Calculating temperature change

[Micko]

Hello to all,

I'm reading one article about boiler. I have found one interesting fact about air preheater used in industrial boiler. It goes something like this "Approximately 1% of fuel is saved for each 40 F rise in combustion air temperature.

Now, since I'm in Europe, I want to know how much this is in deg Celsius.
Just want confirmation about this:
since Tc = 5*(Tf-32)/9, this will be Tc2 = 5*(Tf1+40-32)/9.
This will lead to: Tc2-Tc1 = 40/9 +160/9 = 200/9 = 22.2 C
Is this correct?

 

[russ_watters]

Yes, though since you are just doing delta-T's, you don't need to attach them to their respective scales to do the math. Just multiply or divide by the ratio: 40/1.8=22.2

 

[Micko]

OK, thanks