Large-eddy simulation of marine flows over complex geometries using a massively parallel unstructured overset method

Abstract

Large-eddy simulation (LES) using an unstructured overset grid method (Horne and Mahesh, 2019) is used to explore several building-block problems of interest for submerged marine vehicles, including the bare and appended DARPA SUBOFF and the open and ducted propeller David Taylor Model Basin (DTMB) 4381 in crashback. An emphasis is placed on replicating the details of the experimental configurations and boundary conditions of these geometries, which is shown to be essential to reproduce certain aspects of their respective flow fields. The use of the overset grid method greatly reduces the set-up cost for these simulations, and LES results show good agreement with available experimental data. The consequences of boundary layer tripping methods and experimental confinement in crashback are discussed and physical insights made available from the LES data are presented.