Non-physical results with geometric transformations (TransFile)
Opened this issue · 0 comments
The concept behind modifying geometric orientations is documented here, but it does not appear to work.
Here is a MWE example for a scuff-scatter calculation involving two side-by-side spheres. Relevant files are copied below.
Case 1: No TransFile
is used (it is commented out in Args):
Output of the PFT file makes sense (as expected, both spheres have the same absorbed/scattered powers, etc.
# omega surface-label absorbed power (watts) scattered power (watts) ...
1.1 Sphere1 8.085983e-05 9.520283e-03 ...
1.1 Sphere2 8.081348e-05 9.501876e-03 ...
Case 2: A TransFile
displaces both spheres along y:
Spheres.trans
TRANS Default
TRANS 1.0 OBJECT Sphere1 DISP 0 1 0 OBJECT Sphere2 DISP 0 1 0
Output of the PFT file should be the same as Case 1 - this is physically the same configuration. Instead, reported powers are not only different for the two spheres, but negative values show up for Sphere2 (?!)
# omega transform surface-label absorbed power (watts) scattered power (watts) ...
1.1 Default Sphere1 7.719171e-05 9.213488e-03 ...
1.1 Default Sphere2 -5.444921e-04 8.524173e-03 ...
1.1 1.0 Sphere1 7.719171e-05 9.213488e-03 ...
1.1 1.0 Sphere2 -5.444921e-04 8.524173e-03 ...
Does anyone know what is going on here? I tried several different configurations/frequencies (for both regular and abbreviated .trans
file syntax) but the results never seem to make sense.
Relevant files:
Args
ARGS="${ARGS} --geometry Spheres_327.scuffgeo"
ARGS="${ARGS} --Omega 1.1"
ARGS="${ARGS} --TransFile Spheres.trans" # comment out
ARGS="${ARGS} --PFTFile Spheres_327.pft"
ARGS="${ARGS} --pwDirection 0 0 1"
ARGS="${ARGS} --pwPolarization 1 0 0"
Spheres_327.scuffgeo
MATERIAL Gold
wp = 1.37e16;
gamma = 5.32e13;
Eps(w) = 1 - wp^2 / (w * (w + i*gamma));
ENDMATERIAL
OBJECT Sphere1
MESHFILE Sphere_327.msh
MATERIAL Gold
ENDOBJECT
OBJECT Sphere2
MESHFILE Sphere_327.msh
MATERIAL Gold
DISPLACED 2.5 0 0
ENDOBJECT
(Sphere_327.msh is from the solid-sphere
built-in example in scuff-em)