A study to examine effects of the inflow interference on induced power using combined momentum and simple vortex theory inflow model

Abstract

This paper uses a recently developed combined momentum theory and simple vortex theory (CMTSVT) inflow model to study effects of rotor-on-rotor inflow interference on induced power predictions for different multi-rotor configurations with varying overlapping areas. The validation with the Harrington coaxial rotor shows that this analytical model, although simple, can capture the overall rotor-on-rotor wake interference effects in the estimation of rotor power, without a need for its coupling with a blade element rotor model. The first harmonic self-induced and interference inflow components of individual rotors are also available for further exploration of the different multi-rotor configurations. Hence, the CMTSVT model can serve as a viable tool for rapid estimation of rotor-on-rotor interference on overall power required in the early design stages of vehicle configuration and sizing trade studies.