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Problem 3: (35pts) Atmospheric air enters the heated section of a circular tube at a flow rate of 0.005 kg/s and a temperature of 30°C. The tube is of diameter D =60mm, and fully developed conditions with h = 30W/m2K exist over the entire length of L-4m. Take cp-1015 /kg.K 2 (a) (10pts) For the case of uniform surface heat flux at q-1000W/m, determine the total heat transfer rate q and the mean temperature of the air leaving the tube Tm,o (b) (10pts) What is the value of the surface temperature at the tube inlet Ts,jand outlet Ts,o? (c) (10pts) If the surface heat flux varies linearly with x such that q(W/m2) 480x(m), what are the values of q, m,or Ts,i and T? S,o (d) (5pts) For each type of heating process, what heat fluxes are required to achieve an air outlet temperature of 130°C?

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