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Chinese Journal of Aeronautics 2024年第6期37卷 78-88页

作者： Siyi GUO zhenli chen Xuanyu YAO School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Aero Engine Academy of China Beijing 101304China

Blended-Wing-Body(BWB)aircraft is promoted as one of the most possible layouts to achieve more sustainable civil *** to the non-circular cross-section of the center-body,a bulge deformation forms over the upper surface of the body under the coupled loads of the internal pressurization of the cabin and the aerodynamic bending moments of the wing,which reduces the lift-to-drag ratio of BWB *** a limited deformation,the relationship between the aerodynamic performance and the structural weight needs to be *** this work,the effects of stiffness constraints on the center-body deformation,structural weight of the airframe and aerodynamic performance were investigated by using an analytical model of the Pultruded Rod Stitched Efficient Unitized Structure(PRSEUS)for the airframe and the computational fluid dynamics method,*** results show that as the stiffness constraint increases,the spacings between the rod stringers and the frame stiffeners decrease,and the structural weight increases inversely.A 5.2% reduction of the lift-to-drag ratio is encountered at cruise for a medium deformation design of 42.8 mm/m.A higher aerodynamic penalty is suffered when the stiffness constraint is further *** final deformation criterion is different when the weight vector of the aerodynamic performance and structural weight is different.

关键词： Blended-Wing-Body(BWB) Deformation PultrudedRod Stitched Effi-cient Unitized Structure(PRSEUS) Cabin structure Stiffness constraint

Effects of layer interactions on instantaneous stability of finite Stokes flows

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 69-84页

作者： chen ZHAO zhenli chen C.T.MUTASA Dong LI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

The stability analysis of a finite Stokes layer is of practical importance in flow control. In the present work, the instantaneous stability of a finite Stokes layer with layer interactions is studied via a linear stability analysis of the frozen phases of the base flow. The oscillations of two plates can have different velocity amplitudes, initial phases, and frequencies. The effects of the Stokes-layer interactions on the stability when two plates oscillate synchronously are analyzed. The growth rates of two most unstable modes when δ 0.68. However, the interactions always have a stabilizing effect on the other unstable mode. It is explained that one of the two unstable modes has much higher dissipation than the other one when the Stokes-layer interactions are strong. We also find that the stability of the Stokes layer is closely related to the inflectional points of the base-flow velocity profile. The effects of inconsistent velocity-amplitude, initial phase, and frequency of the oscillations on the stability are analyzed. The energy of the most unstable eigenvector is mainly distributed near the plate of higher velocity amplitude or higher oscillation frequency. The effects of the initial phase difference are complicated because the base-flow velocity is extremely sensitive to the initial phase.

关键词： finite Stokes layer instantaneous stability Stokes-layer interaction asynchronous oscillation

A model for Nanosecond Pulsed Dielectric Barrier Discharge(NSDBD)actuator and its investigation on the mechanisms of separation control over an airfoil

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Science China(Technological Sciences) 2013年第5期56卷 1055-1065页

作者： chen zhenli HAO LinZhao ZHANG BinQian School of Aeronautics Northwestern Polytechnical University

In order to simulate the flow control problem by using Nanosecond Pulsed Dielectric Barrier Discharge(NSDBD),a one-zone inhomogeneous phenomenological model is constructed based on the experimental and theoretical *** model is coupled with the unsteady Navier-Stokes equations,which can well predict the compression-expansion wave structures and wave speed compared with experimental results and can be applied to the simulation of the flow control by using *** model is adopted to investigate the separation control over NACA0015 airfoil using the NSDBD plasma *** separation-control mechanisms are revealed that the spanwise vortices produced by the plasma actuation play the key *** plasma actuation can produce a spanwise vortex around the separation point near the leading *** spanwise vortices make the separated free-shear layer unstable and shed away,move downstream along the upper wall,control the flow near the wall,and bring outer flow with high kinetic energy into the near wall region to realize the effective separation control over the upper surface of the airfoil.

