Set the computational domain

Define the axis-aligned box that contains the simulation’s fluid and components.

Define the bounds

Choose axes that make cuboids and boundary faces straightforward to describe. Set origin to the minimum x, y, and z coordinates and size to the positive extent in each direction:

"domain": {
  "origin": [0.0, 0.0, 0.0],
  "size": [0.3, 0.2, 0.1],
  "boundary_conditions": []
}

Keep all dimensions in meters and every component inside these bounds. If buoyancy is enabled, set gravity consistently with the chosen axes rather than assuming z is always vertical.

Place exterior boundaries

Conditions in domain.boundary_conditions select axis-aligned patches on the six exterior faces. A boundary that belongs inside the domain must instead lie on an insulating cuboid face. Choose the domain axes so required openings can use these faces.

Verify the domain

Run a dry run and inspect the fluid and solid regions to confirm that intended passages remain connected. Resolve any errors involving boundary regions returned by the API.

See also

• Geometry and the computational domain explains the region model.
• Configure the mesh explains how to control cell sizes within the domain.