[vekh]

Hello,
I'm trying to place volumetric heat source in specified region. My domain extents:
0<x<=0.02
0<y<=0.02
0<z<=0.01
I would like to apply heat source at region:
0.0075<x<0.00125
0.0075<y<0.00125
0.0004<z<0.0005
I wrote condition:

xc=x[0];
yc=x[1];
zc=x[2];
(...)
if ((0.0075<xc<0.00125)&&(0.0075<yc<0.00125)&&(0.0004<zc<0.0005))
{
source = I_0/(3.14*omega*omega);
dS[eqn] = 0.0;
}
else
{
source = dS[eqn] = 0.;
}

The first two conditions (for x and y) works fine, but z condition doesn't work. It's looks like there is no limitation for this dimmension.
Can you help with that problem?

[CeesH]

Hi Vekh,

Wouldn't it be easier to create a separate cell zone in your domain within the mesh, and enable the source term on that location only, if the location is fixed anyway?

Best,
Cees

[upeksa]

I guess you have obtained the coordinates of the cell with the function C_CENTROID. In that case, you will get the coordinates of the cell centroid.
The region you have limited with the z coordinate is very small, so although you have a cell in that area, perhaps you do not have a cell centroid coordinate in it.
You can simply check that with an UDF like "if 0.0004<z<0.0005, C_UDMI = true", and then create an iso-surface and see if any cell is found.

Cheers

[pakk]

Maybe you have to replace

if ((0.0075<xc<0.00125)&&(0.0075<yc<0.00125)&&(0.0004<zc<0.0005))

by

if ((0.0075<xc)&&(xc<0.00125)&&(0.0075<yc)&&(yc<0.00125)&&(0.0004<zc)&&(zc<0.0005))

Mathematically, "0.0075<xc<0.00125" is clear, but for a computer program, "0.0075<xc<0.00125" means "first see if 0.0075 is smaller than xc, and then see if the result of that is smaller than 0.00125".
In other words: if xc is 0.002:
"0.0075<xc<0.00125" is equal to "0.0075<0.002<0.00125" is equal to "(0.0075<0.002)<0.00125" is equal to "FALSE<0.00125" is equal to "0<0.00125" is equal to "TRUE", which is not what you intended.

I am surprised that it gave correct results for x and y, I would expect it to give unwanted results in all three dimensions.