... Then, let S and Abe the symmetric and antisymmetric parts of (∇πb)π, from (2. 143) it followsthat2D =2nnun,n+ n(ωr× n)+(ωr× n)n +2S, (2. 144) 2 = n(ω ×n) −(ω × n)n +2A, (2. 145)where ... (∇u)T+(∇u)T =2 +(∇u)T,such that2u · Ω = ω ×u, u · (∇u)T= ∇u ·u.Then (2. 11) is cast to the vorticity form, very important in vorticity and vortex dynamics: DuDt=∂u∂t+ ω × u + ∇1 2 q 2 ,q≡|u|. ... velo-city (2. 105). A substitution of (2. 103) then yields (Phillips 1933; Serrin 1959)u =1 2( n − 1)πVϑr + ω × rrndV + B, (3 .27 )where n =2, 3 is the spatial dimension and 2. 4 Splitting and...