[danielcollins]

Hi all,

I am struggling to discover how to have SU2 output separate data sets for multiple surfaces. For example, I have a cylinder in cross flow. Attached to that cylinder is a flat plate that is aligned so as to be roughly tangent to the surface of the cylinder. In the end, I would like to have 3 data sets: (1) the pressure distribution over the whole system, including cylinder and flap, (2) the pressure distribution on both sides of the flat plate, and (3) the pressure distribution over the cylinder. Another way of looking at it is: I want to find the contributions to lift from the cylinder and plate separately.

I am currently specifying the cylinder surface and the plate surface in the "marker_monitoring" parameter in the configuration file. That gives me total lift, which is only part of what I'm looking for.

Thanks for the help!

[hlk]

Originally Posted by danielcollins

Hi all,

I am struggling to discover how to have SU2 output separate data sets for multiple surfaces. For example, I have a cylinder in cross flow. Attached to that cylinder is a flat plate that is aligned so as to be roughly tangent to the surface of the cylinder. In the end, I would like to have 3 data sets: (1) the pressure distribution over the whole system, including cylinder and flap, (2) the pressure distribution on both sides of the flat plate, and (3) the pressure distribution over the cylinder. Another way of looking at it is: I want to find the contributions to lift from the cylinder and plate separately.

I am currently specifying the cylinder surface and the plate surface in the "marker_monitoring" parameter in the configuration file. That gives me total lift, which is only part of what I'm looking for.

Thanks for the help!

Thanks for your question. Unfortunately this capability is not currently available.
What you can do is to repeatedly run SU2_SOL, which will post-process the solution data and produce the surface plots without re-running the simulation. You would just need to change the value in MARKER_PLOTTING each time, and you make sure that you have the right restart file under the right name (usually restart_flow.dat - if SU2_SOL cannot find the file it is expecting, it will print an error saying what the file name ought to be). This will overwrite suface_flow.dat each time, unless you change SURFACE_FLOW_FILENAME in the config file.

[danielcollins]

Thank you, hlk. That helps enormously.

[giovanni.medici]

I know this is an old post, but I'd like to know whether this feature (monitoring of the contribution in force and moments of each surface), has been added in the recent releases of SU2.

I wonder whether there is a snippet or python script available to perform what hlk kindly suggested, programmatically.

Thanks!

[giovanni.medici]

I answer to my own question as maybe also other users missed this native function in SU2 (tested in 7.1.0).
In order to have a report of the Forces (total, pressure and friction) and moment coefficients, of the zones (so to have a breakdown of the forces for each surface).

It is as easy as adding to your cfg file the lines below:

% Output file with the forces breakdown
BREAKDOWN_FILENAME= forces_breakdown.dat

WRT_FORCES_BREAKDOWN= YES

Thanks to this post for providing me the right clue!

[imech_origin]

Originally Posted by danielcollins

Hi all,

I am struggling to discover how to have SU2 output separate data sets for multiple surfaces. For example, I have a cylinder in cross flow. Attached to that cylinder is a flat plate that is aligned so as to be roughly tangent to the surface of the cylinder. In the end, I would like to have 3 data sets: (1) the pressure distribution over the whole system, including cylinder and flap, (2) the pressure distribution on both sides of the flat plate, and (3) the pressure distribution over the cylinder. Another way of looking at it is: I want to find the contributions to lift from the cylinder and plate separately.

I am currently specifying the cylinder surface and the plate surface in the "marker_monitoring" parameter in the configuration file. That gives me total lift, which is only part of what I'm looking for.

Thanks for the help!

Have you found a way to output data for each surface without rerunning your simulation?

[bigfootedrockmidget]

If what you are interested in is the lift and drag on individual surfaces, then you can add the marker names of the surfaces to MARKER_MONITORING and in the HISTORY_OUTPUT you say that you want to have LIFT_ON_SURFACE. This option below will give you the lift and drag of the individual surfaces as well as the total lift and drag:

MARKER_MONITORING= CYLINDER, FLAP
HISTORY_OUTPUT= LIFT, DRAG, LIFT_ON_SURFACE, DRAG_ON_SURFACE

Or use

HISTORY_OUTPUT= AERO_COEFF_SURF, FLOW_COEFF_SURF

for all fields in these groups

The lift and drag found in history.csv should be the same as what you can find with in forces_breakdown with the option

WRT_FORCES_BREAKDOWN= YES