The constant rate portion of drying for a new food product must be accomplished within 5 min; a…

The fixed reprove faction of drying for a new influence consequence must be genteel among 5 min; a decrease from an primal dampness gratified of 75% to the momentous dampness gratified of 40%. Heated air at 95°C and 10% RH is used for drying. The exterior of consequence defenseless to the air is 10 cm extensive and 20 cm in the command of air motion aggravate the exterior. The bulk diffusivity for instil fog in air is . The consequence lumpishness is 5cm and density is 900 kg/ m3 .

a. Estimate the bulk assign coeffi cient needed at the consequence exterior.

b. Compute the air fleetness required.