关键词：介质阻挡放电分离控制翼型模型纳秒脉冲 Navier-Stokes方程机制执行器等离子体

Dielectric polymer grafted electrodes enhanced aqueous supercapacitors

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Nano Research 2024年第3期17卷 1525-1534页

作者： Shian Dong Kunming Shi Jie chen Yingke Zhu Hongfei Li Weihang Gao zhenli Xu Qinglei Liu Xingyi Huang Shanghai Key Laboratory of Electrical Insulation and Thermal Aging Department of Polymer Science and EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences Institute of Natural Sciences and MOE−LSCShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China

Supercapacitors(SCs)have become increasingly important in electrical energy storage and delivery owing to their high power densities and long *** SCs are promising for large-scale engineering applications because of their low cost and ***,the low operating voltage and low energy density of aqueous SCs severely limit their practical *** this study,a nanoscale dielectric layer is grafted onto a graphene electrode to achieve both a high operating voltage and enhanced *** with an SC without dielectric grafting,a dielectric-enhanced SC(DESC)shows a higher capacitance by 2200%.The mechanism of the capacitance enhancement can be attributed to three factors:the dielectric polarization,the ions desolvation by the dielectric,and the enhanced quantum capacitance from charge transfer and ion adsorption in the polymer *** addition,a 2.5 V pouch DESC with a 1 M KCl electrolyte is confirmed to cycle up to 50,000 times with a capacitance retention of 87.5%.The DESC presents the optimal electrochemical properties after it is grafted with a 5 nm dielectric *** study provides new insights into the design of high-voltage and high-energy-density aqueous SCs.

关键词： supercapacitors dielectric polymer high voltage capacitance enhancement

Assessment on critical technologies for conceptual design of blended-wing-body civil aircraft

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Chinese Journal of Aeronautics 2019年第8期32卷 1797-1827,1794页

作者： zhenli chen Minghui ZHANG Yingchun chen Weimin SANG Zhaoguang TAN Dong LI Binqian ZHANG School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Shanghai Aircraft Design and Research Institute Commercial Aircraft Corporation of China LtdShanghai 201210China

Civil aviation faces great challenges because of its robust projected future growth and potential adverse environmental effects. The classical Tube-And-Wing(TAW) configuration following the Cayley’s design principles has been optimized to the architecture’s limit, which can hardly satisfy the further requirements on green aviation. By past decades’ investigations the BlendedWing-Body(BWB) concept has emerged as a potential solution, which can simultaneously fulfill metrics of noise, emission and fuel burn. The purpose of the present work is to analyze the developments of critical technologies for BWB conceptual design from a historical perspective of technology progress. It was found that the high aerodynamic efficiency of BWB aircraft can be well scaled by the mean aerodynamic chord and wetted aspect ratio, and should be realized with the trade-offs among stability and control and low-speed performance. The structure concepts of non-cylinder pressurized cabin are of high risks on weight prediction and weight penalty. A static stability criterion is recommended and further clear and adequate criteria are required by the evaluations of flying and handling qualities. The difficulties of propulsion and airframe integration are analyzed. The energy to revenue work ratios of well-developed BWB configurations are compared,which are 31.5% and 40% better than that of TAW, using state-of-art engine technology and future engine technology, respectively. Finally, further study aspects are advocated.

关键词： Aerodynamic design Bended-wing-body Propulsion Airframe Integration Stability and control Structure

Effects of stability margin and thrust specific fuel consumption constrains on multi-disciplinary optimization for blended-wing-body design

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Chinese Journal of Aeronautics 2019年第8期32卷 1847-1859页

作者： Minghui ZHANG zhenli chen Zhaoguang TAN Wenting GU Dong LI Changsheng YUAN Binqian ZHANG School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Shanghai Aircraft Design and Research Institute Commercial Aircraft Corporation of ChinaLtd.Shanghai 200232China

