Research for the Leakage Characteristics of Spherical Pump Based on Micro Buoyancy Regulation System

The buoyancy regulation system is an important part of the Miniature Underwater Vehicles. In this paper, the principle of buoyancy regulation system of micro submersible model is designed according to the actual requirements. The structure and working mechanism of spherical pump is analyzed, the leakage equation of spherical pump is derived from Navier-Stokes equation in spherical coordinates. And the influence of clearance,working pressure, rotational speed and medium viscosity on the leakage of spherical pump is studied. At the working pressure of 0.3 MPa, the clearance is under 0.015mm, the leakage is less than 1.5*10
^-6
m
³
/s. While the clearance is larger than 0.015mm, the leakage increases rapidly. When the clearance of the spherical pump is greater than 0.02mm, the speed increases from 1600rpm to 4800rpm and the volumetric efficiency increases from 55% to 83%.