Ecological Systems and Devices Annotation << Back ESTIMATES OF THE PRESSURE FIELD INDUCED BY LONG INTERNAL WAVES WITHIN THE FRAMEWORK OF WEAKLY NONLINEAR THEORY S.A. Epifanov, A.S. Epifanova, O.E. Kurkina Determination of the fields of orbital velocity of fluid particles and dynamic pressure from internal waves, especially the peak values of these fi elds and their temporary variability, is important for assessments of the effects of intense regular and irregular waves on obstacles, engineering structures and bottom relief. In traditional approaches to the analysis of the dynamics of internal waves, to obtain evolutionary equations for the displacement of pycnoclines, the fields of density and wave pressure are usually excluded and not considered. In our study, based on the weakly nonlinear theory of long internal waves, series for variations in dynamical wave pressure are obtained in explicit form, and corrections to pressure in different orders of the weakly nonlinear theory are expressed through the displacement of the pycnocline, since most existing models of internal waves are focused on calculating the function h (z, x, t) (vertical displacement of the density isosurface corresponding to a fi xed density value in an unperturbed state at a selected horizon). This allows to combine in a universal numerical model both calculations of the field of displacements of isopicnal surfaces, and modeling of pressure changes caused by internal waves. A study of the spatial structure of wave dynamic pressure was carried out during the passage of stationary internal wave disturbances in a two – layer fluid. Keywords: internal waves, two-layer fluid, Korteweg-de Vries equation, dynamic pressure. DOI: 10.25791/esip.10.2023.1407 Pp. 67-78.