In order to understand the temperature dynamic feature of open coal pile, the 2D Heat and mass transfer mathematical model of coal pile was established under the condition of driving force of air pressure, thermal pressure and mass diffusion. Then the fluent software was used to analyze the seveal field informations such as airleakage, oxygen concentration and temperature. The results show that the high temperature region always lies in windward slope where has appropriate air velocity and sufficient oxygen supply. And it's all because the coal pile has the environment characteristic which is that windward slope has the highest air velocity and oxygen supply, which decreases along as distance from windward slope, and leeward slope is the opposite. Air velocity and porosity impact the heating up rate mostly then windward slope angle, and environment temperature has least effect for this. Favourable comparisons between numerical and experimental results justify the suitability of the numerical approach. Hence the fire source position can be decided roughly by numerical results to narrow the detection range, consequently, the efficience of fire protection will improve for timely measurement.