Two of the most Common Type of Heat Exchanger

Arguably two of the most common type of heat exchanger are;

• Shell and Tube Heat Exchanger

• Air Cooled Heat Exchanger

We will go deep into Shell and Tube Heat Exchanger for a couple of Heat Exchanger but first, the basics.

1. Heat transfer occurs by three (3) basic mechanism, namely;

• Conduction - transmission of heat through direct contact

• Convection - transmission of heat through movement of liquid or gas

• Radiation - transmission of heat through thermal emission.

2. The main components of a shell and tube heat exchangers are;

• Shell - Outer most structure of the shell and tube refers as the shell side. It contains one of the two fluid streams (convection+radiation).

  • To contain liquid and pressure at shell side.

• Tubes - The inner tube, the other fluid is running inside the the tube. Heat transfer occures through the tube walls (convection+radiation)

  • To contain liquid and pressure at tubeside and as a heat transfer medium between cold and hot fluids.

• Tubesheets - Plate at both ends of the shell that supports and seal the tubes.

  • To hold both end of the tubes and as a barrier between two fluids at tubeside and shellside.

• Baffles - Internal plate that guides the fluid flow promoting turbulence thus enhancing heat transfer.

• Tube Bundles - The assembly of tubes, baffles, tie-rods, tubesheets within the shell.

• Headers - Inlet and outlet chambers for both shell side and tube side fluids which connect the tubes through external piping.

• Impingement Plate - at shell entrance and exit (if required) are to protect the tubes from erosion due to velocity of flow.

We will be discussing on the design requirements and mechanical calculations and we will end our topic with a detail calculation of the shell thickness in accordance with international code and standards i.e ASME VIII Div 1 UG-27.

Its not that complicated.

I will guide you along the way.