The NavierÂ–Stokes equations reduce to the Euler equations under this condition, which is only exhibited in reality by superfluids.
Under this condition, the Burgers equation becomes a conservation law for kinetic energy density. When this condition holds, a certain biharmonic term vanishes and the Laplacian of the stream function becomes constant in time. Unsteady flows with this property are always hyperbolic rather than parabolic. If this property holds, then one need not impose the noÂ­slip boundary condition, and it is often assumed to hold outside of the boundary layer. The opposite of this type of flow is known as creeping flow. According to (*) d'Alembert's ("dalÂ­ahmÂ­bear's") paradox, if a fluid is incompressible and has this property, then it exerts zero drag on objects moving within it. The NavierÂ–Stokes equations reduce to the Euler equations under this condition, which is only exhibited in reality by superfluids. For 10 points, name this type of fluid where there is no resistance to flow.
Under this condition, the Burgers equation becomes a conservation law for kinetic energy density.
inviscid fluid [accept answers that indicate viscosity is zero; antiÂ­prompt on "superfluidity" until read]