The main component of a heat exchanger is a bundle of pipes arranged in parallel. Within these pipes, one fluid flows internally, while another flows externally. Heat is transferred through the pipe walls, gradually reducing the temperature difference between the two fluids.

To further enhance heat transfer efficiency, tubular heat exchangers are often equipped with a structure known as fins. The presence of fins increases the surface area of the tube walls, thereby enhancing heat transfer. This design allows tubular heat exchangers to achieve a significant amount of heat transfer within a relatively small footprint.