Modulation of Heat Flux by Inertial Particles Thermal Feedback in a Turbulent Shearless Anisothermal Flow

We analyze the modulation of heat flux by particle thermal feedback in a turbulent shearless flow by employing a recently introduced decomposition of the velocity-temperature correlation in terms of particle velocity and temperature time derivative correlations. The results of a set of Eulerian-Lagrangian point-particle direct numerical simulations (DNSs) at a Taylor microscale Reynolds number equal to 56 and with the same volume fraction is used to reveal the action of thermal feedback in a wide range of thermal Stokes number and Stokes numbers. The results show that particle heat flux is influenced by thermal feedback more than fluid convective heat flux and they act in the opposite way in two-way coupling regime. We also discuss why global particle contribution to the heat flux ratio behave in a certain way and what statistics can attenuate or enhance this ratio under different particle inertia and thermal inertia.