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991.
992.
993.
Transfers with a low thrust are considered under constraints imposed on the thrust vector direction. These constraints can be caused by peculiarities of the attitude control system and the mode of stabilization of a spacecraft, and, in the general case, they are functions of the time and state vector. The constraints specified by equalities and inequalities are investigated. It is shown that the optimal thrust is directed along the projection of the Lawden’s primer vector onto the restricting set. 相似文献
994.
N. N. Inozemtsev 《Russian Aeronautics (Iz VUZ)》2010,53(4):443-449
A problem of applying closed multiloop thermodynamic cycles with mixing of dissimilar working gases in spacecraft power plants
has been considered. The advantage of these cycles that is due to reduction of a heat quantity being rejected into space has
been shown for ecologically clean generation of electric energy in prolonged space flights. 相似文献
995.
The mathematical models of the solid-liquid flow regimes in the vertical cylindrical channel are described. A two-speed flow
based on the solid-liquid phase interaction is considered. The problem was numerically solved and the calculation results
were compared with experimental data. 相似文献
996.
A procedure of calculating an axial radial-flow centrifugal stage is considered. Using the gas-dynamically expedient load
ratio distribution in profile, the process of impeller flow passage profiling is described. Also given are some techniques
for decreasing or eliminating a wake zone as well as a graph of loss dependence on the divergence factor and velocity deceleration
on the rarefaction side of the blade channel at the impeller outlet. 相似文献
997.
A comprehensive numerical study of transient interchamber processes occurring when reaching the SPRE operational conditions
is carried out. A conjugate problem under consideration includes nonstationary operation of an igniter heating, ignition and
subsequent nonstationary and turbulent burning of a solid-propellant charge; nonstationary three-phase homo-heterogeneous
flow of combustion products in the combustion chamber, nozzle and downstream of the nozzle block of a rocket engine; motion
of a nozzle block cover. The calculation results are presented. 相似文献
998.
A numerical and analytical method for constructing a shape of the axisymmetric body streamlined with jet blowout by the specified
velocity distribution along its meridian section is proposed. The foundation of the method is the iteration process based
on the solutions of an inverse problem in the plane case and a primal problem for the axisymmetric body. A program realizing
the iteration process is set up and examples of numerical calculations are given. 相似文献
999.
A recursive method for calculating decoupling zeroes in the linear multiconnected dynamic system based on the application
of matrix canonization techniques is proposed. Its essence is that the problem dimension is successively decreased and reduced
to finding eigenvalues of some matrix. The results obtained can be used to check controllability and observability as well
as to calculate uncontrollable and unobservable modes of the dynamic system. 相似文献
1000.
V. R. Rubinskii S. P. Khrisanfov V. Yu. Klimov A. V. Kretinin 《Russian Aeronautics (Iz VUZ)》2010,53(1):81-86
The numerical results are presented for the case of coaxial-jet supply at the different ratio of mass component velocities
at the combustion chamber inlet with the constant and variable relationship of oxygen-methane components. The experimental
investigations of coaxial-jet mixing elements as part of the model setup chamber operating on corrosive producer gas and gaseous
methane were carried out. A qualitative pattern of the $
\overline {\rho u}
$
\overline {\rho u}
parameter influence on the chamber economic feasibility was obtained: as $
\overline {\rho u}
$
\overline {\rho u}
decreases, the combustion efficiency coefficient grows. 相似文献