Boundary conditions of scalar for pipe flow

[Madhurjya814]

Hi,
What is the boundary condition for pipe flow case. Is it a constant temperature or constant wall heat flux condition? Can you explain the line of the subroutine boundary_conditions_pipe?

[mathrack]

Hello,

This subroutine is available if you need case-specific boundary conditions. The situation is similar here : https://github.com/xcompact3d/Incompact3d/blob/master/src/Case-TGV.f90#L110

Cheers,
Mathrack

[Madhurjya814]

Thanks. Can you help me in giving constant wall temperature boundary condition for the pipe flow case?

[mathrack]

For the pipe flow, the boundary condition at the pipe wall is imposed using the immersed boundary technique. See ibm.f90

Boundary conditions are imposed at the reconstruction stage. Reconstruction is performed each time a derivative needs to be computed. See derive.f90

Derivatives are needed to solve the transport equation for the momentum and the scalars. See transeq.f90

I think the default imposed value for the scalar is zero. It is similar for all velocity components.

[Madhurjya814]

Hi, can you tell me what the following subroutine does? Is it for mixed convection case?

[mathrack]

Hello,

There is no need for a screenshot, you can simply provide a link to a specific line in the code : https://github.com/xcompact3d/Incompact3d/blob/master/src/transeq.f90#L720

For your question : yes, the subroutine momentum_gravity will update the momentum rhs to take into account the buoyancy effect.

[mathrack]

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