[sisi]

I have a question regarding this tutorial. On page 3 one has to make some adjustments to the constant/polyMesh/boundary file:

We need to change the front and back types to “empty”, so
they should look this after editing:

But how to treat all other boundaries? Should they be left untouched? Please find attached the boundary file...

[alexeym]

Hi,

Yes, you can leave it like this. Though there are faces in defaultFaces patch and it means you've missed certain parts of the mesh during description of the physical groups in Gmsh (and it's hard to imagine where there faces really belong to). Could you post a screen shot of your mesh, marking defaultFaces patch with special colour?

[sisi]

Originally Posted by alexeym

Yes, you can leave it like this. Though there are faces in defaultFaces patch and it means you've missed certain parts of the mesh during description of the physical groups in Gmsh (and it's hard to imagine where there faces really belong to).

So I am still struggeling with the mesh...

Originally Posted by alexeym

Could you post a screen shot of your mesh, marking defaultFaces patch with special colour?

I'm not sure, I got the point. What Do you mean by "defaultFaces patch"? Could I ask you kindly to check the attached geo file!?

[alexeym]

Hi,

(I'll use OpenFOAM terminology: patch == boundary)

In general when you construct a mesh for 2D case, you have 2 patches front and back (or you can make single patch), they have empty type. In your case this is not so (see attached screenshot of your mesh). I.e. you've got front patch which is OK, but your back patch is in fact outlet (or exit).

Your exit patch doesn't exist

    exit
    {
        type            patch;
        physicalType    patch;
        nFaces          0;
        startFace       107946;
    }

top, bottom, inlet, and airfoil patches are OK. And also you've got defaultFaces patch where all non-marked faces went (in fact it should be back patch).

If you keep in mind this fancy naming of the mesh boundaries while setting boundary conditions in 0 folder everything will be OK. But according to your boundary.txt file (attached to the first message) it's not the case.

[alexeym]

Hi,

I've looked through your geo-file, here's corrected definitions of the physical groups:

Physical Surface("inlet") = {31};
Physical Surface("exit") = {39};
Physical Surface("bottom") = {35};
Physical Surface("top") = {27};
Physical Surface("front") = {40};
Physical Surface("back") = {1};
Physical Surface("airfoil") = {19, 23};

and here's boundary file:

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  2.3.0                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      binary;
    class       polyBoundaryMesh;
    location    "constant/polyMesh";
    object      boundary;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

7
(
    back
    {
        type            empty;
        nFaces          43074;
        startFace       64300;
    }
    front
    {
        type            empty;
        nFaces          43074;
        startFace       107374;
    }
    airfoil
    {
        type            wall;
        nFaces          412;
        startFace       150448;
    }
    top
    {
        type            patch;
        nFaces          55;
        startFace       150860;
    }
    inlet
    {
        type            patch;
        nFaces          50;
        startFace       150915;
    }
    bottom
    {
        type            patch;
        nFaces          55;
        startFace       150965;
    }
    exit
    {
        type            patch;
        nFaces          50;
        startFace       151020;
    }
)

// ************************************************************************* //

[sisi]

Thanks for checking the boundary file! Many thanks for your help alexeym! It's working now

[makayasa]

hi alexeym
hi I also have the same problem . after I made ​​a physical group and displayed in parafoam get an error message Can not find an entry for airfoil patchField how do I fix it ?

this p file
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.3.0 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class volScalarField;
object p;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions [0 2 -2 0 0 0 0];

internalField uniform 0;

boundaryField
{
inlet
{
type freestreamPressure;
}

outlet
{
type freestreamPressure;
}

walls
{
type zeroGradient;
}

airfoil
{
type zeroGradient;
}

frontAndBack
{
type empty;
}
}

// ************************************************** *********************** //

[makayasa]

this my geo file
lc = 0.01;

