A pipe is insulated to reduce the heat loss from it. However, measurements indicate that the rate of heat loss has increased instead of decreasing. Can the measurements be right?

(a) What is the rate of energy loss in watts per square meter through a glass window 3.5 mm thick if the outside temperature is -17°F and the inside temperature is +73°F? (b) A storm window having the same thickness of glass is installed parallel to the first window, with an air gap of 5.5 cm between the two windows. What now is the rate of energy loss if conduction is the only important energy-loss mechanism? (The thermal conductivity of window glass is 1.0 W/m-K, and of air is 0.026 W/m-K.) (a) Number (b) Number Units Units

(a) What is the rate of energy loss in watts per square meter through a glass window 2.4 mm thick if the outside temperature is -5.1°F and the inside temperature is +70°F? (b) A storm window having the same thickness of glass is installed parallel to the first window, with an air gap of 5.9 cm between the two windows. What now is the rate of energy loss if conduction is the only important energy-loss mechanism? (The thermal conductivity of window glass is 1.0 W/m-K, and of air is 0.026 W/m.K.) (a) Number i (b) Number Units Units

temperature is 330 K. Find the heat loss per unit area and the temperature of the junction of the fire brick and insulating brick? RO 5. In Sohar Petroleum Company, a steam pipeline, with 150 mm ID and 160 mm OD carries steam. The pipeline is surrounded with a layer of heat insulating material (K=0.08 W/m.k) of thickness 100 mm. The temperature drops from 392.8 K to 313 K across the insulating surface. Determine the rate of heat loss per 1 m length of pipe line. ID = 1Somm 160 mm OD,h-loo mm .K=0.08w/m.k %3D 「-392.8 ん/ 12 = 313k = 313 K 2.