[CFD-Lover]

Hi Foamers,

I have recently installed Dakota to be applied to some interesting cases that I created for my project. All grids were created using Gmsh. However, I don't really know whether I will be able to preform shape parametrization and moving mesh for grids generated using Gmsh as well as Dakota's capabilities to handle meshes generated using Gmsh. I need to use Dakota to optimize NACA0012 airfoil type just for verifications. Has anyone done any similar optimizations could bring up to speed.

Thanks in advance,

Best,

[Dipsomaniac]

Hello

A great place to start with the coupling of OpenFOAM and Dokata is the tutorial from Wolf Dynamics, linked below

http://www.wolfdynamics.com/tutorials.html?id=46

It has the case setup and an extensive presentation attached to it.

Cheers,
Brian

[CFD-Lover]

Many thanks Brian for the valuable link! I will spend some time reading and following the case file and let you know how it goes with me!

Thanks Again,

[CFD-Lover]

Hi Brian,

I have got the case files from the link that you suggested. However, there weren't enough information on how do you run the NACA airfoil case. Have you run that case before? Could you please walk me though?

Thanks in advance,

[Tobi]

Just want to give you more information (if you ever used the search function, you would find them too):

http://openfoamwiki.net/index.php/Si...l_Optimization

http://openfoamwiki.net/index.php/Howto_DAKOTA_OpenFOAM (Section 1.3)

https://www.cfd-online.com/Forums/op...-tutorial.html

https://www.cfd-online.com/Forums/op...-tutorial.html

http://www.holzmann-cfd.de/index.php/en/dakota-coupling

And of course the link provided above (that you already checked out).

[CFD-Lover]

Hi Topi,

Many thanks for the massive links. These links will definitely make me so busy. I am currently facing some issues getting the following case to work http://www.mediafire.com/file/72dtp6...ultidim.tar.gz. Would be possible to walk me through if you got some time.

Thanks in advance,

[Tobi]

Hi,

I could check the case but I have no time for that (sorry). But instead, you can check my cases (last link). Here, I provided a run script and everything works well. Good luck.

[CFD-Lover]

Thanks again.

Best,

[CFD-Lover]

Hi,

I just downloaded the case the you suggested but it didn't work following the Read-me file. I am using OpenFoam v2.3.1.

Thanks,

[linnemann]

Hi

Just my two cents from using Dakota.

Much easier to get running with Pyopt http://www.pyopt.org/

I have made a simple tutorial here https://github.com/nelinnemann/openf...m/pyOpt-2D-car

[akidess]

In your tutorial you selected NSGA2 as your optimizer - would you recommend this as a good choice for this class of problems, or did you select it without much thought put into it?

[CFD-Lover]

I do appreciate all your help and hospitality guys, but I am still unable to run Tobi's case for some reason.

Nails! thank you for the alternative optimizations tool, I will double check PyOpt.

Thank you all.

[Tobi]

My case is build for FOAM-4.x. What error do you get and which tutorial did you check out?

[CFD-Lover]

I have tried to run the case "dakotaOpenFOAMCouplingSamplingLHS.tar.gz".

When I ran ./createMesh, I got the following error;

    From function blockMesh
    in file blockMeshApp.C at line 137.

FOAM exiting

   - Rotate baffles
./createMesh: line 29: system/rotateBaffles: No such file or directory
   - Adding baffles to the mesh


--> FOAM FATAL ERROR: 
Cannot find file "points" in directory "polyMesh" in times 0 down to constant

    From function Time::findInstance(const fileName&, const word&, const IOobject::readOption, const word&)
    in file db/Time/findInstance.C at line 203.

FOAM exiting

   - Flatten mesh


--> FOAM FATAL ERROR: 
Cannot find file "points" in directory "polyMesh" in times 0 down to constant

    From function Time::findInstance(const fileName&, const word&, const IOobject::readOption, const word&)
    in file db/Time/findInstance.C at line 203.

FOAM exiting

   - Extrude one patch to make a 2D mesh again


--> FOAM FATAL ERROR: 
Cannot find file "points" in directory "polyMesh" in times 0 down to constant

    From function Time::findInstance(const fileName&, const word&, const IOobject::readOption, const word&)
    in file db/Time/findInstance.C at line 203.

