Fin-tube radiator

Finned tube radiators are a commonly used heat exchanger for gas, vapor, and liquid heat exchange. When dealing with gases and certain liquids, if the heat transfer coefficient of the film is very low, a larger heat transfer area is required to improve the heat transfer efficiency. Attaching fins to the basic heat transfer surface can meet this requirement. Finned tube radiators are a type of extended surface heat exchanger, belonging to the category of compact heat exchangers.

Fin-tube heat exchangers feature separate streams of fluids, with heat transfer occurring through an impermeable, sealed tube wall that separates the fluids, causing continuous heat exchange with the wall fins.
Fin-tube heat exchangers are a primary form of compact heat exchangers, where liquids or gases flow through the tubes, with air surrounding the tubes externally. Similar unit equipment is widely used in various fields such as textiles, dyeing, oil, chemicals, drying, and electricity. The internal medium of the tubes requires a high film coefficient for convective heat transfer, and air flows over the external fins in a crossflow manner. The film coefficient for heat transfer on the air side is lower than that of the internal medium, so fins are added externally to enhance heat transfer. The fins can be made of carbon steel, stainless steel, copper, or aluminum. Fin-tube heat exchangers are extensively applied in air-cooling and heating equipment.