  We analyzed formation of small-scale inhomogeneities of particle spatial
distribution (particle clustering) in a turbulent flow. The particle clustering
is a consequence of a spontaneous breakdown of their homogeneous space
distribution, and is caused by a combined effect of the particle inertia and a
finite correlation time of the turbulent velocity field. Theory of the particle
clustering is extended to the case when the particle Stokes time is larger than
the Kolmogorov time scale, but is much smaller than the correlation time at the
integral scale of turbulence. The criterion of the clustering instability is
obtained. Applications of the analyzed effects to the dynamics of inertial
particles in industrial turbulent flows are discussed.
