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Information × Registration Number 0224U001068, 0123U100820 , R & D reports Title Assessment of acoustic fields generated by various-scale vortex structures in the - and supersonic flows popup.stage_title Head Hrinchenko Viktor T., д.ф.-м.н. Registration Date 16-01-2024 Organization The Institute of Hydromechanics of the National Academy of Sciences of Ukraine popup.description2  Theoretical and quantitative modeling of the starting acoustic loads generated by a rocket with a controlled deviation of the thrust vector to compensate for the side wind in difficult weather conditions was carried out. The semi-empirical method of estimating acoustic loads from a supersonic jet of a rocket engine is adapted to the conditions of significant gas-dynamic interaction with launch structures outside the fire arm. For this, an original model of an additional sound source, formed on the launch table by the wake of a deflected jet, was developed. Considerable attention is paid to the critical analysis of the basic universal ratios embedded in the 4th acoustic model of a jet jet. In particular, instead of the traditional Eldred spatial distribution of acoustic energy, it uses the adjusted dependence obtained by Nagamatsu for the first time. A test calculation of the acoustic loads on the main part of the rocket was carried out when simulating the launch over an infinite gas extraction shaft. It is shown that even a slight exit of the jet trail outside the gas duct causes a sharp increase in the level of the generated sound. The contribution of the additional source formed by the deflected jet on the launch table determines the acoustic loads for the lift heights of the rocket up to two lengths of the laminar core of the free jet. As the rocket rises further, the impact of this effect quickly decreases and the acoustic loads approach the levels characteristic of free flight. Practical recommendations are given for reducing the impact of the launch acoustic loads on the rocket. Product Description popup.authors Basovsky Volodymyr G. Borysiuk Аndrii О. Vovk Ihor V. Gorodetskaya Natalya Sergeevna Grinchenko Viktor T Malyuga Volodymyr S. Oliinyk Valerii N. popup.nrat_date 2024-01-16 Close