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181.
A technique of analyzing the flutter initiation in flat plate compressor cascades was developed. The viscous and inviscid flow study was carried out using the COBRA solver based on the modified implicit Godunov method and unsteady implicit method updated for using. The flutter conditions were revealed and the effect of taking into account viscosity, angles of attack and time steps was investigated.  相似文献   
182.
The influence of the clearance between the case and blade ends of the semi-open impeller on the centrifugal stage characteristics is considered using the experimental data and numerical calculation results.  相似文献   
183.
The influence of geometry and operating conditions of the centrifugal compressor stage on the radial gas force is determined on the basis of the theoretical method and calculation program using experimental boundary conditions.  相似文献   
184.
The application of the low dissipative high-order accurate scheme for numerical solution of the Euler and Navier-Stokes equations in the two-dimensional statement is considered. The scheme of calculating space derivatives is the seven-point central-difference approximation of the fourth order with the coefficients optimized to reduce the dispersion errors. The optimized six-step Runge-Kutta method is used for evaluating the time derivatives. By means of filtration, spurious pulsations are suppressed and shocks are processed. The results of verifying the calculation scheme realized on the stationary problem of flow around the model turbine blades are presented.  相似文献   
185.
A mathematical model of the process of bending and rolling the thin-walled components is presented taking into account the geometrical nonlinearity. Also presented is the technique for calculating the setup variables of bending equipment, which is based on reduction of the initial differential boundary-value problem to the discrete one with the use of the finite difference method.  相似文献   
186.
The paper presents a technique of forming and evaluating the allowable clearance between a launch vehicle fairing and spacecraft.  相似文献   
187.
This paper deals with the technical features of designing an information-controlling system to prevent critical operating conditions of the helicopter flight, a technique for evaluating its effectiveness, analysis and synthesis of the measurement channels, forming of warning signals, and information support of the crew in abnormal situations.  相似文献   
188.
We highlight how the downward revision in the distance to the star cluster associated with SGR 1806–20 by Bibby et al. (2008) reconciles the apparent low contamination of BATSE short GRBs by intense flares from extragalactic magnetars without recourse to modifying the frequency of one such flare per 30 years per Milky Way galaxy. We also discuss the variety in progenitor initial masses of magnetars based upon cluster ages, ranging from ∼50 M for SGR 1806–20 and AXP CXOU J164710.2–455216 in Westerlund 1 to ∼17 M for SGR 1900+14 according to Davies et al. (2009) and presumably also 1E 1841–045 if it originated from one of the massive RSG clusters #2 or #3.  相似文献   
189.
We determine the behavior of onboard gas-generator flowrate for generating the cavitation flow around a hybrid aerial underwater vehicle by using an annular wing on the underwater trajectory section.  相似文献   
190.
Junocam is a wide-angle camera designed to capture the unique polar perspective of Jupiter offered by Juno’s polar orbit. Junocam’s four-color images include the best spatial resolution ever acquired of Jupiter’s cloudtops. Junocam will look for convective clouds and lightning in thunderstorms and derive the heights of the clouds. Junocam will support Juno’s radiometer experiment by identifying any unusual atmospheric conditions such as hotspots. Junocam is on the spacecraft explicitly to reach out to the public and share the excitement of space exploration. The public is an essential part of our virtual team: amateur astronomers will supply ground-based images for use in planning, the public will weigh in on which images to acquire, and the amateur image processing community will help process the data.  相似文献   
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