What Equations Govern This Hypothetical Fluid Flow?

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The discussion revolves around analyzing a hypothetical 2D inviscid potential flow described by a velocity vector, with specific conditions of being steady, uniform, and parallel to a stationary plate. The user contemplates using the Navier-Stokes Equations, noting that the steady state implies time invariance and that inviscid flow suggests zero viscosity. They clarify that parallel flow means no velocity component in the y-direction, while uniform flow indicates spatial consistency in velocity. The user proposes that the equation of motion simplifies to the Laplace equation, leading to the conclusion that both components of velocity must satisfy the condition of being harmonic. Confirmation or further insights on these points are sought to enhance understanding.
member 428835
Hi PF!

I was reading lecture notes from a university and I stumbled on this situation:

We have a hypothetical 2D inviscid, steady, uniform and parallel, potential flow, described by
the velocity vector ## \vec{v} = <u,w>##, with ##u= U[z]## and ##w= W[z]##. It is moving parallel to a stationary plate that lies along the ##x## axis. By “parallel,” it is meant that flow is everywhere parallel to the plate.
By “uniform”, it is meant that the flow is spatially uniform. By “steady”, it is meant that the flow
is time invariant.

When solving for a velocity profile, my first thought was to consult the Navier-Stokes Equations for ractangular coordinates and go from there. What I was thinking was steady implies ##\partial_t = 0##, inviscid implies ##\mu = 0## (or would this be ##\nabla \times \vec{v} = 0##?). Parallel implies ##v_y = 0## where ##y## is orthogonal to the base plate (I think ##u## and ##w## move in the plate direction and from side-to-side respectively (any ideas here)? Potential implies the existence of some scalar ##\phi : \vec{v} = \nabla \phi##. Uniform implies ##\partial_x v = \partial_z v = 0##.

Can someone confirm this?

If I'm right, the equation of motion would simply be ##\nabla ^2 \vec{v} = 0 \implies \nabla^2 u = 0## and ##\nabla^2 w = 0##. Do you agree or disagree?
 
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Thanks for the post! Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
 
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