Radiative heat transfer is the process in which heat is transferred through electromagnetic waves, such as infrared radiation. It occurs between objects that are at different temperatures and do not have direct contact with each other.
Radiative heat transfer differs from conduction and convection because it does not require a medium or direct contact between objects. It can occur through a vacuum and is primarily dependent on the temperature and surface properties of the objects involved.
The factors that affect radiative heat transfer include the temperature and emissivity of the objects involved, the distance between the objects, and the properties of the medium through which the radiation travels (such as air or a vacuum).
Radiative heat transfer is used in many real-world applications, such as in cooking with a microwave, heating with a space heater, and cooling with a refrigerator. It is also important in industries such as solar energy, where radiation from the sun is converted into heat for electricity generation.
The calculation of radiative heat transfer involves using the Stefan-Boltzmann law, which relates the radiation emitted by an object to its temperature and surface properties. Other factors, such as the geometry and orientation of the objects, also play a role in the calculation.