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Numerical Simulations and Analyses of Temperature Control Loop Heat Pipe for space CCD Camera

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Journal of Thermal Science 2016年第5期25卷 402-409页

作者： MENG Qingliang YANG Tao LI Chunlin beijing institute of space mechanics & electricity

As one of the key units of space CCD camera,the temperature range and stability of CCD components affect the image's *** thermal design and robust thermal control devices are *** kind of temperature control loop heat pipe(TCLHP) is designed,which highly meets the thermal control requirements of CCD *** order to study the dynamic behaviors of heat and mass transfer of TCLHP,particularly in the orbital flight case,a transient numerical model is developed by using the well-established empirical correlations for flow models within three dimensional thermal *** temperature control principle and details of mathematical model are *** model is used to study operating state,flow and heat characteristics based upon the analyses of variations of temperature,pressure and quality under different operating modes and external heat flux *** results indicate that TCLHP can satisfy the thermal control requirements of CCD components well,and always ensure good temperature stability and *** comparison between flight data and simulated results,it is found that the model is to be accurate to within 1℃.The model can be better used for predicting and understanding the transient performance of TCLHP.

关键词： Loop heat pipe Temperature control Numerical simulation and analyses Heat and mass transfer space CCD camera

Noiseless Linear Amplification with General Local Unitary Operations

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Chinese Physics Letters 2016年第7期33卷 10-13页

作者：杨颂阮宁娟苏云林栩凌邬志强 beijing institute of space mechanics and electricity

Noiseless linear amplification （NLA）, first proposed by Ralpha et al., is a nondeterministic amplification process which gives gain to the Fock state ｜n） → gn｜n）, with g being the amplification gain. We here give a general frame- work for improving the NLA scheme with arbitrary general local unitary operations. We derive the improvement in the amplification gain in 0 1 photon subspace. In particular, we study if the local unitary is composed of sin- gle mode squeezing and coherent displacement operation. Finally, numerical simulations show that local unitary operation could give a further enhancement in the amplification gain as well as the success probability, making the NLA more feasible in future optic quantum communications.

关键词： NLA on mode in Noiseless Linear Amplification with General Local Unitary Operations of is with

The research of optical windows used in aircraft sensor systems

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Chinese Physics B 2012年第6期21卷 183-187页

作者：周峰李岩汤天瑾 beijing institute of space mechanics&electricity

The optical windows used in aircrafts protect their imaging sensors from environmental effects. Considering the imaging performance, flat surfaces are traditionally used in the design of optical windows. For aircrafts operating at high speeds, the optical windows should be relatively aerodynamic, but a flat optical window may introduce unacceptably high drag to the airframes. The linear scanning infrared sensors used in aircrafts with, respectively, a flat window, a spherical window and a toric window in front of the aircraft sensors are designed and compared. Simulation results show that the optical design using a toric surface has the integrated advantages of field of regard, aerodynamic drag, narcissus effect, and imaging performance, so the optical window with a toric surface is demonstrated to be suited for this application.

关键词： optical window aircraft sensor narcissus effect toric surface

Study on buffering performance of thin-walled metal tube with different angles

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Defence Technology（防务技术） 2018年第6期14卷 702-708页

作者： Qun Liu Wen-tao Wang Wen-feng Zhang beijing institute of space mechanics and electricity BeijingChina

High frequency shock load is often generated during pyrotechnic device working, which is detrimental to spacecraft structures and electric devices. Therefore, it is valuable to reduce the shock load in pyrotechnic device design. Actually, there are several ways to decrease pyroshock loads, such as reduction of powder,installation of buffering structure, insulation of damageable devices, and so on. Considered assuring the function of pyrotechnic device and minimum of structure modification, shock absorbing structure is more propitious to be introduced in pyrotechnic device. In this paper, based on the method of thinwalled metal tube diameter-expanding, a thin-walled tube shock buffering structure was designed on a separate bolt. Built on the simplified structure of a separate bolt, the model of cone piston impacting thin-walled tube absorber was established, and the thin-walled tube shock absorbing characteristics and the relation between cone angles and absorber performance were analyzed. The results showed that the change of buffering force of thin-walled tube could be divided into four phases, and each phase was correspondent to the cone piston structure. In addition, as the cone angle increases, the max shock acceleration changes in the style of decrease-increase-decrease-increase, which is the result of coupled effects of cone piston max enter depth, buffering force and energy loss. In short, these results could establish the relationships between thin-walled tube absorbing performance and its structure, which is of significance to develop low-shock pyrotechnic device.

