A wake rollup model for heavily loaded marine propellers

Hydrodynamic modelling of the wake geometry of a propeller is one of the most important problems in the propeller theory. A variety of wake models have been proposed in the literature. In the present study, the flow field around the propeller has been represented by an unknown potential employing surface panel method, known as the Morino method. The proper wake shape is found by a method which is developed specifically for heavily loaded marine propellers. The method makes use of the streamlines of the propeller due to the fact that wake surface has to be a stream surface. Therefore contraction and rollup occur along the downstream direction in a natural way without the necessity of an ad hoc correction factor. It is shown that the numerical results for rectangular wings are in good agreement with theoretical results in a wide range of angles of attack and also the open water characteristics of the propeller calculated by the method are in good agreement with experimental data.