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Information × Registration Number 0206U005730, 0101U001838 , R & D reports Title Study of dynamics of hydromechanical objects with cavitating elements as multidimensional non-linear non-steady systems popup.stage_title Head Pilipenko Victor Vasilyevich, Registration Date 11-05-2006 Organization Institute of Technical Mechanics NASU and NSAU popup.description2 Methodic fundamentals and software for the numerical simulation of unsteady 3-D turbulent gas flows through vane-type engines are developed using the time-explicit differential scheme of an increased order of accuracy. Based on the finite-element method, a new approach to the numerical simulation of unsteady 2-D flows of a compressible fluid in the complex-form region is proposed. Theoretical and experimental approaches to the research in high-frequency high-amplitude cavitation oscillations of fluid pressure through hydraulic systems integrating local resistances are developed. From the Navier-Stokes equations and the barotropic equation of the state of a steam and fluid medium, an unsteady axisymmetrical cavitation flow through convergent-divergent channels of local resistances of hydraulic systems are modeled mathematically. Experimental studies of high-frequency oscillation of the fluid through the hydraulic systems with local resistances are made in a significantly extended range of variations inpressures at the resistance inlet. Studies in asymmetrical conditions of the cavitation flow through inducer-type prepums of liquid propulsion are conducted using the model of the cavitation flow where a cavity is closed by the turbulent wake. For the first time backgrounding of the physical mechanism of initiation of an asymmetrical cavitation flow around vanes is presented. Parameters for the dynamics of 2D cavitating inducer-type centrifugical pumps of various designs, standard dimensions and capacity are determined by experiments and calculations. From the results obtained, a mathematical model of the dynamics of the cruise engine of the third stage of an advanced multistage launch vehicle is built, and the stability of the pump systems of the above rocket feedline in regard to cavitation oscillation is studied. A new approach to the mathematical modeling longitudinal vibrations of liquid LVs, based on the finite-element model of natural longitudinal structural oscillation in mathematical modeling the dynamics of the system "Liquid propulsion system - LV's body " is proposed. The model takes into account dissipative connections between structural elements and dynamical interaction of these elements between them and with subsystems of the liquid propulsion system of the first stage. The approach proposed allowed refining understanding of the heart of the phenomenon of longitudinal instability of liquid LVs and extending backgrounding of the dynamical coupling the structural body and the liquid propulsion system. Using the finite-element method, free oscillations of the LV space stage are modeled mathematically as a complicated 3-D hydromechanical system with cavities containing the fluid. An approach to the determination of the dynamic response of space stage having a complicated 3-D configuration of propellant tanks under LV longitudinal instability conditions is proposed. A dynamic compatibility of the cruise engine and the structure of the space stage body of liquid LV is analyzed. The mathematical models proposed, software and methodical support, the research results will be employed by factories of Ukraine's aircraft and rocket-space industries. Product Description popup.authors popup.nrat_date 2020-04-02 Close