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Coupling Effect between Inlet Distortion Vortex and Fan

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Journal of Thermal Science 2023年第3期32卷 1089-1104页

作者： LIU Zepeng huang guoping CHEN Jie YU Zonghan College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In the process of inlet/engine matching,large-scale distortion vortexes would be generated due to lip separation,curved duct,shock-wave boundary layer interaction and other factors of inlet,resulting in complex combination distortion of total pressure and swirl,which would affect the stable and efficient operation of fans/compressors of *** the basis of main distortion vortex characteristics of a typical S-shape inlet and its theoretical model of velocity and pressure distribution,this paper establishes an inlet boundary condition definition method to generate three-dimensional distortion vortex,and presents a study of coupling effect between steady distortion vortex and NASA Rotor *** results show that the fan’s performance curve would move to smaller mass flow direction under the influence of the co-rotating distortion vortex,while fan’s operation curve would change to the opposite direction if the inlet distortion vortex direction is opposite to the fan’s rotating *** with co-rotating distortion vortex,the efficiency loss caused by counter-rotating distortion vortex would be larger and total pressure ratio loss would be *** vortex core size has significant influence on the stability margin of the fan,but has little influence on the efficiency and total pressure ratio *** the vortex core size increases,the range of fan’s tip region with high attack angle would become larger and cause the fan to stall in *** to the non-uniform suction of the downstream fan,the inlet distortion vortex accelerates to mix with the surrounding main *** total pressure distortion decreases and swirl distortion increases along sections from inlet boundary to the fan leading edge.

关键词： inlet/engine compatibility distortion flow fan stall margin flow separation

Investigations of entrainment characteristics and shear-layer vortices evolution in an axisymmetric rear variable area bypass injector

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Chinese Journal of Aeronautics 2022年第4期35卷 230-244页

作者： guoping huang Chao LI Chen XIA Qian LI College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In this study,firstly,for the axisymmetric RVABI,the change-rule of adverse pressure gradient caused by radial velocity during the transition of internal flow mode in variable geometry is summarized,and a Bypass Ratio(BR) iterative algorithm based on the empirical correlation of non-equilibrium pressure is *** algorithm can estimate the nonlinear relationship between area ratio and BR,with an error range falling below 6.5%.Then,we discuss the favorable effect of uniform mixing on the thrust augmentation of mixed exhaust under variable BR *** this point of view,the characteristics of vortices evolution in different shear strength jets are compared,to clarify the effect of variable cycle parameters on jet *** the results suggest,when ■ is as low as 0.22,the K-H disturbance is of high-frequency wavelet property,and it is difficult to induce large-scale spanwise *** macro migrations of fluid elements in span wise vortices and the diffusion effect caused by edge tearing is weak,which is not conducive to the energy exchange between the two ***,the low ■ jet will also correspondingly weaken the viscous dissipation effect of *** is concluded that the dissipation level is proportional to the 2.31 power of the ■.

关键词： Variable cycle engine Rear variable area bypass injector Bypass ratio adjustment Mixed exhaust Thermal mixing Spanwise vortex

Research on windmill starting characteristics of MTE-D micro turbine engine

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Chinese Journal of Aeronautics 2013年第4期26卷 858-867页

作者： Xia Chen Fu Xin Wan Zhaoyun huang guoping Chen Jie College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics

Micro turbine engine （MTE） is an important kind of propulsion system for miniature unmanned aircraft or missiles, because of its better high-speed performance （than propeller propulsion） and higher propulsion efficiency （obviously than rockets）. Windmill start is a common air-starting mode used in micro turbine engine. The windmill starting characteristics are important to the practical use of micro turbine engine. In this paper, the windmill starting characteristics research for a 12 cm diameter （MTE-D） micro turbine engine is carried out by experiment and numerical simulation. The characteristic of rotor mechanical losses at low-speed condition is stud- ied, and the engine common working line of windmill starting process is obtained. Based on the engine windmill characteristics, the propane ignition characteristics under different inflow conditions are researched, and the envelope of propane ignition and propane flameout is determined. The experimental research of fuel supply and ignition characteristics is completed, and the envelope of fuel supply and ignition is obtained. The windmill stage, propane ignition stage, fuel ignition stage and acceleration process from idling-speed to 80% full speed of MTE-D micro turbine engine is optimized, and the optimization windmill starting parameters are collected. The successful wind-mill starting experiment under this condition with engine speed up to 80% full speed indicates that these starting parameters are reasonable. All the starting parameters of MTE-D micro turbine engine obtained in this work are dimensionless parameters, and the conclusions obtained in this study have some reference to other micro turbine engines with the similar structural form and starting process.

