  Turbulence in protoplanetary disks, when present, plays a critical role in
transporting dust particles embedded in the gaseous disk component. When using
a field description of dust dynamics, a diffusion approach is traditionally
used to model this turbulent dust transport. However, it has been shown that
classical turbulent diffusion models are not fully self-consistent. Several
shortcomings exist, including the ambiguous nature of the diffused quantity and
the nonconservation of angular momentum. Orbital effects are also neglected
without an explicit prescription. In response to these inconsistencies, we
present a novel Eulerian turbulent dust transport model for isotropic and
homogeneous turbulence on the basis of a mean-field theory. Our model is based
on density-weighted averaging applied to the pressureless fluid equations and
uses appropriate turbulence closures. Our model yields novel dynamic equations
for the turbulent dust mass flux and recovers existing turbulent transport
models in special limiting cases, thus providing a more general and
self-consistent description of turbulent particle transport. Importantly, our
model ensures the conservation of global angular and linear momentum
unconditionally and implicitly accounts for the effects of orbital dynamics in
protoplanetary disks. Furthermore, our model correctly describes the vertical
settling-diffusion equilibrium solutions for both small and large particles.
Hence, this work presents a generalized Eulerian turbulent dust transport
model, establishing a comprehensive framework for more detailed studies of
turbulent dust transport in protoplanetary disks.
