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Information × Registration Number 0220U100819, 0118U005413 , R & D reports Title The Estimation of the acoustic features by sound flap, given birth by detachable currents and supersonic flow. popup.stage_title Head Grinchenko Viktor T., Доктор фізико-математичних наук Registration Date 28-01-2020 Organization Institute of Hydromechanics of NAS of Ukraine popup.description2 The report presents the results obtained during the current phase of the NTR implementation. The thesis about the importance of the problem of estimating the starting noise levels of rockets is formulated and the possible ways of solving it are outlined. Semi-empirical modeling using experimental data on the acoustic properties of supersonic jet jets was chosen as the basic approach for the research. An advanced semi-empirical technique for estimating acoustic loads on the main part of a rocket during take-off from a launch complex with a closed-type pipeline has been developed based on the solution of the boundary-value problem of sound propagation in the environment. The basic novelty of the proposed model is to use a priori hypotheses about the nature of the phase properties of the elementary sources that form the acoustic field of the jet. The contribution to the total sound field of radiation from the inlet and outlet openings of the pipeline is estimated. It is shown that from the practical point of view, the influence of the part of the jet which did not leave the duct can be neglected. The calculation procedure was verified when comparing the estimated estimates and full-scale data on the real launches of space missiles. Possible reasons for the significant variability of acoustic data from different launches of the same missile are indicated. Product Description popup.authors Vovk Igor V. Grinchenko Viktor T. Malyuga Volodymyr S. Oliynyk Valery N. Ostroverkh Borys Savitsky Oleg popup.nrat_date 2020-04-02 Close