A cylindrical rod of 4.0 cm diameter, 50 cm length, and 65 Wm 'K' thermal conductivity...

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A cylindrical rod of 4.0 cm diameter, 50 cm length, and 65 Wm 'K' thermal conductivity is welded normal to the outside wall of a combustion chamber as a hanger for instrument cables. The rod is exposed to 25C air with a convective heat transfer coefficient of 15 WmK. The steady-state wall temperature is 200C. a. What is the rate of heat loss from the rod? Estimate the temperature at the tip of the rod. b. The wall is covered with a 30-cm-thick layer of insulation and the same rod protrudes normally outside the insulation layer. The portion of the rod inside the insulation layer may be considered perfectly insulated on its surface so that heat transfer within the insulated section of the rod can be considered to be one-dimensional (i.e. axial conduction). The temperature of the exposed section of the rod (outside the insulation layer) must be kept below 100C everywhere to avoid damaging the instrument cables hanging on the rod. Does the 50-cm-long rod meet this specification? c. If a tube with the same outside diameter and wall thickness of 3.0 mm were used instead of the rod, would it meet the specified operating limit? The air within the tube can be considered to be a perfect insulator. A cylindrical rod of 4.0 cm diameter, 50 cm length, and 65 Wm 'K' thermal conductivity is welded normal to the outside wall of a combustion chamber as a hanger for instrument cables. The rod is exposed to 25C air with a convective heat transfer coefficient of 15 WmK. The steady-state wall temperature is 200C. a. What is the rate of heat loss from the rod? Estimate the temperature at the tip of the rod. b. The wall is covered with a 30-cm-thick layer of insulation and the same rod protrudes normally outside the insulation layer. The portion of the rod inside the insulation layer may be considered perfectly insulated on its surface so that heat transfer within the insulated section of the rod can be considered to be one-dimensional (i.e. axial conduction). The temperature of the exposed section of the rod (outside the insulation layer) must be kept below 100C everywhere to avoid damaging the instrument cables hanging on the rod. Does the 50-cm-long rod meet this specification? c. If a tube with the same outside diameter and wall thickness of 3.0 mm were used instead of the rod, would it meet the specified operating limit? The air within the tube can be considered to be a perfect insulator.