Self-similar approach to determining the vertical distribution of sound speed in the active layer of the ocean

by

A.N. Grekov, N.A. Grekov

Institute of Natural and Technical Systems, RF, Sevastopol, Lenin St., 28

E-mail: oceanmhi@ya.ru

DOI: 10.33075/2220-5861-2024-4-47-56

UDC 681.883                                           

EDN: https://elibrary.ru/kdutwq

Abstract:         

The article analyzes various methods for obtaining the vertical distribution of sound velocity (VDSV), including construction models and hardware for their measurement. To determine the VDSV at the sites, the authors propose their own approach to this problem, which is based on the use of self-similarity of the oceans together with an information-measuring system equipped with simple systems for measuring the speed of sound. An algorithm for the operation of the information-measuring system and its structural and functional diagram are presented. To confirm the operation of the proposed model, in-kind measurements of sound velocity stratifications at 51 stations obtained at the marine testing site were used. Estimates of the self-similar profiles of the speed of sound for the entire testing site were made and calculations were performed for the entire time series (37 h) with averaging over the entire layer relative to the reference profile. The calculation results are presented in the form of graphs of the joint distribution of the speed of sound of the true profile and the self-similar profile, and the absolute difference in the speed of sound depending on the depth z between the true and self-similar profiles is given. For one of the stations, a typical maximum divergence in sound speed is given, which is observed in the layer from 10 to 25 m and is +0.12 m/s. Below this layer, the maximum divergence does not exceed ±0.05 m/s, which fully satisfies many acoustics problems.

Keywords: methods, models, hardware, information and measuring system, speed of sound, ocean, sea, algorithm, measurement, self-similar restoration.

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