Heat Transfer System

Introduction :

Heat Transfer Definition :

Heat transfer is a process where heat is getting transferred from one place to another or heat exchange between two objects or its surroundings.

When ever a body is heated, heated the heat transfer takes place from that heated body to its surroundings or from heated part of the body to the cold part of the same body or heat transfer from hot body to water or air till the both body and the surrounding reach equilibrium.
Such spontanious heat transfer takes place on the second law of thermodynamics, that is always the heat transfer takes place from a reagion of higher temperature to the region of lower temperature.

                                                                                                                                                                                                    

Modes of Heat Transfer or Heat Tranfer Mechanism:

basically the transfer in three modes, that is

1. Conduction:

the conduction is a process where the heat is transfered between two solid materials in thermal contact, when ever one part of the body is heated the heat is transfered to the other reagion of the same part or the body which is in thermal contact with it through the atoms, in other words the heat transfer between the vibrating adjacent atoms is called Conduction.
steady state conduction is a process where the rate of heat entering into a body is equal to the rate of heat coming out of the body.

Convection and Radiation

Convection:

convection is a process of heat transfer where the heat is transferred through a fluid and gases. convection is mainly due to the heat transfer with the help of liquid and gases. here the heat transfer is mainly due to the flow of molecules in the fluid.
convection occurs due to newtons law of cooling, that is the rate of heat loss by a body is directly proportional to the difference in temperature between the body and the surrounding.

Radiation:

the process of heat transfer through the empty space by the help of electromagnetic waves is called radiation heat transfer. radiation does not require any medium for its process to happen, as it occurs with the help of electromagnetic waves radiation will occurrs in perfect vacuum.

by using the reflecting mirrors, the thermal radiation can be concentrated at a tiny part. the solar energy works with the help of this process.