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Micromanufacturing technologies of compact heat exchangers for hypersonic precooled airbreathing propulsion: A review

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Chinese Journal of Aeronautics 2021年第2期34卷 79-103页

作者： bao meng Min WAN Rui ZHAO Zhengping ZOU Huoxing LIU School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBeijing 100191China

The Hypersonic Precooled Combined Cycle Engine(HPCCE), which introduces precooler into traditional hypersonic engine, is regarded as the most promising propulsion system for realizing a single-stage-to-orbit vehicle. The unique demands lead to the application of the compact heat exchangers, which can realize high thrust-to-weight ratio, sufficient specific impulse and high compression ratio. However, it is challenging to accurately manufacture the compact heat exchanger due to its extremely high heat dissipation capacity, remarkable compactness, superior adaptability and harsh operating condition. This review summarizes the precooling schemes of combined cycle propulsions and describes the demands and key issues in the fabrication of a compact heat exchanger for HPCCE. The investigation focuses on the application of various micromanufacturing methods of heat exchangers constructed from tubes of less than 1 mm in diameter and microchannels of less than 200 micrometers. Various micromanufacturing processes, which include microforming, micromachining, stereolithography, chemical etching, 3 D printing, joining and other advanced microfabricating processes, were reviewed. In addition, the technologies are compared in terms of dimensional tolerance, material compatibility, and process applicability. Furthermore, the boundaries of the micromanufacturing constraints are specified as references for the design of compact heat exchangers. Ultimately, the technological difficulties and development trends are discussed for the fabrication of compact heat exchangers for HPCCE.

关键词： Compact heat exchangers Hypersonic precooled engine Microchannels Micromanufacturing Microtube

Feasibility evaluation of failure models for predicting forming limit of metal foils

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Chinese Journal of Aeronautics 2020年第9期33卷 2461-2471页

作者： bao meng Jiejie SHI Yiyun ZHANG Cheng CHENG Bolin MA Min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100083China

Forming limit of metal foil is an important index to evaluate its formability,and is of considerable significance to improve the quality of *** ductile fracture(DF)behavior in microscale plastic deformation is remarkably affected by the geometry and grain *** explore the size-dependent forming limit curve(FLC),the Holmberg and Marciniak tests of SUS304 foils with the thicknesses of less than 0.1 mm and diverse grain sizes were *** addition,the validity and feasibility of three types of existing failure models including Swift/Hill,MarciniakKuczynski(M-K)and DF criteria for predicting the micro-scaled FLCs were *** is found that the Swift/Hill model possesses the worst accuracy with predicting deviation above 50%.Four classical DF criteria including Freudenthal,Ayada,Brozzo and Oh show great difference,and Oh model considering plastic anisotropy presents the best *** predicted deviation of M-K model is aggravated with increasing grain size and decreasing foil thickness,which is attributed to the intensified free surface roughening and transformation of fracture mechanism with *** research thus provides a deeper understanding and valuable reference for the widespread application of FLC in microforming.

关键词： Failure criteria Forming limit Metal foil Microforming Size effect

Inner wrinkling control in hydrodynamic deep drawing of an irregular surface part using drawbeads

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Chinese Journal of Aeronautics 2014年第3期27卷 697-707页

作者： meng bao Wan Min Wu Xiangdong Yuan Sheng Xu Xudong Liu Jie School of Mechanical Engineering and Automation Beihang University Department of Manufacturing Engineering Chengdu Aircraft Industrial Corporation Sheet Metal Manufacturing Plant Chengdu Aircraft Industrial Corporation

Inner wrinkling phenomenon is more likely to develop during hydrodynamic deep drawing （HDD） of complicated component-forms due to the higher demand for controlling deformation sequences. Aiming at the problems in control of inner wrinkling for an irregular surface part featured with both concavity and convex, this research proposes an optimal design method of drawbead parameters to change the material flow. According to theoretical analysis of the mechanism of inner wrinkling, optimizing cavity pressure only is unreasonable to form a wrinkle-free deep-drawn part, so semi-circular drawbeads are employed. The effects of layout and height of drawbeads on forming results are discussed, and a process window is established based on evaluation indicators including the anti-wrinkle coefficient and the minimum wall thickness. Experiments are carried out to validate the process window, and the wall thickness and the wrinkle height are measured and compared with numerical findings. The results show that the anti-wrinkle ability of drawbeads weakens with increasing oblique angle and distance from the die center, while the wall thickness increases with increasing oblique angle and distance, and the inner wrinkling can be completely suppressed by drawbeads arranged in zones I and II with optimum penetration.

