Pattenden, R.J., Turnock, S.R. and Bressloff, N.W.
Developments in the use of large eddy simulation for ship hydrodynamics
At The 3rd International 'Computational Fluid Dynamics in Ship Hydrodynamics' Conference (CFD2003).
06 - 07 Feb 2003.
A summary is given of the work being carried out at the University of SOuthampton on the use of large-eddy simulation (LES) for marine hydordynamics. The case of a truncated cylinder on a ground plane has been used to test an in-house code by comparisons with experimental data. This has shown that the LES model performs well in separated and vortical flow regions, but has limitations in its ability to capture boundary layer flow. Further wind tunnel experiments also used particle image velocimetry (PIV) to measure the instatneous flow field in the stern region of the KRISKO VLCC tanker form. LES simulations of an eliptical body, of similar proportions to the tanker form, illustrate similarities both to the VLCC flow structure and to that of the truncated cylinder. In particular, for all three geometries the instantaneousflow field contains many more large-xcale turbulent structures in the wake with a much greater range of vorticity magnitude than in the mean vorticity field. This suggests that LES may give more accurate results than a steady RANS method for ship flows, if the computational cost of resolving the boundary layer can be reduced. Initial simulations of a two-dimensional cylinder flow have been carried out using detached-eddy simulation 9DES), a hybrid RANS/LES technique, which is less demanding of grid resolution than full LES, and which could offer such a route.
Actions (login required)