SolidificationMeltingSource acts different on 2D and 3D

Summary

SolidificationMeltingSource gives different results with 2D and 3D solutions. While 3D solution gives accurate results there is no change in the z direction(3rd direction). So it makes no sense and increases the computational time up to 10 times.

Steps to reproduce

just run buoyantPimpleFoam for test cases I sent. Files also contains some of the results.

Example case

What is the current bug behaviour?

Somehow "Benard Cells" appears in 2D case and it changes melting front drastically.

What is the expected correct behavior?

There should be no "Benard Cells" so melting front will be like 3D case I attached.

Relevant logs and/or images

Environment information

• OpenFOAM version : v2002
• Operating system : ubuntu 18.04
• Hardware info : ryzen 5 3600
• Compiler : gcc

Possible fixes

I have no idea about this.SolidMeltSource.7z