Firstly make two pipe of different diameters in any cad software, then assemble it in the assembly module. Furthermore, convert into IGES file and then import it into Ansys and give the parting line as the bonded joint. After that, you can go for meshing and analysis.

Thanks for sharing your thoughts,

I want to study the bond strength between those joints.

As Jonty Mago mentions, you must make two different pipes and then proceed with the assembly with restriction of the contact areas.

The finite element analysis depends on the program in which you will perform it due to the configuration in the user interface and analysis of each of them, Ansys is a good option, Nastran also has very good results.

Angelo Oñate

thanks for your response.

How to form mathematical equations for the same?

Raja Varadharaj bro You can use simple ansys to analyze this for that u need two bimetallic pipes of different diameters as the parameters and u can analyze easily ls contact Mr Ebron from PSG Tech- Design lab for further clarifications