A Predictive Wall Model for Laminar-Turbulent Transition for Large-Eddy Simulation

Speaker: Carlos A. Gonzalez, Johns Hopkins University Applied Physics Laboratory
June 4, 2026

Presentation

Abstract

Modeling of laminar-turbulent transition remains one of the key challenges in the numerical simulation of boundary layers, especially at coarse grid resolutions. Transition to turbulence strongly affects practical concerns such as wall-shear stress distribution and surface heat transfer. For wall-modeled large-eddy simulations (WMLES) specifically, the thin laminar region can require 10-100 times more grid points than the turbulent region to properly capture the amplification of disturbances preceding breakdown to turbulence (Slotnick et al., 2014). We propose to use the nonlinear parabolized stability equations (NLPSE) in conjunction with WMLES to simulate transitional flows affordably and accurately.

In the first part of the study, we develop the Falkner-Skan wall model (FSWM) for the simulation of laminar flow fields on coarse grids. The FSWM will be used in precursor simulations of transitional flows to generate accurate base flow states for our nonlinear parabolized stability analysis. The NLPSE are used to predict the location of transition and subsequently supply a spatially and temporally varying inflow condition for the WMLES. We demonstrate this approach for zero pressure gradient, flat plate H-type, K-type, and oblique transition scenarios. Computational cost savings and accuracy of the solutions will be discussed.

In the second part of this study, we extend the approach with the PSE-Sponge method, where we use sponge-like forcing in the LES equations to drive the solution closer to the more accurate PSE solution, directly within the simulation. This novel approach makes it less cumbersome to model transitional flows on complex geometries. We verify this approach on the same flat plate transition scenarios from the first section. Finally, this method is applied to simulating transition on a natural laminar flow NLF(01)-0416 airfoil.

Biography

Carlos A. Gonzalez is Senior Professional Staff in the Air and Missile Defense Sector at the Johns Hopkins University Applied Physics Laboratory. He received his Ph.D. in 2025 from the Department of Mechanical Engineering at Stanford University where he was advised by Professor Parviz Moin. His Ph.D. research was in the development of reduced order models to accurately simulate transitional flows using large-eddy simulation. At APL, he continues to work on transitional flows, as well as rarefied gas dynamics and signature rendering.

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