Numerical simulation on temperature field effect of stack method of garden stuff for fresh-keeping transportation

Temperature field is one of the factors to guarantee the quality of cargoes under fresh-keeping transportation. In order to investigate the temperature field distributions, the differential pressure experimental container with banana cargoes units was used as the research object, a 3d numerical calculated model of 1/4 dimension of the car body was built by using the porous model, SIMPLE algorithm and wall function method to simulated the three kinds of garden stuff stack methods, including the "blanks on both two sides and middle", "blanks on both sides" and "full load". The cloud charts of the temperature distributions on the symmetry sections in the container and on the surface of cargoes were obtained. Comparative analyses show that rational stack method can improve the distribution of temperature field and under "blanks on both two sides and middle" stack method, the heat exchange of the cold air and goods is better, and the temperature field ahead of container is more uniform compared to the "blanks on both sides" and "full load". Experimental results meet the simulation results well，where the deviation between simulation temperature and the average of test values is no more than 1.5℃. This study reveals the general rules of the temperature field in fresh-keeping transportation with controlled atmosphere, which can provide a reference for the optimization design and selection of reasonable stack methods in fresh-keeping transportation.