“…In this way, FD-Prim is algorithmically quite analogous to FVM, in that it first interpolates (rather than reconstructs) high-order Riemann states at each cell interface, then uses them to calculate interface fluxes by solving Riemann problems using either exact or approximate solvers, and finally makes corrections to the fluxes to deliver high-order-accurate FD numerical fluxes [57,60]. In this way the FD-Prim approach allows the added flexibility of choosing a Riemann solver (e.g., exact [66,67,68,33], HLL-types [69,70,71,72], or Roe [73], etc.) in a manner analogous to the FVM approach.…”