Optimizing cold storage for uniform airflow and temperature distribution in apple preservation using CFD simulation.

Area of Science:

• Agricultural Engineering
• Food Science
• Thermal Engineering

Background:

• Apples require precise cold storage conditions to maintain quality and prevent spoilage.
• Standard crate stacking aims for adequate air circulation but can lead to uneven cooling.
• Optimizing airflow is crucial for efficient cold storage and product longevity.

Purpose of the Study:

• To develop and validate a computational fluid dynamics (CFD) model for apple cold storage.
• To investigate the impact of alternate crate stacking arrangements on airflow and temperature distribution.
• To identify optimal stacking strategies for enhanced cooling efficiency and reduced temperature heterogeneity.

Main Methods:

• A CFD model was created for a cold room containing apple-filled crates, treating crates as porous media.
• The model was validated against experimental data for a conventional stacking arrangement (CS1), achieving a root mean square error of 1.13°C.
• Two additional stacking configurations (CS2 and CS3) with varied spacing and orientations were simulated.

Main Results:

• The CS3 configuration, with increased z-direction spacing, demonstrated a 7.4% and 3.7% higher average air velocity than CS2 and CS1, respectively.
• CS3 improved the cooling rate by 25.2% and increased the number of chilled crates by 20% within 40 hours.
• Temperature heterogeneity was reduced to 3.59°C in the CS3 configuration, indicating more uniform cooling.

Conclusions:

• Alternate crate stacking significantly impacts airflow and temperature distribution in apple cold storage.
• The CS3 arrangement, featuring greater spacing, offers superior cooling performance and uniformity.
• The developed CFD model can predict hot spots and guide optimal stacking strategies for improved cold chain management.