Turbulent cascading in Buoyant plumes

This study presents discoveries on the spectral trends of energy cascading in turbulent buoyant plumes. A high-resolution large eddy simulation was used to simulate thermal and buoyant gas plumes. Turbulent plumes have positive helicity throughout the spatial development process. The helicity and turbulent kinetic energy spectra reveal consistent trends and demonstrate a deviation from the classical Kolmogorov’s inertial spectra at high wave numbers. Additional insight into turbulence physics has been confirmed in this study: the forward cascading of energy exists only at higher wavenumbers, whereas the flux of energy and helicity flows from smaller to large-scale structures at the lower wavenumbers.