［［Objective ］］ To improve the automation level of 0the temperature control of grain cooling.［［Methods ］］ Using SST k-ω turbulence model and non -equilibrium thermal model to conduct theoretical analysis.Fluent was used for simulation and combined with process validation to explore the temperature distribution law during the process of grain spreading and cooling,and to optimize the spreading and cooling process via Univariate analysis and multivariate orthogonal analysis.Based on the degree how the discharge temperature meets the process requirements,and analyzed the impact of the thickness of the grain layer,the speed of the plate chain movement,and the impact of the exhaust air volume on the air flow distribution,temperature field distribution,and the temperature changes during the entire grain movement process.［［Results］］ After analysis,it was found that the thickness of the material layer has significant impact on the discharge temperature,the speed of the plate chain movement and the exhaust air volume have secondary impacts.The relationship equations between the discharge temperature and the grain residue processing capacity,and exhaust air volume were determined,which were convenient for predicting the discharge temperature in case of process changes.［［Conclusion ］］ Through process verification,the non -equilibrium thermal simulation method is accurate and effective in simulating the spreading and cooling process.The optimal process conditions for this spreading and cooling machine are about 20 cm in thickness of grain,0.15 m/s in plate chain movement and 5 000 m3/h exhaust air volume.