In: Mechanical Engineering
How to make evaporator, types of evaporator, materials and formulas to find out its properties, please elaborate everything about evaporator.
An evaporator is a part of refrigeration cycle which absorbs the heat of a body untill the refrigerant leaves as a superheated gas due to properties of refrigerant lesser temperature of body is obtained. The basic principle of working of every evporater is to absorbs heat while boiling off the liquid refrigerant and finally to produce cooling effect. Heat always travels rom a warmer body to a cooler one. Hence the evaporator must be at a lower temperature than its surroundings.Evaporators are usually made of copper ,aluminum because of their high heat conducting properties and low cost.
Types of Evaporators:-
The three design applications for evaporators—
1) Bare tube Evaporator
2) Plate type Evaporator
3) Finned tube Evaporator
On the basis of temperature range evaporators are categorized as:-
1) Low temperature :- They can work on 32°F and below temperature range.
2) Medium temperature:- They can work on 32°F to 40°F temperature range.
3) High temperature :- These kind of evaporator suitable for higher 40°F to 50°F temperature range.
On the basis of heat transfer two types of evap.:
1) Forced Convection Type:- These kind of evaporator uses external agency like fan or pump to force the liquid being cooled over the evap.
2) Natural Convection Type :- In these kind of evaporator refrigerant flows naturally to the evaporator due to the density differences of warm and cold fluid.
Evaporator Design Factors or formula:-
There are 3 main factors to consider in designing an evap.
1) Liquid and Refrigerant Vapor :- It should have enough space for the sepration of liquid and vapour from the heated liquid.
2) Pressure Drop :- It should be too much between the outlet and the inlet.Evaporator must be posses sufficient space for the refrigerant circulation.
3) Temperature :- It should have have enough surface to absorb the required heat load so that temperature should not be exccesive.