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Information × Registration Number 0222U000534, 0120U101147 , R & D reports Title Controlling the ejecting property of a pulsed supersonic annular jet in variable backpressure conditions popup.stage_title Head Voropaiev Hennadii О., д.ф.-м.н. Registration Date 12-01-2022 Organization The Institute of Hydromechanics of the National Academy of Sciences of Ukraine popup.description2 Formation of near-wall supersonic jet and its influence on the ejection process and ejected gas mass flow rate are studied depending on the high pressure applied to the oblique nozzle on the outer wall of the axisymmetric ejector mixing chamber. Causes and conditions for the supersonic jet instability in the initial section of the ejector are determined, as well as impact on the ejector efficiency and formation of a stable shock wave in the mixing chamber. For the case of an ejector operating with a connected cylindrical container with both fixed and variable volume, simulating an unfolding airbag, the effects of the increasing back pressure are studied on the formation and behavior of the supersonic jet, the ejector efficiency over time and the average pressure drop in the container during the unfolding process. Calculations and analysis of gas-dynamic processes during gas leakage from the gas generator into the ejector prechamber were continued in order to determine its parameters which ensure stable operation of the supersonic annular nozzle at inlet pressure, 35 ÷ 45 bar, and ejecting gas mass flow rate, 0.5 ÷ 0.6 kg/s. Influence of a change in volume of the prechamber and gas generator hole profiling on high pressure throttling, as well as unsteady structure of shock waves in the prechamber are studied. Self-similarity of gas-dynamic processes in the ejector prechamber is shown relative to variable instantaneous values of parameters in the gas generator. The experimental techniques, the information-measuring complex and the special stand were improved to study the unsteady fields of static and total pressure in limited volumes at impulse supersonic flow with a given intensity, as well as to determine experimentally its ejecting capacity limits under the conditions of increasing back pressure. The obtained experimental data are in a good agreement with the calculated ones both in terms of airbag filling and ejection coefficient, and frequency characteristics. Product Description popup.authors Vynograds'kyj Pavlo M. Dymytriieva Nataliia F Zagumennyi Iaroslav Viktorovich Korobov Vitalii I. Paramonov Yuriy О. Rozumnyuk Natalia V. Sirosh Olena O. Shkvar Yevgenii O. Yurchenko Nina F. popup.nrat_date 2022-03-09 Close