Sample problem 15.2 A conveyor drier (Section 15.2.1) is required to dry peas from an initial moisture content of 78% to 16% moisture (wet-weight basis), in a bed 10 cm deep which has voidage of 0.4. Air at 85°C with a relative humidity of 10% is blown perpendicularly through the bed at 0.9 ms. The drier belt measures 0.75 m wide and 4m long Assuming that drying takes place from the entire surface of the peas and there is ne shrinkage, calculate the drying time and energy consumption in both the constant- and the falling-rate periods. (Additional data: the equilibrium moisture content of the pea is 9%, the critical moisture content 300% (dry-weight basis), the average diamete 6 mm, the bulk density 610 kg m, the latent heat of evaporation 2300 kJ kg, the saturated water vapour pressure at wet-bulb temperature 61.5 Torr and the mas transfer coefficient 0.015 kg m2

Sample problem 15.2 A conveyor drier (Section 15.2.1) is required to dry peas from an initial moisture content of 78% to 16% moisture (wet-weight basis), in a bed 10 cm deep which has voidage of 0.4. Air at 85°C with a relative humidity of 10% is blown perpendicularly through the bed at 0.9 ms. The drier belt measures 0.75 m wide and 4m long Assuming that drying takes place from the entire surface of the peas and there is ne shrinkage, calculate the drying time and energy consumption in both the constant- and the falling-rate periods. (Additional data: the equilibrium moisture content of the pea is 9%, the critical moisture content 300% (dry-weight basis), the average diamete 6 mm, the bulk density 610 kg m, the latent heat of evaporation 2300 kJ kg, the saturated water vapour pressure at wet-bulb temperature 61.5 Torr and the mas transfer coefficient 0.015 kg m2

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.54P

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