Blended-Wing-Body(BWB) configuration, as an innovative transport concept, has become a worldwide research focus in the field of civil transports development. Relative to the conventional Tube-And-Wing(TAW) configuration, the BWB shows integrated benefits and serves as a most promising candidate for future ‘‘green aviation'. The objective of the present work is to figure out the effects of the stability margin and Thrust Specific Fuel Consumption(TSFC) on the BWB design in the framework of Multi-Disciplinary Optimization(MDO). A physically-based platform was promoted to study the effect static stability margin and engine technology level. Low-order physically based models are applied to the evaluation of the weight and the aerodynamic performance. The modules and methods are illustrated in detail, and the validation of the methods shows feasibility and confidence for the conceptual design of BWB aircrafts. In order to find out the relation between planform changes and the selection of stability and engine technology level, two sets of optimizations are conducted separately. The study proves that these two factors have dominant effects towards the optimized BWB designs in both aerodynamic shapes, weight distribution, which needs to be considered during the MDO design process. A balance diagram analysis is applied to find out a reasonable static stability margin range. It can be concluded that a recommended stability margin of a practical BWB commercial aircraft can be half of that of a conventional TAW design.

关键词： Aerodynamic design Blended-wing-body Multi-disciplinary optimization Optimization design Thrust specific fuel consumption

Nacelle-airframe integration design method for blended-wing-body transport with podded engines

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Chinese Journal of Aeronautics 2019年第8期32卷 1860-1868页

作者： Zhenqing XIN zhenli chen Wenting GU Gang WANG Zhaoguang TAN Dong LI Binqian ZHANG School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Shanghai Aircraft Design and Research Institute Commercial Aircraft Corporation of ChinaLtd.Shanghai 200232China

Strong shock waves and flow separation often occur during the integration of nacelle and airframe for blended-wing-bodies with podded engines. To address this problem, this paper presents an integration method with numerical simulations. The philosophy of channeling flow and avoiding the throat effect on the nacelle and airframe is established based on the analysis of flow interference in the initial configuration. A parametric integration design method is proposed from twodimensional plane to three-dimensional space with control mechanisms and selection principles of the key parameters determined by their influences. Results show that strong shock waves and flow separation can be successfully eliminated under the influence of both the reshaped channel and decelerated inflow below the nacelle. Supersonic regions around the nacelle are effectively reduced, concentrating mainly on the lip position. Thus, a significant cruise drag reduction(8.7%) is achieved though the pressure drag of the nacelle increases.

关键词： Blended-wing-body Computational fluid dynamics Drag reduction Flow interference Nacelle-airframe integration

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极低出生体重儿PICC后静脉炎的影响因素

中外女性健康研究 2022年第10期 196-198页

作者：陈珍丽安徽省妇幼保健院新生儿科安徽合肥230001

目的:研究极低出生体重儿PICC后静脉炎的影响因素。方法:回顾性分析本院2016年1月至2021年7月行PICC的150例极低出生体重儿的临床资料。查看PICC后静脉炎的发生情况,采用单因素及多因素分析患儿PICC后发生静脉炎的影响因素。结果:150例... 详细信息

目的:研究极低出生体重儿PICC后静脉炎的影响因素。方法:回顾性分析本院2016年1月至2021年7月行PICC的150例极低出生体重儿的临床资料。查看PICC后静脉炎的发生情况,采用单因素及多因素分析患儿PICC后发生静脉炎的影响因素。结果:150例行PICC的极低出生体重儿,发生静脉炎22例,发生率为14.67%。发生静脉炎与未发生静脉炎患儿的胎龄、出生体质量、置管时间、穿刺次数、置管长度对比,差异有统计学意义(P0.05)。将极低出生体重儿胎龄、出生体质量、置管时间、穿刺次数、置管长度纳入作为自变量,经单项Logistic回归分析及校正各个资料带来的影响后,多因素分析结果:显示,胎龄小、出生体质量低、置管时间长、穿刺次数多、置管长度大均是极低出生体重儿PICC后发生静脉炎的影响因素(P<0.05)。结论:极低出生体重儿PICC后发生静脉炎的危险因素包括胎龄小、出生体质量低、置管时间长、穿刺次数多、置管长度大,通过早期分析上述风险因素积极采取应对措施,可能降低静脉炎发生率,改善患儿预后。

