Thermal analysis of a cold room

The purpose of this research was to study the storage of fresh raw horticultural material processed and frozen in an industrial plant in southern Italy. A simulation technique (validated by experimental tests) was used giving the chance to evaluate the effect of bins location on the cooling capacity of the cold room avoiding expensive experimental tests. An external cooling system and an intermediate fluid ensure the cooling of the products. The air is distributed inside the cold room by two blowers that provide the forced convection of the air itself. First of all, experimental tests were carried out to validate the preliminary results obtained from the previous experiment, and then the authors carried out a computational fluid dynamic (CFD) analysis in order to verify where a good arrangement of the storage bins is achieved inside the room. The tests were carried out in summer (July) on zucchini and peppers. The important deviations in the temperature of the product are mainly due to the different position occupied by the bins in the room. In fact, they are positioned at different distances and heights from the forced convection fans. Both simulation and experimental results show that the raw material cooled in the shortest possible time was the one placed to the shortest distance from the wall and at the lowest height of the room because of the low heat transfer through the floor. By increasing the distance from the access door through which the most significant heat transfer takes place, there is a small variation due to the optimal position of the storage bins inside the room, which still allows a good distribution of air.