Cooling Machine (refrigerator)

Page 1

HOW DOES a refrigerator WORK?



1. The constricts the refrigerant vapor, raising its pressure, and pushes it into the coils on the outside of the refrigerator. 2. When the in the coils meets the cooler air temperature of the kitchen, it becomes a liquid. 3. Now in liquid form at , the refrigerant cools down as it flows into the coils inside the freezer and the fridge. 4. The refrigerant cooling down the air.

inside the fridge,

5. Last, the evaporates to a gas, then flows back to the compressor, where the cycle starts all over.


Compressor from the evaporator is compressed, raising it temperature and boiling point adiabatic compression

Cold vapor

T, b.p. ~ P work done on the gas


Condenser from the compressor condenses outside the cold box, releasing latent heat isothermal, isobaric condensation (horizontal line on PV diagram)

Hot vapor

high temperature T (hot) latent heat of vaporization Q (hot)


Expansion Valve (throttling valve) Hot liquid from the condenser is depressurized, lowering its temperature and boiling point adiabatic, isochoric expansion (vertical line on PV diagram).

T, b.p. ~ P no work done W = 0


Evaporator Cold liquid from the expansion valve boils inside the cold box, absorbing latent heat isothermal, isobaric boiling (horizontal line on PV diagram)

low temperature T (cold), latent heat of vaporization Q (cold)


Reference THE PHYSICS HYPERTEXTBOOK. (2015). REFRIGERATORS. Retrieved on December 6th, 2015, from http://physics.info/refrigerators/ Sforza, Nicole. (2015). How Does a Refrigerator Work? RETRIEVED ON DECEMBER 6TH, 2015, FROM http://www.realsimple.com/food-recipes/toolsproducts/appliances/how-does-refrigerator-work


Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.