статья в журнале

En

Physical Oceanography

ISSN:0928-5105
eSSN:1573-160X

2019

10.22449/1573-160X-2019-5-374-386

Purpose. The paper is aimed at studying both resonance response of a system of two model bays to the initial disturbance of free surface induced by the sea bottom motion and mutual influence of the adjacent bays. Methods and Results. Based on the numerical hydrodynamic ADCIRC model, including the method of finite elements, studied is the resonance response of two adjacent bays (A and B; rectangular form, certain dimensions and depths) similar to the Sevastopol and Karantinnaya bays, respectively, to the initial disturbance of free surface induced by the sea bottom motion. The calculations were carried out at different dimensions of the initial disturbance area both for the system of two adjacent bays and individually for each bay. Conclusions. Initial disturbance generates in the Bay A four lowest modes of eigen-oscillations with the periods 45, 15, 9 and 6 min., and in the bay B - two lowest modes with the periods 12 and 4 min. The obtained periods are in good agreement with the analytical estimates. Presence of the adjacent bay gives rise to intensification of the Helmholtz mode in each of them. External disturbance with the period 11.7 min. constitutes potential danger for the bay B since, in such a case, resonance with its Helmholtz mode occurs. The analytically obtained dependence between the periods of the infragravity waves and the average periods of the wind waves in the Sevastopol region (resulted from the retrospective analysis of waves) permitted to reveal theoretical possibility of generating short-period seiches by the infra-gravity waves in both bays.

SEVASTOPOL BAY, SEICHES, RESONANCE OSCILLATION, INFRA-GRAVITY WAVE, NUMERICAL MODELING, ADCIRC

2019-12-12 15:49:00