RESEARCH DEPARTMENT OF TECHNICAL HYDROMECHANICS

     FROM THE HISTORY OF DEPARTMENT

     The Department was established in 1965. It is the successor of the Departments of Vessel Hydrodynamics (headed by Academician of Academy of Sciences of Ukrainian SSR G. Pavlenko) and High Speed Hydrodynamics (headed by Doctor of Technical Sciences A. N. Panchenkov). From 1965 to 1972, it was directed by Candidate of Technical Sciences M. M. Didkovskiy, from 1972 to 1979 - by Corresponding Member of NASU A. Ya. Oleynik, from 1979 to 2004 - by Doctor of Physical and Mathematical Sciences M. V. Saltanov. Since 2004, the department is managed by a Corresponding Member of NASU V. I. Nikishov. Currently, it is staffed by one Doctor and five Candidates of Sciences.

     RESEARCH ACTIVITIES AND ACHIEVEMENTS

     Various problems of fluid mechanics are theoretically and experimentally studied in the Department. Most of the experiments were carried out using the large-scale faciliteies of the Institute, i.e., the experimental tank and hydraulic trays. In addition, the Department has a small laboratory with a circular tank designed for experimental studying of characteristics of longitudinal vortices (the Görtler vortices).

     The methods for the numerical simulation of fluid flows are developed in the Department for the cases when bodies interact with the bodies or limited surfaces. The latter ones are treated as solid walls of any configuration and deformable surfaces (in particular, the water-air interface). A new method for solving of two-dimensional Navier-Stokes equations in multiply connected domains is developed that uses the vorticity transport equations in the main flow region. An adaptability of this approach allows for more effective and accurate solution of the problems at high Reynolds numbers. On the based on thi technique, we examined the flow regime in a system of bodies arranged in parallel and in series, developed the new schemes for reduction of hydrodynamic drag of bluff bodies.

     A numerical algorithm for simulation of unsteady hydraulic flows is developed. On its basis, the hydrodynamic characteristics of a specified area of the Dnipro River near Kyiv are calculated and the resulting estimates str obtained for current velocities and water level rise in high water depending on the bottom profile and its deformation. A special tray for modeling of sediment transport and optical means for measuring of bottom scour are created.

     The mathematical models are developed for magnetic field generation by moving objects in a weakly conducting liquid. It is shown that the inductive magnetic field can be detected with modern magnetometers. A considerable attention is paid to studying of the nonlinear interaction processes of solitary surface waves with the coastal slopes and topographic irregularities of the bottom. Propagation and interaction of single large-amplitude internal waves with the topographic bottom and slope irregularities is also investigated.

     The Department investigates the fine structural features of turbulent fields of scalar additives. We study the formation features of fluctuation spectrum of an optical refractive index due to fluctuations in temperature and salinity and develop the models for its description. The statistical characteristics of the light wave propagating in the sea are analyzed.

     The researches of a stratified fluid motion under the influence of centrifugal and electromagnetic forces are carried out. The asymptotic relations for description of the individual modes are introduced. Based on these investigations, we have proposed the classification diagrams of types of motion.

     APPLIED ACTIVITIES

     The Department staff is involved in the implementation of large industrial and contract projects, notably the construction of the rail-road bridge on the Dnipro river in Kyiv, construction of a bridge over the river Amu Darya, creation and operation of the channel in the Danube Delta.