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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

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： plasma Nanosecond Pulsed Dielectric Barrier Discharge (NSDBD) flow control flow separation numerical simulation

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

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

Calibration of KEC Value in Acidic Red Soils with Fumigation-Extraction Method

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Pedosphere 2002年第1期12卷 33-40页

作者： chen GUOCHAO and HE zhenli Department of Resource Science, College of Environmental and Resource Sciences, Huajiachi Campus, Zhejiang University, Hangzhou 310029 (China) Department of Resource Science College of Environmental and Resource Sciences Huajiachi Campus Zhejiang University Hangzhou 310029

Commonly used KEC value (0.45) of the fumigation-extraction (FE) method was obtained on the basis of temperate neutral soils. To ascertain its applicability to acidic red soils widespread in southern China and other subtropical regions, the KEC value was investigated based on 8 acidic red soils by in situ labelling of native soil microorganisms using 14C-labelled glucose. Realistic KEC value for red soils could be obtained by in situ 14C-labelling as long as an incubation period of 72 h is adopted after addition of 14C glucose to soil. The single KEC values for the eight red soils ranged from 0.27 to 0.35 and averaged 0.31. Lower KEC value obtained in red soils probably resulted from different soil quality, compared with other types of soil, which causes possible changes in microbial community structure and extractability of cellular component. Microbial biomass C contents of the eight red soils measured using a unique and constant KEC value of 0.45 decreased by 22.2%~40% in comparison to those usin g variable KEC values. The results suggest that microbial biomass C would be significantly underestimated using the present KEC value and a calibration of the KEC value is necessary for red soils.

关键词： calibration in situ 14C-labelling KEC value red soils

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基于面积律概念的超音速减阻设计方法

西北工业大学学报 2006年第4期24卷 523-527页

作者：陈真利张彬乾孙静西北工业大学航空学院陕西西安710072

在分析基于线性理论的跨、超音速面积律设计方法的优点与不足的基础上,依据CFD方法在流场分析和气动力计算方面的优势,提出了面积律概念指导下的CFD技术减阻设计方法。与传统的超音速面积律方法比较,该方法给出了面积律作用的物理原因,... 详细信息

在分析基于线性理论的跨、超音速面积律设计方法的优点与不足的基础上,依据CFD方法在流场分析和气动力计算方面的优势,提出了面积律概念指导下的CFD技术减阻设计方法。与传统的超音速面积律方法比较,该方法给出了面积律作用的物理原因,直接建立了横截面积分布与流场品质之间联系,修形设计目标直观明确、减阻效果明显,且设计工作量小,具有进行复杂外形超音速减阻设计的能力。算例表明,该方法对复杂外形的强约束减阻设计具有很好的适应性,对现役飞机改型是一种工程上简单、易行、外形改动小、结果可靠的修形设计方法;对新型飞机设计具有方案颠覆性小、周期短的优点。具有良好的工程实用性和可操作性。

关键词：超音速减阻设计方法面积律 CFD技术

Surviving And Replicating Inside The Macrophage

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Surviving And Replicating Inside The Macrophage

第十届全国免疫学学术大会

作者： yumei zhou Yuanqiang Zheng Sen Xu Caixia Wang zhenli chen Zhe chen Yanchun Shi Beijing University of Chinese Medicine Inner Mongolia Medical University

Brucella,a gram-negative bacteria,is a highly infectious disease of pandemic potential reporting over 500,000 new human cases *** is the causative agent of the zoonotic disease of brucellosis and it can survive and replicate within the host macrophages,which can escape from the subversion of the immune system to make treatment and diagnosis *** most effective measure to control brucellosis is the vaccination of the host *** are some licensed vaccines for prevention of animals while it is unable to distinguish the vaccinated from the natural infected *** works as the first line of defense of the innate immune response against the invading of *** order to avoid the destruction of macropage,brucella can avoid those defense mechanisms to survive and replicate inside these *** strategies include(1)rapid escape from the phagosome to gain entry into the cytosol;(2)stalling of phagosome maturation at various stages preceding fusion with lysosomes;(3)survival and replication in a degradative phagolysosomal environment.(4)complete or partial avoidance of the *** processes require microbial factors to interfere with macrophage functions,circumvent macrophage defense mechanisms and ensure its intracellular survival over its *** Brucella virulent factors,such as lipopolysaccharide,type IV secretion system and the Bvr R/Bvr S two-component system,have been identified to be critical in the intracellular process of Brucella inside the *** survive in the microphages,brucella have the ability a to control its own intracellular trafficking to avoid lysosomal degradation,multiply extensively within a host cell without restricting basic cellular functions or inducing programmed cell *** this review,I will discuss how the brucella can escape the detection by the host immune system and the mechanism of the brucella surlival and replication in the microphages.

关键词： Brucella Brucellosis Survive Macrophage

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减小翼型激波阻力的鼓包流动控制技术

航空学报 2011年第6期32卷 971-977页

作者：李沛峰张彬乾陈迎春陈真利西北工业大学航空学院陕西西安710072 上海飞机设计研究所上海200232

针对2020年使用的N+2代民用飞机的翼身融合(BWB)布局发展需要,以减小激波阻力为目标,采用计算流体力学(CFD)方法,开展弱化激波、减小激波阻力的鼓包流动控制技术研究。提出了λ形激波结构"强干扰"和等熵压缩"弱干扰"两种鼓包激波减阻流... 详细信息

针对2020年使用的N+2代民用飞机的翼身融合(BWB)布局发展需要,以减小激波阻力为目标,采用计算流体力学(CFD)方法,开展弱化激波、减小激波阻力的鼓包流动控制技术研究。提出了λ形激波结构"强干扰"和等熵压缩"弱干扰"两种鼓包激波减阻流动控制原理,给出了两种鼓包基本形状设计方法和工程应用的可行性分析,指出λ形激波结构鼓包更易于在工程上实现。系统研究了产生λ形激波结构的鼓包位置、高度和长度等参数对控制激波与减小波阻的影响规律,提出了鼓包参数选择原则。研究结果表明,以激波强度和位置为依据,通过鼓包参数优化匹配,可达到弱化激波、减小波阻的目的,减阻效果显著,对RAE2822和NACA0012翼型的最大减阻量分别可达到21%和12%。

关键词：鼓包翼型激波减阻流动控制