äbäi 33Q2: An industrial freezer isdesigned to operate with aninternal air temperature of -20oC when the external airtemperature is 250C and theinternal and external heattransfer coefficients are 12W/m2 K and 8 W/m2 K,respectively. The walls of thefreezer are compositeconstruction, comprising of aninner layer of plastic (k = 1 W/mK, and thickness of 3 mm), andan outer layer of stainless steel(k = 16 W/m K, and thickness of1 mm). Sandwiched betweenthese two layers is a layer ofinsulation material with k = 0.07W/m K. Find the width of theinsulation that is required toreduce the convective heat* loss to 15 W/m2

Concept used: Heat transfer coefficient is net heat loss per unit change in temperature.

Answered: Q2: An industrial freezer is designed…

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