A three-dimensional numerical model of fluid flow, temperatureTemperature, and solidificationSolidification is developed to analyze the effect of a ruler electromagnetic brakeElectromagnetic brake (EMBr) over a single-phase flow of steelSteel in a CSP moldCSP mold using the enthalpy porosity method and the \(k - \varepsilon\) Realizable to account for the turbulent nature of the flow inside the mold. The model is partially validated by comparing the results of fluid flow, thermal behavior, and shell growth thickness against those reported in the literature. Then, a magnetohydrodynamicMagnetohydrodynamics model (MHD) was coupled to consider the effect of the EMBr over the molten steelSteel. The results show that the EMBr reduces the velocity of the molten steelSteel at the mold exit by ~ 55%. The EMBr also slightly increases the meniscus temperatureTemperature from \({1803}\) to \({1807}\;{\text{K}}\) , while producing only a minor reductionReduction in the solidified shellSolidified shell thickness (from 9.3334 to 9.2443 mm at mold exit).