A k-ω turbulence model by Wilcox is applied to cascade flow calculations. A staggered finite volume scheme is proposed to solve the compressible Reynolds-averaged Navier-Stokes equations and the k-ω equations are solved on staggered control volumes with k and ω defined at the cell vertices of the original grid. By use of this combination of the cell-centered and cell-vertex schemes, the method maintains a small stencil for all diffusion terms and closely couples the Navier-Stokes and k-ω equations