Ashell-and-tube heat exchanger is used for heating 15 kg/s of oil (cp = 2.0 kj/kg · k) from 20°c to 46°c. the heat exchanger has one shell pass and six tube passes. water enters the shell side at 85°c and leaves at 65°c. the overall heat transfer coefficient is estimated to be 1000 w/m2 · k. calculate the rate of heat transfer and the heat transfer area.

Consider a 1.2 meter high and 2 meter wide glass window whose thickness is 6 mm and thermal conductivity is 0.78 w/m °c. the room temperature is maintained at 24 °c, while the outdoor temperature is -5 °c. the convective heat transfer coefficients on the inner and outer surfaces of the window are 10 w/m2 °c and 25 w/m2 °c respectively. (a) draw the thermal resistance network, etermine the steady rate of heat transfer t e glass window (c) determine the temperature of the inner surface of the window