Analysis of airflow and heat transfer inside fruit packed refrigerated shipping container: Part I - Model development and validation

- CFD was applied to develop a model of shipping container packed with fruit.
- The model incorporated the influence of wooden pallet base.
- Low airflow and high temperature regions were identified.
- The model showed good agreement with experimental results.

This paper developed and validated a computational fluid dynamic (CFD) model of airflow and produce cooling inside a fully loaded refrigerated shipping container (reefer) based on porous medium approach. Wind tunnel tests were used to obtain the pressure drop characteristics of palletized stack of apple fruit. Detailed structure of the T-bar floor of the reefer and resistance to airflow of wooden pallets were included in the model. Airflow and temperature data obtained from a fully loaded, full-scale reefer were used to validate the model. The model successfully reproduced the airflow and temperature profiles inside the reefer, and in addition, high and low cooling regions were identified. At 24 h, the average temperature inside the reefer reached 2.7 °C (exp.) and 2.8 °C (numerical) from an initial 9.5 °C with an overall standard deviation of 1.70 °C (exp.) and 2.32 °C (numerical). Model predictions were acceptably accurate with an average error of 26 and 18% in predicting airflow and temperature, respectively. The absence of vent-hole on the bottom face of the packaging box caused non-uniform airflow and a highly heterogeneous cooling. These demonstrated the importance of packaging design that take into account the airflow path inside reefers.