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基于相变复合材料的新型液压油箱设计及研究

兵器装备工程学报 2024年第3期45卷 238-246页

作者：张列李良冯永保何祯鑫韩小霞火箭军工程大学导弹工程学院西安710025

针对液压系统存在“低温启动困难”和“高温散热效率低”的矛盾问题,影响了液压系统设备性能的整体提升。设计一种采用相变复合材料构建的新型液压油箱结构,利用ANSYS软件对先后添加复合相变材料新型油箱进行建模与仿真,得出径向传热、... 详细信息

针对液压系统存在“低温启动困难”和“高温散热效率低”的矛盾问题,影响了液压系统设备性能的整体提升。设计一种采用相变复合材料构建的新型液压油箱结构,利用ANSYS软件对先后添加复合相变材料新型油箱进行建模与仿真,得出径向传热、瞬态传热等仿真云图并进行分析比较传热梯度的变化。仿真结果证实,相变复合材料能够快速吸收油液的热量,从而散热效果高于普通油箱。并且针对油箱传热的不同影响因素进行了仿真分析,得出油箱材料、环境温度、载荷温度仿真云图,仿真结果表明,利用相变复合材料的高储能及高导热特性,在低温条件下,液压油能够在油箱中快速均匀加热以及在高温条件下高效散热,提高油箱的换热效率,减小油箱体积,使其具备“容积小、导热快、换热面积大、油液加热均匀、对极端温度条件适应能力强”等优点,对延长液压油及液压元件的使用寿命,提高液压系统设备的工作可靠性和生存能力具有重要意义。

关键词：相变复合材料液压油箱换热效率瞬态传热数值模拟

重型车辆半主动磁流变悬架系统动态逆自抗扰控制器设计

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振动与冲击 2024年第15期43卷 117-125页

作者：甄亮冯永保李淑智何祯鑫韩小霞火箭军工程大学导弹工程学院西安710025 酒泉职业技术学院甘肃省太阳能发电系统重点实验室甘肃酒泉735000

针对现有重型车辆半主动磁流变悬架系统控制方法受模型中存在非仿射问题和控制增益不确定等问题,提出了一种引入动态逆的线性自抗扰控制器的设计方法。设计了线性扩张状态观测器和动态逆控制器,线性扩张状态观测器估计系统的状态和总和... 详细信息

针对现有重型车辆半主动磁流变悬架系统控制方法受模型中存在非仿射问题和控制增益不确定等问题,提出了一种引入动态逆的线性自抗扰控制器的设计方法。设计了线性扩张状态观测器和动态逆控制器,线性扩张状态观测器估计系统的状态和总和扰动,动态逆用以求解非仿射情况下的控制律。通过仿真试验表明,悬架系统所要求的性能指标明显改善,定量分析得到半主动动态逆线性自抗扰磁流变悬架的车体垂直加速度均方根值与被动悬架和半主动线性自抗扰磁流变悬架相比,分别下降了38.9%、17.8%,悬架动行程下降了7.8%、1.8%,车轮动变形下降了26.5%、11.5%,半主动动态逆线性自抗扰磁流变悬架性能明显优于被动悬架和半主动线性自抗扰磁流变悬架。因此,动态逆线性自抗扰控制技术既解决了重型车辆半主动磁流变悬架系统模型中存在的非仿射问题,同时也避免了经典线性自抗扰控制中控制增益标称值选取困难的问题,可以广泛应用于实际工程中。

关键词：车辆半主动悬架系统磁流变阻尼器动态逆自抗扰控制非仿射系统

Optical Fiber Grating Vibration Sensor for Vibration Monitoring of Hydraulic Pump

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Photonic Sensors 2017年第2期7卷 140-147页

作者： Zhengyi ZHANG Chuntong LIU Hongcai LI zhenxin he Xiaofeng ZHAO Department Two Rocket Force University of Engineering Xi'an 710025 China

In view of the existing electrical vibration monitoring traditional hydraulic pump vibration sensor, the high false alarm rate is susceptible to electromagnetic interference and is not easy to achieve long-term reliable monitoring, based on the design of a beam of the uniform strength structure of the fiber Bragg grating （FBG） vibration sensor. In this paper, based on the analysis of the vibration theory of the equal strength beam, the principle of FBG vibration tuning based on the equal intensity beam is derived. According to the practical application of the project, the structural dimensions of the equal strength beam are determined, and the optimization design of the vibrator is carried out. The finite element analysis of the sensor is carried out by ANSYS, and the first order resonant frequency is 94.739 Hz. The vibration test of the sensor is carried out by using the vibration frequency of 35 Hz and the vibration source of 50 Hz. The time domain and frequency domain analysis results of test data show that the sensor has good dynamic response characteristics, which can realize the accurate monitoring of the vibration frequency and meet the special requirements of vibration monitoring of hydraulic pump under specific environment.

