Abstract

The process of designing technical objects involves determination of geometrical parameters that characterize a given device. When device operation is described by differential equations, an inverse problem brings difficulties, as geometrical values being sought condition the solution to the problem. Vortex separators, used for removal of suspension from storm wastewater are usually designed by the ‘criterion method’. Firstly, a critical particle is distinguished such that bigger particles are removed from wastewater stream, whereas smaller particles stay in the stream. Next, by comparing values of major forces acting on the critical particle at the most unfavourable point within the separator (usually at outflow cross-section), a force balance is made. The resulting algebraic relation becomes the design criterion.