Design and Study of Steady and Unsteady Flow around Open and Close Marine Propeller by SRANS and URANS Models

In this research, a standard propeller was designed for a surface vessel, then using a computer program, 3D propeller geometry based on two- dimensional data generated and griding and flow field around the propeller was solved based on the computational fluid dynamics method. In this regard, we used a hybrid grid and periodic condition based on a spline Cutting. A steady model and three unsteady models were used in the numerical modeling. The results were validated and uncertainty grid discretization error was calculated. The results were in good agreement with the results of open water, an estimated separation point and propeller wake were investigated. In order to modeling the transition of the boundary layer, two models of gamma and γ-Reθ transition were used. The Q criterion was used to detection vortices and wakes. The separation of flow and transition of the boundary layer from laminar to turbulent in high advanced coefficients in the unsteady models was different of the steady model. The effects of adding two standard duct with 19A and 37A with open propeller were compared that 19A duct had better hydrodynamic properties.