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Qmechanic
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Is there a Lagrangian $L$ (equivalently an action functional $S$) which yields the Navier-Stokes equation?

The Navier-Stokes equation or the Euler equation are usually derived as the conservation laws.

However, I wonder if there exists a Lagrangian $L$ or equivalently, an action functional $S[\overrightarrow{v}]$ of velocity vector fields $\overrightarrow{v}$ which yield the NS / Euler equations as the equation of motion. By the equation of motion, I mean the Euler-Lagrange equation.

Also, is it possible to realize the incompressibility condition $\nabla \cdot \overrightarrow{v}=0$ as a constraint by means of some Lagrange multiplier as well?

Could anyone please provide relevant reference, or the form of such action $S$?