  In Large-Eddy simulation of particle-laden flow, the effect of the unresolved
scales on the particles needs to be modelled. In this work we analyse three
very promising models, namely the approximate deconvolution method (ADM) which
was proposed for particle-laden flow independently by Kuerten (Phys. Fluids 18,
2006) and Shotorban and Mashayek (Phys. Fluids 17, 2005) and two stochastic
models, proposed by Shotorban and Mashayek (J. Turbul. 7, 2006) and Simonin et
al. (Appl. Sci. Res. 51, 1993). We present results from a priori and a
posteriori analysis of these models in isotropic turbulence at Re_lambda=52.
This data allows for a direct quantitative comparison of the models. The
analysis shows that ADM always leads to improved statistics but that even for
high Stokes numbers, the rate of dispersion is not predicted correctly by ADM.
Concerning the stochastic models, we found that with the correct choice of
model parameters, the models perform well at small Stokes numbers. On the other
hand, at high Stokes numbers the stochastic models show significant errors such
that it may be recommendable to neglect the small scale effects instead of
using one of the stochastic models.
