Reduced basis models for aero-thermal flows in buildings.


Wednesday, 12 September, 2018 - 16:00

When: Wednesday, September 12, 2018 at 4:00 pm

Where: SISSA main campus, room A-133

Speaker: Dr Enrique Delgado, formerly at University of Sevilla, Spain, now SISSA mathLab

Title: Reduced basis models for aero-thermal flows in buildings.

Abstract:  In this work, we consider several models with increasing complexity, for which we develop the reduced order techniques applied to these models. We perform a stability study for these models and numerical simulations that validate the theoretical results obtained. We present in a first step a RB Smagorinsky model, that is the basic LES model, in which a non-linear eddy viscosity is considered for the Navier-Stokes equations. The linearisation of the non-linear eddy viscosity terms becomes essential to get big speedups in the computation of the reduced basis solution. Then we consider a Variational Multi-Scale (VMS) Smagorinsky model, in which the eddy viscosity only acts on the small resolved scales, with Local Projection Stabilization on the pressure. The consideration of the Local Projection Stabilization on the pressure also in the RB model let us avoid the enrichment of the reduced velocity space with the inner pressure supremizer. Finally, we consider a Boussinesq VMS-Smagorinsky model in which the buoyancy forces are taken into account. For this model, we present numerical results in which both physical and geometrical parameters are considered.