关键词： Aircraft part manufacturing Drawbead Hydrodynamic deep drawing Irregular surface part Numerical simulation Sheet metal Wrinkling

Role of bedding planes played in enhancing dissolution in sandstones

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Frontiers of Earth Science 2022年第3期16卷 587-600页

作者： Jin LAI Xiaojiao PANG meng bao Bing WANG Jianan YIN Guiwen WANG Xuechun FAN State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China

Diagenesis exerts an important control on porosity evolution,and research of diagenesis and diagenetic minerals provides insights into reservoir quality evaluation and CO_(2) *** section,XRD(X-ray diffraction),CT(Computed Tomography),scanning electron microscopy(SEM),and NMR(Nuclear Magnetic Resonance)tests were used to investigate composition,texture,pore spaces,and diagenesis of sandstones in Paleogene Dongying Formation in Bohai Bay Basin,China,with special aims to unravel diagentic dissolution along bedding *** oversized pores,remnants in feldspar-hosted pores,and kaolinite within feldspar grains indicate a high degree of dissolution the framework grains experienced during *** CO_(2)-rich or organic acids are responsible for the feldspar *** size plays the primary role in enhancing bedding dissolution process,and bedding planes in fine-medium grained sandstones with high content of feldspars are frequently enlarged by *** CT scanning image confirms dissolution pores are distributed discontinuously along the bedding *** dissolution pores along bedding planes have large pore size,and correspond to the right peak of the bi-modal T_(2)(transverse relaxation time)*** laminated sandstones and siltstones,or sandstones with cross beddings help improve framework grain *** new findings help improve the understanding of diagenetic models,and have implications in reservoir quality prediction and resource assessments in sandstones.

关键词： dissolution sandstones diagenesis bedding plane Dongying Formation

Analytical model of tilted driver–pickup coils for eddy current nondestructive evaluation

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Chinese Physics B 2018年第3期27卷 125-131页

作者： Bing-Hua Cao Chao Li meng-bao Fan Bo Ye Gui-Yun Tian School of Information and Control Engineering China University of Mining and TechnologyXuzhou 221116China jiangsu Key Laboratory of Mine Mechanical and Electrical Equipment China University of Mining and TechnologyXuzhou 221116China School of Mechatronic Engineering China University of Mining and TechnologyXuzhou 221116China Faculty of Information Engineering and Automation Kunming University of Sciance and TechnologyKunming 650500China School of Electrical and Electronic Engineering Newcastle UniversityNewcastle upon Tyne NE17RUUK

A driver-pickup probe possesses better sensitivity and flexibility due to individual optimization of a *** is fre-quently observed in an eddy current(EC)array *** this work,a tilted non-coaxial driver-pickup probe above a multilayered conducting plate is analytically modeled with spatial transformation for eddy current nondestructive ***,the core of the formulation is to obtain the projection of magnetic vector potential(MVP)from the driver coil onto the vector along the tilted pickup coil,which is divided into two key *** first step is to make a projection of MVP along the pickup coil onto a horizontal plane,and the second one is to build the relationship between the pr,ojected MVP and the MVP along the driver ***,an analytical model for the case of a layered plate is established with the reflection and transmission theory of electromagnetic *** calculated values from the resulting model indicate good agreement with those from the finite element model(FEM)and experiments,which validates the developed analytical model.

关键词： nondestructive evaluation eddy currents tilted coils analytical model

Modeling the carbon dynamics of alpine grassland in the Qinghai-TibetanPlateau under scenarios of 1.5 and 2 ℃ global warming

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Advances in Climate Change Research 2019年第2期10卷 80-91页

作者： YI Shu-Hua XIANG Bo meng bao-Ping WU Xiao-Dong DING Yong-Jian Instiute o f Fragile Ecosystem and Environment Nantong University Nantong 226007 China of Geographic Sciences Nantong University Nantong 226007 China State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China Chongqing Climate Center Chongqing 401147 China Cryosphere Research Station on the Qinghai-Tibetan Plateau Lanzhou 730000 China Key Laboratory of Ecohydrology of Inland River Basin Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy Sciences Beijing 100049 China

Alpine grassland occupies two-thirds of the Qinghai-Tibetan Plateau (QTP). It is vital to project changes of this vulnerable ecosystem under different climate change scenarios before taking any mitigation or adaptation measures. In this study, we used a process-based ecosystem model, driven with output from global circulation models under different Representative Concentration Pathways (RCPs), to project the carbon dynamics of alpine grassland. The results showed the following: 1) Vegetation carbon (C) on the QTP increased by 22—38 gC m^-2 during periods of 1.5 and 2 ℃ warming under different RCPs when compared to the baseline period (1981—2006), while soil C increased by 85—122 gC m^-2. 2) The increases of vegetation C and soil C at the period of 1.5 ℃ warming were about 15 gC m^-2 and 40 gC m^-2 smaller than those at the period of 2 ℃ warming, respectively;increase of C was greater for alpine meadow than for alpine steppe. 3) Precipitation, radiation, and permafrost changed significantly and showed heterogeneous spatial patterns, and caused heterogeneous response of C dynamics. For alpine meadow in regions transformed from permafrost to seasonally frozen soil with medium annual precipitation (200—400 mm), vegetation C and net primary production decreased by 18.7 gC m-2 and 3.1 gC m^-2 per year during 2 °C warming under RCP 4.5, respectively. This decrease can be attributed to the disappearing impermeable permafrost. Different from previous studies that indicated an unfavorable response of alpine grassland to climate warming, this study showed a relatively favorable response, which is mainly attributed to C 0 2 fertilization.

