[whysoserious]

I want to ask what the error means and how can I fix it?

P.S.: I am using ECFM-3Z to simulate non-premixed combustion of natural gas dual fuel engines. The error occurs when the piston approaches the TDC. And, this is also the time when the spray begins. However, when I shift ECFM-3Z to SAGE, the error doesn't appear again, and my case runs smoothly

[dprobst]

ECFM-3Z does not have dual fuel capability.
SAGE can be used for those applications.

[whysoserious]

Originally Posted by dprobst

ECFM-3Z does not have dual fuel capability.
SAGE can be used for those applications.

Dear Dprobst,
Hi. Thank you for your quickly reply. I already know that SAGE has dual fuel capability. And, I have run several cases using SAGE by now. But, the engine scale, which I am dealing with, is so large that it is a time-consuming choice to use SAGE. That's why I explore the dual fuel capability of other combustion models. If ECFM-3Z is not an appropriate choice, do the FGM, G-equation and RIF have this capability?
By the way, I change my case setup from dual fuel to single fuel, but another error arise when the piston approaches TDC and the injection hasn't finished. The screenshot of run.log is attached.
Thank you!

[dprobst]

Hi whysoserious:

I asked our combustion group team leader to comment on the applicability of simplified combustion models on a dual fuel case:

The fundamental issue here is not how many fuels the combustion models are able to handle. The questions is that which model can handle diffusion, premixed combustion plus the transition between diffusion and premixed scenario. FGM, G_EQN and RIF are designed to mimic either diffusion or premixed combustion. That's why these models are no better than SAGE.

[zhangyan]

Originally Posted by dprobst

The fundamental issue here is not how many fuels the combustion models are able to handle.
The questions is that which model can handle diffusion, premixed combustion plus the transition between diffusion and premixed scenario.
FGM, G_EQN and RIF are designed to mimic either diffusion or premixed combustion.

Dear Dan,
As far as I know, we can use combustion-regime indicator to distinguish premixed and diffusion.
Such as FGM, for premixed regime, we can use homogenous reactor to generate FGM table. For diffusion regime, we can use counter flow diffusion reactor to genrerate FGM table.
In this way, FGM can deal with partial premixed combustion.

But my question is, how FGM deal with dual fuel?
Does FGM have the potential to deal with dual fuel ?
or it can't do this essentially?