关键词：极低出生体重儿 PICC 胎龄静脉炎

脉冲表面电弧放电对高超声速压缩拐角的非定常控制机理

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航空学报 2023年第12期44卷 91-107页

作者：丁博陈真利焦子涵王锦程李铮白光辉西北工业大学航空学院西安710072 中国运载火箭技术研究院空间物理实验室北京100076

近年来较多试验研究结果表明脉冲表面电弧放电等离子体对高超声速流动中激波位置和激波/边界层干扰有较好的控制能力。由于短放电时间、强电磁干扰和有限的放电区域,使得试验定量测量非常困难,多数试验仅获得了定性的纹影试验结果。为... 详细信息

近年来较多试验研究结果表明脉冲表面电弧放电等离子体对高超声速流动中激波位置和激波/边界层干扰有较好的控制能力。由于短放电时间、强电磁干扰和有限的放电区域,使得试验定量测量非常困难,多数试验仅获得了定性的纹影试验结果。为揭示脉冲表面电弧放电等离子体高超声速流动非定常控制机理,需要建立表面电弧放电等离子体与高超声速流动相互作用数值模拟方法。采用数值模拟和试验相结合的方法研究了脉冲表面电弧放电等离子体对高超声速压缩拐角流动的非定常控制机理。在理论分析和试验的基础上,建立了脉冲表面电弧放电唯象学模型,即将电弧放电产生的焦耳热作为空间功率密度源项添加到能量方程中,模拟脉冲表面电弧放电等离子体与高超声速压缩拐角流动之间的相互作用。与试验结果对比分析表明,不同时刻数值模拟纹影与试验纹影吻合,能较准确模拟电弧丝与流动之间的相互作用过程,验证了唯象学模型的正确性。非定常数值模拟结果揭示了电弧放电等离子体与双楔高超声速流动相互作用机理:表面电弧放电产生的局部焦耳热诱导形成近壁分离区,导致局部位移厚度增加,形成沿壁面移动的非定常虚拟楔,从而产生激波角随时间变化的斜激波,并与前楔激波之间形成包括激波反射在内的非定常激波/激波相互作用。放电形成的热气体团对后楔斜激波具有明显调控能力。在单脉冲放电控制过程中,最大减阻量约2%,最大俯仰力矩变化量约3%。

关键词：表面电弧放电等离子体流动控制高超声速流动唯象学模型非定常控制

氧化物协同改性对有机硅树脂抗烧蚀性能的影响

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塑料 2024年第2期53卷 41-44,51页

作者：王彬丁振礼陈永彬山东航空学院机电工程学院山东滨州256600 滨州渤海活塞有限公司山东滨州256606

为改善树脂基热防护材料的抗烧蚀性能,采用氧化硼和氧化钛作为填料,对环氧改性有机硅树脂进行协同改性,制备了改性复合材料。分析了氧化硼和氧化钛协同改性对复合材料抗烧蚀性能、力学性能和热稳定性的影响。结果表明,添加氧化硼和氧化... 详细信息

为改善树脂基热防护材料的抗烧蚀性能,采用氧化硼和氧化钛作为填料,对环氧改性有机硅树脂进行协同改性,制备了改性复合材料。分析了氧化硼和氧化钛协同改性对复合材料抗烧蚀性能、力学性能和热稳定性的影响。结果表明,添加氧化硼和氧化钛后,复合材料的拉伸强度、密度和硬度大幅提高,热解失重显著减小,复合材料的马弗炉静态烧蚀和氧-乙炔烧蚀性能有效提升。在高温氧-乙炔烧蚀条件下,氧化硼和氧化钛的复合添加,能够在复合材料表面形成颗粒状与羽毛状的协同改善多孔结构,显著提升了复合材料的抗烧蚀性能,其线烧蚀率低至0.12 mm/s,与改性前相比,降幅超过75%。

关键词：环氧改性有机硅协同改性烧蚀性能氧化硼氧化钛