Lamb surface

Template:Short description In fluid dynamics, Lamb surfaces are smooth, connected orientable two-dimensional surfaces, which are simultaneously stream-surfaces and vortex surfaces, named after the physicist Horace Lamb. Lamb surfaces are orthogonal to the Lamb vector $\mathit{\omega }\times 𝐮$ everywhere, where $\mathit{\omega }$ and $𝐮$ are the vorticity and velocity field, respectively. The necessary and sufficient condition are

$(\mathit{\omega }\times 𝐮)\cdot [\mathrm{\nabla }\times (\mathit{\omega }\times 𝐮)]=0,\mathit{\omega }\times 𝐮\ne 0.$

Flows with Lamb surfaces are neither irrotational nor Beltrami. But the generalized Beltrami flows has Lamb surfaces.

See also

• Beltrami flow