Why Hydrogen Cooling

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Why Hydrogen Cooling 
  • Lowest density gas yields lowest drag
  • Highest heat conductivity of any gas
  • Controlled atmosphere to maintain Clean & Dry
  • Inexpensive 
  • Easy to detect 
  • Excellent electrical properties
  • Easy to manage – not readily miscible with CO2 purge gas
  • Flammable


Hydrogen Flammability Range


  • Hydrogen has a wide flammability range generally 4% to 75% hydrogen in air is hydrogen flammability range.
  •  So 4% is lower flammability range & 75% is upper flammability range. If hydrogen in air is bellow 4% then no chance of flame & if hydrogen percentage is above 75% then no chance flammable.then always in generator maintain hydrogen purity as higher as possible.above upper flammability level no chance of ignition if system is leak proof. Generator is always under pressure (higher than atmosphere).
  • Generally in generator casing hydrogen purity is maintain above 96%.


  • H2 is lightest  gas  with   0.09 gm/litre while air is 1.3  i.e. 14.4 times.
  • Thermal capacity of H2 as gas is high.
  • Thermal conductivity of H2 is 5 times that of  air.
  • Is specific heat is  3.42 at 0°C, as compared to 0.237 of  air.
  • 2 H2 + O2 mixture ignites on adiabatic compression at 526°C, and 3H2 + O2 at 544°C.












































































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