We consider the stationary
Navier–Stokes equations on a multiply connected bounded domain Ω in ℝn for
n = 2,3 under nonhomogeneous boundary conditions. We present a new sufficient
condition for the existence of weak solutions. This condition is a variational estimate
described in terms of the harmonic part of solenoidal extensions of the given
boundary data; we prove it by using the Helmholtz–Weyl decomposition of vector
fields over Ω satisfying adequate boundary conditions. We also study the
validity of Leray’s inequality for various assumptions about the symmetry of
Ω.
Keywords
stationary Navier–Stokes equations, nonhomogeneous boundary
value problems, Helmholtz–Weyl decomposition