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711.
R. N. Faizutdinov I. O. Spiridonov A. A. Baloev S. M. Chernyavskii 《Russian Aeronautics (Iz VUZ)》2017,60(4):551-558
A technique of multiobjective parametric design of line-of-sight stabilization system for an airborne electro-optical device is developed. The multiobjective design of the PI controller for the stabilization system being considered is performed. 相似文献
712.
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
713.
M. I. Panasyuk M. V. Podzolko A. S. Kovtyukh I. A. Brilkov N. A. Vlasova V. V. Kalegaev V. I. Osedlo V. I. Tulupov I. V. Yashin 《Cosmic Research》2017,55(2):79-87
The Earth’s radiation belts discovered at the end of the 1950s have great scientific and practical interest. Their main characteristics in magnetically quiet periods are well known. However, the dynamics of the Earth’s radiation belts during magnetic storms and substorms, particularly the dynamics of relativistic electrons of the outer belt, when Earth’s radiation belt particle fluxes undergo significant time variations, is studied insufficiently. At present, principally new experiments have been performed and planned with the intention to better study the dynamics of the Earth’s radiation belts and to operationally control the space-energy distributions of the Earth’s radiation belt particle fluxes. In this paper, for spacecraft designed to measure the fluxes of electrons and protons of the Earth’s radiation belts at altitudes of 0.5–10000 km, the optimal versions for detector orientation and orbital parameters have been considered and selected. 相似文献
714.
M. I. Panasuyk V. V. Kalegaev I. N. Myagkova N. V. Kuznetsov M. V. Podzolko 《Cosmic Research》2017,55(6):464-468
Factors of radiation environment in near-Earth space in a period from December 1 to 10, 2014 have been analyzed, which could affect serviceability of the onboard systems of Vernov spacecraft. 相似文献
715.
Analysis of errors in atmospheric density measurements by lidar on board the ISS is performed. It is shown that using as the lidar transmitter a Nd:YAG laser with moderate parameters of emission at a wavelength of 353 nm and a receiving mirror diameter of 0.4 m, it is possible to cover with a 10% measurement error a height range, on average, from 40–60 km and 30–40 km in the nighttime and daytime, respectively, down to the troposphere. Working with emission at 266 nm with a 10% error, it is possible to move to the heights of the mesosphere (70 km) and penetrate the atmosphere down to a height of 40 km. Thus, the use of two harmonics makes it possible to assimilate the height range of atmospheric density measurements from on board the ISS beginning from 70 km and down to the troposphere. 相似文献
716.
V. M. Gureev A. Kh. Khairullin F. A. Varlamov I. F. Gumerov R. Kh. Khafizov 《Russian Aeronautics (Iz VUZ)》2016,59(4):554-558
This paper considers the problem of reducing the nitrogen oxide emissions in exhaust gases (EG) of the diesel aircraft engine by exhaust gas recirculation (EGR). The main directions in improving a working process of diesel engines with EGR system were formulated. 相似文献
717.
Elkin I.GUTIRREZ VELSQUEZ 《中国航空学报》2017,30(5)
Performance prediction in preliminary design stages of several turbomachinery components is a critical task in order to bring the design processes of these devices to a successful conclusion.In this paper,a review and analysis of the major loss mechanisms and loss models,used to determine the efficiency of a single stage centrifugal compressor,and a subsequent examination to determine an appropriate loss correlation set for estimating the isentropic efficiency in preliminary design stages of centrifugal compressors,were developed.Several semi-empirical correlations,commonly used to predict the efficiency of centrifugal compressors,were implemented in FORTRAN code and then were compared with experimental results in order to establish a loss correlation set to determine,with good approximation,the isentropic efficiency of single stage compressor.The aim of this study is to provide a suitable loss correlation set for determining the isentropic efficiency of a single stage centrifugal compressor,because,with a large amount of loss mechanisms and correlations available in the literature,it is difficult to ascertain how many and which correlations to employ for the correct prediction of the efficiency in the preliminary stage design of a centrifugal compressor.As a result of this study,a set of correlations composed by nine loss mechanisms for single stage centrifugal compressors,conformed by a rotor and a diffuser,are specified. 相似文献
718.
Sobolevsky N. M. Latysheva L. N. Kuznetsov H. V. Panasyuk M. I. Podzolko M. V. 《Cosmic Research》2021,59(4):259-267
Cosmic Research - A special version of the SHIELD transport code has been developed intended for radiation protection purposes in space. The calculation of the fluxes of primary and secondary... 相似文献
719.
Cosmic Research - We have analyzed the experimental data obtained in 2016–2019 from the measurements of plasma disturbances and electric currents induced at ionospheric altitudes upon the... 相似文献
720.
N. S. Dushin N. I. Mikheev I. M. Gazizov I. A. Davletshin 《Russian Aeronautics (Iz VUZ)》2017,60(4):583-590
A technique that allows simultaneous heating of the heat-exchange surface and estimation of its local temperature from the corresponding electrical resistance of the heating element is presented. The systematic error in measurements of the local heat transfer coefficient has been analyzed. A relation that takes possible heat loss into account and minimizes the measurement errors has been obtained. 相似文献