎｉｃａｌＥｎｇ...

关键词： drawing force rheology upper-bound method non-Newtonian material tribology

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对转开式转子气动设计方法

航空动力学报 2024年第1期39卷 133-144页

作者：王启航周莉王占学西北工业大学动力与能源学院西安710129

提出一种基于升力线理论的对转开式转子(contra-rotating open rotor,CROR)气动设计方法。以推力为设计目标,基于拉格朗日乘子法构建气动设计控制方程组。考虑高飞行马赫数对流动特征的影响,根据激盘模型,采用一道正激波模拟转子的增压... 详细信息

提出一种基于升力线理论的对转开式转子(contra-rotating open rotor,CROR)气动设计方法。以推力为设计目标,基于拉格朗日乘子法构建气动设计控制方程组。考虑高飞行马赫数对流动特征的影响,根据激盘模型,采用一道正激波模拟转子的增压过程。完成速度场预测后,利用压气机三维造型方法完成初始设计。初始设计完成后,对翼型折转角进行修正从而满足目标推力。研究表明,整个设计过程中只需2次计算流体力学(CFD)计算与再设计便可满足目标推力,所需翼型折转角修正量为−0.486°,设计结果的推力与目标推力的相对误差为−0.32%,设计方法高效且具有高的设计精度。

关键词：对转开式转子升力线理论涡格模型拉格朗日乘子法落后角模型

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轴对称矢量喷管气动矢量角和流量系数计算方法研究

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西北工业大学学报 2009年第2期27卷 229-232页

作者：朱燕王占学西北工业大学动力与能源学院陕西西安710072

为定量分析推力矢量对发动机性能的影响,文章基于复杂的三平面几何关联关系建立了轴对称矢量喷管几何矢量角对气动矢量角、流量系数影响的数学模型。通过对比实验结果和用基于CFD方法的数学模型计算的结果,研究了此方法的适用性及它的... 详细信息

为定量分析推力矢量对发动机性能的影响,文章基于复杂的三平面几何关联关系建立了轴对称矢量喷管几何矢量角对气动矢量角、流量系数影响的数学模型。通过对比实验结果和用基于CFD方法的数学模型计算的结果,研究了此方法的适用性及它的实用价值。结果表明此模型适用于大多数喷管,并具有较高的计算精度。

关键词：矢量喷管气动矢量角流量系数

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空天飞机/吸气式推进系统一体化性能的模拟

推进技术 1999年第6期20卷 70-74页

作者：王占学唐狄毅西北工业大学航空动力与热力工程系西安710072

从一体化角度出发，进行了空天飞机／吸气式推进系统一体化性能的数值模拟。给出了涡扇发动机和冲压发动机的参数选择方法和计算结果，采用工程计算的方法，计算了进气道和喷管的特性。

关键词：航天涡轮风扇发动机冲压喷气发动机数值仿真

轮缘封严气流与上游导向器非定常干涉数值研究

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西北工业大学学报 2019年第1期37卷 129-136页

作者：杨帆周莉王占学西北工业大学动力与能源学院陕西西安710072

为了研究涡轮转静盘腔中的轮缘封严气流与主流的非定常干涉效应,在不同封严流量下对上游导向器的流场分布和非定常特性进行了数值模拟。结果表明,封严出流的堵塞作用引起吸力面后半段轮毂附近静压的升高和熵增的减小,以及导向器出口速... 详细信息

为了研究涡轮转静盘腔中的轮缘封严气流与主流的非定常干涉效应,在不同封严流量下对上游导向器的流场分布和非定常特性进行了数值模拟。结果表明,封严出流的堵塞作用引起吸力面后半段轮毂附近静压的升高和熵增的减小,以及导向器出口速度的降低。从无封严腔体到RI=1.7%,5%叶高吸力面静压系数最大增加了6%。封严出流造成横向压力梯度减小使得轮毂通道涡和轮毂尾缘脱落涡的强度减弱。不存在封严气流时,燃气入侵使得10%叶高以下范围非定常波动降低;存在封严气流时,来自燃气入侵和腔体进口的封严出流的耦合作用使得非定常波动不断减弱。

关键词：腔体导向器入侵侵出非定常

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高空台扩压器的数值模拟

推进技术 1998年第6期19卷 66-69页

作者：王占学王建峰唐狄毅西北工业大学航空动力与热力工程系

从雷诺平均的非定常Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程出发，利用时间相关法，采用ＭａｃＣｏｒｍａｃｋ两步显格式，结合Ｂａｌｄｗｉｎ－Ｌｏｍａｘ代数湍流模型，数值模拟了高空台扩压器的内部流场，并计算了扩压器的性能。结果表明，... 详细信息

从雷诺平均的非定常Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程出发，利用时间相关法，采用ＭａｃＣｏｒｍａｃｋ两步显格式，结合Ｂａｌｄｗｉｎ－Ｌｏｍａｘ代数湍流模型，数值模拟了高空台扩压器的内部流场，并计算了扩压器的性能。结果表明，采用求解Ｎ－Ｓ方程的方法计算高空台扩压器性能是一种有效的方法。

关键词：高空仿真试车台扩压器数值仿真航空发动机

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进口导叶形式对核心机驱动风扇级的影响

航空动力学报 2018年第7期33卷 1676-1684页

作者：周莉刘东王占学西北工业大学动力与能源学院陕西省航空发动机内流动力学重点实验室西安710129

以某变循环发动机(VCE)所用核心机驱动风扇级(CDFS)为研究模型,数值模拟了CDFS在真实边界环境下的流动特性,分析了单/双涵道工作模式下,不同形式的可调进口导叶(IGV)对CDFS流动特性及性能的影响机理。结果表明:不同工作模式时,CDFS靠导... 详细信息

以某变循环发动机(VCE)所用核心机驱动风扇级(CDFS)为研究模型,数值模拟了CDFS在真实边界环境下的流动特性,分析了单/双涵道工作模式下,不同形式的可调进口导叶(IGV)对CDFS流动特性及性能的影响机理。结果表明:不同工作模式时,CDFS靠导叶角度的开闭实现大范围的流量调节。单涵道(SB)工作模式时,不同形式的可调进口导叶(VIGV)对CDFS性能的影响差异很小;双涵道(DB)工作模式时采用常规可调导叶(CIGV)会在其吸力面产生较大的流场分离,且流通能力和流量调节范围大大降低。可变弯度导叶通过可转动部分的开闭实现CDFS对流量调节的需求;通过固定部分保证CDFS导叶进口气流攻角基本不变,同时在固定部分和可转动部分连接处所形成的收缩通道的加速效应显著抑制了导叶吸力面的流动分离。可变弯度导叶是适用于CDFS在不同工作模式下性能参数及流量调节需求的可调导叶的形式。

关键词：变循环发动机核心机驱动风扇级工作模式常规可调导叶(CIGV) 可变弯度导叶(VIGV)