[Bernoulli666]

Hi,
I am trying to plot runtime Cl and Cd coefficients with pyFoam. I know that I have to create a customRegExp file but I don't know exactly how to do it. My attempt is:
forceCoeff
{
expr "Cd : (%f%) pressure: (%f%) viscous: (%f%) ";
name forceCoeff;
theTitle "Force Coefficients over simulation time";
titles (
"Drag coeffcient"
);
type regular;
grid on;
autoscale;
}


and my log file is like this:

Time = 2

DILUPBiCG: Solving for Ux, Initial residual = 0.002869770138220821, Final residual = 0.0001357318528722006, No Iterations 1
DILUPBiCG: Solving for Uz, Initial residual = 0.003088079211852372, Final residual = 0.0001757611794099855, No Iterations 1
DICPCG: Solving for p, Initial residual = 0.004518101709886009, Final residual = 4.425545073399058e-05, No Iterations 257
DICPCG: Solving for p, Initial residual = 6.484914641014207e-05, Final residual = 9.938644410614112e-07, No Iterations 220
time step continuity errors : sum local = 1.826300588277174e-07, global = 4.836550994773706e-10, cumulative = 1.448013136733958e-08
DILUPBiCG: Solving for omega, Initial residual = 0.2379849598823938, Final residual = 0.002890402057918726, No Iterations 1
DILUPBiCG: Solving for kl, Initial residual = 0.02000845435751553, Final residual = 0.0003626628549138197, No Iterations 2
bounding kl, min: -6.263186930189056e-12 max: 0.04597626869321963 average: 0.0005251168972862916
DILUPBiCG: Solving for kt, Initial residual = 0.2069146957936084, Final residual = 0.007573494860198234, No Iterations 1
bounding kt, min: -0.0001182717858011264 max: 0.005188559021131677 average: 0.001791225448621331
ExecutionTime = 3.2 s ClockTime = 3 s

forceCoeffs forcesCoeff execute:
Coefficients
Cm : 16.19597892918553 (pressure: 16.18687635895121 viscous: 0.009102570234321211)
Cd : 11.40483349113927 (pressure: 10.83725883229526 viscous: 0.5675746588440076)
Cl : 30.13976085852525 (pressure: 30.27620377857635 viscous: -0.1364429200511035)
Cl(f) : 31.26585935844816
Cl(r) : -1.126098499922907

forces Forces write:
Sum of forces
Total : (15598.51043114574 -2.692622858846829e-17 155547.3987531071)
Pressure : (12767.67376730014 -1.127114060582343e-16 155474.1214542766)
Viscous : (2830.836663845591 8.578517746976596e-17 73.27729883055481)
Sum of moments
Total : (-77773.69937655356 -78567.80939347015 7799.255215572868)
Pressure : (-77737.06072713828 -78523.65219826213 6383.836883650072)
Viscous : (-36.63864941527739 -44.15719520800762 1415.418331922795)
Does anybody know where is my error?
Thank you

[floquation]

You should compare your expression character-by-character with your Cd-line in your log file.
You'll readily notice that you miss brackets: "(" before "pressure" and ")" after the viscous number.

[Bernoulli666]

Originally Posted by floquation

You should compare your expression character-by-character with your Cd-line in your log file.
You'll readily notice that you miss brackets: "(" before "pressure" and ")" after the viscous number.

I read in this post (https://www.cfd-online.com/Forums/op...tomregexp.html) that brackets cause errors. By the way, I tried also with brackets and it still doesn't work.

[floquation]

Brackets are not really a problem, as long as you deal with them as you're supposed to deal with them in regular expression.
This was also described in the next post in your link.

If you want a bracket "(", you should write "\(". Othewise "(" is interpreted as the start of a group; but you really mean a bracket, hence you need the "\" escape character.

[Bernoulli666]

I used \ as you suggested but it still doesn't work. My expr now is:

expr "Cd : (%f%) \(pressure: (%f%) viscous: (%f%)\)"

[Bernoulli666]

I found the error. I added

binData
{
nBin 90; // output data into 20 bins
direction (1 0 0); // bin direction
format gnuplot;
cumulative yes;
}

in my object function and now it works. Thank you for your help floquation.

[Bernoulli666]

I have one more question. Is it possible to change the range of my Cd and Cl plots? I used the option autoscale, I don't know how to select a range.

[Elham]

Hi,


It seems strange but I cannot see customRegexp file in my case directory when I execute the following:

pyFoamRunner.py --progress --proc=11 interMixingFoam

or

pyFoamRunner.py mpirun -np 11 interMixingFoam -parallel >log.pyFoamRunner

I use OpenFOAM2.3.1.


Cheers,


Elham