Time i Unit vector tamgent to the control-volume surface u, V, w Velocity components in the x, y, and z coordinates, respectively U Velocity component in the direction of n (= K • n) V Volume V,-Median-dual control volume at a mesh point i 'Vceii Element control volimie Vn Overlapped control voltmie V Velocity vector Vn Velocity component normal to a surface Vt Velocity component tangent to a surface VNN Van Neumann nvimber X, y, z Cartesian coordinates Greek Symbols AQ At Time step Af.nt, Inviscid time step Atvis Viscous time step AXrm AYja Increments of x and y along the face m SW Characteristic variable set e Preconditioning scaling parameter Ci, £2 Empirically determined coefficients used in the dissipation terms of the central-difference-type discretization C3 Weighting parameter used in residucd-smoothing