关键词： Flameout boundary Ignition characteristics Low speed characteristics Micro turbine engine Windmill starting

Mechanism of adjusting bypass ratio by front variable area bypass injector for a variable cycle engine

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Chinese Journal of Aeronautics 2024年第10期37卷 158-171页

作者： Qian LI Chen XIA guoping huang Omer MUSA Linjun LI Zonghan YU College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China AECC Sichuan Gas Turbine Establishment Chengdu 610500China College of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The Front Variable Area Bypass Injector(FVABI)is a key to bypass ratio adjustment for a Variable Cycle Engine(VCE).In order to study the role of the FVABI with the Core Driven Fan Stage(CDFS)duct,firstly,the engine bypass with the CDFS duct model and the equivalent engine bypass without the CDFS duct model are designed using the concept of a jet boundary *** comparing the difference between airflow driving forces in the two engine bypass models,the quantitative effects of the injection from the CDFS duct on the mass flow rate of the engine bypass airflow are obtained under different combinations of pressure difference and area ***,the CDFS duct injection characteristic map is obtained through the typical experiment of the *** on this map,the performance model of the FVABI is ***,the turbofan engine model with the Variable Inlet Guide Vane(VIGV),the First Variable Cycle Engine model(VCE1)with the CDFS duct and without the VIGV,and the Second Variable Cycle Engine model(VCE2)with the CDFS duct and VIGV are *** gain on the engine bypass ratio adjustment range caused by the injection from the CDFS duct is clarified by comparing the three engine *** is concluded that the bypass ratio adjustment range of the variable cycle engine with the FVABI is about twice that of the traditional turbofan engine.

关键词： Front variable area bypass injector Variable cycle engine Bypass ratio Injection CDFS duct injection characteristic map

Economic Analysis of the International Mobility of Chinese Students Studying Abroad

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China & World Economy 2003年第2期11卷 39-44页

作者： Zhang Guochu huang guoping InstituteofQuantitativeEconomics&TechnologicalEconomics ChineseAcademyofSocialSciences

Since China’s reform and opening up in 1978, the fields in which it engages in foreign exchange and cooperation have broadened and deepened. A prominent feature is the increasing international mobility of Chinese students. Data on international mobility need to be collected and the impacts on China and other countries deserve attention and study.

关键词： of is on In Economic Analysis of the International Mobility of Chinese Students Studying Abroad that for into

IGA nephropathy associated with acute kidney injury in children:the clinicopathological features and risk factors analysis

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IGA nephropathy associated with acute kidney injury in child...

The Influence of Decoction of Ephedra, Baikal skullcap Root, Astragalus Root and Bighead Atractylodes Rhizome to Immunologic Function of Children with RRI

2018年浙江省医学会儿科学分会学术年会

作者： guoping huang The children’s hospital Zhejiang university school of medicine

Objective:There were few related studies about the Clinicopathological features of IGA nephropathy associated with acute kidney injury in *** aim of this work is to find the possible risk factors for ***:We retrospectively analyzed 110 patients between 2.5 and 16 years old with biopsy-proven primary IgAN in the period between 2012 and 2017 in the children’s hospital Zhejiang university school of *** patients were divided into AKI group(n=13) and non-AKI group(n=97).And the definition of acute kidney injury(AKI)referred to 2012 KIDIGO (Kidney Diseases:Improving Global Outcomes) criteria.

关键词：

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cnki会议

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美国中华健康卫生杂志 2005年第4期8卷 81-82页

作者： huang guoping HE Jianfeng CHEN Zhanghai Hospital of Huian County Fujian China

引入DMD方法研究有/无控气流分离的动态结构

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维普期刊数据库

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航空学报 2017年第8期38卷 10-17页

作者：洪树立黄国平南京航空航天大学能源与动力学院南京210016 南京航空航天大学江苏省航空动力系统重点实验室南京210016

为分析非定常流动控制技术抑制分离流的机理,对弯曲扩压通道的试验模型进行了数值模拟,针对扩压通道在无控和采用最佳射流频率状态下的计算结果引入了动力模态分解(DMD)技术进行分析。通过DMD技术能够将包含时空信息的扩压通道复杂流场... 详细信息

为分析非定常流动控制技术抑制分离流的机理,对弯曲扩压通道的试验模型进行了数值模拟,针对扩压通道在无控和采用最佳射流频率状态下的计算结果引入了动力模态分解(DMD)技术进行分析。通过DMD技术能够将包含时空信息的扩压通道复杂流场进行分解,捕获流场包含的动力信息和对应的拟序流动结构。将无控和有控流场分解的结果进行对比分析后表明:采用有效激励措施时,和脱落涡频率一致的涡系对流场的影响更加突显,流场整体上表现得更加有序;非定常控制抑制了一部分涡的增长,使得各模态整体上更加稳定;而有控流场占主导地位的涡系结构相比无控流场较为有序,且对主流区未形成明显的直接影响。

关键词：流动分离非定常流动控制拟序结构动力模态分解(DMD)

Age and severity matched comparison of gender differences in the prevalence of periodic limb movements during sleep in patients with obstructive sleep apnea

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Age and severity matched comparison of gender differences in...