  We investigate the three dimensional compressible Navier-Stokes and the
continuity equations in Cartesian coordinates for Newtonian fluids. The
polytropic equation of sate is used as closing condition. The key idea is the
three-dimensional generalization of the well-known self-similar Ansatz which
was already used for non-compressible viscous flow in our former study (Commun.
in Theor. Phys. 56, (2011) 745). In the second method the three dimensional
traveling wave Ansatz was applied. The geometrical interpretations of the trial
functions are also discussed.
