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Chinese Journal of Aeronautics 2022年第8期35卷 30-44页

作者： Hao FU Ling ZHOU Lucheng JI School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Institute for Aero Engine Tsinghua UniversityBeijing 100084China

It has been recently shown that Sub Boundary layer Vortex Generator(SBVG,abbreviated as VG hereafter)can suppress the Cross-Flow(CF),and therefore,can eliminate corner separation and increase aerodynamic loading when installed on the end wall inside middle-load compressor passages.However,when VGs are applied in high-load compressors,it is difficult to achieve ideal results.This is because the definition of the VG attack angle in the presence of CF in existing research is confusing,and the stronger CF in high-load compressors worsens the problem and results in an improper design and optimization range of VG attack angle.Therefore,this paper clarifies the definition of the VG attack angle in the presence of CF and reveals the CF controlling mechanism of VG on a flat plate.The differences in the flow phenomena around a VG both with and without CF are also studied.The numerical results show that a larger height or attack angle of the VG generates a greater CF suppression effect.However,the cross velocity increases when surmounting the primary vortex induced by the VG,except that this enhanced CF is less conspicuous for larger VG heights.Compared to the cases without CF,the VG suffers an additional loss because of the stronger separation and primary vortex loss caused by the CF.

关键词： compressors Corner separation Cross-flow Flat plate Vortex generator

Laves phase hydrogen storage alloys for super-high-pressure metal hydride hydrogen compressors

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Rare Metals 2011年第3期30卷 227-231页

作者： GUO Xiumei WANG Shumao LIU Xiaopeng LI Zhinian LU Fang MI Jing HAO Lei JIANG Lijun Energy Material and Technology Institute General Research Institute for Nonferrous Metals Beijing 100088 China

Ti-Cr- and Ti-Mn-based alloys were prepared to be low- and high-pressure stage metals for a double-stage super-high-pressure metal hydride hydrogen compressor. Their crystallographic characteristics and hydrogen storage properties were investigated. The alloy pair Ti0.9Zr0.1Mn1.4-Cr0.35V0.2Fe0.05/TiCr1.55Mn0.2Fe0.2 was optimized based on the comprehensive performance of the studied alloys. The product hydrogen with a pressure of 100 MPa could be produced from 4 MPa feed gas when hot oil was used as a heat reservoir.

关键词： hydrogen storage alloys hydrides Laves phase compressors hydrogen

Trailing-edge shock loss control with self-sustaining synthetic jet in a supersonic compressor cascade

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Chinese Journal of Aeronautics 2023年第7期36卷 366-377页

作者： Yinxin ZHU Wenqiang PENG Zhenbing LUO Qiang LIU Wei XIE Pan CHENG Yan ZHOU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

To effectively reduce the loss of strong shock wave at the trailing edge of the supersonic cascade under high backpressure,a shock wave control method based on self-sustaining synthetic jet was proposed.The self-sustaining synthetic jet was applied on the pressure side of the blade with the blow slot and the bleed slot arranged upstream and downstream of the trailing-edge shock,respectively.The flow control mechanism and effects of parameters were investigated by numerical simulation.The results show that the self-sustaining synthetic jet forms an oblique shock wave in the cascade passage which slows down and pressurizes the airflow,and the expansion wave downstream of the blow slot weakens the shock strength which can effectively change the Mach reflection to regular reflection and thus weaken the shock loss.And the suction effect can reduce loss near blade surface.Compared with the baseline cascade,the self-sustaining jet actuator can reduce flow losses by 6.73%with proper location design and vibration of diaphragm.

关键词： compressors Flow control Mach reflection Trailing-edge shock Self-sustaining synthetic jet Shock waves Supersonic cascades

An intuitive parameterization method with inherently high-order differentiability for compressor blade sections based on ellipse hierarchical deformation

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Chinese Journal of Aeronautics 2023年第8期36卷 74-90页

作者： Chuanrui SI Jinxin CHENG Zhengqing ZHU Zhitong CHEN Qinglong HAO School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Zaozhuang Beihang Machine Tool Innovation Research Institute Co. LtdZaozhuang 277500China Ningbo Institute of Technology Beihang UniversityNingbo 315832China

Shape parameterization has a crucial influence on the optimal solution of aerodynamic optimization.This paper proposes a novel parameterization method for compressor blade sections based on the three-level deformation of the ellipse,which simultaneously satisfies the requirements of flexibility,smoothness,intuitiveness,and compactness.In proposed method,the first-level deformation directly controls nine key geometric parameters to construct the blade section profile,and then the second-and third-level deformations are performed respectively to coarsely and finely modify the profile while keeping the key geometric parameters unchanged.These three levels of deformation effectively decompose the design space without destroying the ellipse’s infinite differentiability,allowing designers to work only with intuitive shape-related parameters to design blade sections with inherently high-order continuity.To verify the effectiveness,six existing blade sections are first fitted and then one of them is selected for a three-level optimization.The results show that the geometry and aerodynamic performance of the fitted and the original blade sections are in good agreement,and the loss coefficient of the optimized blade section is reduced by a total of 36.41%,with 27.34%,8.45%,and 0.62%reductions for the first to the third level,respectively.Therefore,the proposed parameterization method facilitates the design of lower-loss and higher-load compressor blade sections.

