Haar-type stochastic Galerkin formulations for hyperbolic systems with Lipschitz continuous flux function

This work is devoted to the Galerkin projection of highly nonlinear random quantities. The dependency on a random input is described by Haar-type wavelet systems. The classical Haar sequence has been used by Pettersson et al. (J Comput Phys 257:481–500, 2014) for a hyperbolic stochastic Galerkin formulation of the one-dimensional Euler equations. This work generalizes their approach to several multi-dimensional systems with Lipschitz continuous and non-polynomial flux functions. Theoretical results are illustrated numerically by a genuinely multi-dimensional CWENO reconstruction.