Point(1) = {0, 0, 0, lc};
Point(2) = {0.0005839, -0.0042603, 0, lc};
Point(3) = {0.0023342, -0.0084289, 0, lc};
Point(4) = {0.0052468, -0.0125011, 0, lc};
Point(5) = {0.0093149, -0.0164706, 0, lc};
Point(6) = {0.0145291, -0.02033, 0, lc};
Point(7) = {0.0208771, -0.0240706, 0, lc};
Point(8) = {0.0283441, -0.0276827, 0, lc};
Point(9) = {0.0369127, -0.0311559, 0, lc};
Point(10) = {0.0465628, -0.0344792, 0, lc};
Point(11) = {0.057272, -0.0376414, 0, lc};
Point(12) = {0.0690152, -0.040631, 0, lc};
Point(13) = {0.0817649, -0.0434371, 0, lc};
Point(14) = {0.0954915, -0.0460489, 0, lc};
Point(15) = {0.1101628, -0.0484567, 0, lc};
Point(16) = {0.1257446, -0.0506513, 0, lc};
Point(17) = {0.1422005, -0.0526251, 0, lc};
Point(18) = {0.1594921, -0.0543715, 0, lc};
Point(19) = {0.1775789, -0.0558856, 0, lc};
Point(20) = {0.1964187, -0.057164, 0, lc};
Point(21) = {0.2159676, -0.0582048, 0, lc};
Point(22) = {0.2361799, -0.0590081, 0, lc};
Point(23) = {0.2570083, -0.0595755, 0, lc};
Point(24) = {0.2784042, -0.0599102, 0, lc};
Point(25) = {0.3003177, -0.0600172, 0, lc};
Point(26) = {0.3226976, -0.0599028, 0, lc};
Point(27) = {0.3454915, -0.0595747, 0, lc};
Point(28) = {0.3686463, -0.0590419, 0, lc};
Point(29) = {0.3921079, -0.0583145, 0, lc};
Point(30) = {0.4158215, -0.0574033, 0, lc};
Point(31) = {0.4397317, -0.05632, 0, lc};
Point(32) = {0.4637826, -0.0550769, 0, lc};
Point(33) = {0.4879181, -0.0536866, 0, lc};
Point(34) = {0.5120819, -0.052162, 0, lc};
Point(35) = {0.5362174, -0.0505161, 0, lc};
Point(36) = {0.5602683, -0.0487619, 0, lc};
Point(37) = {0.5841786, -0.0469124, 0, lc};
Point(38) = {0.6078921, -0.0449802, 0, lc};
Point(39) = {0.6313537, -0.0429778, 0, lc};
Point(40) = {0.6545085, -0.0409174, 0, lc};
Point(41) = {0.6773025, -0.0388109, 0, lc};
Point(42) = {0.6996823, -0.03667, 0, lc};
Point(43) = {0.7215958, -0.0345058, 0, lc};
Point(44) = {0.7429917, -0.0323294, 0, lc};
Point(45) = {0.7638202, -0.0301515, 0, lc};
Point(46) = {0.7840324, -0.0279828, 0, lc};
Point(47) = {0.8035813, -0.0258337, 0, lc};
Point(48) = {0.8224211, -0.0237142, 0, lc};
Point(49) = {0.8405079, -0.0216347, 0, lc};
Point(50) = {0.8577995, -0.0196051, 0, lc};
Point(51) = {0.8742554, -0.0176353, 0, lc};
Point(52) = {0.8898372, -0.0157351, 0, lc};
Point(53) = {0.9045085, -0.0139143, 0, lc};
Point(54) = {0.9309849, -0.0105485, 0, lc};
Point(55) = {0.942728, -0.0090217, 0, lc};
Point(56) = {0.9534372, -0.0076108, 0, lc};
Point(57) = {0.9630873, -0.0063238, 0, lc};
Point(58) = {0.9716559, -0.0051685, 0, lc};
Point(59) = {0.9791229, -0.0041519, 0, lc};
Point(60) = {0.9854709, -0.0032804, 0, lc};
Point(61) = {0.990685, -0.0025595, 0, lc};
Point(62) = {0.9947532, -0.0019938, 0, lc};
Point(63) = {0.9976658, -0.001587, 0, lc};
Point(64) = {0.9994161, -0.0013419, 0, lc};
Point(65) = {1, -0.00126, 0, lc};
Point(66) = {1, 0.00126, 0, lc};
Point(67) = {0.9994161, 0.0013419, 0, lc};
Point(68) = {0.9976658, 0.001587, 0, lc};
Point(69) = {0.9947532, 0.0019938, 0, lc};
Point(70) = {0.990685, 0.0025595, 0, lc};
Point(71) = {0.9854709, 0.0032804, 0, lc};
Point(72) = {0.9791229, 0.0041519, 0, lc};
Point(73) = {0.9716559, 0.0051685, 0, lc};
Point(74) = {0.9630873, 0.0063238, 0, lc};
Point(75) = {0.9534372, 0.0076108, 0, lc};
Point(76) = {0.942728, 0.0090217, 0, lc};
Point(77) = {0.9309849, 0.0105485, 0, lc};
Point(78) = {0.9182351, 0.0121823, 0, lc};
Point(79) = {0.9045085, 0.0139143, 0, lc};
Point(80) = {0.8898372, 0.0157351, 0, lc};
Point(81) = {0.8742554, 0.0176353, 0, lc};
Point(82) = {0.8577995, 0.0196051, 0, lc};
Point(83) = {0.8405079, 0.0216347, 0, lc};
Point(84) = {0.8224211, 0.0237142, 0, lc};
Point(85) = {0.8035813, 0.0258337, 0, lc};
Point(86) = {0.7840324, 0.0279828, 0, lc};
Point(87) = {0.7638202, 0.0301515, 0, lc};
Point(88) = {0.7429917, 0.0323294, 0, lc};
Point(89) = {0.7215958, 0.0345058, 0, lc};
Point(90) = {0.6996823, 0.03667, 0, lc};
Point(91) = {0.6773025, 0.0388109, 0, lc};
Point(92) = {0.6545085, 0.0409174, 0, lc};
Point(93) = {0.6313537, 0.0429778, 0, lc};
Point(94) = {0.6078921, 0.0449802, 0, lc};
Point(95) = {0.5841786, 0.0469124, 0, lc};
Point(96) = {0.5602683, 0.0487619, 0, lc};
Point(97) = {0.5362174, 0.0505161, 0, lc};
Point(98) = {0.5120819, 0.052162, 0, lc};
Point(99) = {0.4879181, 0.0536866, 0, lc};
Point(100) = {0.4637826, 0.0550769, 0, lc};
Point(101) = {0.4397317, 0.05632, 0, lc};
Point(102) = {0.4158215, 0.0574033, 0, lc};
Point(103) = {0.3921079, 0.0583145, 0, lc};
Point(104) = {0.3686463, 0.0590419, 0, lc};
Point(105) = {0.3454915, 0.0595747, 0, lc};
Point(106) = {0.3226976, 0.0599028, 0, lc};
Point(107) = {0.3003177, 0.0600172, 0, lc};
Point(108) = {0.2784042, 0.0599102, 0, lc};
Point(109) = {0.2570083, 0.0595755, 0, lc};
Point(110) = {0.2361799, 0.0590081, 0, lc};
Point(111) = {0.2159676, 0.0582048, 0, lc};
Point(112) = {0.1964187, 0.057164, 0, lc};
Point(113) = {0.1775789, 0.0558856, 0, lc};
Point(114) = {0.1594921, 0.0543715, 0, lc};
Point(115) = {0.1422005, 0.0526251, 0, lc};
Point(116) = {0.1257446, 0.0506513, 0, lc};
Point(117) = {0.1101628, 0.0484567, 0, lc};
Point(118) = {0.0954915, 0.0460489, 0, lc};
Point(119) = {0.0817649, 0.0434371, 0, lc};
Point(120) = {0.0690152, 0.040631, 0, lc};
Point(121) = {0.057272, 0.0376414, 0, lc};
Point(122) = {0.0465628, 0.0344792, 0, lc};
Point(123) = {0.0369127, 0.0311559, 0, lc};
Point(124) = {0.0283441, 0.0276827, 0, lc};
Point(125) = {0.0208771, 0.0240706, 0, lc};
Point(126) = {0.0145291, 0.02033, 0, lc};
Point(127) = {0.0093149, 0.0164706, 0, lc};
Point(128) = {0.0052468, 0.0125011, 0, lc};
Point(129) = {0.0023342, 0.0084289, 0, lc};
Point(130) = {0.0005839, 0.0042603, 0, lc};
Point(131) = {1, 0, 0, lc};