关键词： Pyroshock Shock absorbing Thin-walled metal tube

Analysis and Verification of Aerodynamic Characteristics of Tianwen-1 Mars Parachute

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space(Science & Technology) 2022年第1期2022卷 219-229页

作者： Mingxing Huang Wenqiang Wang Jian Li beijing institute of space mechanics and electricity Beijing 100094China

The Mars parachute flight environment is supersonic,low-density,and low dynamic *** ensure the operating performance and reliability,the design optimization and verification of the Tianwen-1 Mars parachute have been carried ***,through supersonic and subsonic wind tunnel tests,the design optimization of the parachute structure is ***,the high-altitude flight tests of four parachutes were conducted,the drag coefficient and the oscillation angle of the parachute from supersonic to subsonic speed were gained,and the aerodynamic characteristics and reliable opening of the parachutes were thoroughly tested and *** article presents the design,development,and qualification of the Tianwen-1 Mars parachute,which can provide a reference for the creation of future Mars exploration parachutes.

关键词： subsonic gained altitude

A design of inductosyn angle measurement system based on AD2S80A and FPGA 36

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A design of inductosyn angle measurement system based on AD2...

Design of line-of-sight stabilized control system using inertial and optical-mechanical combined method 36

第36届中国控制会议

作者： SONG Li KANG Jianbing LI Jing beijing institute of space mechanics ＆ electricity

ISBN: (纸本)9781538629185

This paper introduces an inductosyn angle measurement system based on resolver-to digital converter chip AD2S80 A and *** improve the accuracy of angle measurement,a low noise signal process circuit is designed,and amalgamation and compensation of the coarse-fine channels are *** results indicate that the measurement accuracy is within 1 "by using this method,which can satisfy the system requirements of high reliability and accuracy,as well as strong anti-jamming ability.

关键词： inductosyn Amalgamation and compensation of the coarse and fine channels high measurement accuracy

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Design of line-of-sight stabilized control system using iner...

Time-resolved spectroscopy for 5s^('4)D_(7/2) state transitions undergoing electron–ion recombination in femtosecond laser-produced copper plasma

第36届中国控制会议

作者： Huang Gang Lin Zhe Ziyin Chen Jianbing Kang Chunyu Yue beijing institute of space mechanics ＆ electricity

ISBN: (纸本)9781538629185

To improve the stabihty accuracy of stable platform of unmanned aerial vehicle（UAV）,a line-of-sight stabilized control system is developed by using an inertial and optical-mechanical（fast steering mirror） combined method in a closed loop with visual *** system is based on Peripheral Component Interconnect（PCI）,included an image-deviation-obtained system and a combined controller using a PQ *** method changes the series-wound structure to the shunt-wound structure of dual-input/single-output（DISO）,and decouples the actuator range and frequency of inertial stabilization and fast steering mirror *** results show the stability accuracy improves from 20μrad of inertial method to 5μrad of inertial and optical-mechanical combined method,and prove the effectiveness of the combined line-of-sight stabilization control system.

关键词： inertial stability optical-mechanical stability combined line-of-sight stabilization control system stability accuracy

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Chinese Physics B 2017年第12期26卷 290-294页

作者：宋海英李辉张艳杰谷鹏刘海云李维刘勋刘世炳 Strong-field and Ultrafast Photonics Laboratory Institute of Laser Engineering Beijing University of Technology beijing institute of space mechanics and electricity China Academy of Space Technology

In the femtosecond laser-produced Cu-plasma, the transient transition dynamics that the excited state 5s4D7/2 via electron-ion recombination transfers to 4p4F9/20 （465.11 nm, Λ1 line） and 4p4D7/20 （529.25 nm, Λ2 line） states are investigated by using the time-resolved spectroscopy. The occupation number and relevant lifetime of the excited state 5s4D7/2, the temporal evolutions of spectral intensities for Λ1 line and Λ2 line emissions are demonstrated to be in direct proportion to the employed laser intensity, which reveals the transient features of transition dynamics clearly differing from that resulted in the traditional collision excitation. Furthermore, some unique characteristics for Λ1 and Λ2 transitions stemming from electron-ion recombination are examined in detail.

关键词： time-resolved spectroscopy recombination transition laser-produced plasma

Research on the model of high robustness computational optical imaging system

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Chinese Physics B 2023年第2期32卷 264-272页

作者：苏云席特立邵晓鹏 School of Optoelectronic Engineering Xidian UniversityXi'an 710071China beijing institute of space mechanics&electricity Beijing 100094China

Computational optical imaging is an interdisciplinary subject integrating optics, mathematics, and information technology. It introduces information processing into optical imaging and combines it with intelligent computing, subverting the imaging mechanism of traditional optical imaging which only relies on orderly information transmission. To meet the high-precision requirements of traditional optical imaging for optical processing and adjustment, as well as to solve its problems of being sensitive to gravity and temperature in use, we establish an optical imaging system model from the perspective of computational optical imaging and studies how to design and solve the imaging consistency problem of optical system under the influence of gravity, thermal effect, stress, and other external environment to build a high robustness optical system. The results show that the high robustness interval of the optical system exists and can effectively reduce the sensitivity of the optical system to the disturbance of each link, thus realizing the high robustness of optical imaging.

关键词： computational optical imaging high robustness sensitivity