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An air cooled cylindrical wall is to be fitted with triangular fins of 3 cm thickness at base and 12 cm in height. The fins are made from stainless steel with density 8000 kg/m3 and thermal conductivity 17.5 W/m K. The wall temperature is 600 degree Celsius and the fin is exposed to an environment with t a = 30 degree Celsius and h = 20 W/m2 K. What is the temperature distribution along the fin? . b) t = 20 + 250 I 0 . c) t = 30 + 250 I 0 . d) t = 40 + 250 I 0 .

An air cooled cylindrical wall is to be fitted with triangular fins of 3 cm thickness at base and 12 cm in height. The fins are made from stainless steel with density 8000 kg/m3 and thermal conductivity 17.5 W/m K. The wall temperature is 600 degree Celsius and the fin is exposed to an environment with t a = 30 degree Celsius and h = 20 W/m2 K. What is the temperature distribution along the fin? . b) t = 20 + 250 I 0 . c) t = 30 + 250 I 0 . d) t = 40 + 250 I 0 . Correct Answer 6.056 (x) 1/2

α/α 0 = t – t 0/t 0 – t a = I 0 / I 0 . Here B = (2 h l/k δ) ½ = 3.028.

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