A 50-mm-thick air gap separates two horizontal metal plates that form the top surface of an industrial furnace. The bottom plate is at
(a) Determine the convective heat flux across the gap when no insulation is in place.
(b) Determine the minimum number of foil sheets that must be inserted in the gap to eliminate free convection.
(c) Determine the conduction heat flux across the air gap with the foil sheets in place.
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Fundamentals of Heat and Mass Transfer
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