  An analytical model for a turbulent clumpy gas disk is presented where
turbulence is maintained by the energy input due to supernovae. Expressions for
the disk parameters, global filling factors, molecular fractions, and star
formation rates are given as functions of the Toomre parameter $Q$, the ratio
between the cloud size and the turbulent driving length scale $\delta$, the
mass accretion rate within the disk $\dot{M}$, the constant of molecule
formation $\alpha$, the disk radius, the angular velocity, and its radial
derivative. Two different cases are investigated: a dominating stellar disk and
a self-gravitating gas disk in $z$ direction. The turbulent driving wavelength
is determined in a first approach by energy flux conservation, i.e. the
supernovae energy input is transported by turbulence to smaller scales where it
is dissipated. The results are compared to those of a fully gravitational
model. For Q=1 and $\delta=1$ both models are consistent with each other. In a
second approach the driving length scale is directly determined by the size of
supernovae remnants. Both models are applied to the Galaxy and can reproduce
its integrated and local gas properties. The influence of thermal and magnetic
pressure on the disk structure is investigated. We infer $Q \sim 1$ and
$\dot{M} \sim 0.05 - 0.1 M_{\odot} yr ^{-1}$ for the Galaxy.