Spline(1) = {65, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25};
Spline(2) = {25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1};
Spline(3) = {1, 130, 129, 128, 127, 126, 125, 124, 123, 122, 121, 120, 119, 118, 117, 116, 115, 114, 113, 112, 111, 110, 109, 108, 107};
Spline(4) = {107, 106, 105, 104, 103, 102, 101, 100, 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 89, 88, 87, 86, 85, 84, 83, 82, 81, 80, 79, 78, 77, 76, 75, 74, 73, 72, 71, 70, 69, 68, 67, 66};
Spline(5) = {66, 131};
Spline(6) = {131, 65};
lc = 0.5;
Point(132) = {4, -4, 0, lc};
Point(133) = {4, 4, 0, lc};
Point(134) = {-3, -4, 0, lc};
Point(135) = {-3, 4, 0, lc};
Point(136) = {4, 0, 0, lc};
Point(137) = {-3, 0, 0, lc};
Line(7) = {135, 133};
Line(8) = {133, 136};
Line(9) = {136, 132};
Line(10) = {132, 134};
Line(11) = {134, 137};
Line(12) = {137, 135};
Line(13) = {107, 135};
Line(14) = {25, 134};
Line(15) = {1, 137};
Line(16) = {133, 66};
Line(17) = {131, 136};
Line(18) = {132, 65};
Line Loop(19) = {12, -13, -3, 15};
Plane Surface(20) = {19};
Line Loop(21) = {13, 7, 16, -4};
Plane Surface(22) = {21};
Line Loop(23) = {8, -17, -5, -16};
Plane Surface(24) = {23};
Line Loop(25) = {17, 9, 18, -6};
Plane Surface(26) = {25};
Line Loop(27) = {18, 1, 14, -10};
Plane Surface(28) = {27};
Line Loop(29) = {14, 11, -15, -2};
Plane Surface(30) = {29};
Field[1] = Box;
Background Field = 1;
Transfinite Line {12, 13, 3, 15} = 20 Using Progression 1;
Transfinite Surface {20};
Recombine Surface {20};
Transfinite Line {11, 15, 2, 14} = 20 Using Progression 1;
Transfinite Surface {30};
Recombine Surface {30};
Transfinite Line {7, 16, 4, 13} = 20 Using Progression 1;
Transfinite Surface {22};
Recombine Surface {22};
Transfinite Line {10, 14, 1, 18} = 20 Using Progression 1;
Transfinite Surface {28};
Recombine Surface {28};
Transfinite Line {8, 17, 5, 16} = 20 Using Progression 1;
Transfinite Surface {24};
Recombine Surface {24};
Transfinite Line {9, 18, 6, 17} = 20 Using Progression 1;
Transfinite Surface {26};
Recombine Surface {26};
Extrude {0, 0, 2} {
Surface{20, 22, 24, 26, 28, 30};
Layers{1};
Recombine;
}


