Title: RANS Modeling for Taylor-Green Vortex Transition and Decay

By: Daniel M. Israel, Ph. D.

XCP-4: Methods & Algorithms, Los Alamos National Laboratory

ABSTRACT: Conventional RANS models relate the destruction terms in all transport equations by tunable linear coefficients. This fixes a constant decay rate in homogeneous decaying turbulence, contrary to experimental evidence. It also cannot account for production of dissipation in transition. The current work demonstrates the modeling potential of using the exact dissipation rate equation, in terms of the unknown skewness and palinstrophy. The test case is the Taylor-Green vortex with and without a passive scalar. Along the way, we will ask whether the region of interest ever actually includes the asymptotic state of the theory.

BIO: Daniel Israel received his Ph.D. in Aerospace Engineering from the University of Arizona in 2005. He joined Los Alamos National Laboratory as a post-doc, and became a staff member in 2008. During his time at Los Alamos, he has primarily worked in turbulence modeling, with a focus on multi-species mixing, buoyancy-driven turbulence, RANS, LES and hybrid modeling, and reduced-order models for turbulent flows. He also served for two years as the lead of the Physics Verification project. For the past three years he has been the organizer for the Los Alamos Computational Physics Student Summer Workshop.

Friday, September 24th from 3:00 p.m. – 4:00 p.m.

Attend in person projection in JH-109 or via Zoom (https://nmsu.zoom.us/j/98101382682).

If you are interested in visiting our department and giving a seminar lecture, please send an e-mail to Dr. Andreas Gross.