FOAM exiting

   - Remove not necessary boundarys


--> FOAM FATAL ERROR: 
Cannot find file "points" in directory "polyMesh" in times 0 down to constant

    From function Time::findInstance(const fileName&, const word&, const IOobject::readOption, const word&)
    in file db/Time/findInstance.C at line 203.

FOAM exiting

   - Copy 0.org to 0
rm: cannot remove ‘0’: No such file or directory
   - Renumber the mesh


--> FOAM FATAL ERROR: 
Cannot find file "points" in directory "polyMesh" in times constant down to constant

    From function Time::findInstance(const fileName&, const word&, const IOobject::readOption, const word&)
    in file db/Time/findInstance.C at line 203.

FOAM exiting

When I did ./run, I got the following error;

    From function blockMesh
    in file blockMeshApp.C at line 137.

FOAM exiting



--> FOAM FATAL ERROR: 
Cannot find file "points" in directory "polyMesh" in times 0 down to constant

    From function Time::findInstance(const fileName&, const word&, const IOobject::readOption, const word&)
    in file db/Time/findInstance.C at line 203.

FOAM exiting



--> FOAM FATAL ERROR: 
Cannot find file "points" in directory "polyMesh" in times 0 down to constant

    From function Time::findInstance(const fileName&, const word&, const IOobject::readOption, const word&)
    in file db/Time/findInstance.C at line 203.

FOAM exiting



--> FOAM FATAL ERROR: 
Cannot find file "points" in directory "polyMesh" in times 0 down to constant

    From function Time::findInstance(const fileName&, const word&, const IOobject::readOption, const word&)
    in file db/Time/findInstance.C at line 203.

FOAM exiting



--> FOAM FATAL ERROR: 
Cannot find file "points" in directory "polyMesh" in times 0 down to constant

    From function Time::findInstance(const fileName&, const word&, const IOobject::readOption, const word&)
    in file db/Time/findInstance.C at line 203.

FOAM exiting

rm: cannot remove ‘0’: No such file or directory


--> FOAM FATAL ERROR: 
Cannot find file "points" in directory "polyMesh" in times constant down to constant

    From function Time::findInstance(const fileName&, const word&, const IOobject::readOption, const word&)
    in file db/Time/findInstance.C at line 203.

FOAM exiting

   |--> Start stimulation


--> FOAM FATAL ERROR: 
Cannot find file "points" in directory "polyMesh" in times 0 down to constant

    From function Time::findInstance(const fileName&, const word&, const IOobject::readOption, const word&)
    in file db/Time/findInstance.C at line 203.

FOAM exiting

./dakota.sh: line 99: postProcess: command not found
./dakota.sh: line 101: postProcess: command not found
cat: postProcessing/Taverage/0/surfaceRegion.dat: No such file or directory
cp: cannot stat ‘constant/polyMesh’: No such file or directory
cp: cannot stat ‘clean/*’: Not a directory
(standard_in) 2: syntax error
(standard_in) 2: syntax error
   |--> Minimum Temperature at outlet is: 
   |--> Maximum Temperature at outlet is: 
   |--> Average Temperature at outlet is: 
   |--> Angle of baffle is: 
   |--> Function for dakota (Average) is: 
   |--> Function for dakota (Distribution) is: 
   |
Error(s) encountered reading results file results.out for Evaluation 1:
-- Expected 2 function value(s) but found 0.
   - DAKOTA analyzes successfully ended

I am using OpenFoam 2.3.1. Could this be the issue?

Thanks in advance,

[Tobi]

Yes, the case is build for Foam 4.x as you can see in the output of the run script.

-------------------------------------------------------------------------------
Tutorial by Tobias Holzmann
Generated October 2016  
OpenFOAM-4.x
DAKOTA
Tested with Ubuntu 16.04

Unfortunately this tutorial does not have the latest checks (like in all other tutorials). So either you switch to Foam 4.x or you have to change everything in order to use foam 2.3.1.

[CFD-Lover]

Originally Posted by Tobi

or you have to change everything in order to use foam 2.3.1.

Thanks again for the quick response. With regard to the quoted sentence, what do I need to change in order to make work in version 2.3.1.

Thanks again,

[linnemann]

Originally Posted by akidess

In your tutorial you selected NSGA2 as your optimizer - would you recommend this as a good choice for this class of problems, or did you select it without much thought put into it?

I'm not an optimization algorithm guy, but have read ok things about NSGA2.
It works fine for this problem and produced fine results.