Akademik Veri Yönetim Sistemi
HEAT AND MASS TRANSFER, cilt.46, sa.5, ss.555-562, 2010 (SCI-Expanded)
This paper presents an experimental and theoretical investigation of drying of moist slab, cylinder and spherical products to study dimensionless moisture content distributions and their comparisons. Experimental study includes the measurement of the moisture content distributions of slab and cylindrical carrot, slab and cylindrical pumpkin and spherical blueberry during drying at various temperatures (e.g., 30, 40, 50 and 60A degrees C) at specific constant velocity (U = 1 m/s) and the relative humidity phi = 30%. In theoretical analysis, two moisture transfer models are used to determine drying process parameters (e.g., drying coefficient and lag factor) and moisture transfer parameters (e.g., moisture diffusivity and moisture transfer coefficient), and to calculate the dimensionless moisture content distributions. The calculated results are then compared with the experimental moisture data. A considerably high agreement is obtained between the calculations and experimental measurements for the cases considered. The effective diffusivity values were evaluated between 0.741 x 10(-5) and 5.981 x 10(-5) m(2)/h for slab products, 0.818 x 10(-5) and 6.287 x 10(-5) m(2)/h for cylindrical products and 1.213 x 10(-7) and 7.589 x 10(-7) m(2)/h spherical products using the Model-I and 0.316 x 10(-5)-5.072 x 10(-5) m(2)/h for slab products, 0.580 x 10(-5)-9.587 x 10(-5) m(2)/h for cylindrical products and 1.408 x 10(-7)-13.913 x 10(-7) m(2)/h spherical products using the Model-II.