You may double click on the image to see an expanded view, after viewing the image, click on the Back key in your browser application to return to this page. On the left hand side, we see a schematic of the heat exchanger, depicting the flow of the two liquid streams inside the tubular heat exchanger. Note that the heat exchanger has two tubes, one inside the other. One of the tube carries the hot fluid and the other carries the cold fluid. As the liquid streams flow inside the heat exchanger, heat is transferred from the hot to the cold fluid stream.
Heat is transferred from the hot fluid to the cold fluid stream in a radial direction.
Heat transfer from the hot fluid to the surface of the outside wall of the inner tube is by convection, through the wall by conduction, and again from the inside wall of the inner tube to the cold fluid by convection.