In: Mechanical Engineering
A heat exchanger with 1 body - 4 pipe passages and 109 pipes (2.6 cm diameter each, 4 m long thin wall per passage) at each passage will be used to heat the air. The water enters the pipes with a mass flow of 8 kg / h at 350 K temperature and the air enters the body with a mass flow of 18 kg / h at a temperature of 15 C. The pollution factor of the sediment formed inside the pipe over time is 0.0026 m2K / W. The transport coefficients on the inner and outer surfaces of the pipes are estimated at 450 and 200 W / m2K, respectively. Using specific temperatures at 25 C for air and water
a-) The effectiveness of the heat exchanger by drawing the shape of the problem,
b-) Heat transfer rate (kW),
c-) Calculate the outlet temperatures (C) of the water and air and show the temperatures in the T_L diagram.