화학공학소재연구정보센터
Chemical Engineering Communications, Vol.189, No.10, 1437-1445, 2002
Artificial intelligence control of food freezer using rotating disk air distributor for uniform freezing
A rotating disk air distribution (RDAD) system consisting of a rotating disk with an air supply hole was fabricated to solve the nonuniform freezing problem of a freezer that supplies air through a duct at a fixed location. The RDAD system was installed in a freezer to supply freezing air in various directions by controlling the position of the air supply hole. An equation estimating air velocity in the freezer was developed based on heat balance between a brass block thermocouple (BBT) probe and ambient air stream. The equation was applied to the analysis of airflow patterns developed through the RDAD and the fixed duct system. For control of the RDAD system, a fuzzy matrix was constructed with the measured nodal temperature at 3D locations in the freezer and used to search for the optimum direction of air supply. Uniform cooling was accomplished with the RDAD system using fuzzy and expert algorithms leading to temperature deviation sigma=0.666, compared with 0.289 of the fixed air supply system. Cooling rate of model food (BBT) was 1.75 times faster than that of the fixed system.