5 replies to this topic

[bosun]

I am developing heat exchanger monitoring spreadsheet. I already calculated current U value with current operating conditions and I have design U value of exchangers from the spec. sheet. So then, how can I calculate fouling to see if the heat exchanger is going to be plugged or not?

If anyone can answer my questions, I would really be appreciated.
Thank you in advance!

[srfish]

boson,

Calculate the film heat transfer coefficients for both sides. Then put all coefficients into the resistance form. Subtract the individual coefficients from the reciprocal of the current U to get the overall fouling factor.

[S.R.Shah]

If you shall have to monitor whether tube is in plugged condition or not;you have to consider seperately resistance of
dirt and heat conduction through it.Once tube is near plugged condition or say 50% pluged,outlet temperature of fluid shall rise or fall depending on whether it is hot fluid or cold fluid and pressure drop across tubes also rises.considering dirt thickness in plugged condition;outlet temperature of liquid can be calculated considering resistance through thickness of fouling.

[daure.tejaswini]

@ S.R Shah: You mentioned a nice point here. Sir, will you please let us know how these calculation are carried out?

[latexman]

I think you will get the idea from this reference:

http://en.wikipedia....ouling_deposits

Edited by latexman, 22 September 2012 - 06:35 AM.

[breizh]

Hi,

You may find some interest reading this paper.
Hope this helps

Breizh

Edited by breizh, 22 September 2012 - 07:10 AM.