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ProjectPhysX / FluidX3D

The fastest and most memory efficient lattice Boltzmann CFD software, running on all GPUs via OpenCL. Free for non-commercial use.
https://youtube.com/@ProjectPhysX
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[Question] What is the meanig of flags #26

Closed Yujif1Aero closed 1 year ago

Yujif1Aero commented 1 year ago

Hi,

Thank your for sharing your CFD code. I have a question to your codes. After runing your code, I got the date of flags. I coudnt understand this date. Could you teach me?

Best,

ProjectPhysX commented 1 year ago

Hi @Yujif1Aero, what exactly do you mean with "date of flags"?

Yujif1Aero commented 1 year ago

Thank you for your replying@ProjectPhysX . I couldnt undastand Toggle rendering modes with the keyboard: 1: flags in the section "How to get started?" No.4 of readme file. Is it pysics value?

ProjectPhysX commented 1 year ago

The lbm.flags[n] data field contains an 8-bit integer for every grid point. If it's 00000000, it's a standard fluid voxel, if it's 00000001, it's a solid voxel, if it's 00000010, it's equilibrium boundary (inflow/outflow). The other bits are used for other types.

If you have a voxelized solid geometry in the box, the "flags" rendering mode with key 1 draws the outline of the solid geometry. And it also marks inlet/outlet (equilibrium boundary) voxels and other boundary conditions, if present. These rendering modes are just for visualization, they have no impact on the physics/simulation.