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11.
S I Bartsev V V Mezhevikin V A Okhonin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1996,18(1-2):201-204
Any attempt to create LSS for practical applications must take into account the possibility of castastrophic consequences if the problem of LSS reliability and stability is not solved. An integrated conception of CELSS studies development as a possible way to increase its reliability is considered. The BIOS-4 facility project is developed in the context of the conception. Three principles of highly effective experimental CELSS facility design are proposed. Some details of BIOS-4 design and its exploitation features are presented. 相似文献
12.
P.L. Israelevich A.I. Ershkovich 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1996,17(12):99-103
Plasma and magnetic field disturbances accompanying dust particle impacts are explained by means of creation of a secondary cloud around the spacecraft. Cold cometary ions impinging upon the cloud are scattered by atoms of the cloud. This scattering changes initial angular distribution of cometary ions. Magnetic field perturbation is created by the friction between the electron component of the cometary plasma flow and the cloud. 相似文献
13.
The motion of a spacecraft with small asymmetry relative to its center of mass is considered. The restoring aerodynamic moment of the spacecraft is described by the Fourier series in terms of the angle of attack with the two first sinusoidal and the first cosinusoidal terms. A solution for the angle of attack in the undisturbed rotational motion is found. The analytical expression is obtained for the integral of action taken along the separatrices that separate the rotational and oscillatory regions of the phase portrait of a system. The transition of the spacecraft's motion from planar rotational to oscillatory is investigated. This transition is caused by a slow variation of moment characteristic coefficients, as well as by the presence of small asymmetry and damping and slow variation of their coefficients. Analytical formulas are obtained for determining the times of transition from rotational to oscillatory motion, as well as for the critical angular velocity of beyond-the-atmosphere rotation. When this critical velocity is exceeded, body rotation proceeds for a long time interval (planar autorotation arises). 相似文献
14.
T. K. Sirazetdinov 《Russian Aeronautics (Iz VUZ)》2007,50(1):30-36
A brief review of studies on simulation and control of a porous cooling process taking into account material transpiration is given. An approximated solution for an equation of the one-dimensional problem of fast ablation is also presented. 相似文献
15.
The results of the experimental studies of damping characteristics of a composite torsion bar in the helicopter main rotor
hingeless hub are presented. A variant of their improvement is considered. 相似文献
16.
We present an algorithm for calculating the shells of revolution with the branching meridian using the triangular finite elements, the rigidity matrices of which are formed based on the vector method of displacement interpolation [1]. The correct kinematic and static conditions of shell conjugation on the line of their coupling have been developed. The shell structure consisting of a cylinder and adjacent shells is calculated under various conditions of support. 相似文献
17.
I. S. Akhmed’yanov 《Russian Aeronautics (Iz VUZ)》2009,52(4):383-389
The application of the quadrature method [1] to analyzing the shells of revolution under symmetrical loading relative to the
zero meridian is considered. The method can be treated as a generalization of the method presented in [2] to solve the Volterra
integral equation of the second kind. 相似文献
18.
以小车式起落架为例,利用ADAMS/Airc- raft建立了起落架滑跑试验仿真模型.给出了起落架滑跑运动方程,并进行了滑跑试验仿真分析。仿真结果与理论要求对比具有较好的一致性。 相似文献
19.
A problem of determining a shape of the airfoil being streamlined by a potential incompressible inviscid flow is solved by
the successive approximation method using a specified chord velocity diagram. It is shown that a closed airfoil that possesses
a specified chord velocity diagram can be constructed with a sufficient accuracy; if the chord diagram is unsuccessfully specified,
the closed airfoil may prove to be not univalent, that is, physically unrealizable. 相似文献
20.