Mechanics

Quaternion Models and Algorithms for Solving the General Problem of Optimal Reorientation of Spacecraft Orbit

Authors: Pankratov I. A., Chelnokov Y. N., Sapunkov Y. G.

The problem of optimal reorientation of the spacecraft orbit is considered in quaternion formulation. Control (vector of the acceleration of the jet thrust) is limited in magnitude. To solve the problem it is required to determine the optimal orientation of this vector in space. It is necessary to minimize the duration of the process of reorientation of the spacecraft orbit. To describe the motion of the center of mass of the spacecraft we used quaternion differential equation of the orientation of the spacecraft orbit. The problem was solved using the maximum principle of L. S.

Investigation of Strength and Buckling of Orthotropic Conical Shells and Conical Panels

Authors: Lapina E. O., Semenov A. A.

In the construction, thin-walled shell structures are used to cover the buildings of large areas, such as stadiums, hangars, circuses, airports. In this paper, the strength and buckling of closed conical shells as well as their panels are studied. The geometric nonlinearity and transverse shifts are taken into account. A mathematical model is used in the form of a functional of the total potential energy of deformation. Also expressions for deformations, forces and moments are given. The calculation program is implemented in the MatLab environment.

Thin Film Thermocapillary Motion of Binary Alcohol-Containing Solution

Authors: Ivanova N. A., Borodina K. A.

Interphase convection is a widespread phenomenon that occurs in various branches of technology, including chemical technologies. The greatest interest in the case of thin liquid films is the Marangoni convection. Phase transitions significantly affect the convective flow, changing the coefficient of surface tension. In this paper, the behavior of a thin film of an alcohol-containing solution when it is heated is analytically studied.