Skip to main content
Solved

STAR Module: "No matl. info"


James.Fry
Ultraviolet
Forum|alt.badge.img

I’m using the STAR module and get a “No matl. info” message when I attach FEA data to a surface.  After that, I can’t attach any more data.  Any idea what the issue is here?  FYI, excerpt of thermal FEA data:

-0.196850    0.000000    0.000000    49.041954
-0.139194    0.139194    0.000000    49.042702
-0.072500    0.000000    0.000000    49.692856
-0.072500    0.072500    0.000000    49.590935
0.072500    0.000000    0.000000    49.692856
0.072500    0.072500    0.000000    49.590950

Thanks!

 

Best answer by Sandrine Auriol

Hi @James.Fry and @MichaelH ! Thank you for reporting this.  

Yes a restriction was added on the material catalog. To load thermal datasets, all 6 coefficients need to be defined. But since it is becoming an issue for our customers as they don’t always have access to those coefficients, the product team has decided to roll back the restriction so that if D0 is defined, temperature data can be applied in STAR and will be accepted. It is something that will be available in a coming release. Thank you for your patience.

View original
Did this topic help you find an answer to your question?

3 replies

MichaelH
Ansys Staff
Forum|alt.badge.img+2
  • Ansys Staff
  • 345 replies
  • March 22, 2023

Hey James,

This error message would imply that the GERMANIUM material in the AGF catalog does not have Thermal Coefficients defined.  The default germanium in the INFRARED.AGF catalog only has D0 (linear dn/dT) but doesn’t have any higher order values:

I’m not sure if all 6 Thermal Coefficients are needed for STAR but I would guess you won’t get accurate index values if you don’t have all 6 values defined.

Since this data is provided by the vendors themselves and is not verified by Zemax, I think you’ll have to work with your vendor to provide these values.  The Thermal Coefficients are empirical values which fit the Schott thermal model.


James.Fry
Ultraviolet
Forum|alt.badge.img
  • Author
  • Ultraviolet
  • 33 replies
  • March 22, 2023

Yes, that does appear to be the issue.  If I switch the material to N-BK7, that “error” goes away.  I shall add this to the list of STAR module disappointments.  ☹️  Thanks for the guidance!


Forum|alt.badge.img+2

Hi @James.Fry and @MichaelH ! Thank you for reporting this.  

Yes a restriction was added on the material catalog. To load thermal datasets, all 6 coefficients need to be defined. But since it is becoming an issue for our customers as they don’t always have access to those coefficients, the product team has decided to roll back the restriction so that if D0 is defined, temperature data can be applied in STAR and will be accepted. It is something that will be available in a coming release. Thank you for your patience.


Reply


Cookie policy

We use cookies to enhance and personalize your experience. If you accept you agree to our full cookie policy. Learn more about our cookies.

 
Cookie settings