









































































NOTE:

Yellow/Red

cells indicate user
input data. You must input your own data in these cells to obtain results for your air heater.












































Air Heater Leakage Determination












AH O_{2} In




AH O_{2} Out








%



%





Air Heater Leakage

=









X


=


% Air Heater Leakage





















AH O_{2} Out




O_{2} In Air







%



%




















































































Air Heater Gas Exit Temperature Correction





NOTES:





Properly stated,
"Corrected Gas Exit Temp" is asmeasured temperature, and includes
the temperaturereducing effect of air heater leakage. "Uncorrected Gas Exit Temp" is
the same temperature, but corrected to a "No Leakage"
condition. This seemingly backwards
nomenclature came about in the early days of boiler design, when the
designers would calculate air heater heat transfer and then had to "correct"
the resulting temperature calculation to account for leakage.








The following
calculation directly references the air heater leakage from the calculation
just above. If you already know air
heater leakage percent and do NOT know inlet and outlet O_{2}, then just input "fake" O_{2} values that result in the known leakage.





AH Leakage


Cp_{A}  Specific Heat of Air





AH Gas Exit
Temp,
No Leakage



%



Default = .246









=


°F




=







X






X


Gas Out Temp




Air In Temp


+


Gas Out Temp
























°F













%


Cp_{G}  Specific Heat of Gas











Default = .252












































Air Heater XRatio





NOTES:





XRatio (XR) is the
ratio of the heat capacity of the air passing through the air heater to the heat capacity of the gas passing through the air
heater. The gas out temperature used
in this calculation must be at "No Leakage". The calculation below directly references
the gas exit temperature corrected to no leakage, calculated above.









Gas In Temp


Gas Out Temp








°F



°F





AH XRatio

=












=



(No
Units)


















Air Out Temp


Air In Temp







°F



°F












































Air Heater Gas Side Efficiency





NOTES:





Gas side efficiency
is the ratio of gas temperature drop (at no leakage), to the Temperature
Head. Temperature Head is the gas
inlet temperature minus the air inlet temperature. The calculation below directly references
the gas exit temperature corrected to no leakage, calculated above.









Gas In Temp


Gas Out Temp








°F



°F





AH Gas Side Efficiency

=












X

100%


=



















Gas In Temp


Air In Temp







°F



°F






































