Heat exchanger permits the transfer of heat from a fluid to another fluid (gas or liquid) without direct contact or mixing. There are many forms of heat exchangers. In all types of heat exchangers, the fluids are operating in different temperature and physically separated 3. Plate heat exchanger, adiabatic wheel heat exchanger, shell and tube heat exchanger and regenerative heat exchanger are some of the types of heat exchangers. Heat exchangers efficiency depends on the economic basis along with the type of service they are needed for. Furthermore, liquids flow direction can distinguish one heat exchanger to another. Liquids flow direction can be cross-flow, parallel-flow or countercurrent. 3
In this project we were requested to check whether an exiting heat exchanger would be appropriate to achieve specific duty. Additionally, to estimate the tube and shell side pressure drop. Shell-and-tube heat exchanger is suitable for higher-pressure purposes, which makes it the most commonly used form of heat exchanger. It consists of more than shell and many tubes inside it. Tubes can be two groups:
1. The liquid to be cooled or heated.
2. The first fluid’s duty is cooling or heating the second fluid. 3
Furthermore, shell-and-tube heat exchanger forms differ depending on the number of shell-and-tube passes, shown figure 1. One shell pass and two-tube pass shown in part (a) of figure 1 however two shells and two-tube pass shown in part (b). Through a counter flow, as the shell and tube inlets flow once between point m and n they finish one pass. Tubes inside the shell contain several baffles. Baffles help to increase the convection coefficient (h) of fluid in the shell. They are also beneficial for decreasing the vibration of flow-induced tube. 4