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451.
  总被引:3,自引:0,他引:3  
This paper analyzes the state of the ionosphere during two geomagnetic storms of a different intensity evolving in different sectors of local time in different seasons. There were used the data from a network of ionospheric stations located in the opposite longitudinal sectors of 80°-150° E and 250°-310° E.This analysis has permitted us to conclude that the detected differences in the variations of the disturbances are likely to be determined by the local time difference of the geomagnetic storm development, its intensity and by the different illumination conditions of the ionosphere.  相似文献   
452.
Problems arising in introduction of gasodynamic seals in aircraft engines are considered. The operation of a face gasodynamic seal as part of a natural gas pump is analyzed and its efficiency in the presence of oil is shown.  相似文献   
453.
The test results of a conventional combustion chamber with the improved structure are presented. The concentration of toxic substance emissions is reduced as compared with combustion chambers of the similar type.  相似文献   
454.
The paper describes a device and a technique of forming the information processing algorithms used in the integrated acoustic monitoring system for jet fuel tanks, intended for monitoring the level, density and mass of liquid products.  相似文献   
455.
A technique for linear interpolation of the multidimensional characteristics of a coaxial propeller fan with opposite rotation propellers is proposed; the technique makes it possible to simulate the turbofan engine operation in the entire range of flight conditions and reduce expenses for fullscale tests. The mathematical models obtained meet the requirements imposed in the semi-full-scale simulation.  相似文献   
456.
The problem of determining the “potential” number of integration steps by explicit difference schemes is solved within the framework of the prediction model for chemically non-equilibrium processes.  相似文献   
457.
    
In this paper, we examine experimentally some devices the principle of action of which is based on using the dynamic pressure of air extracted to engine cooling and which are meant for reducing the radial temperature gradient in GTE rotor disks. We established that the devices equipped with the ejector channels make it possible to accelerate the process of the disk hub heating by hot air suction from the cavity periphery towards the rotor axis of rotation. Using the data of visualization studies, we show the possibility for efficient operation of ejector devices in the conditions of real GTE rotor circumferential velocities.  相似文献   
458.
The paper highlights significance of the interturbine transition duct as part of the high pressure and low pressure turbine spool. The correlations have been suggested allowing us to estimate variation of the average cross section flow swirl while its passing the interturbine transition duct.  相似文献   
459.
    
The finite-difference method acceptable for on-board computers is applied to analyze the thermo-stressed state for the thermal-barrier coating of a perforated turbine blade and its wall at transient and stationary conditions of air-breathing jet engine operation during a flight.  相似文献   
460.
A new derivation of the GYROLITE stability criterion is presented. It is confirmed that, for the satellite to have a stable attitude, the spinning part must have a favorable inertia ratio.  相似文献   
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