Quote by tatarin
Does it take a lot of time to do integration by using StrattonChu in Comsol?
The only way to speed up the process is by making integration sphere smaller?

With my machine to solve model of 200.000 elements it takes around 35min for 2 step procedure (2 solver runs, GMRES), where StrattonChu integration is part of second solver run, so I imagine it takes less than few minutes, but again depends on number of mesh elements that your sphere is composed of.
Making integration sphere smallerI am not sure. Me and few of my friends are still having some doubts regarding StrattonChu formula and its definition. In RF module guide they say that one should put integration sphere in the
nearfield of your scatterer. That is maybe correct for dielectrics, but for metallic nanoparticles there are strong evanescent fields, so maybe you have to avoid collecting them into StrattonChu. I am not a theoretician so I don't know yet how StrattonChu is really defined, and we are trying to clarify it with COMSOL support at the moment.
So far, I am placing integration sphere on the distance few times larger than evanescent field decaying length, and that is easy for simple structure (spheres, etc....)
ANY DISSCUSSION about interpretation on StrattonChu is welcome here....