Abstract: The rotational dynamics of small anisotropic material particles, e.g., fibres or disks, in developed turbulent flows has attracted increasing attention in recent years. State-of-the-art experiments as well as numerical simulations have revealed complex behaviours which are inherited from the non-trivial dynamics of small scale turbulent structures. For exemple, the observed dependency of tumbling rate at varying the particle shape has been convincingly connected to the preferential alignment of particles with the intrinsic orientations of the fluid velocity gradient tensor in turbulent conditions.
While the phenomenology of orientations in homogeneous and isotropic turbulent flows for simple in shape particles has been carefully inspected, less explored remains the case of non-ideal turbulent flows as well as the instance of less idealized particles. In this talk I will present a series of recent numerical and experimental studies on the anisotropic particle dynamics in turbulence. First, I will address the case of particles in a turbulent convective flow, i.e. in a flow environment which is both statistically inhomogeneous and anisotropic. Second, I will extend the study to the case of particles with non-homogeneous mass in the same environment. I will conclude with remarks on the implications of these findings for the modelling of the dynamics of sensing and motile micro-organisms in turbulent environments.