Mei P.,Beihang University |
Qu W.,Beihang University |
Xue Z.,Beijing Satellite Manufacturing Factory |
Zhuang H.,Beihang University
Cailiao Kexue yu Gongyi/Material Science and Technology | Year: 2015
A large area soldering technology on connecting LD10 aluminum alloy saddle and 1Cr18Ni9Ti stainless steel tube has been researched to solve the hard bonding problem of evaporation. The effects of solder adding method and soldering temperature on the equity of soldering joints have been investigated. The microstructures of joint are analyzed. ANSYS software was used to simulate heat transfer performance of evaporator and analyze the effect of different degrees of soldering defects on heat transfer performance of evaporator. A complete set of the soldering production process of evaporation has been designed finally. ©, 2015, Harbin Institute of Technology. All right reserved.
Zhu X.,Beihang University |
Zheng L.,Beihang University |
Yang F.,Beijing satellite manufacturing factory
Medziagotyra | Year: 2015
Materials of satellite integration truss frame are required to withstand temperature that range from about–250 °C ~ + 150 °C. In order to reduce structural components deformation caused by such temperature change, material of truss frame mostly adopts laminated composite material tubes, whose linear thermal expansion coefficient (LTEC) is very small. Therefore, accurate measurement of LTEC of truss frame materials over a broad temperature range is essential for successful mission. To address this issue, this paper proposes a general experiment platform for measuring LTEC of laminated composite material specimen reaching length up to one meter in the temperature range from–100 °C to +100 °C. The platform uses light-density optical fiber probe to measure length variation and thermocouple to record temperature variation. Thereafter, the thermal expansion coefficient and its measurement uncertainty can be obtained by establishing and solving mathematical model. Finally, LTEC measurement of a tubular composite materials specimen is conducted. The experiment result demonstrates the validity and practicality of the experiment platform and the measurement accuracy of LTEC which can reach up to 10-7/°C. © 2015, Kauno Technologijos Universitetas. All rights reserved.
Liu Y.,Harbin Institute of Technology |
Liu H.,Harbin Institute of Technology |
Wu H.,Beijing Satellite Manufacturing Factory |
Zou D.,Beijing Satellite Manufacturing Factory
Electronics Letters | Year: 2016
A Maxwell model is presented to describe the hysteresis in a piezoelectric actuator. The effect of the number of elements is studied and both of the forward and inverse algorithms are presented. Using the inverse Maxwell model, hysteresis is compensated for and an almost linear performance is obtained. Experimental results validate the effectiveness of the proposed algorithm and show that hysteresis nonlinearity reduces from 13.8 to 0.4%. © The Institution of Engineering and Technology 2016.
Li D.,Wuhan University |
Yan S.,Beijing Satellite Manufacturing Factory |
Lei Y.,Wuhan University |
Xu S.,Wuhan University |
Tan S.,Wuhan University
Diqiu Kexue - Zhongguo Dizhi Daxue Xuebao/Earth Science - Journal of China University of Geosciences | Year: 2016
The core task of the third stage of China's Lunar Exploration Program is to realize the lunar drilling and sampling and returning to the earth. 2-meter-deep lunar soil sampling is required through drilling method. Due to the extreme environment on the lunar surface, an auger core drillig tool with joint inner and outer pipe is proposed in this paper. The core in the inner pipe is obtained by pulling the soft bag, and the core in the outer pipe is transported to the collector by the helical blade. Drilling tests on the lunar soil simulant indicate that the auger drilling tool is reliable for coring, especially for the superficial lunar soil with depth less than 0.6 meters. The influences of drilling parameters on core recovery and drilling power consumption in the tests are studied Relationships between rotation speed, the range of drilling footage speed and power are concluded, which can facilitate the development of core drilling tools and the determination of drilling parameters in the lunar environment. © 2016, Editorial Department of Earth Science. All right reserved.
Qian Y.-B.,Beijing Institute of Technology |
Jiao L.,Beijing Institute of Technology |
Tang D.-H.,Armored Force Engineering Institute |
Sun H.-F.,Beijing Institute of Technology |
He X.-Y.,Beijing Satellite Manufacturing Factory
Beijing Ligong Daxue Xuebao/Transaction of Beijing Institute of Technology | Year: 2010
Face milling process simulation and an error prediction approach are studied. A modified cutting force model is put forward and verified through cutting experiments. A thermo-mechanical finite element model is built up to simulate the complex structural component surface machining process, based on machining process analysis, cutting area discretization, and dynamic cutting loads calculation. Simulated machined surface error is predicted and compared with cutting experiment measurement results, the feasibility and validity of the proposed prediction approach is verified.
Lu Z.,Beijing University of Technology |
Wang L.,Beijing University of Technology |
Chen S.,Beijing University of Technology |
Xue Z.,Beijing Satellite Manufacturing Factory |
And 2 more authors.
