Guilin Sun
Ansys Employee

I am not sure how the refractive index also changes with simulation time.

In general, you will need the simulation run long enough to reach the preset autoshutoff min, which by fault is 1e-5. If the result is suspicious you may need to reduce it further. Please refer this post

Ansys Insight: 透射率反射率大于1,或者透射率反射率之和大于1的原因与解决方案综合贴

 

R+T >1 can be due to a number of reasons: