Particle clustering in radiation-induced turbulence

In the context of flows laden with inertial particles, we explore a novel regime, in which turbulence is sustained solely by the thermal radiation absorbed by the dispersed phase. When a fluid laden with particles is subject to radiative flux, non-uniformities in particle distribution result in local temperature fluctuations. Under the influence of gravity, buoyancy induces the vortical fluid motion leading to higher non-uniformities of inertial particles. From numerical simulations it is shown that the feedback loop between the local particle concentration, the temperature fluctuations and the convective motion can create and sustain turbulence. When the particle response time is comparable to the temporal scales of the flow, the system exhibits intense fluctuations of turbulent kinetic energy associated to the high intermittency of the particle concentration.