Riemann-Problem and Level-Set Approaches for Homentropic Two-Fluid Flow Computations B. Koren,∗ M. R. Lewis,∗,1 E. H. van Brummelen,∗,2 and B. van Leer†,1 ∗CWI, P.O. Box 94079, 1090 GB Amsterdam, The Netherlands; and †University of Michigan, Department of Aerospace Engineering, Ann Arbor, Michigan 48109-2140 E-mail: barry.koren@cwi.nl, mervyn.lewis@cwi.nl, e.h.vanbrummelen@lr.tudelft.nl, and br...