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1.
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   
2.
This paper presents the results of optical observations in the active space experiment “Radar-Progress” on April 17, 2013, after switching on the approach-correction engine of the Progress M-17M cargo spacecraft at thermospheric heights (412 km), are presented in this paper. During engine operation, a region of enhanced emission intensity has been recorded. It was presumably related to the scatter of twilight solar emission at the engine exhausts in the cargo spacecraft orbit and, probably to the occurrence of an additional emission in the atomic oxygen line [OI] 630 nm. The maximum observed dimensions of the emission region were ~350 and ~250 km along the orbit and across it, respectively. The velocity of the expansion of the emission region at the first moments after the initiation of engine operation was ~7 and ~3.5 km/s along the orbit and across it, respectively. The maximum intensity of the disturbed region is estimated to be a value equivalent to ~40–60 R within the spectral band of 2 nm. No optical manifestation, which would exceed the natural variations in brightness of the night airglow and which would be related to possible large-scale modification of the ionosphere, was detected in the natural emission lines [O] 557.7 and 630.0 nm in a zone remote from the place of injection of engine exhausts.  相似文献   
3.
A working process of a plasma spark plug is described and its improved structure that meets the requirements for start and operation stability limits is given. Also presented are the results of the plug tests under conditions of rarefaction to confirm its normal operation at the GTE altitude start.  相似文献   
4.
An algorithm for calculating the collision hazard factors for violating aircraft is given. The calculation results of the hazard factors in maneuvering to prevent dangerous approach and in its absence are compared.  相似文献   
5.
Uri JJ  Lebedev ON 《Acta Astronautica》2001,48(5-12):845-851
The Phase 1 research program was unprecedented in its scope and ambitious in its objectives. The National Aeronautics and Space Administration committed to conducting a multidisciplinary long-duration research program on a platform whose capabilities were not well known, not to mention belonging to another country. For the United States, it provided the first opportunity to conduct research in a long-duration space flight environment since the Skylab program in the 1970's. Multiple technical as well as cultural challenges were successfully overcome through the dedicated efforts of a relatively small cadre of individuals. The program developed processes to successfully plan, train for and execute research in a long-duration environment, with significant differences identified from short-duration space flight science operations. Between August 1994 and June 1998, thousands of kilograms of research hardware was prepared and launched to Mir, and thousands of kilograms of hardware and data products were returned to Earth. More than 150 Principal Investigators from eight countries were involved in the program in seven major research disciplines: Advanced Technology; Earth Sciences; Fundamental Biology; Human Life Sciences; International Space Station Risk Mitigation; Microgravity; and Space Sciences. Approximately 75 long-duration investigations were completed on Mir, with additional investigations performed on the Shuttle flights that docked with Mir. The flight phase included the participation of seven US astronauts and 20 Russian cosmonauts. The successful completion of the Phase 1 research program not only resulted in high quality science return but also in numerous lessons learned to make the ISS experience more productive. The cooperation developed during the program was instrumental in its success.  相似文献   
6.
The calculation made on the basis of simple mathematical models are presented for evaluating the temperature and thermal capacity of a plasma plug flame in the GTE afterburner in a wide range of startup conditions.  相似文献   
7.
Some results of investigating the geometrical and jet impact on secondary flows and thermal state of cooled inter-profile end surfaces of gas turbine engine nozzles have been set forth under different secondary flows interaction degree in a blade channel.  相似文献   
8.
We readily convince ourselves that most achievements can be credited to the construction of powerful jet engines, which enable a spaceship to escape gravity. The principle of jet propulsion seems to work perfectly; jet engines can accelerate a rocket up to an incredible speed of 11 km/sec. Looks like there is nothing left to desire. However, from the physical point of view, 11 km/sec is not such a large value compared, for instance, to the speed of light. Would it be possible to attain half of that speed using gas jets? Unfortunately, the answer is no. Nevertheless, that is not the end of the story. The purpose of this article is to show that it is still possible to use the same principle to remove limitations on attainable speed if instead of gas jets, we employ ultrafast electron beams. The basic idea of our construction was inspired by the paper by H. Morgan (ibid., vol. 13, pp. 5-10, 1998). In that article he experimentally refuted the common premise that nothing can go faster than light and gave some theoretical arguments supporting his experimental data. Although the nature and underlying principles of the Morgan phenomenon are yet to be understood, we can already start thinking of its practical applications  相似文献   
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