Consider two long, slender rods of the same diameter but different materials. One end of each rod is attached to a base surface maintained at 100°C, while the sur- faces of the rods are exposed to ambient air at 20°C. By traversing the length of each rod with a thermocou- ple, it was observed that the temperatures of the rods were equal at the positions XA = 0.15 m and x³ = 0.075 m, where x is measured from the base surface. If the thermal conductivity of rod A is known to be kA = 70 W/mK, determine the value of kB for rod B. XA=0.15m T-100°C- f -TA=TB XB=0.075m Rod A, KA=70W/m-K Too=20°C -Rod B, kB

Consider two long, slender rods of the same diameter but different materials. One end of each rod is attached to a base surface maintained at 100°C, while the sur- faces of the rods are exposed to ambient air at 20°C. By traversing the length of each rod with a thermocou- ple, it was observed that the temperatures of the rods were equal at the positions XA = 0.15 m and x³ = 0.075 m, where x is measured from the base surface. If the thermal conductivity of rod A is known to be kA = 70 W/mK, determine the value of kB for rod B. XA=0.15m T-100°C- f -TA=TB XB=0.075m Rod A, KA=70W/m-K Too=20°C -Rod B, kB

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.25P

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based on the information given here. Steam in a heating system flows through tubes whose outer diameter is 5-cm and whose walls are maintained at a temperature of 180°C. Circular aluminum alloy 2024-T6 fins [k = 186-W/m°C] of outer diameter 6-cm and constant thickness 1-mm are attached to the tube with the space between the fins 4-mm. The efficiency of these fins is 0.97 and the surface area of a single fin is 0.001916 m2. Heat is transferred to the surrounding air at 25°C, with a heat transfer coefficient of 40-W/m2°C. The total heat transfer from the finned tube per meter length in W is approximately 1910 3080 cannot be determined 2495
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