This project seeks to perform large-eddy simulation (LES) of flow over a realistic aircraft geometry. The team’s aim is to demonstrate, for the first time, the predictive capability of low-dissipation LES methodologies for practical external aerodynamics configurations. The major obstacle in accomplishing this goal is the presence of energetic near-wall eddies with diminishing length scales as one approaches the wall. Resolving such small but dynamically important near-wall eddies is infeasible even with the supercomputers to be introduced in the next decade.
The team is addressing this issue by modeling the effect of the small-scale near-wall turbulence on the large-scale resolvable fluid motion in the outer portion of the boundary layer. This concept of wall modeling is now deemed indispensable for enabling predictive but affordable LES of practical aeronautical flows. However, application of wall-modeled LES (WMLES) to date has been confined largely to studies of canonical flows involving relatively low Reynolds numbers and mostly two-dimensional geometries. To this end, the team plans to conduct WMLES of the National Aeronautics and Space Administration (NASA) Common Research Model (CRM) and the high-lift JAXA Standard Model (JSM), which are community research models for commercial transport aircraft. The high-fidelity simulation of the NASA CRM is considered a grand challenge problem for computational fluid dynamics.
Successful calculation of these engineering flows would facilitate the use of high-fidelity simulation techniques to help design future aircraft, particularly in take-off and landing configurations that have been difficult to predict using lower fidelity techniques.