1991 · 15 citations · 0 references
EngineeringComputational EngineeringMechanical EngineeringComputational Fluid DynamicsComputational MechanicsFluid DynamicsComputational AerodynamicsPropeller HydrodynamicsUnsteady AerodynamicsDucted PropellersNonuniform Inflow EffectsPanel Method AnalysisPropeller Computational Fluid DynamicsPropeller Inflow AnalysisPropeller-inflow NonuniformityUnsteady FlowUnsteady Flow Dynamics
The unsteady flow around an open marine propeller subject to a spatially nonuniform inflow is analysed by utilising a time marching potential based panel method. An efficient algorithm is implemented in order to ensure an explicit Kutta condition (i.e. pressure equality) at the blade trailing edge at each time step. The numerical method is shown to be very robust for a broad range of reduced frequencies as well as consistent with known analytic solutions and with an existing unsteady lifting surface method. A hybrid panel method is developed for the analysis of the unsteady flow around ducted propellers. It combines an unsteady lifting surface method for the propeller with a potential based panel method for the duct. The propeller is essentially treated with an existing time marching vortex lattice scheme which has been developed for open propellers, with the effects of the duct being accounted for via the generalised images of the propeller singularities with respect the duct. The proposed method is shown to be appropriate for treating unsteady ducted propeller flows in a computationally efficient and robust manner, especially when a given ducted propeller geometry must be analysed for various inflow conditions.