I’m working with the Matlab code for nonlinear heat transfer in a plate given here: https://www.mathworks.com/help/pde/ug/nonlinear-heat-transfer-in-a-thin-plate.html
I am only dealing with radiation so I set the h coefficient to zero. I would like to apply a boundary condition along one side that is equivalent to 5 Watts of heat entering the plate. How do I convert that to Neumann conditions?