A suspension of heavy Kolmogorov-size spheres suppresses the inertial cascade in homogeneous and isotropic turbulence

The effect of Kolmogorov-size spherical particles on homogeneous and isotropic turbulence is investigated using particle-resolved direct numerical simulations at an unladen Taylor-scale Reynolds number of 150 150 $150$ . Four monodisperse suspensions of particles with identical diameter and volume fraction 10 Superscript negative 3 10 − 3 10⁻³ are considered, while the particle-to-fluid density ratio varies between 100 100 $100$ and 1500 1500 $1500$ and the mass fraction between 0.1 0.1 $0.1$ and 0.6 0.6 $0.6$ . As particle inertia increases, the energy spectrum departs from the canonical Kolmogorov kappa Superscript negative 5 divided by 3 κ − 5 / 3 κ -5/3 scaling and approaches a peculiar regime with kappa Superscript negative 1 κ − 1 κ ⁻¹ , with kappa </jats:inline-gra