SimScale CAE Forum

What is the quickest way to get the Drag Values?


#1

What is the quickest way to get Absolute Force Values(N)(Pressure + Shear) in a particular axis(X,Y, Z and other user defined directions)?

Thanks


#2

Hi @adidavinci,

You can use a Result Control to measure what you need. The example below shows how to measure the total force over an area.

You can view the full project here.

The result is available in the post processor after the simulation is complete. Just hover over the item of interest in the plot to get the value you need.

I hope this helps. Any questions? Please let me know.


#3

@adidavinci - I agree with @BenLewis, that the Result Control Items are probably the fastest way to get them. For flow simulations there is one available called Forces and moments (see screenshot below). Assign it to the faces on which you want the quantitative value of the forces. Once the simulation is over, the forces and moments in all directions + their pressure and viscous components will be available.

The more manual work intensive version is via Paraview, where this blog post might help:

https://www.simscale.com/blog/2014/07/aerodynamics-post-processing/

Best,

David


#4

Hello - Firstly thank you for your reply.

If I understand it correctly, I will get forces in all directions(X, Y and Z). However if I need drag/lift at certain angles to X Y and Z, then where can I derive these from? for ex: in different angle of attack scenarios.

Thanks @dheiny and @BenLewis


#5

Hi @adidavinci

Since you know the angles, just use the simple coordinate transformation from Normal-Axial coordinate ( body axis ) to Lift-Drag coordinates as given in the Lecture Notes from MIT , page2 below:

Or for a reverse transformation see: http://www.aerospaceweb.org/question/aerodynamics/q0194.shtml

Best,
Ali.


#6

Thanks - That was what I was planning on doing. However it would be neat if the platform has a way to quickly extract components of forces!! Is that is in the pipeline by any chance - Thanks!!


#7

@adidavinci, agreed on that one - should be more convenient. We’re working aggressively on a new post-processing environment, that will provide more and more powerful ways of analyzing and visualizing the results. However 3D plot enhancements are right now higher prioritized as 2D ones. So the initial release might not bring what you’re looking for but as the next step, we’ll also provide more capabilities in those 2D plots.


#8

Hello @dheiny - Super - Thanks