Question

I. Design of Fins (35 pt). A stripping process produces a hot fluid (80°C) that flows inside copper pipe of 20 cm diameter (the thickness of the pipe wall is negligible). Outside the pipe, there is air flow at ambient temperature (20 °C). In order to recirculate the fluid produced, it is necessary to cool it down. This can be achieved by installing ten circular fins per meter of pipe (see figure below). These fins have a thickness of 0.1 cm (2) and a radius () of 20 cm a ) Draw the schematic of the resistance model with analog to the electrical circuit, identifying the heat transfer mechanisms (5 pt) 2) Calculate the fin efficiency (15 pt) 3) Calculate the amount of heat removed per meter (15 pt) The convective heat transfer coefficient inside the pipe is 250 W/m2 K, and 15 W/m2 K outside the pipe Note: In order to determine the thermal conductivity of the copper pipe, please assume temperature conditions of 100 °C FL

Answer 1

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AL + Ab 2 77 At 10x 1896.57+6219.2 At= 1896-87 cu 2 =25182-9 em CH-NE) : 27A A b e 1o(to0- toxo1) A 2x 7 X Ab 6217.2 un -(10 1896 S7 rs x/25182.9 25182.9 (04 8-960 87IO 2818-2-9 (8 88.67 W mela = 18.39-694 Amount of Neet