[Weiqiang Liu]

Hi all,

I am doing a combustion simulation with fluent. when determining convergence, I checked the flux report and tried to checked energy balance of the whole system.

There are two options to check. first is total heat transfer rate and the second is total sensible heat transfer rate.

I am wondering what is the difference of heat transfer rate and sensible heat transfer rate?

Best regards

Weiqiang

[vinerm]

For reacting flows, sensible heat transfer rate is not conserved. Therefore, you should look at total heat transfer rate. These details are given in User Guide.

[Weiqiang Liu]

Originally Posted by vinerm

For reacting flows, sensible heat transfer rate is not conserved. Therefore, you should look at total heat transfer rate. These details are given in User Guide.

Hi, Vinerm,

Thanks very much. Your reply is really helpful!

Best regards

Weiqiang

[Weiqiang Liu]

Originally Posted by vinerm

For reacting flows, sensible heat transfer rate is not conserved. Therefore, you should look at total heat transfer rate. These details are given in User Guide.

Hi Vinerm,

I just checked the user guide of ansys. sensible heat transfer rate excludes reaction enthalpy and reaction enthalpy is illustrated separately. Therefore sensible heat transfer rate adding with reaction enthalpy is conserved, right?

Weiqiang

[vinerm]

Yes, that's correct. But if the species and/or energy equations are well converged, then both will show a small number and could be used as convergence criteria.

[Weiqiang Liu]

Originally Posted by vinerm

Yes, that's correct. But if the species and/or energy equations are well converged, then both will show a small number and could be used as convergence criteria.

Hi Vinerm,

Thanks very much! my problem is: monitored value, species profile or contour are steady. however, total heat transfer rate or sensible heat transfer rate are oscillating. Sometimes they are tens of W and sometimes they are close to 0.

I am wondering how can I avoid this phenomenon. Because I am really not very sure whether the case is converged when energy balance is oscillating.

ps: I have both gas phase and surface phase mechanism in my case.

Best regards

Weiqiang