I have plotted Heinert's analytical solution for TR noise using Duan's parameters. Since TO and TE noise can be found by simply rescaling TR noise, these have been included in the plot as well. The solid curve represents the analytical solution, while the tick marks represent COMSOL's solution. I have used COMSOL for both a 1D axisymmetric and a 3D model. Since Duan's cylinder has a radius of 125 microns, but a length of 1 m, the meshing was difficult for the 3D model. I ended up shortening the length of the cylinder, converting to the actual length when finally calculating the thermal noise.