Problem in Border grids

[anhvulee]

Dear Envi-MET team,

I'm running a model (as described in the attached picture) with 5 nesting grids and got a warning about "Flow module failed to convert solution"
I've read some thread in previous topics and saw the feedback about finding the failed position on grids.

Please tell me how to fix this issue and how to find the failed position on grids.

Thank you so much

[Tim]

Hi,

I see in the screenshot that UV are around 0 m/s. The wind field can thus not be calculated accurately and the model gets instable. Increase the wind speed if is rather low. Otherwise, replace the dense LAD trees with trees of low LAD density.

Best regards,
Tim

[anhvulee]

Hi Tim,

Thanks for your reply. Btw, How could I define the place that take a failed calculated?

[Tim]

Hi,

It is not displayed in these error messages.

Best regards,
Tim

[anhvulee]

Hi Tim,

I've did some changes like your suggestions and run the simulation again. But the result still remains the same problem.
What should I do now?

[Tim]

Hi,

Wind speed is still only 0.02 m/s at lowest grid cell according to your screenshot. If wind speed is raised for this simulation and on a normal level now, your vertical gridding could be problematic (e.g. Splitting activated while vertical resolution only 1 m).

Best regards,
Tim

[anhvulee]

Hi Tim,

Along this message is my simulation file, Could you please help me to find the problems?
Thanks

[Tim]

Hi,

As I said from the beginning, the wind speed is the problem. Open the FOX file in the Forcing Manager and check the wind speeds for your simulation period. I would not go lower than 1 m/s for any timestep. Disable the Forcing of wind if you don't have better data.

Best regards,
Tim