The Gravity node adds the force
ρg to the right-hand side of the momentum transport equation. Gravity nodes are mutually exclusive, that is, there can only be one active Gravity node per domain.
Enter the components of the Gravity vector,
g (SI unit: m/s
2). For 2D components the default Gravity vector is defined as
(0, −g_const). Here
g_const is a physical constant equal to 9.8066 m/s
2. For 3D and 2D axisymmetric components, the gravity acts in the negative
z direction by default.