An engineer has concluded during a heat exchanger design procedure that three important constraints limit his decision-making process. The first is that the pressure drop of one of the two fluids is...

An engineer has concluded during a heat exchanger design procedure that three important constraints limit his decision-making process. The first is that the pressure drop of one of the two fluids is larger than the value permitted. The second is that the cost of one of the two fluids used in the exchanger limits the mass flow rate of that fluid through the exchanger. Finally, the third is that the temperature difference between the two fluids at the exit of the exchanger must be reduced due to the need to increase the plant’s overall efficiency. From a study of the design methodology chart presented, uncover in which of the suggested segments of the design procedure these constraints are probably identified.