The left face of a one dimensional slab of thickness 0.2 m is maintained at 80°C and the right face is exposed to air at 30°C. The thermal conductivity of the slab is 1.2 W/m.K and the heat transfer co-efficient from the right face is 10 W/m2.K. At steady state, the temperature of the right face in °C is____________________?
Correct answer: D. 48.7
- A. 77.2
- B. 71.2
- C. 63.8
- D. 48.7
Explanation
The conduction and convection resistances are 0.2/1.2 and 1/10 m²·K/W, respectively. Thus the heat flux is 187.5 W/m² and the air-side temperature drop is 18.75°C, giving a right-face temperature of about 48.7°C.
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