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991.
E. S. Soldatkina 《Russian Aeronautics (Iz VUZ)》2013,56(3):291-296
Application prospects, a functional diagram and algorithms for processing informative signals from a vortex aerodynamic angle and true airspeed sensor are considered. The requirements for transducers of pressure pulsations downstream of vortex generators are formed, a technique and connection of these transducers to the sensor circuit diagram are described. A technique is presented to analyze individual and resultant errors of the aerodynamic angle and true airspeed channels. 相似文献
992.
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
993.
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
994.
995.
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
996.
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
997.
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
998.
Based on the experimental data, a dependence of the minimal friction losses in cascades was obtained. A turbine stage efficiency
gain as a result of cascade improvement over the last three decades of the 20th century was estimated by this dependence. 相似文献
999.
Hassanali Akbari Asti Bhatt Cesar La Hoz Joshua L. Semeter 《Space Science Reviews》2017,212(1-2):249-294
Space plasmas are host to the electrostatic Langmuir waves and a rich range of processes associated with them. Many of such processes that are of interest in micro-scale plasma physics and magnetosphere-ionosphere physics are open to investigation via incoherent scatter plasma lines—i.e., a pair of resonant peaks in the incoherent scatter radar (ISR) spectrum, symmetrically displaced from the radar transmitting frequency by about the plasma frequency, as the signature of Langmuir waves in the ISR spectrum. There now exists a large body of literature devoted to the investigation of a number of topics in ionospheric physics via plasma line theory and observation. It is the goal of this work to provide a comprehensive review of this literature, from the early theoretical works on oscillations in magnetized plasma to the recent advances in plasma line measurements and applications. This review includes detailed theoretical discussions on the intensity and frequency displacement of plasma lines. It reviews the experimental observations of plasma lines enhanced by various sources of energy and discusses the implications of the observations in the context of ionospheric physics. The review also covers the practical aspects of plasma line measurements, from measurement techniques to the applications of plasma lines in estimating the bulk parameters of the ionosphere. 相似文献
1000.
S. A. Mikhailov L. V. Korotkov S. A. Alimov D. V. Nedel’ko 《Russian Aeronautics (Iz VUZ)》2011,54(3):247-253
A technique is suggested for calculating the helicopter spatial motion and the stress-strain state of a skid landing gear
in the course of landing with regard for the second landing impact; geometric, material and design nonlinearity of undercarriage
springs deformation is taken into account. The comparison between the analysis results and experimental data is presented. 相似文献