Dear Vamshi

I do agree with Antoni Artinov

You need a boundary condition on the surface, the top and the bottom of the cylinder.

https://www.sciencedirect.com/search?qs=Thermal%20Flow%20Model%20of%20Comsol&show=25&sortBy=relevance

I think you should put the surrounding environment into the computational domain

Hi Vamshi,

of course you need also a BC on the surface, the top and the bottom of the cylinder. In the most simple case you can just make them thermally unsulated. A second option would be to add convective cooling by giving some coefficient for the heat losses.

Best reagards,

Antoni

Dear Vamshi

I do agree with Antoni Artinov

You need a boundary condition on the surface, the top and the bottom of the cylinder.

Antoni Artinov

Thanks for reply but by default all the surfaces are thermally insulated in comsol

so what extra do I need to add to the model?

I tried giving temperature on total outer surface of cylinder(included with point heat source) as 300K but the result shows no change in temperature. If i exclude the common outer surfaces to point heat source then model shows change in temperature. what to consider

Dear Vamshi Krishna Gondrala

In this file you have some mistakes. This project has two phase of materials (liquid and solid ) and you used "Heat transfer in solid" physic while, you should used "Heat transfer in solid and fluid" physic. Your geometry mesh is coarse. The most importatnt thing is that your fluid and solid have not boundary condition. Generally, you needed another boundary condition. I corrected this mistakes and used of temperature BC in fluid and simulated this project. you can see average temperature of surface in drived values in result box.

Kourosh Vaferi

Thanks for pointing out changes that needs to be done.If I use only copper as material(surface of cylinder) and i don't have any water flowing inside(then i can't use outflow condition) what should be the boundary condition then?