Computational Study of a UCAV Configuration Using a High-Order Overset-Grid Algorithm

2008 ◽  
Author(s):  
Scott Sherer ◽  
Raymod Gordnier ◽  
Miguel Visbal
Keyword(s):  
Computational Study ◽  
High Order ◽  
Overset Grid ◽  
Grid Algorithm

High-Order Interpolation Method for Overset Grid Based on Finite Volume Method

AIAA Journal ◽  
2011 ◽  
Vol 49 (7) ◽  
pp. 1387-1398 ◽  
Author(s):  
Kyung Rock Lee ◽  
Jung Ho Park ◽  
Kyu Hong Kim
Keyword(s):  
Finite Volume Method ◽  
Finite Volume ◽  
Interpolation Method ◽  
High Order ◽  
Overset Grid ◽  
Volume Method ◽  
High Order Interpolation ◽  
Grid Based

scholarly journals A Computational Study on the Aerodynamic Influence of a Propeller on an MAV by Unstructured Overset Grid Technique and Low Mach Number Preconditioning

2012 ◽  
Vol 5 (1) ◽  
pp. 11-21 ◽  
Author(s):  
S. Deng ◽  
B. W. van Oudheusden ◽  
T. Xiao ◽  
H. Bijl
Keyword(s):  
Computational Study ◽  
Aerodynamic Performance ◽  
Moving Boundaries ◽  
Simulation Tool ◽  
Overset Grid ◽  
Low Mach Number ◽  
Speed Flow ◽  
Grid Approach ◽  
Preconditioning Method ◽  
Grid Technique

The influence of a propeller on the aerodynamic performance of an MAV is investigated using an unstructured overset grid technique. The flow regime of a fixed-wing MAV powered by a propeller contains both incompressible regions due to the low flight speed, as well as compressible flow areas near the propeller-tip region. In order to simulate all speed flow efficiently, a dual-time preconditioning method is employed in the present study. The methodology in this paper is verified as providing a reliable numerical simulation tool for all flow regimes, in the additional presence of moving boundaries, which is treated with an overset grid approach.

A High-Order Overset-Grid Approach for Large Eddy Simulations

2007 ◽  
Author(s):  
Scott E. Sherer ◽  
Miguel R. Visbal ◽  
Raymond E. Gordnier
Keyword(s):  
Delta Wing ◽  
Temporal Integration ◽  
Grid Method ◽  
Current Method ◽  
Turbulent Channel Flow ◽  
High Order ◽  
Overset Grid ◽  
Time Step ◽  
Grid Approach ◽  
Large Eddy

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.

scholarly journals Variable High-Order Multiblock Overlapping Grid Methods for Mixed Steady and Unsteady Multiscale Viscous Flows, Part II: Hypersonic Nonequilibrium Flows

2013 ◽  
Vol 13 (2) ◽  
pp. 583-602 ◽  
Author(s):  
Andrea Lani ◽  
Björn Sjögreen ◽  
H. C. Yee ◽  
William D. Henshaw
Keyword(s):  
Modular Design ◽  
Numerical Approach ◽  
High Order ◽  
Shock Capturing ◽  
Overset Grid ◽  
Chemical Nonequilibrium ◽  
Optimum Synthesis ◽  
Filter Methods ◽  
Adaptive Grid Refinement ◽  
Nonequilibrium Flows

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.

Sign in / Sign up

Export Citation Format

Share Document