A duct that is 2 ft by 5 ft in crosssection and 80 ft long c

A duct that is 2 ft by 5 ft in cross-section and 80 ft long carries conditioned air through the space above the hung ceiling in an office building. The air enters the duct from the air handler at 55 F with a flow rate of 8,000 cfm. The difference in pressure between input and output of the duct is 2 in. water. The temperature in the space is 85 F. Determine The thickness of insulation needed on the sides of the duct to have a temperature rise of 1 F, if k_ins = 0.025 Btu/hr-ft-F and h_combined = 1.47 Btu/hr-ft^2-F The drop in sensible cooling capacity due to the heat transfer to the air flow. The leakage flow rate from the duct. The total drop in capacity due to leakage and heat loss in energy and relative to the total capacity.

Solution

The answer of following question is .

The thickness of insulationis .035mm

The drop insensible cooling is 345 kj.