The convective term of an axisymmetric field in cylindrical form #
On the meridional plane {x₂ = 0} away from the axis, the Cartesian convective term
(u · ∇) u_i of a smooth axisymmetric field is the cylindrical transport term of
eq:aniso:scalar:nse: the radial component picks up the centrifugal term -u_θ²/r, the
swirl picks up u_r u_θ / r, and the vertical component is transported by the meridional
velocity alone. The three identities are the θ-derivative relations of design note R4
inserted into the middle summand; they are pointwise and do not use the equation.
The convective term of the radial component on the meridional plane, off the axis:
u_r ∂_r u_r + u_z ∂_z u_r - u_θ²/r, the left-hand side of eq:aniso:scalar:nse:r without
the time derivative.
The convective term of the swirl on the meridional plane, off the axis:
u_r ∂_r u_θ + u_z ∂_z u_θ + u_r u_θ / r, the left-hand side of
eq:aniso:scalar:nse:swirl without the time derivative.
The convective term of the vertical component on the meridional plane, off the axis:
u_r ∂_r u_z + u_z ∂_z u_z, the left-hand side of eq:aniso:scalar:nse:z without the time
derivative.