FLOW FIELDS IN THE CONICAL CHANNEL OF MICRO HYDROPOWER CONVERTER IN PRESENCE AND IN ABSENCE OF TURBINE STAGES

For a new concept of micro hydropower converter with positioned in gravitational vortex flow multistage turbine rotor with different values of specific speed has been modeled the velosity field of water flow through the conical channel in the absence of the turbine stages and was determined the flow structure by the computer simulation in the presence of the turbine stages. In the first case, the stream lines appear as helical spirals. The distributions of circular, radial and axial velocity components in the boundary layer, in the potential flow (zone of the free vortex) and in the forced vortex was determined. In the second case the structure of the water flow is changes with the formation of individual swirls in every area between the blades. The water velocity increases rapidly as proximity to the drain hole and strongly depends on sink and vortex strengths.