Discuss the following problem:
Q: Engine oil flows through a 25-mm-diameter tube at a rate of 0.5 kg/so The oil enters the tube at a temperature of 25°C, while the tube surface temperature is maintained at 100°C.
(a) Determine the oil outlet temperature for a 5-m and for a 100-m long tube. For each case, compare log mean temperature difference to the arithmetic mean temperature difference.
(b) For 5 < l="">< 100="" m,="" compute="" and="" plot="" the="" average="" nusselt="" number="" nu="" d="" and="" the="" oil="" outlet="" temperature="" as="" a="" function="" of="" l.="">