An uninsulated steam pipe with a wall temperature of 140 °C passes through a room of...

An uninsulated steam pipe with a wall temperature of 140 °C passes through a room of quiescent air of 14 °C. The pipe is horizontal and has an outer diameter of 20 cm. Find the following (include units if needed):

a) The temperature to evaluate properties = __________

b) The Rayleigh number, _____________

c) The heat transfer coefficient, h = ____________

d) q’ along the pipe = ________________

e) The pipe diameter is decreased by 50%. If all other parameters remain the same, will the heat transfer coefficient increase, decrease or stay the same? ___________. Justify your answer mathematically. For air: ν = 20.92 x 10-6 m2/s, α = 29.9 x 10-6 m2/s, 30 x 10-3 W/m·K, Pr = 0.7

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samet mamat answered 8 months ago

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