The condenser of a large thermal power plant is a body-tube type heat exchanger consisting of a single body and 30000 pipes with two passes each. The pipes are thin-walled with an inner diameter of 25...

The condenser of a large thermal power plant is a body-tube type heat exchanger consisting of a single body and 30000 pipes with two passes each. The pipes are thin-walled with an inner diameter of 25 mm, and steam condenses on the outer surfaces of the pipes with a convection coefficient of 11000 W / m2.K. The heat transfer required by the heat exchanger is 2000 MW, and it is provided by the flow of water through the pipes at a flow rate of 30000 kg / h. Water enters at 20 ° C, steam condenses at 50 ° C. Calculate the temperature of the cooling water leaving the condenser? Determine the required pipe length per pass? The properties of water at Tort = 300 K; Cp = 4180 j / kgK, μ = 855 × 10--6 Ns / m2, k = 0.613 W / mK, Pr = 5.83.