Analysis of an internal structure for refrigerated container: Improving distribution of cooling capacity

Abstract

An improved internal structure is proposed to improve the distribution of cooling capacity in refrigerated container. Firstly, a computational fluid dynamics model was established and the fruit stacks was simplified to be porous medium. The flow resistance coefficient was obtained by combining theory and numerical simulation and then verified. Secondly, three baffles were added to reduce the loss of cold airflow by blocking the airflow through air-gaps. The velocity and temperature of the previous refrigerated container and the improved refrigerated container were obtained and compared. The cold airflow distribution in the improved refrigerated container is more uniform. The improvement of vertical velocity in all stacks is in the range of 5.24% – 425.04%. The cooling performance of the two refrigerated containers were also obtained. The variation of temperature distribution is within ±1 °C and the cooling time is also reduced by at least 22.9% in the improved refrigerated container. Finally, the proposed structure showed good applicability for different fruits and vegetables. For all produce tested, the decrease ratio of temperature rise in the improved refrigerated container relative to the previous refrigerated container ranges from 34.0% to 59.5%.