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921.
This paper demonstrates that in transition from the one-dimensional longitudinal-channel motion of the coolant in the regenerative cooling system of the liquid propellant engine to the twodimensional (interchannel) channel motion (transpiration) through a porous mesh material (PMM), the hydraulic losses decrease. Experimental data on PMM hydraulic resistance coefficients and heat transfer in porous paths with the interchannel coolant transpiration (ICCT) is presented. 相似文献
922.
F. Dehaeze G. N. Barakos L. I. Garipova A. N. Kusyumov S. A. Mikhailov 《Russian Aeronautics (Iz VUZ)》2017,60(2):198-205
The helicopter main rotor in forward flight is considered in this paper. The results for rigid blades and elastic blades are compared by the method of coupled simulation. The influence of the structural damping coefficient on the blade in-flight deformation is also considered. 相似文献
923.
This paper proposes to solve the problem of determining the strength properties of materials for thin-walled structural elements under mechanical and thermal loading as an optimization problem. A mathematical statement of the problem under certain assumptions is given. 相似文献
924.
S. Z. Sverdlov 《Russian Aeronautics (Iz VUZ)》2017,60(2):163-168
In this paper, it is proposed the flight duration to be assessed by the potential value and the helicopter number. The data on the available power and the relative efficiency for a number of multicopter models are provided. 相似文献
925.
B. A. Antuf’ev 《Russian Aeronautics (Iz VUZ)》2017,60(1):9-12
The paper presents an approximate solution of a problem on dynamic behavior of a wing leading edge assembly discretely reinforced by a system of ribs and coated with thermal protection coating. 相似文献
926.
D. Yu. Kolodyazhnyi V. S. Nagornyi A. M. Sipatov V. Ya. Modorskii 《Russian Aeronautics (Iz VUZ)》2017,60(1):97-102
A technique for calculating the two-phase flows in the pneumatic injector of the aircraft engine is developed based on solving the model problem, namely, on verification of the two-phase flow model by means of solving the problem of liquid column disintegration under the effect of an incident airflow. We determine the turbulence models that satisfactorily describe the biphase flow processes. 相似文献
927.
N. E. Zubov E. A. Mikrin V. N. Ryabchenko A. V. Fomichev 《Russian Aeronautics (Iz VUZ)》2017,60(1):64-73
The problem of lateral motion stabilization is analytically solved for the fourth-order model of aircraft motion using the method of output signal control synthesis that is based on the control object decomposition. Numerical simulation data are presented. 相似文献
928.
With the aim of enhancing the simulation of flow processes and dynamics of aircraft motion, the analysis of the appropriate equations and search for new similarity criteria are carried out. New relations are obtained for the equations of aircraft motion allowing for experiments with overweight models under certain conditions. 相似文献
929.
The paper describes a mathematical model of drop tests on the landing gear of the Ka-62 helicopter. The model is formulated using the multibody system simulation procedure based on the Lagrange equations of the first kind. 相似文献
930.
Features of fuel atomization and propagation in the flow behind a gas-dynamic stabilizer are considered. Estimations of the influence of transverse jets impulse magnitude on characteristics of mixing behind the stabilizer are obtained by numerical and experimental methods. 相似文献