One hundred pounds of carbon dioxide is stored in a high-pressure cylinder 10 in. in diameter (OD), 4 ft long and 1/2 in. thick. The cylinder is fitted with a safety rupture diaphragm designed to fail at 2000 psig (with the specified charge, this pressure will be reached when the temperature increases to 120?F). During a fire, the cylinder is completely exposed to the irradiation from flames at 2000?F (ε = 1.0). For the specified conditions, c = 0.60 Btu/(lb ?F) for CO2. Neglecting the convective heat transfer, determine the time the cylinder may be exposed to this irradiation before the diaphragm will fail if the initial temperature is 70?F and(a) The cylinder is bare oxidized steel (ε = 0.79),(b) The cylinder is painted with aluminum paint (ε = 0.30).GIVENCO2 in a high pressure cylinder exposed to flamesMass of CO2 (mg) = 100 lbsCylinder dimensionsOutside Diameter (D) = 10 in = 5/6 ftLength (L) = 4 ftThickness (s) = 1/2 in = 1/24 ftRupture diaphragm fails at 2000 psig (Tgf = 120?F = 580 R)Temperature of flames (Tf) = 2000?F = 2460 R (εf = 1.0)Specific heat of CO2 (cv) = 0.60 Btu/(lb ?F)Initial temperature (Tgf) = 70?F = 530 RASSUMPTIONSConvective heat transfer is negligibleCylinder is 1% carbon steelIrradiation is constant and uniform over the entire cylinderQuasi-steady stateThermal resistance between the gas and the cylinder is negligible (Ts = Tg)Variation of specific heat of gas and cylinder with temperature isnegligible

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Surrounded By Flames D- 10 In T= 2460 R L-4 ft