I am trying to set a disc as a volume heat source (radiation) inside a flow simulation by using the volume heat source temperature menu. I want the temperature to be defined radially so that the center is 1093K and the outer edge is 1073K. In the screenshot below, you can see the setup that I put in for F(radius), which seems to show the temperature plot that I am looking for, but after running the simulation I end up with the result on the right. What am I doing wrong?