An overset-mesh approach for large-Eddy simulation of high-Reynolds number aerofoil flow

ABSTRACT

Wall-resolved large-eddy simulations are carried out in order to explore the use of an overset nested-grid approach for computing high-Reynolds number turbulent aerofoil flows. By lowering the computational grid density as the distance from solid surfaces increases, a saving in computing resources may be realised. The configuration consists of a wing section having a NACA0012 aerofoil geometry, at a freestream Mach number of 0.3 and chord-based Reynolds number of $3\times {10}^6$, which duplicate experimental conditions. Two angles of attack are considered, namely 0.0${}^{\circ }$ and 9.86${}^{\circ }$. Because of the limited amount of experimental data available at the aerofoil Reynolds number, well-resolved solutions are obtained without employing the nested-grid technique and are then used to validate the overset methodology. All results are obtained with a high-fidelity numerical method, using high-order interpolation to maintain spatial accuracy with the overset systems. A comprehensive, detailed comparison is made between solutions obtained with a single-block grid topology, and those generated on nested overset-mesh systems. The quantities considered, consist of time-mean and fluctuation velocity profiles, as well as turbulent kinetic energy spectra. It is shown that comparable results may be obtained with a resource saving of 52–65% by utilising the nested-grid approach.

KEYWORDS:

• Large-eddy simulation
• high-Reynolds number aerofoil
• high-order numerical method
• nested-grid approach
• high-order interpolation

Acknowledgments

The authors are grateful for many helpful conversations with N. J. Bisek and D. J. Garmann. They also wish to thank S. I. Benton for providing XFOIL results.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This material is based upon work supported by the Air Force Office of Scientific Research under award number FA9550-17RQCOR393, monitored by D. Smith. Computational resources were supported in part by a grant of supercomputer time from the U.S. Department of Defense Supercomputing Resource Centers at the Stennis Space Center, MS and Wright-Patterson AFB, OH.