Physical Surface(163) = {20, 22, 24, 26, 28, 30};
Back = 163;
Physical Surface(164) = {52, 74, 96, 118, 140, 162};
front = 164;
Physical Surface(165) = {65};
top = 165;
Physical Surface(166) = {139};
bottom = 166;
Physical Surface(167) = {39, 153};
inlet = 167;
Physical Surface(168) = {83, 109};
outlet = 168;
Physical Surface(169) = {47, 161, 73, 131, 117, 91};
airfoil = 169;
Physical Volume(170) = {1, 2, 3, 4, 5, 6};
internal = 170;


/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.3.0 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class polyBoundaryMesh;
location "constant/polyMesh";
object boundary;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

6
(
frontAndBack
{
type empty;
physicalType empty;
nFaces 4332;
startFace 4218;
}
inlet
{
type patch;
physicalType inlet;
nFaces 38;
startFace 8550;
}
airfoil
{
type wall;
physicalType airfoil;
nFaces 76;
startFace 8588;
}
walls
{
type patch;
physicalType wall;
nFaces 38;
startFace 8664;
}
outlet
{
type patch;
physicalType outlet;
nFaces 38;
startFace 8702;
}
defaultFaces
{
type empty;
nFaces 38;
startFace 8740;
}
)

// ************************************************** *********************** //
Thank you for the help....

[alexeym]

@makayasa

And the error message itself? Was not able to find it in your posts.

[makayasa]

I get an error message
" --> FOAM FATAL IO ERROR: Cannot find patchField entry for movingwalls file: /home/yasa/OpenFOAM/yasa-2.3.0/run/naca/0/nut.boundaryField from line 25 to line 43. From function GeometricField<Type, PatchField, GeoMesh>::GeometricBoundaryField::readField(const DimensionedField<Type, GeoMesh>&, const dictionary&) in file /home/opencfd/OpenFOAM/OpenFOAM-2.3.0/src/OpenFOAM/lnInclude/GeometricBoundaryField.C at line 209. FOAM exiting yasa@yasa-X455LD:~/OpenFOAM/yasa-2.3.0/run/naca$

[alexeym]

The error is self-explanatory: you do not have description of movingwalls boundary in 0/nut file. And it is quite strange as I do not see this patch in constant/polyMesh/boundary file.

Still your initial message contradicts with the latest, as initially the error (oh, it helped to re-read the first message) was about airfoil patch, in the latest message it is about movingwalls boundary.

[makayasa]

Hello all. After converting gmsh to foam and I run , why the results in the show is not like the one in the tutorial ? I run simplefoam for airfoil2d case . How do I fix it ? please advise Thank you very much

[makayasa]

hi alexeym Thank you for the advice. Once the problem is solved . Which is a problem now , how to set the angle of attack and velocity on the airfoil without changing the mesh? I use simplefoam for this case Thank you for the help

[alexeym]

Can't you just change magnitude and direction of velocity at the inlet? For O-type grids this is done naturally (using inletOutlet boundary condition), do not know what kind of mesh you have in your geo-file (but since you have got walls patch there, guess airfoil is in some kind of wind tunnel, so the method is not applicable for your case).