Hydrogen is a possible future fuel for spark-ignited engines promising much cleaner combustion (less emissions). It...

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Hydrogen is a possible future fuel for spark-ignited engines promising much cleaner combustion (less emissions). It comes with a higher heat density (QHV= 120 MJ/kg) compared to the gasoline (QHV = 44 MJ/kg) on mass basis. However, a disadvantage is that due to lesser molecular weight it displaces more air in the intake manifold, hence leading to lesser air intake which is proportional to the partial pressure of the air. For H₂ and gasoline fuel (C8H18), compare the following for the same SI engine running at same rpm and operating at unity equivalence ratio (p = 1): a. Stochiometric air to fuel ratio b. Partial pressure of air in the intake manifold Heat content in the fuel-air mixture entering the engine per cycle For comparison, engine parameters such as displaced volume, rpm etc. can be kept in symbolic form. Assume total mixture pressure and temperature in intake manifold after fuel injection and complete vaporization of gasoline are same as that with H₂. Hydrogen is a possible future fuel for spark-ignited engines promising much cleaner combustion (less emissions). It comes with a higher heat density (QHV= 120 MJ/kg) compared to the gasoline (QHV = 44 MJ/kg) on mass basis. However, a disadvantage is that due to lesser molecular weight it displaces more air in the intake manifold, hence leading to lesser air intake which is proportional to the partial pressure of the air. For H₂ and gasoline fuel (C8H18), compare the following for the same SI engine running at same rpm and operating at unity equivalence ratio (p = 1): a. Stochiometric air to fuel ratio b. Partial pressure of air in the intake manifold Heat content in the fuel-air mixture entering the engine per cycle For comparison, engine parameters such as displaced volume, rpm etc. can be kept in symbolic form. Assume total mixture pressure and temperature in intake manifold after fuel injection and complete vaporization of gasoline are same as that with H₂.

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A Stochiometric air to fuel ratio Gasoline The stochiometric air to fuel ratio AFR for ... View the full answer