P. Beaumier et al., CFD DRAG AND POWER PREDICTION FOR A ROTOR IN HOVER OR FORWARD FLIGHT - FORMULATION AND FIRST APPLICATIONS, Journal of the American Helicopter Society, 42(4), 1997, pp. 327-336
Two general formulations based on the momentum equations are developed
in this paper, They both aim at predicting the power consumed by a ro
tor from a given field solution. The first formulation concerns forwar
d night configurations for which the inviscid flow-field around the bl
ades is calculated using the 3D unsteady Full Potential equations and
the second one concerns hover configurations modeled using a 3D Euler
solver. In each case, the computational method can be coupled to a 3D
laminar-turbulent boundary layer code in order to have access to the v
iscous drag. The theoretical aspects are first validated, then applied
to non-lifting as well as lifting configurations. Results in forward
flight present a reasonable agreement with experiment (for the torque
prediction). In hover, the database used for the comparisons did not i
nclude values for the power consumed by the rotor. This study shows th
at drag and power predictions with the use of CFD methods for helicopt
er configurations is not unrealistic and can bring a better understand
ing of the drag production mechanisms.