The curl of velocity field is defined as vorticity. Vorticity is a microscopic measure of fluid rotation characteristics. ?
Vorticity equation:?
Meaning of each term in vorticity equation:
1)
-Relative vorticity advection change term. This term is caused by the uneven horizontal distribution of relative vorticity, and the rate of change of relative vorticity caused by advection is different from that of the designated place at this point.
2)
-is the vertical advection term of relative vorticity. Due to the vertical distribution of vorticity and the non-uniformity of vertical motion.
3)
-is the meridional advection term of geostrophic vorticity or implicated vorticity. The sign of this term depends on the direction of meridional wind. If the south wind blows, there will be negative geostrophic vorticity advection. If the north wind blows, there is positive geostrophic vorticity advection.
4)
-Divergence term. Horizontal convergence (divergence) will increase (decrease) absolute vorticity, which can be regarded as? Under the condition of conservation, the contraction (expansion) of area increases (decreases) the circulation (vorticity) per unit area. (page 85)
5)
-Force tube project or baroclinic project. This term is caused by atmospheric baroclinic. Because:
six
-To twist. This term indicates that due to the uneven horizontal distribution of vertical velocity, horizontal vorticity is transformed into vertical vorticity, resulting in the change of vertical component of vorticity.