A semi-empirical multi-degree of freedom body force propeller model. (15th April 2019)

• Record Type: Journal Article
• Authors: Knight, Bradford G.; Maki, Kevin J.
• Is Part Of: Ocean engineering. Volume 178(2019)
• Page Start: 270
• Page End: 282
• Publication Date: 2019-04-15
• Subjects: Propeller -- CFD -- Body force model -- Semi-empirical algorithm; Ocean engineering -- Periodicals; Ocean engineering; Periodicals; 620.4162
• DOI: 10.1016/j.oceaneng.2019.02.056
• Languages: English
• ISSNs: 0029-8018

Abstract

Abstract: Efficient and accurate modelling of a self-propelled vessel in a large amplitude seaway with CFD-based numerical methods is a challenging task and is prohibitively expensive for most designers and engineers. Viscous CFD methods can accurately model viscous effects, but the small numerical time step required to analyze the rotating propeller leads to a large computational cost. A method for efficiently and accurately modelling the six degree of freedom force on the propeller is required to feasibly model a self propelled vessel maneuvering in a high amplitude seaway. This paper outlines the framework for developing an unsteady body force propeller model for unsteady conditions. The purpose of this study is to train a semi-empirical algorithm to accurately prescribe the unsteady body force to model the propeller. The MOERI Container ship propeller is analyzed with RANS CFD. Open water data is compared to the RANS CFD results of a steady Moving Reference Frame approach. Unsteady surge and propeller revolution rate are applied to a transient rotating mesh model in open water and behind condition. The predictions of the algorithm match well with the CFD results.