In order to prevent the spontaneous combustion of residual coal

based on predecessors′research results and combined with the relative theories

the method of periodically transforming the direction of ventilation was presented

and its principle to prevent the spontaneous combustion of residual coal was analyzed.The Fluent software was used to carry out numerical simulation of concentration field

temperature field and the configuration of oxidation zone under the condition of periodically transforming the direction of ventilation.The numerical simulation results show that concentration field

temperature field and the configuration of oxidation zone will be changed when the direction of ventilation is transformed

and it is proved to be feasible that the method of periodically transforming the direction of ventilation is used to prevent the spontaneous combustion of residual coal.According to the analysis of data

the application conditions of the method and the period of transforming the direction of ventilation are connected with the spontaneous combustion period of residual coal;the rate of temperature increase can be slowed down through the method of periodically transforming the direction of ventilation

and it further proves that the method is feasible;attention must be given to the concentration of harmful gas in return airway and the explosion of harmful gas in goaf when the method of periodically transforming the direction of ventilation is applied.