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851.
We consider a probabilistic estimation of microaccelerations being produced in the inboard environment of an orbital laboratory as a random process; based on this estimation we analyzed a probability of fulfilling the favorable conditions to realize gravity-sensitive processes. The approach suggested can be applied when designing a space laboratory to meet the requirements for the microaccelerations inside the working zone of technological equipment. 相似文献
852.
The solution is constructed based on using the general theory of physically orthotropic shells generalizing the Vlasov equations. The numerical results demonstrating the orthotropy influence on the stress strain state are presented. 相似文献
853.
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
854.
We review the present theoretical and numerical understanding of magnetic field amplification in cosmic large-scale structure, on length scales of galaxy clusters and beyond. Structure formation drives compression and turbulence, which amplify tiny magnetic seed fields to the microGauss values that are observed in the intracluster medium. This process is intimately connected to the properties of turbulence and the microphysics of the intra-cluster medium. Additional roles are played by merger induced shocks that sweep through the intra-cluster medium and motions induced by sloshing cool cores. The accurate simulation of magnetic field amplification in clusters still poses a serious challenge for simulations of cosmological structure formation. We review the current literature on cosmological simulations that include magnetic fields and outline theoretical as well as numerical challenges. 相似文献
855.
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857.
A. Chilingarian V. Babayan T. Karapetyan B. Mailyan B. Sargsyan M. Zazyan 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(10):2680-2696
The Space Environment Viewing and Analysis Network (SEVAN) aims to improve the fundamental research on particle acceleration in the vicinity of the sun, on space weather effects and on high-energy physics in the atmosphere and lightning initiation. This new type of a particle detector setup simultaneously measures fluxes of most species of secondary cosmic rays, thus being a powerful integrated device for exploration of solar modulation effects and electron acceleration in the thunderstorm atmosphere. The SEVAN modules are operating at the Aragats Space Environmental Center (ASEC) in Armenia, in Croatia, Bulgaria, Slovakia, the Czech Republic (from 2017) and in India. In this paper, we present the most interesting results of the SEVAN network operation during the last decade. We present this review on the occasion of the 10th anniversary of the International Heliophysical Year in 2007. 相似文献
858.
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
859.
A. A. Ryabov V. I. Romanov V. N. Rechkin Yu. N. Shmotin A. V. Veselov 《Russian Aeronautics (Iz VUZ)》2011,54(4):379-386
A computational technique, developed for analysis of strength, stability and low-cycle durability of GTE exhaust frame complex
structure under operational and emergency loads is described. The presented technique, based on the ANSYS and STAR-CD engineering
analysis software, and self-design software can improve the accuracy and efficiency of calculations, and reduce efforts on
finite element mesh development, performing calculations and processing of results. 相似文献
860.
The stress-strain state of thin-walled aircraft structures such as a wing or fuselage made of composite materials is determined
based on the beam theory. The laminated skin is orthotropic. The solution was obtained without using the centroidal principal
section axes and subdividing the problem in shear and torsion. A calculation variant with skin discretization along the section
contour was studied. 相似文献