Method for determining t he device immersion depth in the sea during sounding

by

V.A. Gaisky

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

E-mail: gaysky@inbox.ru 

DOI: 10.33075/2220-5861-2022-4-40-45

UDC  556.082                                                                                                                    

Abstract:

   In well-known methods, the device immersion depth in the sea is determined by the measured hydrostatic pressure and, at the same time, the dependence of depth on pressure obtained for a certain “standard” static ocean (sea) with an average salinity and temperature is used.

   For regional waters, amendments are introduced if they are known. Such a solution does not guarantee the claimed errors in determining the depth above 10-3, since the real object is non-stationary in time and space.

   The accuracy of determining the depth of the probe in real environment and in real time can be increased if during sounding the local density is measured simultaneously with the measurement of hydrostatic pressure.

   In this case, the depth of the probe will be equal to the sum of the distances traveled by the probe from one pressure value to another and equal to the pressure increment divided by the product of the average local density and the acceleration of gravity.

   Changing the device immersion depth when moving down or up and being on the foot is controlled. The method can be used to control the immersion depth when the underwater vehicle or towed device is moving.

   A feature of the method is the averaging of the result over many readings with the suppression of random components of instrumental errors and random noise caused by the vertical movement of the medium.

   Due to this, it is possible to obtain the resulting guaranteed accuracy of determining the immersion depth of the order of 10-4.

Keywords: immersion depth, hydrostatic pressure, local density.

To quote: 

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