Comparison of Numerical Simulations of Propeller Open-Water Performance with Cavitation for High-Speed Planing Hulls

Abstract

Numerical simulations of an open-water propeller are performed using CFDShip-Iowa. The propeller, originally designed by Mercury Marine for a 21 feet high-speed planing hull, is scaled to match a 42 feet hull configuration. Three advance ratios (J = 0.8, 1.1, and 1.4) and two cavitation numbers (σ = 0.274 and 1.095) are considered in the computations, and the results are compared with those obtained from the commercial CFD solver STAR-CCM+. For the fully wetted conditions without cavitation, the overall trends of the computed thrust (Kt), torque (Kq), and propeller efficiency (η) with respect to the advance ratios are similar. The computed Kt, Kq, and η with cavitations generally agree with the STAR-CCM+ results except for η at σ = 0.274, where the latter shows a much higher value for J = 1.4. For σ = 1.095, the cavitation patterns and overall pressure distributions are similar for both codes. For σ = 0.274, the cavitation is more violent for CFDShip-Iowa than STAR-CCM+. CFDShip-Iowa shows better preservation of the cavities and blade-to-blade interactions, which are not captured in the simulations using STAR-CCM+, since a single blade with periodic boundary conditions are used.

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