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Chinese Journal of Aeronautics 2020年第3期33卷 852-860页

作者： Yongqi XIE Xinyu LI sujun dong Hongxing ZHANG Hongwei WU School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China Beijing Key Laboratory of Space Thermal Control Technology China Academy of Space TechnologyBeijing 100094China School of Engineering and Computer Science University of HertfordshireHatfield AL109ABUnited Kingdom

An experimental study was carried out in this article to investigate the transient operating performance of a Dual Compensation Chamber Loop Heat Pipe(DCCLHP) with Thermoelectric Cooler(TEC) under acceleration conditions and ammonia was selected as the working *** the purpose of comparison, experimental work was conducted under terrestrial *** analysis was performed to explore the effect of several control parameters such as the heat load, acceleration magnitude and TEC assist on the startup and operating performance of the *** results indicate that the DCCLHP can get to a steady-state operation when the heat load changes from 25 W to 300 W under terrestrial *** under acceleration conditions, the DCCLHP can work at a high operating temperature or even fail to operate, which shows the acceleration effect plays a significant impact on the loop *** TEC assist with power of 10 W can improve the operating performance and reduce the operating temperature for the case of small heat load and acceleration *** the acceleration exceeds 3 g at large heat load, the effect of TEC assist on the operation at large heat load can be ignored.

关键词： Acceleration Electronic cooling Loop heat pipe Operating performance Thermoelectric cooler

An analytic model for transient heat conduction in bi-layered structures with flexible serpentine heaters

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Applied Mathematics and Mechanics(English Edition) 2021年第9期42卷 1279-1296页

作者： Zhao ZHAO Yuhang LI sujun dong Yi CUI Zheng DAI Institute of Solid Mechanics Beihang UniversityBeijing 100191China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Shanghai Aircraft Design&Research Institute of Commercial Aircraft Corporation of China(COMAC) Shanghai 201210China

Uniform heating of complex surfaces,especially non-developable surfaces,is a crucial problem that traditional rigid heaters cannot *** by flexible electronic devices,a novel design for the stretchable heating film is proposed with the flexible serpentine wire embedded in the soft polymer film,which can be attached to non-developable surfaces *** provides a new way for the stretchable heaters to realize uniform heating of complex ***,the thermal field of flexible serpentine heaters(FSHs)depends on the configurations of the embedded serpentine heating wire,which requires accurate theoretical prediction of real-time temperature ***,the analytical model for the transient heat conduction in FSHs is solved by the separation of variables method and validated by the finite element analysis(FEA)in this *** on this model,the effects of the geometric parameters,such as the radius and the length of the serpentine heaters,on the thermal uniformity are systematically *** study can help to design and fabricate flexible heaters with uniform heating in the future.

关键词： serpentine heater bi-layered structure transient heat conduction temperature distribution

Simulation of an aircraft thermal management system based on vapor cycle response surface model

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Chinese Journal of Aeronautics 2024年第6期37卷 64-77页

作者： Haodong LIU Hongsheng JIANG sujun dong Longxian XUE Yongji LIU Jianjun WU School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Chengdu Aircraft Design and Research Institute Aviation Industry Corporation of ChinaChengdu 610091China

The modern aircraft Thermal Management System(TMS)faces significant challenges due to increasing thermal loads and limited heat dissipation *** optimize TMS during the conceptual design stage,the development of a modeling and simulation tool is *** this study,a TMS simulation model library was created using MATLAB/*** simplify the complexity of the Vapor Cycle System(VCS)model,a Response Surface Model(RSM)was constructed using the Monte Carlo method and validated through simulation *** the F-22 fighter TMS as an example,a thermal dynamic simulation model was constructed to analyze the variation of thermal response parameters in key subsystems and elucidate their coupling ***,the impact of total fuel flow and ram air flow on the TMS was *** findings demonstrate the existence of an optimal total fuel flow that achieves a balance between maximizing fuel heat sink utilization and minimizing bleed air *** adaptive distribution of fuel and ram air flow was found to enhance aircraft thermal management *** study contributes to improving modeling efficiency and enhancing the understanding of the thermal dynamic characteristics of TMS,thereby facilitating further optimization in aircraft TMS design.

关键词： Thermal management sys-tem Vaporcycle Response surface model Dynamic simulation MonteCarlo

Optimization on conventional and electric air-cycle refrigeration systems of aircraft: A short-cut method and analysis

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Chinese Journal of Aeronautics 2020年第7期33卷 1877-1888页

作者： Hongsheng JIANG sujun dong Hainan ZHANG Fengming AI Zhiwei ZHANG Jun WANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Shenyang Aircraft Design and Research Institute Shenyang 110013China

The air-cycle refrigeration system is widely used in commercial and military aircraft,and its efficiency greatly affects aircraft ***,this system requires a more efficient design and optimization *** this paper,a short-cut optimization method with high efficiency and effectiveness is introduced for both conventional and electric air-cycle refrigeration *** on the system characteristics,a four-layer parameter matching algorithm is designed which avoids computational difficulty caused by simultaneous *** penalty is chosen as the objective function of optimization;design variables are reduced based on sensitivity analysis to improve optimization *** results show that the 3-variable optimization of the conventional air-cycle refrigeration system can obtain almost the same results as the traditional 6-variable optimization in that these two optimizations can both significantly reduce the fuel ***,the computer running time of the 3-variable optimization is much shorter than that of the 6-variable *** optimal fuel penalty of the electric air-cycle refrigeration system is lower than that of the conventional *** study can provide reference for optimizing the aircycle refrigeration system of aircraft.

