What are the three ways of heat transfer?

The three ways of heat transfer

1, radiation, the use of infrared radiation between the objects and absorption of each other, without the need for any material to achieve temperature balance.

2, conduction, direct contact between objects, heat energy directly to the atomic vibration, from the high temperature to the low temperature.

3, convection, the fluid between the object as a medium, the use of fluid thermal expansion and contraction and can flow characteristics, the transfer of thermal energy.

Thermal radiation

All objects with temperatures above absolute zero can produce thermal radiation, the higher the temperature, the greater the total energy radiated. The spectrum of thermal radiation is a continuous spectrum, wavelength coverage theoretically from 0 until ∞, the general thermal radiation mainly by the longer wavelength of visible light and infrared propagation.

The lower the temperature, mainly invisible infrared radiation, when the temperature of 300 ℃ when the strongest wavelengths of thermal radiation in the infrared region. When the temperature of the object is above 500 ℃ to 800 ℃, the strongest wavelength component of thermal radiation in the visible region.

Radiation source surface in a unit of time, unit area of the energy emitted (or absorbed) with the nature of the surface and the temperature of the surface is related to the surface, the darker and rougher the surface, the ability to emit (absorbed) energy is stronger. Any object radiates energy in the form of electromagnetic waves to its surroundings. When the radiated electromagnetic wave encounters an object on its propagation path, it will stimulate the thermal movement of the microscopic particles that make up the object, causing the object to heat up.