Influence of water area depth on wind waves

A semi-empirical technique for calculating the parameters of wind waves at variable sea depths along the wind acceleration has been developed and presented. This technique allows you to determine the average values of wind wave heights, their length and period depending on the wind velocity, taking into account and without taking into account the heaping of water by wind. Within the framework of the described method, the calculations of wind wave parameters suitable for isobaths d = 20 m were performed for a specific study area of the Bistre (Novostambulske) branch of the Danube estuary, for the north-eastern and eastern wind directions. Numerical simulations were performed for the Black Sea in the location of the protection dam of the Maritime approach channel of the Danube-Black Sea deep-sea navigation. Numerical calculations of wind wave transformation in the water area near the protection dam for the most dangerous wind directions in stormy conditions were performed. For mathematical simulation, the maximum values of wind velocity and wave height were used, which were observed during the whole period of research of the Black Sea water area in the region of the dam. Within the framework of refraction theory, wave transformation calculations have been performed for the most wave-hazardous wind acceleration directions, namely, the north-eastern and eastern wind directions. It is shown that taking into account the heaping of water by wind leads to an increase in the parameters of gravitational waves. The results of numerical simulations have shown that with the increase of wind acceleration exceeding the limit values, the parameters of the waves reach constant values. These values depend on the bathymetry of the seabed, wind velocity and direction. It was found that the increase in the deviation of the free surface of the sea from the undisturbed level significantly depends on the heaping of water by wind. It was found that the relative increase in the wave parameters is observed higher in the east wind direction than in the northeast wind direction in the study area of the Black Sea.