A vertical twin-roll continuous thin-strip casting process for stainless steel has been mathematically modeled. The model takes into account the coupled turbulent flow, heat transfer, and macroscopic solidification aspects of the process. A low-Reynolds-number K-ε turbulence model was used to account for the turbulent effects. The transport equations for the wedge-shaped caster's cavity were solved using a boundary-fitted nanorthogonal coordinate system. A control-volume-based, iterative finite difference scheme on a staggered grid was used to solve the discretized transformed equations. The SIMPLE algorithm was employed to resolve the velocity-pressure coupling in the momentum equations. The parameters examined in this study include the Darcy coefficient and turbulent damping factor for the mushy region, the roll gap, and the inlet nozzle width. The effects of these process parameters on the turbulent flow and temperature fields, the turbulent eddy viscosity distributions, and the extents of the mushy and solidified regions were ascertained. A change of the Darcy coefficient above 800 did not show any significant effect on the results. The three types of liquid-fraction-dependent turbulent damping factor used for modeling the mushy region did not show a measurable effect on the solidified shell thickness but showed a noticeable influence on the velocity and temperature distributions in both liquid and mushy regions. For a fixed width of the nozzle, an increase in the roll gap increased the penetration depth of the plunging inlet jet but decreased the extent of the mushy region. The solidified shell profile was insensitive to the change of the roll gap. For a fixed roll gap, an increase in the width of the nozzle decreased the penetration depth of the nozzle but increased the extent of the mushy region, while the solidified shell thickness remained practically unaffected.