Automated Preprocessing Tools for Use with a High-Order Overset-Grid Algorithm

Author(s):  
Scott Sherer ◽  
Miguel Visbal ◽  
Marshall Galbraith
AIAA Journal ◽  
2011 ◽  
Vol 49 (7) ◽  
pp. 1387-1398 ◽  
Author(s):  
Kyung Rock Lee ◽  
Jung Ho Park ◽  
Kyu Hong Kim

Author(s):  
Scott E. Sherer ◽  
Miguel R. Visbal ◽  
Raymond E. Gordnier

A parallel, high-order, overset-grid method is validated for use in large eddy simulation (LES) through its application to turbulent flow problems. The current method employs a high-order, compact finite-difference approach to evaluate spatial derivatives, with up-to-tenth-order low-pass filters used to remove high-frequency spurious wave content. These filters have also been found to be effective in modeling the dissipation that occurs at the unresolved scales in the flow for LES simulations. Temporal integration is based on an implicit, approximately-factored and diagonalized, second-order algorithm, which reduces the time-step constraints present in explicit time-marching methods for wall-bounded viscous flows. Parallelization, geometric complexity, and local grid refinement are all addressed through the use of an overset-grid approach, with grid communication provided by high-order Lagrangian interpolation. Problems demonstrating this approach include fully turbulent channel flow and flows over a single circular cylinder, a general delta-wing configuration, and a realistic UAV geometry.


2013 ◽  
Vol 13 (2) ◽  
pp. 583-602 ◽  
Author(s):  
Andrea Lani ◽  
Björn Sjögreen ◽  
H. C. Yee ◽  
William D. Henshaw

AbstractThe variable high-order multiblock overlapping (overset) grids method of Sjögreen & Yee [CiCP, Vol. 5, 2009] for a perfect gas has been extended to nonequilibrium flows. This work makes use of the recently developed high-order well-balanced shock-capturing schemes and their filter counterparts [Wang et al., J. Comput. Phys., 2009, 2010] that exactly preserve certain non-trivial steady state solutions of the chemical nonequilibrium governing equations. Multiscale turbulence with strong shocks and flows containing both steady and unsteady components is best treated by mixing of numerical methods and switching on the appropriate scheme in the appropriate subdomains of the flow fields, even under the multiblock grid or adaptive grid refinement framework. While low dissipative sixth- or higher-order shock-capturing filter methods are appropriate for unsteady turbulence with shocklets, second- and third- order shock-capturing methods are more effective for strong steady or nearly steady shocks in terms of convergence. It is anticipated that our variable high-order overset grid framework capability with its highly modular design will allow for an optimum synthesis of these new algorithms in such a way that the most appropriate spatial discretizations can be tailored for each particular region of the flow. In this paper some of the latest developments in single block high-order filter schemes for chemical nonequilibrium flows are applied to overset grid geometries. The numerical approach is validated on a number of test cases characterized by hypersonic conditions with strong shocks, including the reentry flow surrounding a 3D Apollo-like NASA Crew Exploration Vehicle that might contain mixed steady and unsteady components, depending on the flow conditions.


2018 ◽  
Vol 363 ◽  
pp. 371-398 ◽  
Author(s):  
J. de Laborderie ◽  
F. Duchaine ◽  
L. Gicquel ◽  
O. Vermorel ◽  
G. Wang ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document