[Radiance-general] Problem with refraction in Dielectric material

[francesco.frontini at polimi.it]

Dear all,
I am running a simulation test to asses if Radiance calculates  
correctly the refraction inside a dielectric material. (Snell law   
n1*sin(A1) = n2sin(A2) ).


I build up two identical geometry one with a dielectric pane and the  
second without. The direct light can pass through a gap between two  
plastic surfaces.


Using just direct calculation (sun) I should have two identical bright  
stripes in dimension but the one passing through the dielectric panel  
should be shifted due to the refraction in the dielectric pane.

I copy and paste down the geometry and the material definition.

I am running the following command:

cat  sensor.grd  |rtrace -h -I -ab 0  test-1.oct  | rcalc -e  
'$1=47.4*$1+120*$2+11.6*$3'  > test-1-sensor1.out

the file sensor.grd is the list of my sensor:

X Y Z  0 0 1

where:

"X" is 2500 (for the case of the dielectric panel) or 7500 (for the  
case without the dielectric panel)

"Y" is changing between 10 and 5000 (with a step of 0.1)

"Z" is 0.01

the simulation results are not clear to me.

--------------

!gensky -ang 45 0 +s



void plastic ConcFlr_Tiles_Suspended


5 	0.576 0.604 0.396   0.0 0.0

void plastic BrickPlaster


5 	0.898 0.898 0.898   0.0 0.0

void dielectric Glass


5 	0.90 0.9 .900   1.520 0.0

Glass polygon zone01.up


15
  	0.0  0.0  5000.0
  	5000.0  0.0  5000.0
  	5000.0  8.0  5000.0
  	0.0  8.0  5000.0
  	0.0  0.0  5000.0

Glass polygon zone01.west


15
  	0.0  0.0  0.0
  	0.0  8.0  0.0
  	5000.0  8.0  0.0
  	5000.0  0.0  0.0
  	0.0  0.0  0.0

Glass polygon zone01.nord


12
  	5000.0  8.0  5000.0
  	5000.0  8.0  0.0
  	0.0  8.0  0.0
  	0.0  8.0  5000.0

Glass polygon zone01.south


12
  	0.0  0.0  5000.0
  	0.0  0.0  0.0
  	5000.0  0.0  0.0
  	5000.0  0.0  5000.0

Glass polygon zone01.est


12
  	5000.0  0.0  5000.0
  	5000.0  0.0  0.0
  	5000.0  8.0  0.0
  	5000.0  8.0  5000.0

Glass polygon zone01.botton


12
  	0.0  8.0  5000.0
  	0.0  8.0  0.0
  	0.0  0.0  0.0
  	0.0  0.0  5000.0

BrickPlaster polygon panel-1a


12
  	0.0  4.0 0.0
  	5000.0  4.0  0.0
  	5000.0 4.0  2450.0
	0.0 4.0  2450.0


BrickPlaster polygon panel-1b


12
  	0.0  4.0 2550.0
  	5000.0  4.0  2550.0
  	5000.0 4.0  5000.0
  	0.0 4.0  5000.0

ConcFlr_Tiles_Suspended polygon zone02.rad00008


15
  	5000.0  8.0  0.0
  	5000.0  10008.0  0.0
  	10000.0  10008.0  0.0
  	10000.0  8.0  0.0
  	5000.0  8.0  0.0

ConcFlr_Tiles_Suspended polygon ceiling


15
  	0.0  8.0  5000.0
  	0.0  10008.0  5000.0
  	10000.0  10008.0  5000.0
  	10000.0  8.0  5000.0
  	0.0  8.0  5000.0

BrickPlaster polygon panel-2a


12
  	5000.0  4.0 0.0
  	10000.0  4.0  0.0
	10000.0 4.0  2450.0
  	5000.0 4.0  2450.0

BrickPlaster polygon panel-2b


12
  	5000.0  4.0 2550.0
  	10000.0  4.0  2550.0
  	10000.0 4.0  5000.0
  	5000.0 4.0  5000.0

ConcFlr_Tiles_Suspended polygon zone02.rad00011


15
  	0.0  8.0  0.0
  	0.0  10008.0  0.0
  	5000.0  10008.0  0.0
  	5000.0  8.0  0.0
  	0.0  8.0  0.0

-----------


Any comment or idea are appreciated

Regards
Francesco