This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. 0Analysis of the spatiotemporal temperature fluctuations inside an apple cool store in response to energy use concerns Alemayehu Ambaw (a, c) , Niels Bessemans (a) , Willem Gruyters (a) , Sunny George Gwanpua (a) , Ann Schenk (b) , Ans De Roeck (b) , Mulugeta A. Delele (a) , Pieter Verboven (a) , Bart M. Nicolai  It has been demonstrated that fan and refrigeration cycling works to save energy. Load shifting of controlled atmosphere stores for saving energy costs seems worthwhile. AbstractEnergy cost concerns have led to question the temperature and air flow regimes in cool store facilities. In this paper, a CFD model of the air flow and temperature dynamics inside an apple fruit Page 1 of 33 1 cool store was developed, validated and used to analyse energy cost saving alternatives. Load shifting was attempted by cycling the temperature set point between 1.2 °C and 0.6 °C following a day/night regime. Discontinuous use of the cooling operation, including 12 h on / 12 h off; 10 h on / 14 h off; and 8 h on / 16 h off were also investigated. The study showed that the air circulation fan is the major source of heat load. Hence, an attempt to reduce energy cost should first deliberate on reducing the fan operation time. The study developed a generic tool to analyse temperature control options inside an apple cool store in response to energy use concerns.

This study presents a novel methodology to model the cooling processes of horticultural produce using realistic product shapes rather than commonly-used simplified 3D shapes, such as spheres. Variable 3D apple and pear models were created by means of a validated geometric model generator based on X-ray computed tomography images. The fruit were randomly stacked into a geometrical model of a corrugated fibreboard box using the Discrete Element Method. A forced-air cooling process was simulated for three such apple filling patterns using CFD and the results were compared to those obtained with fruit represented by equivalent spheres. No significant difference in average aerodynamic resistance between the real apple shape and its spherical representation was found. The main contributor to the overall pressure drop was the package design rather than product shape. However, large differences in local air velocity and convective heat transfer coefficients were found between the two representations. The degree of cooling uniformity between individual fruit was overestimated when using simplified product shapes: real apple fruit shapes cooled less uniform. This difference between real and simplified product shapes was even larger for a box filled with pear fruit that are more different from a spherical shape. These results

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The 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