Dear Kolli Harish , it is a bit difficult to answer without knowing your COMSOL model (version, 2D symmetric or 3D?, which models you have been using...) and I am not an expert related to solar receivers.

However, maybe this example, even though just related to temperature simulation, will help you .

First, simulate you model (as you probably have done already). You should get "Study 1" or similar under the Results.

Briefly (see the attachment for more info)

1) Under Results -> Datasets, include Cut Line 3D, choose proper solution and define your cut line.

2) Create 1D Plot Group, and include Line Graph

3) For Dataset, choose this Cut Line you created in the first step

You simply need to define a cut line, depending on what you are looking for and especially where. Is it a line passing through the symmetry plane of the cone? Or is it on the surface?

In the first case you can follow Antti approach, in the second case perhaps the simplest thing to do is to draw a line from your sketch and to assign it as an edge, then plot your solution on it.

Regards