Investigations of 3D Turbulent Flow Inside and Around a Water-Jet Intake Duct Under Different Operating Conditions

Abstract

In this paper the flow field in the intake duct of a model water-jet unit is studied by using a commercial 3D CFD code. In order to model the intake duct/hull interaction, the computational domain includes a large section of the hull in the vicinity of the intake duct opening. Appropriate boundary conditions are used on the far upstream and downstream of the duct inlet in order to minimize the effect of the domain boundaries on the flow field in the vicinity of the intake duct. Computations are performed for different boat speeds and flowrates. In addition, the effects of the impeller shaft, shaft rotation, boat trim as well as the traverse flow across the hull are investigated. The results of the computations are compared with some preliminary experimental results obtained from model self-propulsion tests in a towing tank. Good correlation is obtained between the predictions and the experimental results.