Thermodynamics of Actual Combustion

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Thermodynamics of Actual Combustion

• P M V Subbarao
• Professor
• Mechanical Engineering Department

Selection of Conditions for Efficient and
Eco-friendly Combustion.
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Mathematical Model for Completion of Reaction
For every fuel, a designer should know all
possible reactants !!! Some products will
influence the efficiency of reaction. Few other
may not influence the efficiency of reaction but
severely affect the environment. The optimal
parameters for efficient reaction may not be
optimal for safe reaction !!
3
Generalized Theory of Extent of Reaction Possible
P1,T1
P3,T3
P2,T2
Entropy of Universe
Extent of Reaction
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Model Testing for Determination of important
species
Water Flow Rate
Air Flow Rate
Flue gas Analysis
Fuel Flow Rate
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Results of Model Testing.

• For a given fuel and required steam conditions.
• Optimum air flow rate.
• Optimum fuel flow rate.
• Optimum steam flow rate.
• Optimum combustion configuration!!!

• Realization of MATtr Theory
• Mixing Fuel preparation systems.
• Air Draught systems.
• T Preheating of fuel.
• t Dimensions of combustion chamber.
• r Turbulence generation systems.

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Air composition

• Air is a mixture of nitrogen, oxygen CO2 and some
  inert gases.
• It also consists of water vapours of varying
  quantity.
• The mean percentage of main atmospheric
  constituents in clean air and their mean
  residence times are presented below.

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Humid Air
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Combustion with Ambient Air
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Actual Combustion with Moist Air Fuel