The fluid field in mould for slab concasting has been simulated using K-e double equation model i.e. the turbulent flow pulse kinetic energy k equation and the turbulent flow pulse kinetic scattering loss rate e equation in given numerical calculation conditions by three dimensional mathematical software Fluent. The basic characteristic of fluid field in mould was that there was a horizontal flow at exit of mould

which formed return flow as it impacted the wall of mould to divide the fluid in mould into up return flow and down flow. It is obtained by calculation that the immersion depth of nozzle for mould of 1250 mm x 200 mm slab 175 mm

the exit angle 16° ~ 18° and the casting speed 1.0 ~ 1.2 m/min are available for slab casting.