Toward computing sensitivities of average quantities in turbulent flows

Understand

Chaotic dynamical systems such as turbulent flows are characterized by an exponential divergence of infinitesimal perturbations to initial conditions.

• Therefore, conventional adjoint/tangent sensitivity analysis methods that are successful with RANS simulations fail in the case of chaotic LES/DNS.
• In this work, we discuss the limitations of current approaches, including ensemble-based and shadowing-based sensitivity methods, that were proposed as alternatives to conventional sensitivity analysis.
• We propose a new alternative, called the space-split sensitivity (S3) algorithm, that is computationally efficient and addresses these limitations.