Investigation on temperature heterogeneity for angled placing of crates in a cold storage, during precooling

Abstract

Precooling conditions in cold storage are essential for preserving horticultural produce and reducing food and moisture loss. Inside a cold storage, the chilling rate and temperature heterogeneity are determined by the airflow. The majority-aligned stacking of produce in containers does not aid air mixing. This research examines how a minor angle between the placement of crates and the predominant air flow direction influences temperature heterogeneity and air velocity. A numerical model is developed to analyze the heat transfer and air flow distribution within cold storage, and it is validated using an experimental study with a normalized root mean square error of 4.57%. The validated model is used to investigate the impact of angular placement of containers and their potential benefits. As the angle of an inclination increases, the region of bypassing air decreases considerably, and the air remains in contact with the crates for a longer period. The monitored temperature distribution within the cold storage indicates that at 15° angle, the temperatures of the crates are approximately 9.89% lower than with a conventionally aligned crate arrangement. Calculations of temperature heterogeneity reveal that containers arranged at 15° were less susceptible to temperature heterogeneity. This research will help cold storage proprietors reduce the pull-down temperature and extend the shelf life of perishable goods.