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Journal of Thermal Science 2024年第4期33卷 1421-1442页

作者： QIN Runxuan ZHOU Xun WANG Songtao CAI Le School of Energy Science and Engineering Harbin Institute of Technology

A numerical study is conducted to elucidate the impact of hole shapes and additional flow angles on the flow structure of the coolant and temperature field in the leading edge area of the gas turbine rotor.Four typical hole shapes are considered for the GE-E3 blade.The impact of the additional flow angle(E) within each hole shape on the temperature field is investigated.The results indicate that for the leading edge area and suction surface,the fan-shaped hole case performs best in decreasing temperatures,with a decrease of about 43 K.This is mainly due to the fact that the fan-shaped hole has the maximum expansion in hole spanwise direction.For the pressure surface,the console hole case performs best in decreasing temperatures,with a maximum reduction of about 47.2 K.The influence of E on the surface temperature at leading edge area varied between the different hole shapes.For the cylinder hole and console hole,the E=-20°case has the lowest area-averaged temperature.Because both the fan-shaped hole and the 7-7-7 shaped hole are expansion holes,the pattern of variation of the leading edge area temperature with increasing E is similar for the fan-shaped hole case and 7-7-7 shaped hole case.The E=20°case shows the lowest spanwise-averaged temperature near the hole outlet,and the E=-20°case shows the lowest spanwise-averaged temperature further downstream.

关键词： film cooling GE-E3 turbine rotor blade conjugate heat transfer leading edge

Cooling Performance of the Endwall Vertical Hole Considering the Interaction between Cooling Jet and leading-edge Horseshoe Vortex

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Journal of Thermal Science 2022年第5期31卷 1696-1708页

作者： CHEN Ziyu SU Xinrong YUAN Xin Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Tsinghua UniversityBeijing100084China

Interaction between the coolant and the secondary flow plays an important role in endwall cooling performance.For the leading-edge region,oncoming main flow inside the boundary layer impinges onto the vane leading edge and turns into the horseshoe vortex.Horseshoe vortex entrains coolant off the surface,thus posing severe challenges to the cooling design there.Based on analyses on the leading-edge vortex formation mechanism,a new kind of endwall film cooling design,vertical hole upstream of the saddle point,is proposed to obtain more uniform film coverage over the vane/endwall junction region.Coolant injected from the vertical hole can pass over the horseshoe vortex and impinge around the stagnation line on the vane leading edge.Uniform film coverage can be obtained around the vane leading edge where coolant clings to the endwall surface due to the span-wise pressure gradient of the stagnation region.Numerical simulations are conducted about the cooling performance of two main kinds of both isotropic and anisotropic hole geometries for the endwall and vane surface.Results come that the anisotropic hole shows significant advantages over the isotropic one because it suppresses the symmetrical kidney vortices thus weakening the mixture with high-temperature gas.Blowing ratio(M)effect is analyzed and conclusions are drawn that the cooling performance of the endwall around the leading edge is sensitive to M and adiabatic film cooling effectiveness peaks at about M=2.0.Better cooling performance over the vane corner region can be obtained when M gets even higher while the effective film coverage area shrinks.Apart from that,the phenomenon of phantom cooling on the upper triangular region of the suction surface can be observed when coolant on the endwall is entrained by the vortex formed at the corner of the leading edge.

关键词： film cooling leading edge secondary flow horseshoe vortex

Design and validation of a variable camber wing structure

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Chinese Journal of Aeronautics 2024年第2期37卷 1-11页

作者： Xiasheng SUN Jingfeng XUE Jin ZHOU Zhigang WANG Wenjuan WANG Mengjie ZHANG Chinese Aeronautical Establishment Beijing 100012China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Aircraft Strength Research Institute of China Xi’an 710065China Graduate School of Chinese Aeronautical Establishment Yangzhou 225002China

Variable camber wing technology is one of the important development trends of green aviation at present.Through smooth,seamless,continuous and adaptive change of wing camber,the aerodynamic performance is improved in achieving increase in lift and reduction in resistance and noise.Based on the aerodynamic validation model CAE-AVM,Chinese Aeronautical Establishment(CAE)has carried out the design and validation of a variable camber wing,proposed an aerodynamic deformation matrix for the leading and trailing edges of aircraft wings in takeoff,landing and cruise conditions.Various structures and driving schemes are compared,and several key technology problems of leading and trailing edge deformation are solved.A full-size leading edge wind tunnel test piece with a span of 2.7 m and a trailing edge ground function test piece are developed.The deformation and shape maintenance capabilities of the leading edge is verified under real wind load conditions,and the load bearing and deformation capabilities of the trailing edge is verified under simulated follow-on load.The results indicate that the leading and trailing edges of the variable camber wing can achieve the required deformation angle and have a certain load-bearing capacity.Our study can provide some insights into the application of variable camber wing technology for civil aircraft.

