Nanoparticle photothermal therapy modeling

Hello everybody,
With my biology group we're currently creating metallic nanoparticles for photothermal therapy. We're going to measure their heat conversion capacity. I would like to model the heat change in a tumour due to the presence of nanoparticles who a laser has been shined on. However, I do not know how to simulate the presence of nanoparticles. Does anybody have advice on how to do this?

Thank you very much for your help!