关键词： Aerodynamics Blade sections compressors Deformation Ellipse Parameterization

Computer-Aided Solution to the Vibrational Effect of Instabilities in Gas Turbine compressors

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Engineering（科研） 2010年第8期2卷 658-664页

作者： Ezenwa Alfred Ogbonnaya Hyginus Ubabuike Ugwu Charles Agbeju Nimibofa Johnson 不详

Surge and stall are the two main types of instabilities that often occur on the compressor system of gas turbines. The effect of this instability often leads to excessive vibration due to the back pressure imposed to the system by this phenomenon. In this work, fouling was observed as the major cause of the compressor instability. A step to analyze how this phenomenon can be controlled with the continuous examination of the vibration amplitude using a computer approach led to the execution of this work. The forces resulting to vibration in the system is usually external to it. This external force is aerodynamic and the effect was modeled using force damped vibration analysis. A gas turbine plant on industrial duty for electricity generation was used to actualize this research. The data for amplitude of vibration varied between -15 and 15 mm/s while the given mass flow rate and pressure ratio were determined as falling between 6.1 to 6.8 kg/s and 9.3 to 9.6 respectively. A computer program named VICOMS written in C++ programming language was developed. The results show that the machine should not be run beyond 14.0 mm vibration amplitude in order to avoid surge, stall and other flow-induced catastrophic breakdown.

关键词： Computerized Solution Instabilities Vibration Gas Turbine compressors Operational Limits

International conference on compressors and their systems

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Coherent addition of gratings for chirped-pulse-amplified lasers based on near-field and far-field measurements

2009年

作者：匿名

Includes bibliographical references and index.

ISBN: (纸本)1843345811;9781843345817

Includes bibliographical references and index.

关键词： compressors

来源：畅想之星图书光盘版（南... 评论

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Chinese Optics Letters 2011年第4期9卷 67-70页

作者：杨雨川罗晖王逍李富全黄小军冯斌景峰 College of Optic-Electric Science and Engineering National University of Defense Technology Research Center of Laser Fusion China Academy of Engineering Physics

The development of phased-array grating compressor is a crucial issue for high-energy, ultra-short pulse petawatt-class lasers. Almost all systems have adopted a tiled-grating approach to meet the size requirements for the compression gratings. We present a computer-control test system utilizing near-field interference and far-field focusing capable of monitoring and fast correcting tiled errors of the grating compressor. In this system, the tilt/tip errors between the two gratings are determined by the Fourier transform （FT） of the individual interference fringe, and the piston errors are determined by the ratio of the two primary peaks formed in the far-field pattern as a function of the piston difference. Monochromatic grating phasing is achieved experimentally and pulse compression is demonstrated with a tiled grating system.

关键词： compressors Computer control systems Errors Fourier transforms

Demonstration of a 16×10-Gb/s OTDM system

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Chinese Optics Letters 2007年第5期5卷 264-266页

作者：杨彦甫娄采云高以智 Department of Electronic Engineering Tsinghua University

A 16×10-Gb/s optical time-division-multiplexing （OTDM） system was demonstrated experimentally with a well-designed ultrashort pulse source based on an electro-absorption modulator （EAM） and nonlinear fiber compressor. The obtained 10-GHz stable and pedestal-free pulse train has 2-ps width, high extinction ratio, and low timing jitter. An ultrafast demultiplexer based on a nonlinear optical loop mirror （NOLM） including a commercially available highly nonlinear fiber （HNLF） is employed to demultiplex data signal from 160 to 10 Gb/s. A back-to-back error-free demultiplexing experiment is carried out to verify the system performance.

关键词： compressors Mirrors Modulators Optical fibers Timing jitter Ultrashort pulses

Effects of injection frequency on the rotor stall margin

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Science China(Technological Sciences) 2010年第1期53卷 213-219页

作者： ZHOU JunWei,HOU AnPing & ZHOU Sheng National Key Laboratory on Aero-Engines,Beijing University of Aeronautics and Astronautics,Beijing 100191,China National Key Laboratory on Aero-Engines Beijing University of Aeronautics and Astronautics Beijing China

The stall margin of compressor could be improved effectively by rotor tip injection,and the periodic injection is commonly used in the research.The purpose of this work is to investigate the influence of injection frequency on the rotor stall margin.An unsteady CFD code was employed to simulate the flow field of the rotor with injections of different frequencies.Comparing the stall margin of the rotor with injections of different frequencies,it is shown that there is an optimal injection frequency,around which the rotor stability enhancement is the largest.When the injection frequency is away form the optimal frequency,the improvement in stable flow range decreases correspondingly.For the rotor in this paper,the optimal frequency was 1.5 times the frequency of tip leakage vortex(for short,TLV) fluctuation.Time-averaged loading distribution at 98.5% span indicates that the loading of the rotor near the leading edge is decreased through injection with the optimal frequency,and therefore,the stall could be delayed.

关键词： periodic injection axial compressors unsteady flow stall margin tip leakage vortex loading distribution

Best mix of primary energy resources by renewable energy and fossil fuel with CCS in view of security,stability and sustainability——A vision on hydrogen supply chain by organic chemical hydride method

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Science China(Technological Sciences) 2010年第1期53卷 62-68页

作者： Junichi SAKAGUCHI Research Institute of Technology Innovation & Strategy of Chiyoda Corporation 2-12-1TsurumichuoTsurumi-kuYokohama230-8601Japan

The best mix scenario by renewable energy and fossil fuel with or without CCS(Carbon Dioxide Capture and Storage) would be a solution to compromise Greenhouse Gases emission issue caused by carbon dioxide(CO2),and depletion of crude oil and natural gas reserves.As fossil fuel with pre-combustion CCS means hydrogen manufacturing and also hydrogen can be produced via electrolysis with renewable energy,it is desirable to establish transportation and storage systems of hydrogen as a clean energy.In this paper a vision on Hydrogen Supply Chain by Organic Chemical Hydride(OCH) Method as well as comparison of CCS configuration are discussed.

关键词： pre-combustion CCS compressors and pumps for CCS Hydrogen Supply Chain Organic Chemical Hydride Method