Condensing Heat Transfer Coefficient 1

[aerospace35]

Hi,

I am designing a small condenser to remove aviation fuel vapours (internal to the tube) from a small gas flow. Could someone please tell me if the attached calculation approach is correct for a vertical tube condenser under laminar flow conditions where the condensation process is inside the tube?

Very Best Regards,

Aerospace35

 

[Latexman]

I didn't check the math, but the method is sound. This is about 100 Btu/lb/ft²/^oF. Kind of low, but this is Nusselt theory and N_Re is low. You might want to check using the Dukler Plot, if nothing else it'll be a good cross check.

Good luck,
Latexman

 

[Latexman]

Sorry. Change lb to hr.

Good luck,
Latexman

 

[aerospace35]

Many Thanks Latexman - do you know where I might find the Dukler plots to make this comparison.

Regards,

Aerospace35

 

[Latexman]

It's documented in Perry's Chemical Engineers' Handbook. It may be in other heat transfer textbooks, but thats where I look it up.

Good luck,
Latexman

 

[Chance17]

Do you need to include ID or OD fouling fctors ?

 

[Latexman]

Good point. The OP has calculated h_i, but U is needed to design a complete unit.

Good luck,
Latexman

 

[aerospace35]

Hi,

Checked my value via the Dukler plot and it gave an answer in the 115 to 120 Btu/hr/ft2/oF - so it's in the ballpark. Conversion to SI units as per my calc is * 5.687. What a helpful diagram - so much must have gone into working that little lot out!
I wasn't so sure on the Dukler plot what deltaT represented on the right handside L*deltaT column.I reasoned it was the temperature between the wall of the condenser and the vapour going through it - Any views anyone?

Thanks to all for your views and answers on this - been v.helpful.