In the first part of this article, heat exchanger design basics were introduced. In the following article, the design formulations and calculations are introduced.
As mentioned in part 1, overall heat transfer in heat exchanger in increased in the flow are set to be countercurrent. As a result, only countercurrent double pipe heat exchanger design is discussed here. To start the design of a double pipe heat exchanger, the first step is to calculate the heat duty of the heat exchanger. It must be noted that for easier design, it’s better to ignore heat loss in heat exchanger for primary design. The heat duty can be defined as the heat gained by cold fluid which is equal to the heat loss of the hot fluid. It can be calculated as: