A heat sink is a heat exchanger used to transfer thermal energy from one medium to another for cooling and heating. Most radiators are constructed to function in automobiles, buildings, and electronics. The heat sink is always a source of heat for its environment, although this can be used to heat the environment or to cool the fluid or coolant supplied to it for engine cooling. Despite this, most heat sinks transfer most of the heat by convection rather than heat radiation.
The Roman massacre was an early example of a radiator used in building space heating. Franz San Galli, a Russian businessman born in Prussia, who lived in St. Petersburg, invented the heating radiator around 1855 and patented the radiator in 1857, but Joseph Nassen developed it in 1841. An original radiator and won the title of many Americans. Hot water and steam heating patents.
Radiation and convection
Heat transfer from the heat sink occurs through all common mechanisms: heat radiation, convection of incoming air or liquid, and conduction into air or liquid. The heat sink can even transfer heat through a phase change, for example, drying a pair of socks. In practice, the term "heat sink" refers to any of a number of devices in which liquid is circulated through an exposed conduit (typically having fins or other means of increasing surface area). The term "convection" refers to a type of device in which the heat source is not directly exposed.
To increase the surface area available for heat exchange with the surroundings, a radiator will have multiple fins, in contact with the tube carrying liquid pumped through the radiator. Air (or other exterior fluid) in contact with the fins carries off heat. If air flow is obstructed by dirt or damage to the fins, that portion of the radiator is ineffective at heat transfer.
Radiators are often used to heat buildings. In a central heating system, hot water or sometimes steam is generated in a central boiler and circulated through a radiator in a building through a pump, where the heat is transferred to the surrounding environment.