关键词： Fiber Bragg grating uniform strength beam vibrating monitoring vibration sensor

Efficacy of basiliximab in the treatment of 87 cases of steroid-refractory or steroid-dependent acute graft-versus-host disease

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China Medical Abstracts(Internal Medicine) 2022年第2期39卷 121-122页

作者： he zhenxin State Key Experiment hematol Lab Natl Clin Blood Dis Res CenterInstit Hematol&Blood Dis HospCAMS&PUMLTianjin 300020

Objective To evaluate the efficacy and prognosis of basiliximab in the treatment of steroid-refractory or steroid-dependent acute graft-versus-host disease (SR/SDaGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT).Methods Clinical data of 87patients with SR/SD-aGVHD in the skin, intestine, and liver after allo-HSCT at the Institute of hematology&Blood Diseases Hospital Transplantation Center from January 2015 to December 2018 were retrospectively analyzed.

关键词： Blood intestine acute

A novel fiber Bragg grating vibration sensor with double equal-strength cantilever beams

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Optoelectronics Letters 2021年第6期17卷 321-327页

作者： he zhenxin ZHANG Zhengyi LI Liang ZHAN Ying Ml Wenpeng FENG Yongbao Xi’an Research Institute of High Technology Xi’an 710025China High-tech Institute Qingzhou 262500China Rocket Force Unit 96921 Beijing 100000China

In practice,since the measurement environments are usually complex,the electromagnetic interference problem has been an important issue for sensor applications,and the fiber sensor can overcome it *** paper proposes a new type of vibration sensor based on fiber Bragg grating(FBG).The vibration sensor with double equal strength cantilever beams structure can further improve the measurement *** physical model of FBG vibration sensor was established,and the structural parameters of the double equa-strength cantilever beams were designed and optimized by finite element *** simulation and experimental tests are included in this paper to illustrate the low-frequency vibration performance of the designed vibration ***,the sensitivity of the sensor was 0.0240 pm/(m·s^(-2)),the natural frequency was 185 Hz,and the linearity was obtained,which further verify the stability and reliability of the sensor vibration frequency measurement.

关键词： fiber cantilever double

Research on One-Piece Structure Target Flow Sensing Technology Based on Fiber Bragg Grating

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Photonic Sensors 2016年第4期6卷 303-311页

作者： Chuntong LIU Zhengyi ZHANG Hongcai LI zhenxin he Xiaofeng ZHAO Rongjing WU Department Two Rocket Force University of Engineering Xi 'an 710025 China

In view of problems existing in the detection of the traditional hydraulic system, such as the large volume of sensor and the low measurement accuracy, a new one-piece target type flow sensor is designed and researched based on fiber Bragg grating （FBG）. A compact structure is designed, which is convenient to be dismantled, processed, and installed, based on the analysis of the principle of FBG and the structure of target type flow sensor. The force of target put in fluid flow is turned into the FBG wavelength drift, with a corresponding relationship. The problem on the cross sensitivities of the temperature and strain is solved effectively by using double FBG symmetrically pasted on the both surfaces of the cantilever. The impact on the fluid state is analyzed through simulation in the software FLUENT, and the results show that the impact was smaller than that of the traditional structure. The results of experiments in the hydraulic system show that there is a good linear relationship between the change in the dual FBG central wavelength and mass loading on the target sheet has a good linear relationship, and the sensitivity is twice that of a single FBG sensitivity.

