Numerical and experimental study on the minimum sensitivity to the azimuth angle of underwater vehicle speedometry using differential pressure sensors

One of the important parameters in the navigation of an intelligent subsurface vehicle is to estimate the speed with appropriate accuracy. One of the available methods for measuring the speed under the surface is the use of differential pressure sensors. In this study, in order to achieve the lowest sensitivity to the azimuth angle of the water flow in the subsurface, the optimal place of installing pressure gauge sensors on the forehead of a cylindrical geometry has been considered. In this study, experimentally and numerically, nine positioning angles of the sensors with respect to the top of the cylinder have been investigated as an effective parameter in six specific speeds and five flow attack angles. The results of these investigations have shown that the best estimation of the speed in the subsurface can be achieved with the positioning angle of the sensors in the range of 35 degrees and with the lowest sensitivity to the azimuth angle (5% difference with the reference speed).