Experimental Study and Simulation of Radiation Frost using Computational Fluid Dynamics

Frostbite is one of the most important reasons for crop loss in Iran. Radiation frost due to inversion condition causes temperature drop below critical damage point which leads to extracellular ice formation inside the plant tissues. The purpose of this study was to identify the most important factors affecting radiation freezing. A region near the city of Shiraz with a chance of happening frostbite, according to previous weather reports, was selected. The temperature and wind speed were measured at the field level in the first and second half of the year, in nights expecting frostbite could be occurred. Then, the CFD simulation of heat transfer and thermal distribution was carried out using the FLUENT software, based on the time and the height of the ground surface under unstable conditions during frostbite. The numerical model was studied based on the data which obtained from the field stand. The results showed a good correlation between empirical and analytical data, so that the estimation by the root means square error method, 0.99, was obtained for experimental and simulation temperature values. Also, the results illustrated the wind blowing had a significant effect on preventing a sudden drop in temperature and frosting of products take place.