### LANS Publications

# "Sensitivities in Large Eddy Simulation and Improved Estimates of Turbulent Flow Functionals"

M. Anitescu and W. J. Layton

*SIAM J. Sci. Comput.*, vol. 29, no. 4, Society for Industrial and Applied Mathematics, , pp. 1650-1667. Also Preprint ANL/MCS-P1251-0505

Preprint Version: [pdf]

We consider a prototypical problem: simulate velocity and pressure in a turbulent flow using large eddy simulation (LES) and then use the results to estimate the force the underlying turbulent flow exerts on an immersed body. For eddy viscosity-type LES models we develop the appropriate continuous sensitivity equation and show how it can improve the functional estimate by using the sensitivity with respect to the user-selected length scale to incorporate the effects of the underlying unresolved small-scale fluctuations on the functionals sought.