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Guo P.,China Academy of Launch Vehicle Technology | Liu J.,China Academy of Launch Vehicle Technology | Zhang M.,Beijing Electromechanical Engineering Institute | Yang H.Q.,China Academy of Launch Vehicle Technology
Proceedings of the International Astronautical Congress, IAC | Year: 2014

Hypersonic Reusable Space Vehicle (HRSV) is a kind of reusable space vehicle which can quickly access to the space, maneuver in-orbit, reenter the atmosphere and finally land on the earth ground. Because HRSV has to quickly access to the space and return, its dynamic environment is quite different from the one of traditional launch vehicle, manned spacecraft and recoverable satellite. The internal pressure design should be considered for the safety of vehicle structure. Combining the CFD and quasi one dimensional isentropic flow design methods, the effects of passive gas inflation/deflation system on the internal pressure and pressure loading are studied. The results reveal that the maximum peak value of flight pressure loading induced by the internal and external pressure will appear when the flight height and speed violently change, and the space vehicle structure should be further designed according to the internal pressure and pressure loading results. Copyright © 2014 by the International Astronautical Federation. All rights reserved.

Wang Y.,Dalian University | Bai F.,hiSoft | Wang J.,Beijing Electromechanical Engineering Institute
ICIC Express Letters, Part B: Applications | Year: 2010

The query algorithms for basic nearest neighbor in static environment and an index structure - Time-Parameterized R tree (TPR tree) are introduced in this paper. A concept named influence time is proposed here, which is used in nearest neighbor query algorithm for moving object. The minimum distance calculation in two dimensions and multiple dimensions is discussed. ICIC International © 2010.

Qiao Y.,Hefei University | Chen H.B.,Hefei University | Luo J.L.,Beijing Electromechanical Engineering Institute
Journal of Vibroengineering | Year: 2013

The radiation efficiencies of cylindrical and conical shells were investigated by using the statistical modal energy distribution analysis (SmEdA) and integrated FEM-SmEdA approaches. In cylindrical shell, three analytical algorithms were carried out, including SmEdA and two conventional approaches, i.e. the wave approach and the statistical energy analysis (SEA), and the results were compared with a former experimental one. SmEdA showed closest results with the experimental one, owing to its precise estimation of the coupling loss factors (CLF) which were further used to calculate the radiation efficiency. Furthermore, based on the analytical SmEdA, an integrated FEM-SmEdA algorithm is proposed. This hybrid method provided similar shell radiation efficiency for cylindrical shell, indicating its applicability in the analysis of complicated structures. © VIBROENGINEERING.

Zhang B.,Nanjing University of Aeronautics and Astronautics | Chen H.,Nanjing University of Aeronautics and Astronautics | He X.,Nanjing University of Aeronautics and Astronautics | Chen Y.,Beijing Electromechanical Engineering Institute | And 2 more authors.
Nanjing Hangkong Hangtian Daxue Xuebao/Journal of Nanjing University of Aeronautics and Astronautics | Year: 2012

A vibration experimental system of a cylindric aluminium beam with magneto-rheological(MR) dampers is established. The influence of the MR damper on the structure vibration behaviour is studied, and the vibration reduction is researched. The frequency response functions of the beam with and without the MR dampers under different control voltage are compared. The beam is excited by sine signals and a random signal respectively and the responses are measured with the MR dampers working in different conditions. The research result shows that the MR damper changes the vibration characteristic of the beam only in a narrow frequency domain, and the vibration reduction performance of the MR damper is significant in the low frequency domain but not so effective in the high frequency domain.

Wang J.,Hefei University of Technology | Wang J.,Army Officer Academy of PLA | Chen H.-B.,Hefei University of Technology | Wang J.,Beijing Electromechanical Engineering Institute
Zhendong yu Chongji/Journal of Vibration and Shock | Year: 2013

A new impulsive load identification method in time domain was proposed. With this method, the dynamic loads were assumed to be linear functions within a time-step and the precise time-integration method was used. In this new algorithm, a precise load identification model was constructed, it was not based on a recursion-chain computational format, it was not sensitive to initial values and it had no error cumulation. Furthermore, the TSVD regularization technique was used to overcome the influences of ill-conditioned matrix and measuring noise. Numerical examples showed the effectiveness of the proposed algorithm.

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