In 1988, with direct financial support from Energia Research and Production Association and Yuzhnoye Design Office, a vacuum aerodynamic cryogenic-pumping plant (VAU-2M) was put into operation at the department. In performance, the plant compares well with the best foreign closed-circuit plants operating on a refrigeration cycle.<\/p>\n\n\n\n Plant layout<\/strong><\/p>\n\n\n\n Using the plant, a number of new results have been obtained on:<\/strong><\/p>\n\n\n\n These results made it possible to conduct full-scale aerodynamic experiments using PION passive reference satellites.<\/p>\n\n\n\n A space experiment called \u00abVariation\u00bb was conducted together with Central Special Design Office, Nauka Scientific and Technical Center (Samara, Russia), and Kosmos Research Institute and Computing Center (Moscow). Two spherical satellites of much the same size (diameter about 0.3 m) and mass (about 45 to 50 kg), but coated with different structural materials [AMG-6 alloy, glass fabric (Si), and nitroenamel (AKA-12)] were injected into the same orbit at a time. The use of existing space control equipment for obtaining information on the orbital period variation \u0394T of the satellites made it possible to eliminate the atmospheric density from the information being processed and determine the ratio Cxi\/Cxj of their drag coefficients.<\/p>\n\n\n\n The results of the full-scale and laboratory experiments are given in the table.<\/p>\n\n\n\n The calibration values of the drag coefficients of models of the PION satellites had been measured in the VAU-2M vacuum aerodynamic plant before their launch. A qualitative and quantitative agreement between the results of the laboratory and full-scale experiments made it possible to conclude that the simulation of the physical features of interaction of high-velocity rarefied gas flows with the basic structural materials of satellite coatings in the VAU-2M plant followed by transferring them to actual flight conditions is sufficiently adequate.<\/p>\n\n\n\n![\"\"\/](\"http:\/\/itm.dp.ua\/wp-content\/uploads\/2023\/05\/EXBA_16_0.jpg\")
Basic parameters of the plant<\/strong><\/p>\n\n\n\n \u2116
\u043f\/\u043f <\/td> Prameter <\/td> Measure <\/td> Quantity value <\/td><\/tr> 1 <\/td> Working chamber volume <\/td> \u2003m3<\/sup> <\/td> \u20033.0<\/td><\/tr> 2 <\/td> Source chamber volume <\/td> \u2003m3<\/sup> <\/td> \u20030.5<\/td><\/tr> 3 <\/td> Working chamber pressure <\/td> \u2003Torr <\/td> \u20035\u202210-6<\/sup>…5\u202210-5<\/sup><\/td><\/tr> 4 <\/td> Source chamber pressure <\/td> \u2003Torr <\/td> \u20035\u202210-5<\/sup>…5\u202210-4<\/sup><\/td><\/tr> 5 <\/td> Working chamber pumping speed <\/td> \u2003l\u2022\u0441-1<\/sup> <\/td> \u20038\u202210-3<\/sup><\/td><\/tr> 6 <\/td> Source chamber pumping speed <\/td> \u2003l\u2022\u0441-1<\/sup> <\/td> \u20036\u202210-3<\/sup><\/td><\/tr> 7 <\/td> Mass-average flow velocity <\/td> \u2003m\u2022\u0441-1<\/sup> <\/td> \u20034\u202210-3<\/sup>…8\u202210-3<\/sup><\/td><\/tr> 8 <\/td> Flow ionization degree <\/td> \u2003deg <\/td> \u200310-2<\/sup> … 10-6<\/sup><\/td><\/tr> 9 <\/td> Flow divergence angle <\/td> \u2003deg. <\/td> \u2003<=3<\/td><\/tr> 10 <\/td> Working chamber core diameter <\/td> \u2003mm <\/td> \u20030.1<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n ![\"\"\/](\"http:\/\/itm.dp.ua\/wp-content\/uploads\/2023\/05\/Otd16_5.jpg\")
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![\"\"\/](\"http:\/\/itm.dp.ua\/wp-content\/uploads\/2023\/05\/Otd16_6.jpg\")
<\/figure>\n\n\n\n Data source <\/td> CX1<\/sub> \/ CX2<\/sub> <\/td> \u2003CX3<\/sub> \/ CX4<\/sub> <\/td> \u2003CX6<\/sub> \/ CX5<\/sub><\/td><\/tr> Laboratory simulation <\/td> 1.045 <\/td> \u20030.957 <\/td> \u20031.042<\/td><\/tr> Full-scale experiment <\/td> 1.039 <\/td> \u20030.984 <\/td> \u20031.035<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n