Non-intrusive reduced order models for the accurate prediction of bifurcating phenomena in compressible fluid dynamics

The present works is focused on studying bifurcating solutions in compressible fluid dynamics. On one side, the physics of the problem is thoroughly investigated using high-fidelity simulations of the compressible Navier- Stokes equations discretised with the Discontinuous Galerkin method. On the other side, from a numerical modelling point of view, two different non -intrusive reduced order modelling techniques are employed to predict the overall behaviour of the bifurcation. Both approaches showed good agreement with full -order simulations even in proximity of the bifurcating points where the solution is particularly non -smooth.