Hanjie Xuebao/Transactions of the China Welding Institution | Year: 2012
Variable polarity plasma arc welding process is an important method for welding aluminum alloy. Experimental results show that in addition to current and welding speed, gas flow rate, shrinkage of tungsten and the height of the nozzle are very important parameters which influence weld characteristics. The surface Gauss heat source and the cylinder heat source were selected to simulate the welding temperature field. Through a lot of experiments, the effect of main process parameters on variable polarity plasma arc welding was analyzed. By finite element analysis method, the relation between the heat source model and practical process parameters was established, and through linear regression analysis method mathematical formula was set up.
Kan Z.,Yanshan University |
Guo Z.,Yanshan University |
Zhang C.,Yanshan University |
Meng X.,Beijing Satellite Manufacturing Factory
Proceedings - 2014 International Power Electronics and Application Conference and Exposition, IEEE PEAC 2014 | Year: 2014
As the distributed generators are connected together through inverter interface in the microgrid, the control of the control of the interface inverter has an important influence on the operating performance of microgrid. In the paper, the study focuses on the control of the interfaced inverter, when microgrid operates in the islanded mode. In order to make the microgrid property similar to the utility grid, the ripe control scheme of the utility grid was introduced into the interfaced inverter control; the improvement on the classic droop control was made according to the nature of the low-voltage distribution line. The influence of unequal inverters distribution line impedance on the inverter output power is analyzed in detail, the variable virtual impedance has been proposed. Finally, simulation and experiment results are presented to verify the effectiveness of the proposed control scheme. © 2014 IEEE.
Ye H.-L.,Beijing University of Technology |
Zhao C.-H.,Beijing University of Technology |
Hu T.,Beijing University of Technology |
Xiao Y.-N.,Beijing Satellite Manufacturing Factory
Beijing Gongye Daxue Xuebao/Journal of Beijing University of Technology | Year: 2015
The bending process of the single tape spring was simulated based on ABAQUS software. The variations of critical moment, unfolding moment, and maximum strain energy in the bending process were investigated, and the effects of different radius angles of section and length on driving capability of the simple tape spring was studied by using these parameters. Results show that the driving capability and resisting disturbance capacity grow with the increase of radius angle of section in the bending process of the single tape spring. On the other hand, these capabilities decrease with increasing length of the single tape spring. The research has a certain reference value for improving the kinematic accuracy and reliability of deployable structures. ©, 2015, Beijing University of Technology. All right reserved.
Zhong Y.C.,North China Institute of Aerospace Engineering |
Han W.Z.,North China Institute of Aerospace Engineering |
Liu Y.,Beijing Satellite Manufacturing Factory |
Guo C.,North China Institute of Aerospace Engineering
Advanced Materials Research | Year: 2014
Existing aerospace manufacturing mode is difficult to adapt to the development of industrialization of space transformation in face of the increasing space missions. Then it causes demand for aerospace manufacturing mode transformation. This article first analyzes the present status and transformative driving factor of aerospace manufacturing mode. On the basis of TRIZ theory, we apply the theory of technology evolution in overall space manufacturing mode analysis. Then we look into each specific issues of manufacturing mode and explore the method to solve the problem according to the substance--field analyzing method. After that, integrate all income approaches and seek for target mode which adapts to the transformation of aerospace manufacturing. Finally, the target pattern’s characters are analyzed in terms of the maturity of aerospace products and production process. © (2014) Trans Tech Publications, Switzerland.
Zhou Q.,Beijing University of Technology |
Zhou Q.,Key Laboratory on Deep GeoDrilling Technology of the Ministry of Land and Resources |
Liu B.,Beijing University of Technology |
Liu B.,Key Laboratory on Deep GeoDrilling Technology of the Ministry of Land and Resources |
And 3 more authors.
Procedia Engineering | Year: 2014
In this paper, experiment research on rock impact fragmentation with low power consumption had been carried out. These single-indenter impact experiments on marble had completed discovered the single-indenter impact crushing mechanism under low impact energy of 0.42J ∼ 1.88J. Using three-dimension scanning, the impact crushing crater's precise parameters, including shape, depth and volume, were acquired, and the relation curves between specific energy and impact energy were also gained. These experimental results show that the impact crushing crater's shape generally accords with the Sikarskie shear fracture theory, the crater's depth is less than 0.5mm and the crater's volume is less than 0.5mm3 under0.42J∼1.88J low energy impact loadings. The crater's volume and crushed volume are getting large along with impact energy increasing. However, the specific energy value decreases with impact energy increasing for therangeof0.42J∼1.88J, and the specific energy is most economical when the impact energy is around 1.2J, these results could provide a basis for coring bit designing and parameters optimizing of lunar drilling. © 2014 Published by Elsevier Ltd.