大跨度高大平房仓粮堆热湿传递过程的 数值模拟及试验.

In view of the problems of large temperature stratification and uneven cooling of grain piles in large warehouses, this paper is based on the theory of heat and mass transfer in porous media grain piles. This study incorporates methods from computational fluid dynamics coupled with the physics of heat transfer, fluid and moisture transport. A mathematical physical model for heat and moisture transfer in grain piles is established. The ventilation experiment of the one-story warehouse is simulated. The results from the experimental data and the results from the numerical simulations are compared. The temperature and moisture changes during actual ventilation and numerical simulation ventilation were explored. The results show that the model can predict the changes of airflow velocity, temperature and relative humidity inside the grain pile; when the initial average temperature of the grain pile is the same. When the inlet air temperature is increased from-17 ℃ to-4 ℃,the ventilation time is extended from 37 h to 108 h. When the speed is increased from 0.24 m/s to 0.31 m/s, the ventilation time is shortened from 228 h to 176 h. Changing the inlet air temperature or outlet wind speed will affect the required ventilation time. Economical ventilation time can be obtained by establishing the relationship between inlet air temperature and apparent wind speed, and outlet air speed and apparent wind speed. The fan with reasonable power can be selected based on this. Provide a reference for the ventilation operation of grain piles. [ABSTRACT FROM AUTHOR]