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Information × Registration Number 0221U100516, 0118U003442 , R & D reports Title Investigation of applied issues of application of supercavitating, jet and unseparated flows for high-speed underwater motion popup.stage_title Head Savchenko Yurii M., Доктор технічних наук Registration Date 06-01-2021 Organization Institute of Hydromechanics of NAS of Ukraine popup.description2 A series of studies on the disk entry into the water at small angles of inclination of the trajectory to the free surface was continued. The experimental setup was modernized, stroboscopic illumination on LEDs with a frequency of up to 1000 frames per second was completed and recording equipment was improved. Work was carried out to modernize the pool to increase the depth to 500 mm and length to 2000 mm, as well as catapults to expand the range of angles of entry of the model into the water. The test results are presented and analyzed. Experimental studies of the previously proposed body of revolution V with a very short zone of pressure increase were conducted. The use of a wind tunnel at the Technical University of Braunschweig (Germany) has reduced the influence of flow boundaries and increased the Reynolds number. Measurement of static pressure and visualization of the flow using the oil flow on the surface of the model showed the presence of separation on a smooth body. It was partially eliminated due to the use of thin obstacle rings. The obtained experimental pressure distributions deviate significantly from the theoretical one. A completely nonlinear solution of the problem of a heavy liquid flow around a submerged body with a free surface is presented in the form of analytical expressions for the complex potential, complex velocity and reflection function. These functions explicitly contain the magnitude of the velocity on the free surface and the direction of velocity on the surface of the body as a function of a variable parameter. They are determined from a system of integral equations and solved numerically using the developed iterative method. For the weightless flow, the coefficient of lift decreases as the cylinder approaches the free surface. The shape of the free surface significantly depends on the circulation, and at a certain value on the depth of immersion.  Product Description popup.authors Ivanyuk Volodymyr F. Vlasenko Yurij D. Kashirikhin Leonid P. Kyselyov Taras P. Kozenko Oleg M. Manova Zinaida I. Naumova Olena I. Nesteruk Ihor G Savchenko Georgii Yu. Savchenko Yurii M. Semenenko Volodymyr M. Semenov Yurii A. Chychyk Petro D. popup.nrat_date 2021-03-17 Close