Wall-resolved large-eddy simulation (LES) is used to simulate flow over an axisymmetric body of revolution at a Reynolds number, Re = 1:1 × 106, based on the free-stream velocity and the length of the body. The geometry used in the present work is an idealized submarine hull (DARPA SUBOFF without appendages) at zero angle of pitch and yaw. The computational domain is chosen to avoid confinement effects and capture the wake up to fifteen diameters downstream of the body. The unstructured computational grid is designed to capture the fine near-wall flow structures as well as the wake evolution. LES results show good agreement with the available experimental data. The axisymmetric turbulent boundary layer has higher skin friction and higher radial decay of turbulence away from the wall, compared to a planar turbulent boundary layer under similar conditions. The mean streamwise velocity exhibits self-similarity, but the turbulent intensities are not self-similar over the length of the simulated wake, consistent with previous studies reported in the literature. The axisymmetric wake shifts from high-Re to low-Re equilibrium self-similar solutions, which were only observed for axisymmetric wakes of bluff bodies in the past.
Bibliographical noteFunding Information:
This work is supported by the United States Office of Naval Research (ONR) under ONR grant N00014-14-1-0289 with Dr K.-H. Kim as technical monitor. The computations were made possible through the computing resources provided by the US Army Engineer Research and Development Center (ERDC) in Vicksburg, Mississippi on the Cray XE6, Copper and Garnet of High Performance Computing Modernization program (HPCMP). This research partly used the computer time provided by the Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program on the resources of the Argonne Leadership Computing Facility (ALCF), which is a DOE Office of Science User Facility supported under Contract DE-AC02-06CH11357. The authors thank Mr S. Anantharamu for his help with the grid pre-processing needed for the massively parallel computations reported in this paper.
© 2018 Cambridge University Press.
- turbulence simulation
- turbulent boundary layers