A Large Eddy Simulation (LES) study to capture turbulence attenuation for turbulent channel flows*

The presence of particles leads to turbulence modulation in particle-laden turbulent flows. In the present study, turbulence attenuation is observed with Smagorinsky and dynamic Smagorinsky models for two Reynolds numbers of 3300 and 5600 based on average gas velocity and channel width. The turbulence intensities decrease with an increase in particle loading, after a critical loading (CPVL) a sudden drop in the fluid fluctuations is observed. At low volume fractions, LES models predict the turbulence attenuation with high accuracy (> 80%) but fail to predict the volume loading at which turbulence collapse happens. It is found that an inaccurate prediction of the turbulent energy production is the source of error in CPVL prediction which is caused by the “modeling error” in LES models.