关键词： Fiber Bragg grating flow sensor target type structure equal intensity cantilever beam

A novel small-signal equivalent circuit model for GaN heMTs incorporating a dual-field-plate

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Journal of Semiconductors 2024年第5期45卷 61-68页

作者： Jinye Wang Jun Liu zhenxin Zhao School of Integrated Circuit Science and Engineering Hangzhou Dianzi UniversityHangzhou 310018China

An accurate and novel small-signal equivalent circuit model for GaN high-electron-mobility transistors(heMTs)is proposed,which considers a dual-field-plate(FP)made up of a gate-FP and a *** equivalent circuit of the overall model is composed of parasitic elements,intrinsic transistors,gate-FP,and source-FP *** equivalent circuit of the gate-FP is identical to that of the intrinsic *** order to simplify the complexity of the model,a series combination of a resistor and a capacitor is employed to represent the *** analytical extraction procedure of the model parameters is presented based on the proposed equivalent *** verification is carried out on a 4×250μm GaN heMT device with a gate-FP and a source-FP in a 0.45μm *** with the classic model,the proposed novel small-signal model shows closer agreement with measured S-parameters in the range of 1.0 to 18.0 GHz.

关键词： small-signal model dual field-plate(FP) GaN high-electron-mobility transistors(heMT) parameter extraction

Analysis on the turning point of dynamic in-plane compressive strength for a plain weave composite

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Defence Technology（防务技术） 2024年第2期32卷 485-495页

作者： Xiaoyu Wang Zhixing Li Licheng Guo zhenxin Wang Jiuzhou Zhao Department of Astronautic Science and Mechanics Harbin Institute of TechnologyHarbin150001China AECC Commercial Aircraft Engine Co LTDShanghai201108China

Experimental investigations on dynamic in-plane compressive behavior of a plain weave composite were performed using the split Hopkinson pressure bar. A quantitative criterion for calculating the constant strain rate of composites was established. Then the upper limit of strain rate, restricted by stress equilibrium and constant loading rate, was rationally estimated and confirmed by tests. Within the achievable range of 0.001/s-895/s, it was found that the strength increased first and subsequently decreased as the strain rate increased. This feature was also reflected by the turning point(579/s) of the bilinear model for strength prediction. The transition in failure mechanism, from local opening damage to completely splitting destruction, was mainly responsible for such strain rate effects. And three major failure modes were summarized under microscopic observations: fiber fracture, inter-fiber fracture, and interface delamination. Finally, by introducing a nonlinear damage variable, a simplified ZWT model was developed to characterize the dynamic mechanical response. Excellent agreement was shown between the experimental and simulated results.

关键词： Plain weave composite Dynamic strength Quantitative criterion Turning point Failure mechanism

Acculturation and translation:Modern architectural heritage of Zhongshan Park in Xiamen from typological perspective

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Frontiers of Architectural Research 2024年第3期13卷 613-624页

作者： Xufang Li Xiangpin Zhou Feifan Weng Fanzhuo Ding zhenxin Yi Department of Landscape Architecture College of Architecture&Urban PlanningTongji UniversityShanghai 200092China Department of Landscape Architecture College of Landscape Architecture&ArtFujian Agriculture and Forestry UniversityFuzhou 350002China Academy of Art&Design Tsinghua UniversityBeijing 100084China Graduate School of Techno Design Kookmin UniversitySeoulRepublic of Korea

The modern architectural heritage is the core carrier of city’s historical inheritance and *** value is related to the spatial and temporal evolution of the urban landscape,along with the collective memory of society and transformation in public *** contradiction between high-speed urban construction and architectural heritage preservation has proliferated,and the problems of loss of heritage culture and fading of relics are very significant,but there is a lack of research on modern architectural *** study analysed indepth the artistic archetypes and evolutionary characteristics of the architecture of Zhongshan Park in Xiamen through field research and historical data collation,adopting the theory method of architectural ***,we analysed the architectural typology of Zhongshan Park in Xiamen and the process of acculturation and translation with foreign cultures,explored the motives of its formation and the cultural meanings of the public space embodied in *** on this,we proposed a sustainable development heritage approach for the modern architectural heritage of Zhongshan Park in *** results indicate that modern architectural art has inherited classical Chinese historical and cultural traditions and ideological *** unique characteristics reflect the spirit of the times and result from the gradual development of Western ***,it embodies a strong sense of national *** findings enrich the academic research on the cultural interaction between Chinese and Western architecture,offering valuable insights for the conservation and living heritage of modern architectural heritage in other regions.

关键词： Modern architectural heritage Acculturation translation Architectural typology Sun Yat-sen culture Xiamen Zhongshan Park