Water enters a heat exchanger at 85°C with a flow rate of 2.5 kg/s. Dry atmospheric air enters the..

Water enters a heat
exchanger at 85°C with a flow rate of 2.5 kg/s. Dry atmospheric air enters the
heat exchanger at 20°C at a flow rate of 12 kg/s. It is desired to select a
cross flow heat exchanger for this task such that the air leaves the heat
exchanger at a temperature near, but not less than, 60°C. The design engineer
is considering three possible cross flow heat exchangers that have been
identified as viable solutions to accomplish this task;

a. Calculate the outlet
temperature of the air for the three heat exchangers. Is the minimum outlet
temperature of 60°C satisfied?

b.

Water enters a heat
exchanger at 85°C with a flow rate of 2.5 kg/s. Dry atmospheric air enters the
heat exchanger at 20°C at a flow rate of 12 kg/s. It is desired to select a
cross flow heat exchanger for this task such that the air leaves the heat
exchanger at a temperature near, but not less than, 60°C. The design engineer
is considering three possible cross flow heat exchangers that have been
identified as viable solutions to accomplish this task;

a. Calculate the outlet
temperature of the air for the three heat exchangers. Is the minimum outlet
temperature of 60°C satisfied?

b. Calculate the
effectiveness of each of the heat exchangers. Is there an advantage to one
configuration over the others?

c. Which heat exchanger
would you recommend, and why?