Steam in the condenser of a steam power plant is to be condensed at a temperature of 60°C ($h_{fg} = 2395$ kJ/kg) with cooling water ($C_p = 4180$ J/kg°C) from a nearby river, which enters the tubes of the condenser at 15°C and leaves at 32°C. The tubes of the condenser are thin-walled and have a diameter of 0.6 cm. If the internal and external heat transfer coefficients are given as $h_i = 5200$ W/m²°C and $h_o = 4450$ W/m²°C,
a. By neglecting the thickness of the tubes, calculate the overall heat transfer coefficient (U).
b. If the surface area of the tubes is 58 m², determine the mass flow rate of the cooling water needed and the rate of condensation of the steam in the condenser.
c. Determine the total length of the tubes.
