Discussion Forum

I have been trying to simulate the temperature of pulsed laser heating using the Ray Heating Interface (ray optics and heat transfer in solids couplings). It is a multilayer structure on the textured surface of silicon wafer, and we need to consider reflection and refraction, so Beer-Lambert and surface heat source model may not be available. So I chose the Ray heating interface of COMSOL with ray optics and heat transfer in solid and want to get the temperature Vs time. I want to define the pulsed laser power as time-dependent in ray heating source, such as 20 ns. I used an analytic function：exp(-4log(2)((t-3tau)/tau)^2)/(tau(3.14/log(2))^0.5) ,tau is laser pulse duration. This function is used as Total Source Power in Release from Boundary. The heat source power and the temperature can increase but they don't decrease. I don't know how to solve this problem. I appreciate a lot about that. !