TYPES OF HEAT TRANSFER

 

HEAT TRANSFER 

Heat transfer is the exchange of heat energy between the materials ( solid / liquid / gas ) because of difference in temperature. Heat energy always has a tendency to flow from high temperature area to low temperature area. There are three different types of heat transfer conduction, convection and radiation.

CONDUCTION 

Conduction is heat transfer between the object by the direct physical contact. Here heat is transferred from hotter place to cooler place by vibration of particles(when heated kinetic energy of particles increases) of that object. Conduction occurs through heated solid object, heat transfer from hotter part of solid to cooler parts if the are in direct contact to each other.

Eg:- heat transfer in metals 

CONVECTION 

In convection heat transfer is take place due to the temperature difference in fluids. In fluids density of particles differs as result of increase in temperature. So in fluids particles moves from hotter area to colder area due to density difference.

Eg:- heat transfer in water and air

RADIATION 

Radiation is heat transfer occurs as electromagnetic waves. A hot body emit heat as electromagnetic waves . Radiation can transfer through vacuum or through any medium (solid, liquid and gas)

Eg:- sunlight transfer heat through radiation