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Information × Registration Number 0224U000347, 0122U000800 , R & D reports Title Investigation of hydrodynamics and stability of unsteady motion of bodies when crossing the free boundary of liquid in the regimes of supercavitation and unsepatated flow popup.stage_title Head Savchenko Yurii M., д.т.н. Registration Date 05-01-2024 Organization The Institute of Hydromechanics of the National Academy of Sciences of Ukraine popup.description2 A method for researching the underwater launch of models and the exit of supercavitating models from the water was developed. It does not require a catapult to accelerate the models. An installation for researching the vertical exit from water of ventilated models with large-diameter disk cavitators was mounted. High-speed video-recording the cavity formation and evolution was tested. Computer simulation of cavity formation during vertical motion and exit of supercavitating models from water was performed. It showed satisfactory correspondence with experimental data. A method and programs for computer simulation of ventilated cavity evolution behind a disk cavitator during horizontal acceleration of a model near free water surface from low initial velocities were developed. Comparison with experimental data showed that the accepted mathematical model correctly describes main features of hydrodynamic processes during acceleration of ventilated models. A problem of steady flow of incompressible fluid around elongated bodies of revolution having a special continuous shape moving horizontally near free surface was solved. Calculation of the pressure on a surface of a slender elongated body of revolution during motion along the symmetry axis near the free water surface were made. It was shown that bodies with a sharp concave nose don’t have braking point and have increased pressure values. This reduces vertical velocities on the water surface and wave drag. A boundary value problem about impact of a body fully submerged in an open container filled ideal incompressible liquid was solved. The streamline pattern, velocity distribution on a free surface and pressure impulse along the body and container were determined for different shapes of the cross-section of the cylindrical body in containers with a rectangular and semicircular cross-section. It was shown that the pressure impulse and added mass increase as the body approaches the container bottom or side walls. Product Description popup.authors Ivanyuk Volodymyr F. Vlasenko Yurij D. Kozenko Oleg M. Manova Zinaida I. Naumova Olena I. Nesteruk Ihor G Savchenko Georgii Yu. Savchenko Yurii M. Semenenko Volodymyr M. Semenov Yuriy A. Temerov Anatoliy S. popup.nrat_date 2024-01-05 Close