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.
