The consistency of temperature and grain size is crucial to the quality of the continuous casting slab. In order to study the temperature and grain size of the continuous casting slab as influenced by the cooling spray state, a cellular automatic finite element (CAFE) coupled model was developed. The model was validated by low magnification inspection and infrared temperature measurement. The process of continuous casting was simulated by numerical model. Temperature and grain size distribution in the transverse direction of the continuous casting slab can be controlled by adjusting the nozzle arrangement. The effect of different nozzle positions on the temperature field distribution in the second cooling zone of continuous casting was simulated. The optimal nozzle position was selected with the temperature distribution uniformity as the important index. When the optimized nozzle arrangement is selected, the transverse temperature and grain size of the continuous casting slab are more uniform.

A cellular automaton finite‐element coupling model is developed to investigate the influences of the solidification structure of a continuous casting slab by the state of the cooling spray and process conditions. The model is validated. The solidification structure is simulated for different cooling spray schemes, superheat degrees, and casting speeds. The grain growth and distribution of the continuous casting slab near the corner area are sensitive to the cooling spray. As the distance of the nozzle from the surface of the continuous casting slab increases, the radii of the columnar and equiaxed grains tend to increase near the corners. The distribution of a columnar‐to‐equiaxed grain transition near the corner area gradually moves toward the core of the slab as the distance of the nozzle from the continuous casting slab decreases. At a casting speed of 1.2 m min−1 and superheat degree of 20 °C, the best nozzle height from the surface of the continuous casting billet is 234.5 mm. The casting speed and superheat significantly affect the grain radius. With the increase in the casting speed and decrease in the degree of superheat, the average grain radius decreases, while the equiaxed grain area increases.