Heat transfer from pipe/equipment steel wall to gas inside pipe/equipment

[Nansen]

Hi all!

I wish to calculate the heat transfer from a pipe/equipment wall heated by fire, into the gas inside the pipe/equipment. The heat input to -and temperature rise of the wall is calculated with standard radiation and convection equations. Compared to liquid filled sections the heat input to the gas will be small due to much lower heat transfer coefficient and thermal mass of the gas. My initial thought was to use a heat transfer coefficient between the gas and steel wall. However I am unsure how this is calculated or where it can be found and whether other factors should be included in the calculations.

I am preparing a spreadsheet in Hysys simulation tool for the calculations so I have the resources of Hysys available for the calculations if that can be of help.

Any advice on this subject or suggestions for good relevant resources would be greatly appreciated.

Thanks!

 

[MortenA]

So if you have HYSYS - any specific reason why you wont use the "fire heater" unit op?

 

[Nansen]

Hi Morten, thank you for your reply!

The spreadsheet is within the depressuring utility in Hysys. It is dynamic and the calculations are to be used for a shut down process section that is depressuring while a fire is engulfing the section. In the utility there are several inputs and factors that can not be transferred to the fired heater.

What I am looking for is suggestions for equations that I can implement into the spreadsheet.