  We discuss the problem of an effective descriptions of the phase transition
phenomena in the pure gluodynamics in SU(2) symmetric QCD. We choose the method
of calculation following the conjecture that the infrared sector of the theory
possesses the same confinement characteristic as the full theory. We show, that
analytic descriptions of this phenomena is beyond the Gaussian method of
evaluations of functional integrals. We propose a non-perturbative evaluation
of functional integral, meanwhile for two dimensional Wiener integral for
$\phi^4$ theory.