关键词： Variable camber wing leading edge Trailing edge Structure Measurement and control Test

Comparative study of two lay-up sequence dispositions for flexible skin design of morphing leading edge

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Chinese Journal of Aeronautics 2021年第7期34卷 271-278页

作者： Yu YANG Zhigang WANG Shuaishuai LYU Aircraft Strength Research Institute Xi’an 710065China

Morphing leading edge has great potential for noise abatement and aerodynamic efficiency improvement.The drooping effect is realized by bending of the flexible skin which encloses to form the leading edge.Since the flexible skin is often made of composite laminates of Glass Fiber Reinforced Plastics(GFRP),the lay-up sequences have become the determinant,which affects not only the morphing quality but also the manufacturing complexity.Two optimizing methods of layup sequences are comparatively studied.In the first method,the laminal quantities in 0,±45and 90vary independently,while in the second one,the concept of isotropic laminate unit[0/45/45/90]s is employed and the unit quantity is the unique variable.Final evaluation demonstrates that for both methods there is insignificant impact to the overall morphing quality;however,specific concern is equally necessary for these two methods to the tip of the leading edge where the skin is at its minimum thickness and bears the most severe bending deformation.In terms of computational efficiency and post-processing labor,the second method has better performance.

关键词： Composite laminates Flexible skin Glass fiber reinforced plastics Lay-up sequence leading edge Morphing wing

Selection and Impact of an Aerofoil leading edge on Boundary Layer Transition

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Journal of Transportation Technologies 2022年第4期12卷 778-803页

作者： Dinesh Bhatia Devinder Kumar Yadav Guangjun Yang Jian Wang Henrik Hesse School of Aerospace Engineering University of Glasgow Glasgow Singapore School of Aerospace University of Nottingham Ningbo China Ningbo China School of Aeronautics Northwestern Polytechnical University Xi’an China Faculty of Science Engineering and Computing Kingston University London UK

The choice of leading-edge aspect ratio (AR) plays a crucial role when planning boundary layer wind tunnel tests on a flat plate. Poor selection of the leading-edge profile hampers effectiveness of the experiment and increases testing costs associated with interchanging of leading edges to attain accurate results. Thus, the appropriate selection of the leading edge is a very crucial part of the wind tunnel experiment process. It is argued that the curvature of the leading edge and thus the AR is of paramount importance to achieve accurate results from the wind tunnel testing. In this project, seven different elliptical leading edges were tested, and their performance was compared with an ideal leading edge with zero thickness. Experiments and computation have been done for leading edges ranging from AR6 to AR20. Results were evaluated for boundary layer transition onset location, and it was found that AR20 has the least influence on the flow structure when compared to the ideal leading edge. A study of the flow structure at the stagnation point indicates an increase in adverse pressure gradient with an increase in the AR but also shows a decrease in the size of the stagnation region. The presence of a higher AR leading edge reduces the turbulent spot production rate, which is one of the primary causes of boundary layer transition. This paper presents a correlation that enables aerodynamicists to quantify the impact of the leading-edge AR on transition. A typical case is also presented to compare the relative performance of a wedge and the higher AR leading edge, which provides a choice between an elliptical or a wedge-shaped leading edge.

关键词： Boundary Layer Transition leading edge Aspect Ratio Curvature Flow Structure Adverse Pressure Gradient

Numerical investigation on heat transfer in an advanced new leading edge impingement cooling configuration

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Propulsion and Power Research 2015年第4期4卷 179-189页

作者： G.Lin K.Kusterer A.H.Ayed D.Bohn T.Sugimoto R.Tanaka M.Kazari B&B-AGEMA GmbH Aachen D-52070Germany RWTH Aachen University Aachen D-52062Germany Kawasaki Heavy Industries LTD.Gas Turbine&Machinery CompanyAkashi 673-8666Japan Kawasaki Heavy Industries LTD.Technical InstituteAkashi 673-8666Japan

