Flow of liquids through ring-type slots at high pressures

The purpose of the present activity is definition of rate of flow through a narrow ring-type slot at a difference of pressure up to 1 GPa. Such a flow of a liquid takes place, for example, in a radial space of a system, the cylinder piston-barrel used in different hydraulic units of high-pressure. A feature of the problem is the change of geometry of a gap and physical characteristics of a liquid (density and viscosity) at high pressures and temperatures (the liquid in a gap is heated at the expense of viscid friction)