Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

VARS based on Ammonia-Water Pair

1,114 views

Published on

Refrigeration Systems

Published in: Education
  • Be the first to comment

VARS based on Ammonia-Water Pair

  1. 1. Vapor Absorption Refrigeration Systems Based On Ammonia-Water Pair
  2. 2. • Vapour absorption refrigeration system based on ammonia- water is one of the oldest refrigeration systems. • Ammonia is used as a refrigerant and water is used as an absorbent. • Lithium bromide systems operate under very low pressures, the ammonia-water system is operated at pressures much higher than atmospheric . • Ammonia is both toxic and flammable. Hence, these systems need safety precautions.
  3. 3. Vapor Absorption Refrigeration Systems Based On Ammonia-Water Pair
  4. 4. For Ammonia-Water pair Circulation ratio - Is the ratio of the mass of the weak solution to the refrigerant mass flowrate. λ=mws/m
  5. 5. Condenser m1= m2= m Qc=m(h1-h2) Expansion Valve m2=m3=m h2=h3 Evaporator m3=m4=m QE=m(h4-h3)
  6. 6. Absorber m + mss = mws QA=mh4+λh10-(1+λ)mh5 Pump m5=m6=mws Wp=mws(h6-h5) Wp=λm(h6-h5) Heat Exchanger m6=m7=mws m8=m9=mss
  7. 7. Generator m7=m8+m1 QG=mh1+λmh8-(1+λ)mh7 Expansion Valve m9=m10=mws h9=h10 COP=QE/(QG+Wp)
  8. 8. Comparison Between Compression and Absorption Refrigeration Systems

×