Optimisation of the refrigerating system for cheese processing requires an accurate prediction of chillingtime, product temperature distributions and heat flow. Many existing CFD models can provide the bestpredictions by directly solving the three-dimensional heat transfer problem within the product and for airflow around the product; however, they are time-consuming and not suitable for routine use. Aone-dimensional numerical solution proposed by Ghraizi, Chumak, Onistchenko, and Terziev (1996) hasbeen used to provide the quick answer to food processing engineers with a good accuracy. In this method,the partial differential equation describing one-dimensional non-linear unsteady heat conduction inside theproduct has been solved by a finite difference technique. The method can take into account thetemperature-dependence of thermal properties of foods and a general shape factor was used to reflect theproduct geometry. The model was applied to a single block of cheese, and agar. Predicted results arecompared to experimentally-measured temperature profiles as well as to results generated by the FoodProduct Modeller, FPM, software.
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