Effect of Particle Volume Fraction on Turbulence in Pipes and Channels

Abstract

It is well known that turbulent channel and pipe flows show subtle differences in flow statistics. Here we investigate the effect of particle loading on the turbulence in these two geometries. We perform direct numerical simulations of both turbulent channels and pipes at Reτ = 180 with St+ = 100 particles. Particle volume fractions of Φf = 2×10-5, 2×10-6 are compared with unladen simulations. Mean flow and turbulence intensities as well as energy spectra are computed along with visual inspection of Q-criterion iso-surfaces. The findings show that in both pipes and channels turbulence intensity is reduced in the inner region but slightly increased in the outer region. The effect being more p..