排序方式: 共有275条查询结果,搜索用时 31 毫秒
41.
I. S. Akhmed’yanov 《Russian Aeronautics (Iz VUZ)》2010,53(2):230-234
To complete study [1], the procedure of applying the numerical quadrature method to analyzing the shells of revolution under
axisymmetrical loading is presented. 相似文献
42.
In this paper, a process of flanging to create thin-walled axisymmetrical shells with the shape of truncated cone is analyzed. Also presented are some dependences that make it possible to determine the relative depth of a formed piece at the given piece-blank thickness ratio. 相似文献
43.
In this paper, the results of an experimental study concerning average heat transfer in an annular channel with flow swirling
by an endless screw and spherical grooves on the convex surface are presented. Also analyzed is the heat and hydraulic efficiency
of grooves application under conditions being considered. 相似文献
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45.
Hardware-in-the-loop testing technology for automatic control, condition monitoring and diagnostics systems of gas turbine engines is described. The technology proposed makes it possible to simulate combinations and chains of unexpected and gradual failures of engines, transducers and actuators. 相似文献
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47.
G. P. Anshakov A. I. Belousov A. V. Sedel’nikov A. S. Gorozhankina 《Russian Aeronautics (Iz VUZ)》2018,61(3):347-354
The influence of various control systems of the orbital motion of a technological spacecraft on the level of microacceleration of its internal environment is simulated. Conclusions are drawn about the effectiveness of control systems with different actuators for realization of certain gravitationally sensitive processes onboard a spacecraft. 相似文献
48.
David P. O’Brien Andre Izidoro Seth A. Jacobson Sean N. Raymond David C. Rubie 《Space Science Reviews》2018,214(1):47
The planetary building blocks that formed in the terrestrial planet region were likely very dry, yet water is comparatively abundant on Earth. Here we review the various mechanisms proposed for the origin of water on the terrestrial planets. Various in-situ mechanisms have been suggested, which allow for the incorporation of water into the local planetesimals in the terrestrial planet region or into the planets themselves from local sources, although all of those mechanisms have difficulties. Comets have also been proposed as a source, although there may be problems fitting isotopic constraints, and the delivery efficiency is very low, such that it may be difficult to deliver even a single Earth ocean of water this way. The most promising route for water delivery is the accretion of material from beyond the snow line, similar to carbonaceous chondrites, that is scattered into the terrestrial planet region as the planets are growing. Two main scenarios are discussed in detail. First is the classical scenario in which the giant planets begin roughly in their final locations and the disk of planetesimals and embryos in the terrestrial planet region extends all the way into the outer asteroid belt region. Second is the Grand Tack scenario, where early inward and outward migration of the giant planets implants material from beyond the snow line into the asteroid belt and terrestrial planet region, where it can be accreted by the growing planets. Sufficient water is delivered to the terrestrial planets in both scenarios. While the Grand Tack scenario provides a better fit to most constraints, namely the small mass of Mars, planets may form too fast in the nominal case discussed here. This discrepancy may be reduced as a wider range of initial conditions is explored. Finally, we discuss several more recent models that may have important implications for water delivery to the terrestrial planets. 相似文献
49.
S.?N.?Grigor’ev V.?A.?DolgovEmail author A.?V.?Krasnov A.?A.?Kabanov N.?S.?Andreev 《Russian Aeronautics (Iz VUZ)》2015,58(2):244-250
A method of technologic audit for technical re-equipment of enterprises is considered. The method developed is intended to verify technological solutions of projects of technical re-equipment of enterprises according to indicators of productivity. 相似文献
50.
V.?A.?Afanas’ev G.?L.?Degtyarev A.?S.?MeshchanovEmail author 《Russian Aeronautics (Iz VUZ)》2018,61(1):23-31
Real values of parameters for a space vehicle and its steering devices are specified by using the motion parameters measured in flight based on solving the differential equations of motion. 相似文献