关键词： Aircraft Air-cycle refrigeration Electric air-cycle refrigeration Parameter matching Sensitivity analysis

Experimental investigation on boiling heat transfer characteristics of Al_2O_3-water nanofluids in swirl microchannels subjected to an acceleration force

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Chinese Journal of Aeronautics 2019年第5期32卷 1136-1144页

作者： sujun dong Hongsheng JIANG Yongqi XIE Xiaoming WANG Zhongliang HU Jun WANG School of Aeronautic Science and Engineering Beihang University AVIC Chengdu Aircraft Design and Research Institute School of Chemical and Process Engineering University of Leeds

Experiments were carried out to investigate the boiling heat transfer characteristics of Al_2O_3-water nanofluids in swirl microchannels under terrestrial gravity and acceleration fields. A centrifuge with a two-meter long rotational arm was used to simulate the acceleration magnitude up to 9 g and three various acceleration directions. Three test sections with different geometric parameters were applied. The volume concentration of Al_2O_3 nanoparticles with an average diameter of 13 nm was varied from 0.07% to 0.1%. The mass flow rate and vapor quality were in ranges of 3–6 kg/h and 0.4–1.0%, respectively. The effects of the mass flow rate, microchannel aspect ratio,vapor quality, nanoparticle volume concentration, and acceleration direction and magnitude were analyzed in a systematic manner. Experimental results showed that the acceleration direction and magnitude had significant influences on the boiling heat transfer. The heat transfer under configuration C was found to be superior to that under configurations A and B. Moreover, the heat transfer coefficient increased with increases of the mass flow rate and the volume concentration and decreased with the aspect ratio.

关键词： Acceleration Boiling heat transfer Microchannel Nanofluid Swirl microchannels

STRUCTURE DESIGN OF THE BEIJING SPECTROMETERⅢBEAM PIPE

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Chinese Journal of Mechanical Engineering 2008年第3期21卷 1-6页

作者： ZHENG Lifang JI Quan WANG Li LI xunfeng XU Shaowang dong sujun ZHAO Libin LIU Jianping School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Department of Flight Vehicle Design and Applied Mechanics Beihang University Beijing 100083 China School of Mechanical Engineering Tianjin University Tianjin 300072 China

The Beijing spectrometer Ⅲ （BESⅢ） beam pipe is in the center of the BESⅢ, which is the detector of the upgrade project of Beijing electron and positron collider （BEPC Ⅱ）. Electrons and positrons collide in the BESⅢ beam pipe. According to the demands of the BEPC Ⅱ, a key program of Chinese Academy of Sciences, the BESⅢ beam pipe is designed based on the finite elements analysis. The BESIII beam pipe is installed in the inner cylinder of the BESⅢ drift chamber. As a vacuum tube, the BESIII beam pipe is designed as 1 000 mm in length, 63 mm in inner diameter and 114 mm in outer diameter, respectively. The BESIII beam pipe consists of a central beryllium pipe cooled by EDM-1, the oil No.1 for electric discharge machining, and two extended copper pipes cooled by deionized water （DW）. The three parts are jointed by vacuum welding. Factors taken into account in the design are as follows. ① The wall thickness of the central beryllium pipe should be designed as small as possible to reduce the multi-scattering and improve the particle momentum resolution. And the wall thickness of the extended copper pipe should be designed as large as possible to protect the detectors from the backgrounds. ②The BESⅢ beam pipe must be sufficiently cooled to avoid the damage and prevents its influence to the BESⅢ drift chamber （DC） operation. The inner surface temperature of the DC inner cylinder must be maintained at 293±2 K. ③ The magnetic permeability of the materials used in the BESⅢ beam pipe must be less than 1.05 H/m to avoid large magnetic field distortions. ④ The static pressure of the vacuum chamber of the BESⅢ beam pipe must be less than 800 μPa. The simulating results show that the designed structure of the BESⅢ beam pipe satisfies the requirements mentioned above. The structure design scheme is evaluated and adonted hv the headouarters of BEPCⅡ.

