Optimization of Box Design of Storage Boxes in Cold Stores using CFD Analysis

Abstract

Food wastage due to inefficient storage techniques is not only adding to the food insecurity of the world but also causing an increase in the carbon footprint of the human race. If stored in an efficient way using optimized storage boxes, food wastage can be lowered significantly which can help reduce the ongoing energy crisis and achieve sustainable development. For stored fruits or vegetables, ventilation must be in such a way that temperature and humidity are homogeneous throughout the box and every single piece gets its fair share of fresh air which can be achieved by changing the design of vent holes. The results obtained from the computational fluid dynamic analysis of the standard R box used for fruit storage have proven that the box design that has been used by the storage industry for decades does not allow thermal uniformity which causes the rotting of food. The diameter and coordinates of vent holes can be tweaked in such a way that airflow through the storage boxes becomes more streamlined allowing every single product to dissipate its energy emanating from the process of respiration and change of temperature. Previous researchers have provided with alternate designs to standard R box but these designs are very limited in number. Moreover, the utilization of the design of experiments technique has not been previously explored, highlighting a significant research gap addressed in this study. In this research CFD analysis and design of experiments have been used to judge the performance of forty different fruit boxes. With the help of transient three-dimensional analysis, cooling of fruits placed in different boxes has been carried out and the variance of the plane cutting through the middle of fruit pieces has been calculated along with the overall temperature drop of fruit pieces. x The best-performing design has a variance of temperature on the mid-section plane of 6.28 K2 as compared to 7.43 K2 for the Standard R box which means a 16 % increase in homogeneity. Also, the temperature drop of fruit increased from 1.916 K in standard R to 2.7 K in design number 05 which is a 34 % increase resulting in energy conservation. In short, the design of fruit boxes can be improved with the tools like CFD and DoE by changing the coordinates, shape and dimensions of vent holes as was done with design number 05 ultimately leading to uniform temperature distribution