Turbulence modulation in dispersed two-phase flow laden with solids from a Lagrangian perspective

In this paper numerical calculations of dispersed particulate two-phase flows, based on the Euler/Lagrange approach, are presented with special emphasis on two-way coupling and turbulence modification. The performance of the Lagrangian consistent terms, including the so-called wake-induced turbulence, that influence the continuous phase turbulent variables in a two-phase flow is compared with the standard terms resulting from the Reynolds average procedure. For this purpose two different gas–solid flow configurations laden with small and large particles are considered, namely an axisymmetric particle-laden jet flow and an upward pipe flow. As a result, the consistent terms are able to reproduce both situations, suppression and enhancement of fluid turbulence for small and large particles, whereas the standard terms can only deal with situations implying turbulence attenuation.