Heat Exchanger

Heat Exchanger

Heat Exchanger

it is at the thermodynamic device in which transfer of heat takes place from one thermodynamic substance to others thermodynamics substance due to presence of temperature difference in an adiabatic system

          The design of heat exchanger is based on the point that heat required minimum resistance to follow the heat with minimum effort and cost 

one substance is called hot substance and another substance is called Cold fluid 

classification of the heat exchanger 

on the basis of mixing of load on the basis of the direction of flow 
on the basis of construction 
on the basis of phase changes 

Direct mixing heat exchanger

In this type of heat exchanger, hot fluid and cold fluid directly mixed in an insulated chamber and transfer of heat take place between them such type of heat exchanger are used in case of pure substance only.

Indirect mixing type HE

In this heat exchanger fluid and hot fluids are not directly come in contact with each other two ways of his transfer.

regenerator type HE

In regeneration hot fluid is passed through a chamber in which it shares the heat energy with a pipe wall and then cold fluid it passes through the same space and heat is transferred from space to the cold fluid in such type of heat exchanger the resistance is minimum and heat flow is maximum.

Recuperator type HE

In this heat exchanger, The Hot and Cold flu passes at the same instance and which transfer takes place between them 

on the basis of the direction of flow 

parallel-flow heat exchanger

In this heat exchanger Hot and Cold fluid flow in the same direction 

Counterflow heat exchanger 

In this heat exchanger Hot and Cold fluid move in opposite direction to each other crossflow in this heat exchanger. Hot and Cold flow perpendicular to each other.

Concentric tube type heat exchanger

In this, HE a number of concentric tubes are used in such a way that hot and cold fluid passes the tube simultaneously.

Shell and tube type heat exchanger 

In this heat exchanger tube is passed through the tube while another fluid flows through the shell it can be a single cell or multicell.

Condenser type HE

In this case, the condenser temperature of hot fluid remains constant while the temperature of the cold fluid increases the hot fluid behave as a thermal energy reservoir of infinite energy resources.

Evaporator type HE

In this case, we have as a wire of lower temperature remains constant temperature in this reservoir the temperature of hot glue defeated in this case

(LMTD)Log mean temperature difference

it is defined as a constant temperature difference that is applied to the heat exchanger. it would transfer the same amount of heat under the balanced condition of the temperature difference hm sons there are a certain number of persons 

Assumptions-

1. steady-state heat transfer takes place inside the heat exchanger
2. the heat exchanger is perfectly insulated only conduction and convection mode of heat transfer are considered
3. the system is a homogeneous and isotropic heat exchanger