R & AC
-
Upload
nishit-kumar -
Category
Documents
-
view
217 -
download
0
description
Transcript of R & AC
![Page 1: R & AC](https://reader036.fdocuments.in/reader036/viewer/2022082506/5695cf8d1a28ab9b028e90b0/html5/thumbnails/1.jpg)
REFRIGERATION & AIR CONDITIONINGTwo related areas in Mechanical Engineering.
Refrigeration : Preservation of certain materials by cooling them to predetermined low temperature.
Air conditioning : Maintaining the temperature, humidity and purity of certain closed space to provide human comfort or to facilitate certain industrial processes.
Involves, Heating / Cooling and Humidifying / Dehumidifying.Comfort conditions : 20 to 25°C and 50 to 55 Relative Humidity.
Cryogenics: Study of very low temperatures and how materials behave at these temperatures. Normally below – 150°C.
![Page 2: R & AC](https://reader036.fdocuments.in/reader036/viewer/2022082506/5695cf8d1a28ab9b028e90b0/html5/thumbnails/2.jpg)
SPECIFIC & RELATIVE HUMIDITIESSpecific humidity, = =
As more water vapor/moisture is added, ‘’ increases till the air is saturated.
Any further addition of moisture leads to condensation.
Relative humidity, RH = where, mg – max. water vapor air can hold.
![Page 3: R & AC](https://reader036.fdocuments.in/reader036/viewer/2022082506/5695cf8d1a28ab9b028e90b0/html5/thumbnails/3.jpg)
REFRIGERANTSWorking fluid in the Refrigerators / Air conditioners
R12 – CCl2F2
R22 – CHClF2
R134 – C2H2F4
Properties:Low Boiling pointHigh value of hfg
Non-flammableNon-toxicNon-corrosiveLow cost, etc.
![Page 4: R & AC](https://reader036.fdocuments.in/reader036/viewer/2022082506/5695cf8d1a28ab9b028e90b0/html5/thumbnails/4.jpg)
VAPOR COMPRESSION REFRIGERATION SYSTEM
Schematic and p-h diagrams
![Page 5: R & AC](https://reader036.fdocuments.in/reader036/viewer/2022082506/5695cf8d1a28ab9b028e90b0/html5/thumbnails/5.jpg)
DOMESTIC REFRIGERATOR
![Page 6: R & AC](https://reader036.fdocuments.in/reader036/viewer/2022082506/5695cf8d1a28ab9b028e90b0/html5/thumbnails/6.jpg)
TONNE OF REFRIGERATION (TR)
It is the measure of cooling capacity.
A cooling that can produce 1 ton (approx. 900 kg) of ice at 0°C from water at 0°C in 24 hours.
1 TR = 12,600 kJ/hr (211 kJ/min.)
![Page 7: R & AC](https://reader036.fdocuments.in/reader036/viewer/2022082506/5695cf8d1a28ab9b028e90b0/html5/thumbnails/7.jpg)
WINDOW AIR CONDITIONER
![Page 8: R & AC](https://reader036.fdocuments.in/reader036/viewer/2022082506/5695cf8d1a28ab9b028e90b0/html5/thumbnails/8.jpg)
WINDOW AIR CONDITIONER