Consider a heat exchanger with square tube of dimensions 0.05 m X 0.05 m inside a circular tube of diameter 0.10 meters. Oil at inlet temperature of 350 C and average velocity of 1 m/s flows inside the square tube and is cooled down to 200 C by water flowing in the annular region at an average velocity of 0.5 m/s and inlet temperature of 25 C.
a) Determine the mass flow rates of cold and hot fluids.
b) Determine the heat transfer rate
c) Determine the exit temperature of the cooling water.
For water: ? = 1000 kg/m^3 ; Cp = 4180 J/kg*K
For oil: ? = 855 kg/m^3 ; Cp = 2130 J/kg*K