Home > Legacy archive > Specific versions > FARGO-2D1D > **Planet(s) - 1D grid interaction**

Every planet exterts a torque on every ring of the 1D grid, given by the well-known expression of the Lindblad torque density, proportional to , with , where is the radius of the ring, and the radius of the planetary orbit. This is implemented in the procedure `Substep1_1D`

(file `SourceEuler2D1D.c`

).

Reciprocally, every planet recieves the opposite torque from the rings of the 1D grid. This is implemented in `AdvanceSystemFromDisk1D`

(file `Pframforce1D.c`

).

This prescription is only an approximation, and it can’t replace the 2D decription of the planet-disk interactions. The planet should remain sufficiently far away from the grids interface for an accurate simulation.