Hydro-elastic computational analysis of a marine propeller using two-way fluid structure interaction

Marine propellers have complex geometry and their performance is determined by costly and time consuming open water experiments. Use of numerical techniques helps researchers in effective design of propellers. Several approaches are used that predicted either hydrodynamic and acoustic response or structural response. Two-way fluid-structure interaction (FSI) analysis is a very useful approach providing all three responses which helps in the design, analysis and optimization of a propeller. The objective of this paper is to predict the hydro-elastic response of a propeller using two-way FSI on a 0.2m diameter, DTMB-4119 propeller using ANSYS software. Two-way FSI analysis is carried out using system coupling approach that transfers the data between the structural and fluid solvers. The turbulence effects are captured using the large-eddy simulation (LES) model and the Ffowcs Williams Hawkings (FWH) acoustic model is used for evaluating the sound pressure level (SPL) generated by propeller. Analysis is extended to evaluate the hydro-elastic and acoustic response of the propeller after validating the hydrodynamic performance with the experimental result in the literature. The results from Two-way FSI analysis are in close agreement when compared with the one-way FSI analysis. Two-way FSI can accommodate the peak value of stress and deformation developed during the initial part of the transient solution which is important in the design of propeller. This study reveals that metallic (NAB) propeller can be replaced by a composite propeller. The acoustic response from two-way FSI analysis will be more realistic due to the consideration of hydro-elastic effect of propeller.