CFD modelling of a fan with a cycloidal rotor

Abstract

Despite the wide possibilities of using a cycloidal rotor in the form of propulsion systems for unmanned aerial vehicles (UAV), cycloidal propellers for sea-going ships, rotors of wind turbines or sea or river cycloidal energy converters, there is practically no research on the use of this solution in the form of a cycloidal rotor fan (CRF) for HVAC (heat, ventilation & air conditioning) applications. The main features of such a machine, compared to conventional solutions, is a possibility of changing the flow direction only by changing pitch angles of the rotor blades. This study analysed two variants of the fan, first equipped with an asymmetrical CLARK Y profile, and other with a symmetrical NACA0012. Numerical simulation of cycloidal rotor fan developed in Ansys CFX was presented, that enables the simulation of fan operation. The results obtained from CFD for both variants were compared with those obtained during experimental measurements made with the use of Laser Doppler Anemometry (LDA). The comparison showed good agreement between the numerical analysis and the performed experiment. Despite the operation based on the same cycloidal regulation settings and rotation speed, the fan equipped with symmetrical blades slightly more curved the flow angle than the asymmetrical one.