关键词： Permafrost Terrestrial ecosystem model Vegetation Soil Net primary production

Synthesis of an antimetastatic tetrasaccharide β-D-Gal-(1→4)-β-d-GlcpNAc-(1→6)-α-D-Manp-(1→6)-β-D-Manp-OMe

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Chinese Chemical Letters 2012年第12期23卷 1371-1374页

作者： Kai Jun Liao Xiao Feng Jin Xiang bao meng Chen Li Zhong Jun Li State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking University

An antimetastatic tetrasaccharide β-D-Gal-（1 → 4）-β-D- GlcpNAc-（1 →6）-α-D-Manp-（1 → 6）-β-D-Manp-OMe, was syn- thesized with two approaches. The first approach was a conventional method employing thioglycoside and Koenigs-Knorr glycosylation reaction in 24% overall yield. The second one was a novel route through the azidoiodo-glycosylation strategy by using 2-iodo-2-deoxylactosyl azide as the donor in 36% overall yield.

关键词： Antimetastatic tetrasaccharide Thioglycoside Koenigs-Knorr method Azidoiodo-glycosylation 2-Iodo-2-deoxyl-actosyl azide β-Methyl mannoside

Geological and Engineering‘Sweet Spots'in the Permian Lucaogou Formation,Jimusar Sag,Junggar Basin

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Acta Geologica Sinica(English Edition) 2023年第4期97卷 1214-1228页

作者： LAI Jin BAI Tianyu LI Hongbin PANG Xiaojiao bao meng WANG Guiwen LIU Bingchang LIU Shichen National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing 102249China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China

Unconventional oil and gas resources require petrophysical logs to answer the question of how best to optimize geological and engineering‘sweet spots'.Therefore,the establishment of a key well with comprehensive descriptions of lithology,reservoir properties,hydrocarbon-bearing properties,electronic well log responses,source rock properties,brittleness,and in situ stress magnitude and direction is important for the effective exploration and production of unconventional hydrocarbon ***,thin sections,scanning electron microscopy(SEM)and comprehensive well log suites are used to build a key well for the Permian Lucaogou Formation,Jimusar Sag of the Junggar *** results show that there are three main types of lithologies,including siltstone,mudstone and *** can be predicted using the combination of conventional well and image *** pore spaces consist of interparticle pores,intragranular dissolution pores and *** Magnetic Resonance(NMR)T_(2)components longer than 1.7 ms are superposed as effective *** is calculated using the Coates model from NMR T_(2)*** ratio of T_(2)components>7.0 ms to T_(2)components>0.3 ms is used to calculate oil *** is calculated using theΔlog R *** index is calculated using Poisson-Young's method,ranging from 13.42%-70.53%.In situ stress direction is determined,and in situ stress magnitudes(maximum horizontal stress SH_(max),minimum horizontal stress Sh_(min),vertical stress S_(v))are calculated using density and sonic *** strike-slip stress type(SH_(max)>S_(v)>Sh_(min))is *** key well which comprehensively includes the above seven properties is *** and engineering(geomechanical)‘sweet spots'are then optimized from the key well by fully analyzing lithology,reservoir property,oilbearing potential,in situ stress magnitude and *** is hoped that the results support engineers'and geologists'decisions

关键词： key well unconventional oil and gas resources ‘sweet spot' well logs Lucaogou Formation Jimusar Sag

Bedding parallel fractures in fine-grained sedimentary rocks:Recognition,formation mechanisms,and prediction using well log

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Petroleum Science 2022年第2期19卷 554-569页

作者： Jin Lai Bing-Chang Liu Hong-Bin Li Xiao-Jiao Pang Shi-Chen Liu meng bao Gui-Wen Wang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China

Core,thin section,conventional and image logs are used to provide insights into distribution of fractures in fine grained sedimentary rocks of Permian Lucaogou Formation in Jimusar *** parallel fractures are common in fine grained sedimentary rocks which are characterized by layered *** and thin section analysis reveal that fractures in Lucaogou Formation include tectonic inclined fracture,bedding parallel fracture,and abnormal high pressure *** parallel fractures are abundant,but only minor amounts of them remain open,and most of them are partly to fully sealed by carbonate minerals(calcite)and *** parallel fractures result in a rapid decrease in resistivity,and they are recognized on image logs to extend along bedding planes and have discontinuous surfaces due to partly-fully filled resistive carbonate minerals as well as late stage dissolution.A comprehensive interpretation of distribution of bedding parallel fractures is performed with green line,red line,yellow line and blue line representing bedding planes,induced fractures,resistive fractures,and open(bedding and inclined)fractures,*** strike of bedding parallel fractures is coinciding with bedding *** parallel fractures are closely associated with the amounts of bedding planes,and high density of bedding planes favor the formation of bedding parallel *** dark and bright layers have the most abundant bedding parallel fractures on the image logs,and the bedding parallel fractures are always associated with low resistivity *** results above may help optimize sweet spots in fine grained sedimentary rocks,and improve future fracturing design and optimize well spacing.

关键词： Bedding parallel fracture Fine-grained sedimentary rocks Image logs Lucaogou Formation