Propeller-Duct Interaction Due to Loading and Thickness Effects.

This study is a continuation of an earlier investigation dealing with the interaction of a propeller and its enshrouding nozzle when both are operating in a nonuniform inflow field. The present investigation complements the previous one by introducing thickness of both lifting surfaces and camber of the duct. Thus a complete analysis is available which takes into account the true geometry of the propeller and duct, including the propeller and duct thickness and duct camber distributions along with the camber and flow angle of the propeller and the conicity angle of the duct. A computer program adaptable to a high-speed digital computer has been developed which evaluates the steady and time-dependent pressure (loading) distributions on both lifting surfaces and the resulting hydrodynamic forces and moments generated by the propulsive device. Provision has also been made in the analysis and program to deal with a nonaxisymmetric nozzle and a tilted nozzle.