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961.
刀具角度分析与计算的矢量方法 总被引:3,自引:0,他引:3
刀具技术是机械制造工业的基础与支柱,刀具角度的分析与计算是刀具技术中关键技术问题之一。提出分析与计算刀具角度的矢量方法,概述矢量基本知识,阐述刀具角度的矢量法基本原理及其应用,以适应刀具技术发展之需要。 相似文献
962.
Yu.?E.?Sedel’nikovEmail author D.?A.?Veden’kin V.?E.?Latyshev D.?V.?Nikishina D.?S.?Gushchina 《Russian Aeronautics (Iz VUZ)》2015,58(2):221-226
The paper deals with the problem of creating airborne antenna systems for advanced unmanned aerial vehicles (UAVs). The ways of solving the basic problems, based on a combination of empirical approaches, electrodynamic simulation, and experimental results are proposed. 相似文献
963.
L.?V.?GorunovEmail author V.?V.?Takmovtsev E.?V.?Sokolov D.?V.?Ryabinin A.?V.?Il’inkov 《Russian Aeronautics (Iz VUZ)》2015,58(2):233-236
An experimental pressure field in operating clearance and flowrate parameters analysis for different eccentricities, inlet oil pressures, and journal rotating velocities are presented for a radial multilobe journal bearing. Lubricating film breakdown zones in bearing oil ducts caused by complicated construction and journal rotation are observed. 相似文献
964.
We present the results of an experimental study of deflections for the loaded plates that are discretely connected to a circular cylindrical shell along the generatrix lines. The influence of structure element connection elasticity on these deflections has been examined. The unique experimental setup and three specimens being tested are described. Satisfactory agreement is shown between the experimental results and the calculation data obtained by the simplified mechanical model of a plane problem. 相似文献
965.
V. A. Afanas’ev G. L. Degtyarev A. S. Meshchanov T. K. Sirazetdinov 《Russian Aeronautics (Iz VUZ)》2013,56(1):99-106
We obtained an on-off control law for two spacecraft (SC) rocket engines creating the angular acceleration in the opposite directions considering that SC is controlled by the rocket engines with an exponential increase of thrust at starting and decrease at shutdown. This control law provides the change-over of SC from the initial angular position to the final one in the scheduled time. A special trajectory consisting of eight typical segments is proposed to identify the angular acceleration and delay of its formation in the rocket engines. Both problems are solved by the method of analytical construction of composite trajectories for the angular turn from the typical segments on which the differential equations of angular motion have analytical solutions. The results are applicable for the development of promising space interceptors and design of onboard control systems. 相似文献
966.
B. A. Antuf’ev 《Russian Aeronautics (Iz VUZ)》2012,55(1):91-94
An approximate solution of the divergence problem, that is, of the static instability of a plate discretely supported by a system of stiffening ribs (stringers) in the gas flow. The critical velocity of divergence is determined in one-term approximation and the influence of stringers on it is analyzed. 相似文献
967.
Using the method of quasisolutions for inverse boundary-value problems of aerohydrodynamics, a problem of constructing an airfoil was solved by the specified velocity distribution along the sought airfoil contour when there is an irregularity in the flow such as a vorticity source. The cases of a source (sink) and vortex are obtained as particular ones. The airfoils are constructed numerically and analytically and conclusions are made about an influence of the irregularity position and type on the shape and aerodynamic characteristics of the airfoil. 相似文献
968.
Editorial Office of Chinese Journal of Aeronautics 《中国航空学报》2011,24(2):235
About Journal Chinese Journal of Aeronautics (CJA) is a comprehensive academic journal dealing with the fields of aeronautics and astronautics. It reports researches concerning the two fields in China and abroad to promote the academic 相似文献
969.
970.
A problem on chaotic vibrations of the Bernoulli-Euler beams is formulated. The wavelet transform was first applied to investigate
the complex beam vibrations. The validity of results was provided by using two methods of solution, namely, the finite element
method and finite difference method. 相似文献