HEAT TRANSFER
Heat transfer is the part of thermodynamics, it is the movement of heat from one thing to another by means of radiation, convection and conduction. All forms of heat transfer may occur in some systems at the same time.
HEAT
Heat is the amount of thermal energy that is transferred between two objects due to temperature difference.
MODES OF HEAT TRANSFER
1.Conduction
2.Convection
3.Radiation
1.Conduction
*Conduction is the transfer of heat from one part of a substance to another part of the same substance (or) from one substance to another in physical contact with it, without appreciable displacement of molecules forming a substance.
*In solids, the heat is conducted by the following two mechanisms
1)By lattice vibration
2)By transport of free electrons
2.Convection
*Convection is the transfer of heat within a fluid by mixing of one portion of the fluid with another.
1)Free (or) Natural Convection
2)Forced Convection
3.Radiation
*Radiation is the transfer of heat through space (or) matter by means other than conduction (or) convection.
*Radiation is a process in which energetic particles (or) energetic waves travel through a medium (or) space. There are two types of radiation, ionizing and non-ionizing.