Problems originated in modern hydrodynamics by traditional continuum models used under nonequilibrium conditions are considered in the paper. A new approach to the problems based on different joint branches of science is suggested. New generalized integral models include the structure evolution in open systems. The obtained solutions to some test problems and a number of the modern experimental data confirm the prospects in further development of the approach.

This paper presents an overview of the results of real-time numerical modeling of the sea hydrological fields in our country. The real-time modeling is the main alternative of using oceanographic data bases. The task of real-time modeling is formulated as an inverse problem, so, initial and boundary conditions are provided first of all. Sometimes it is possible to solve direct boundary task of real-time modeling of hydrological fields, for example, it’s possible for the conditions of the White Sea. It’s important, because there is no real marine observation networks for the Russian seas. So, the absence of the marine observation networks is the principal problem of real-time numerical sea modeling in our country. The results of testing the elements of real-time numerical modeling systems of the hydrological fields for the White and Barents Seas are presented in this paper.

Peculiarities of the processes of interconnected salinity fields and flows in the patches of unfrozen water behind the icebound coastal areas are analysed according to the results of numerical simulation. A three-dimensional unsteady hydrostatic model is used. The initial salinity distribution is taken to be double-layer. The salt flow caused by intensive ice generation in a coastal flaw polynya is specified by means of boundary conditions. The structure of interaction of salinity fields and flows is given in the process of generation.

Computer simulation is an important method for the analysis of the control quality and safety of ship and submarine motion. Recently, the computational simulation appears as a basis of methodology used in submarine design, also, in a motion control algorithm development (stabilization as well, as manoeuvering). At the same time, it is evident that a proof of the computer model adequacy may be obtained by comparison of the results of implementation of the pre-set experimental maneuver of the submarine with the results of the computer simulation for the same maneuver. The methodology of comparison of the results (identification of the mathematical description of the characteristics of the hull and control devices) and criteria of adequacy are the subject of the paper presented. The proposed method application is demonstrated by the test data obtained in the submarine vertical manoeuvers.

Density homogenous and non-homogenous fluid flows around a sphere or ellipsoid of revolution at high Reynolds and Froud numbers are studied on the basis of the vortex added-mass (LCS) method. The stratification influence upon the flow structure, shape of turbulent wake, dynamics of internal waves and integral characteristics of bodies are investigated. It has been shown that for the flow around a sphere located in the pycnocline the width of turbulent wake decreases and two types of waves are generated depending upon the internal Froud number values. In case of flows around an ellipsoid located under the pycnocline, short non-regular waves are produced and the drag force increases.

Authors consider the problem of soil scouring due to the effect of the ship propeller wake. Numerical simulation of the viscous flow is based on Reynolds equations closed with the help of the k – e turbulence model. The effects of the propeller are introduced by additional source terms incorporated in Reynolds equations. The potential erosion areas are found by comparing the computed shear stresses on the soil against the ultimate shear stresses that initiate the erosion process. The paper discusses several scenarios associated with ship operation in shallow waters. The numerical technique was used to establish dimensions and configurations of possible soil erosion patches and those conditions (depth, propeller loading, etc.), that are safe in terms of not causing bottom scouring.

The paper includes a review of the main problems of the ocean optics. It gives information about history of hydro-optics, inherent optical properties (IOP) of the natural waters, methods of IOP measurements, and physical and empirical models which allow to find relations between different IOP. The methods of solving the radiation transfer equation for quantitative data on natural and artificial, including pulsed, underwater light fields are considered. The main concern is with the methods of remote sensing of the ocean which are the most promising in terms of practical implementation. These meth ods are: determination of the concentrations of optically active matters (phytoplankton, sediment and dissolved organic matter) from data of multi-spectral ocean sensing; retrieval of the depth distributions of IOP and detection of the inner waves by oceanic lidars; detection of oil films on the sea surface; observation of underwater objects and the sea bottom by imaging systems placed on the submerged vehicles, ships, planes and satellites. A simple optical model of maritime atmosphere needed for computing the airborne and satellite -based imaging systems is given. The effect of rough sea surface on underwater object visibility is considered, as well as methods of correction of the images, distorted by surface waves.