It is known that the leading edge has the most critical heat transfer area of a gas turbine blade.The highest heat transfer rates on the airfoil can always be found on the stagnation region of the leading edge.In order to further improve the gas turbine thermal efficiency the development of more advanced internal cooling configurations at leading edge is very necessary.As the state of the art leading edge cooling configuration a concave channel with multi inline jets has been widely used in most of the blades.However,this kind of configuration also generates strong spent flow,which shifts the impingement off the stagnation point and weakens the impingement heat transfer.In order to solve this problem a new internal cooling configuration using double swirl chambers in gas turbine leading edge has been developed and introduced in this paper.The double swirl chambers cooling(DSC)technology is introduced by the authors and contributes a significant enhancement of heat transfer due to the generation of two anti-rotated swirls.In DSC-cooling,the reattachment of the swirl flows always occurs in the middle of the chamber,which results in a linear impingement effect.Compared with the reference standard impingement cooling configuration this new cooling system provides a much more uniform heat transfer distribution in the chamber axial direction and also provides a much higher heat transfer rate.In this study,the influences of different geometrical parameters e.***.merging ratio of two cylinder channels,the jet inlet hole configurations and radius of blunt protuberances in DSC have been investigated numerically.The results show that in the DSC cooling system the jet inlet hole configurations have large influences on the thermal performance.The rectangular inlet holes,especially those with higher aspect ratios,show much better heat transfer enhancement than the round inlet holes.However,as the price for it the total pressure drop is increased.Using blunt protuberances instead of sharp edges in the DSC cooling can improve the

关键词： Gas turbine Impingement cooling leading edge Double swirl chambers

Flow Field Investigation in a Trapezoidal Duct with Swirl Flow Induced by Impingement Jets

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Chinese Journal of Aeronautics 2011年第1期24卷 8-17页

作者： LIU Haiyong QIANG Hongfu LIU Songling LIU Cunliang 201 Section Xi 'an High- Teeh Institute Xi 'an 710025 China School of Power and Energy Northwestern Polytechnieal University Xi 'an 710072 China

An enlarged model of trapezoidal duct near the leading-edge in the blade is built up. The effects of impingement jets, swirl flow, cross flow and effusion flow are considered. Experiments are performed to measure flow fields in this confined passage and exit holes on one of its side walls. Cross flow and effusion flow are induced in the channel by the outflow of side exit hole （SEH） and film cooling hole （FCH）, which are oriented on one end wall and bottom wall of the passage. Detailed flow structures are measured for two impingement angles of 35° and 45° with 6 combinations of outflow ratios. Results show that the small jets impinge the target wall effectively while the large jets contribute to inducing and impelling a strong counter-clockwise vortex in the upper part of the passage. Cross flow plays a dominate role for the flow structures in the passage and exit holes. It deflects jets, enhances swirl and deteriorates side exit conditions. Impingement angle is another significant factor for the flow characteristics. Its effect reveals more evidently with cross flow. Within the present test conditions, the mass flow rates and outflow positions of FCHs have no distinct effect on the main flow structures.

关键词： flow fields leading edge impingement jets swirl flow film cooling cross flow

让水跳舞的扬声器 leading edge——Water Dancing Speakers White

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微电脑世界 2013年第11期 95-95页

它是市场上最酷,最独特的扬声器。只要将它连接到你的iPod MP3播放器或者个人电脑。你就能看到多种颜色的水流随着音乐的节拍翩翩起舞。该产品兼容任何音频设备,通过一个3.5mm音频插孔进行连接。这款扬声器重量很轻,非常便于携带。

关键词：扬声器喇叭(电子扩音) 电声器件 leading edge Water Dancing Speakers White 让水

A Review of the Attachment Line Instability for Hybrid Laminar Flow Control

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民用飞机设计与研究 2017年第4期 42-51页

作者：张馨元 Shanghai Aircraft Design and Research Institute Shanghai 201210 China

This paper focuses on the investigation of the attachment line instability for Hybrid Laminar Flow Control(HLFC),one of the most promising drag reduction technologies for modern transport aircraft respect to high Reynolds numbers and large sweep angles.The attachment line instability also plays an important role during laminar-turbulent transition control and HLFC design on a swept wing.The overview of historical research is presented and knowledge gaps are pointed out as the conclusion.

关键词： attachment line hybrid laminar flow control(HLFC) boundary layer subcritical instability leading edge