DATE:                        Thursday 3.21.24 

TIME:                         4:00pm

LOCATION:             31-270

SPEAKER:               Adrián Lozano-Durán, Draper Assistant Professor of Aeronautics and Astronautics

TOPIC:                      Building-block Flow Model for Computational Fluids

Abstract: The predictive capabilities of computational fluid dynamics (CFD), critical for aerodynamic design, hinge on the development of accurate closure models. However, no practical model has emerged as universally applicable across the broad range of flow regimes of interest to the industry. We introduce a closure model for CFD, referred to as the Building-block Flow Model (BFM). The foundation of the model rests on the premise that a finite collection of simple flows encapsulates the essential physics necessary to predict more complex scenarios. The BFM is implemented using artificial neural networks and introduces five unique advancements within the framework of large-eddy simulation: (1) It is designed to predict multiple flow regimes (laminar flow, wall turbulence under zero, favorable, and adverse mean-pressure gradients, separation, statistically unsteady turbulence, and wall roughness effects); (2) It leverages information-theoretic dimensional analysis to select the most relevant non-dimensional input/output variables; (3) It ensures consistency with numerical schemes and gridding strategy by accounting for numerical errors; (4) It is directly applicable to arbitrary complex geometries; (5) It can be scaled up to model additional flow physics in the future if needed (e.g., shockwaves and laminar-to-turbulent transition). The BFM is utilized to predict key quantities of interest in a wide range of cases, such as turbine blades with roughness, speed bumps, and aircraft in landing configuration. In all cases, the BFM demonstrates similar or superior capabilities in terms of accuracy and computational efficiency compared to previous state-of-the-art closure models. We also discuss ongoing efforts to extend the model to supersonic and hypersonic flows with applications to Entry, Descent and Landing (EDL) vehicles.