Simulation of air-supply systems efficiency in refrigerated vehicles to prevent food spoilage

An improper air distribution within refrigerated truck chambers is the major cause of inadequate road transport of perishable products under controlled temperature. Inadequate temperature control permits microbial and/or enzymatic deterioration. Experimental results in refrigerated long road vehicles show temperatures differences in the cargo of as much as 12ºC. This paper presents a computational model to predict, and visualize, the temperature conditions (e.g. velocity, temperature and relative humidity) in refrigerated truck chambers. The model consists of a computer procedure, in which the general equations describing the airflow pattern and the heat/mass transfer in a refrigerated room are solved using the finite volume method. The effect of turbulence is described by the k-ε turbulence model. The computer model was experimental validated by measurements taken from a reduced-scale model designed to provide similarity with a prototype. The model was applied to calculate the indoor cold conditions provided by different types of air supply systems used in compartments of long road vehicles