Nonlinear Aerodynamic Corrections to Blade Element Momentum Model with Validation Experiments

Blade element momentum theory is well suited for propeller analysis during the early stages of design. The analytic blade element momentum model is presented along with a proposed nonlinear improvement. The analytical model makes small angle assumptions which are known to be inaccurate under some conditions. The nonlinear model avoids these assumptions. The results of the analytical and nonlinear models are compared against each other. The differences between these are most prevalent on lower pitch propellers at high advance ratios. A wind tunnel validation test is outlined. Results of the validation test and other published data from the University of Illinois at Urbana-Champaign are compared to the analytical and nonlinear blade element models. The test data matches the nonlinear data with reasonable accuracy at high advance ratios