A numerical evaluation of adaptive on-off cooling strategies for energy savings during long-term storage of apples

摘要

Highlights?A transient CFD model is developed to analyse temperature dynamics in a coolstore.?Effects of cooling control on quality change and energy consumption are calculated.?Temperature fluctuations are largest near the edges of the fruit stack.?Temperature heterogeneity causes product quality change heterogeneity in the stack.?A larger on-off cooling differential for the same setpoint consumes more energy.AbstractThe main energy costs of long-term apple storage are associated with cooling. Reducing these costs without compromising product quality may be possible with minor room temperature increases. This paper presents a transient CFD model to evaluate automatic on-off cooling control based on different temperature differentials (0.4, 0.5 and 0.7?°C around a setpoint). Effects on temperature uniformity, quality changes and energy consumption during long-term storage of apples were calculated. A model for apple firmness change kinetics was coupled to the CFD model and applied to calculate changes in quality uniformity in a coolstore affected by spatiotemporal fluctuations in temperature. Large temperature fluctuations were observed near the outer edges of the stack and were more pronounced with a higher cooling differential. Using a small cooling differential around the setpoint temperature showed a better overall performance in terms of energy consumption and final product quality.]]>