Design Exploration under Epistemic Uncertainties

Industrial design requires rapid investigation of various points in the design space. To perform these quick analyses, time intensive options such as Large Eddy Simulations (LES) or wind tunnel experiments are overlooked for the lower-fidelity, yet cost-effective Reynolds Averaged Navier-Stokes simulations. Although useful, assumptions inherent in the turbulence models used can introduce significant model-form errors that bring into question the reliability of these results. Quantification of these uncertainties would greatly improve the ability to design robust systems.

In spite of the substantial uncertainties in prediction due to turbulence models, at present, none of the available CFD software offer any utility to estimate these. In this talk, we outline the EQUiPS Module for quantifying the epistemic uncertainties due to turbulence models.

This module has been tested on a variety of canonical turbulent flows, as well as complex cases relevant to aerospace and turbomachinery design. Uncertainty bounds arising from these simulations are compared to available high-fidelity data. Coupled with design exploration tools, this provides a new automated approach to industrial design analysis and exploration with explicit estimation of model-form uncertainty.