A numerical model of the blade element momentum theory for rotating airfoils with heat transfer calculation

As a joint collaboration between university and industry to develop tools for low power deicing of helicopter blades, the heat transfer required to deice a tail rotor needs to be calculated. The last 20 years of research relied mostly on CFD and experimental setups for that purpose, a rather time consuming solution. The main objective of this paper is to elaborate a numerical model to quickly compute the non-dimensional heat transfer on a helicopter tail rotor. The Blade Element Momentum Theory is used to predict rotor aerodynamic performance and heat transfer calculation across the span of the blades is done using pre-verified, CFD determined, set of correlations for the NACA0012 and NACA4412. First, rotor performance is validated and verified against experimental and numerical results for a set of 2, 3, 4 and 5 bladed rotor from the National Advisory Committee for Aeronautics. The thrust is over predicted by 10% and the torque is under predicted by 15% compared to experimental data. Second, a parametric study is done to understand the effect of blade geometry on heat transfer. Finally, θ is found to influence stall most, whereas changes in Ω and c led to an increase in Nu by up to a multiple of 5 for higher rotor speeds.