Consider the air cooling system and conditions of .31, but

Chapter 8, Problem 8.100

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Consider the air cooling system and conditions of 8.31, but with a prescribed pipe length ofL?15 m.(a) What is the air outlet temperature, Tm,o? What isthe fan power requirement?(b) The convection coefficient associated with airflowin the pipe may be increased twofold by insertinga coiled spring along the length of the pipe to disrupt flow conditions near the inner surface. Ifsuch a heat transfer enhancement scheme isadopted, what is the attendant value of Tm,o? Useof the insert would not come without a corre-sponding increase in the fan power requirement.What is the power requirement if the friction factor is increased by 50%?(c) After extended exposure to the water, a thin coat-ing of organic matter forms on the outer surface ofthe pipe, and its thermal resistance (for a unit areaof the outer surface) is Rt,o?0.050 m2?K/W. Whatis the corresponding value of Tm,owithout the insertof part (b)?