SimScale CAE Forum

Sign Convention in CFD

I performed a external flow analysis of an UAV, the results plot, I am not sure of pressure moment sign convention, because the model change its orientation from solid works when I uploaded in to simscale
Can any one help me with this?
Thanks in advance

Check the final orientation of your model … and make sure to share your project or post images to give us an idea of the results and model orientation

Thank you for your reply
the following image shows the orientation of model

the following image shows the result plot of pressure moments

I want to know the rotational direction of pressure moment. is the plane gonna pitch up or
pitch down, yaw to right or left
and which pressure moment (x, y,z) of the is connected to which action of plane (pitch , roll, yaw)

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Well, to determine if your airplane is gonna pitch upwards or downwards, the pressure moment may help you, however, it depends where you set the center of rotation, as SimScale integrates all the pressure forces around that particular point (check out this link: Forces and Moments | Result Control | SimScale Documentation) . As you know, you should set that point in the longitudinal position of the CG.

However, I am not liking the fact that the results do not appear to be converged. I am not sure if the simulation blew after the 800th iteration, but such variation of the values should not occur. Can you please post the velocity, pressure and turbulence convergence plots?

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