How to create aligned mesh?

[Saleth-john]

I am trying to create finer mesh inside the bigger coarse mesh region to capture the fire from small burner surface. but I am not able to create aligned mesh. please give some insights to make aligned mesh. Thanks

[Fryfire]

One thing that helps me is sketching out the mesh on physical paper to get a better overview.
What grid size are you using? Would you like to share your input code?

[drjfloyd]

User's Guide
6.3.4 Mesh Alignment

[johodges]

I usually start by separating the mesh into all the regions I want at the coarsest resolution and verify they are aligned. Then I increase the number of cells at the finer meshes. This guarantees alignment so that your fine meshes are not split at a half resolution somewhere.