关键词： Beam pipe Beijing spectrometer Ⅲ Structure design Beijing electron and positron collider Ⅱ BESⅢ

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高温燃气风洞加热特性仿真分析

北京航空航天大学学报 2011年第6期37卷 685-689,694页

作者：姚峰董素君王浚北京航空航天大学航空科学与工程学院北京100191

提出了利用亚音速高温燃气流进行近空间高超飞行器热环境地面模拟的试验方案,在试验装置试验段,通过高温高速的燃气流引射低速的冷气流,达到仅使飞行器头锥驻点附近区域产生局部高温而其余头锥蒙皮表面低温的目的.对某型高超音速飞行器... 详细信息

提出了利用亚音速高温燃气流进行近空间高超飞行器热环境地面模拟的试验方案,在试验装置试验段,通过高温高速的燃气流引射低速的冷气流,达到仅使飞行器头锥驻点附近区域产生局部高温而其余头锥蒙皮表面低温的目的.对某型高超音速飞行器的头锥利用高温燃气进行加热并利用CFD(Computational Fluid Dynamics)方法对13种模拟工况进行了数值仿真分析.将数值模拟计算结果与飞行器在高超音速飞行状态下对应机体部位气动热的理论计算值进行了对比,证实了亚声速高温燃气热环境模拟方法的可行性,为高温燃气地面模拟设备技术方案论证提供了依据.

关键词：近空间热环境高超音速飞行器高温燃气数值仿真

基于双模型滤波算法的环控系统换热器故障诊断

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航空学报 2008年第3期29卷 548-553页

作者：庞丽萍曲洪权董素君北京航空航天大学航空科学与工程学院北京100083 北方工业大学信息工程学院北京100041

在建立飞机环控系统数学模型的基础上,提出采用双模型滤波方法进行参数估计、状态预测和故障诊断,提高飞机环控系统故障诊断的快速性和准确性。如果采用最小二乘算法,参数估计是静态的,故障诊断延迟一般较大;采用单模型扩展Kalman滤波算... 详细信息

在建立飞机环控系统数学模型的基础上,提出采用双模型滤波方法进行参数估计、状态预测和故障诊断,提高飞机环控系统故障诊断的快速性和准确性。如果采用最小二乘算法,参数估计是静态的,故障诊断延迟一般较大;采用单模型扩展Kalman滤波算法,虽然能够实现动态估计,但不能同时兼顾稳态过程和过渡过程(突发故障)的参数估计,导致误差较大。为了解决上述难题,针对飞机环控系统换热器故障诊断,提出两模型滤波算法。该算法由两个滤波器组成,分别用于跟踪系统的稳态和过渡过程。由于采用了两滤波器模型分别匹配不同的系统特征,能够改善飞机环控系统不同状态下的参数估计和状态预测性能,从而提高系统故障诊断的精度和速度。仿真结果证实了该算法的有效性。

关键词：飞机环控系统双模型滤波扩展Kalman滤波故障诊断换热器

A new algorithm of global tightly-coupled transient heat transfer based on quasi-steady flow to the conjugate heat transfer problem

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Theoretical & Applied Mechanics Letters 2016年第5期6卷 233-235页

作者： Fanchao Meng sujun dong Jun Wang Dechun Guo School of Aeronautic Science and Engineering Beihang University of Aeronautics and Astronautics Thermal Design Department Beijing Aerospace Technology Research Institute

Concerning the specific demand on solving the long-term conjugate heat transfer （CHT） problem, a new algorithm of the global tightly-coupled transient heat transfer based on the quasi-steady flow field is further put forward. Compared to the traditional loosely-coupled algorithm, the computational efficiency is further improved with the greatly reduced update frequency of the flow field, and moreover the update step of the flow field can be reasonably determined by using the engineering empirical formula of the Nusselt number based on the changes of the inlet and outlet boundary conditions. Taking a duct heated by inner forced air flow heating process as an example, the comparing results to the tightly-coupled transient calculation by Fluent software shows that the new algorithm can significantly improve the computational efficiency with a reasonable accuracy on the transient temperature distribution, such as the computing time is reduced to 22,8% and 40% while the duct wall temperature deviation are 7% and 5% respectively using two flow update time step of 100 s and 50 s on the variable inlet-flow rate conditions.

关键词： Conjugate heat transfer Loosely-coupledQuasi-steady Computational fluid dynamics

板翅式换热器换热效能三元线性回归模型及其系数辨识

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航空学报 2012年第9期33卷 1571-1577页

作者：董素君王凯高红霞王浚北京航空航天大学航空科学与工程学院北京100191 北京航空航天大学人机工效与环境控制重点学科实验室北京100191

针对系统仿真需要,忽略壁面导热热阻和流体物性参数变化,推导出一定对流换热准则形式下,板翅式换热器传热单元数(NTU)与两种流体介质质量流量间的三元线性回归模型。利用少量换热器性能试验数据,以MATLAB内嵌最小二乘法可准确确定该模... 详细信息

针对系统仿真需要,忽略壁面导热热阻和流体物性参数变化,推导出一定对流换热准则形式下,板翅式换热器传热单元数(NTU)与两种流体介质质量流量间的三元线性回归模型。利用少量换热器性能试验数据,以MATLAB内嵌最小二乘法可准确确定该模型系数,进而获得换热效能曲面。对比研究结果表明:该模型不仅试验数据少、拟合精度高,且具有一定的鲁棒性;即使不能准确知道换热器结构参数或传热因子的拟合公式,也能利用少量性能试验数据合理给出换热效能曲面,解决系统仿真研究时换热器模型参数的输入难题。

关键词：线性回归板翅式换热器换热效能系统仿真系数辨识