Gas-heated hollow propeller blades have been investigated both analytically and experimentally to determine heat requirements for the prevention of icing on the blade surfaces during flight.
An analysis was made of a typical hollow propeller blade to determine the internal gas flow and temperature required to maintain the external surface temperature above 32 F.
The basic wet-air equation is given and curves are presented to illustrate the blade heating and temperature distributions which were obtained for one set of conditions. Full-scale gas-heated propellers have also been investigated experimentally in an icing wind tunnel and typical results are presented.
The rates of heating required to prevent icing are discussed and a modification of propeller blade interiors by using fins and partitions is shown by comparative experiments to permit large reductions in the required heat-source input.