Many alternative designs can be used in the design of shell and tube heat exchangers but need for optimizing design to reduce costs. There needs to be trial and error techniques to get most optimal design. Some parameters and constraints used in the design shell and tube heat exchanger are:
- Inlet temperature and outlet temperature.
- Fluid mass flow rate.
- Operating pressure.
- Pressure loss / drop that is allowed on both sides of heat exchanger.
- The properties of fluid.
- Fouling resistance for each flow.
In designing we also have to consider a decrease in pressure inside tube and inside hell. In addition, there are also some parameters of limitation, namely:
- The maximum velocity inside tube. When velocity of fluid flow inside tube is too high erosion will occur.
- The minimum velocity inside tube. The rate of fouling can increase if fluid velocity inside tube is too small.
- Tendency of vibrations on tubes. Many failures in heat exchanger is caused by the occurrence of flow-induced vibration on tubes. This event occurs because there is critical velocity in tubes that can cause vibrations on the tube.