We scrutinize an updated version of the non-linear (quadratic) k-ε-ζ-f aiming at sensitizing the model to the effect of rotation. This objective was obtained by imposing that C coefficient depends on the strain and vorticity tensors, the latter explicitly including solid body rotation. The model was tested on plane channel and square-sectioned duct flows. Results are assessed against DNS literature data and properly developed LES computations. We demonstrate that, when considering the channel flows, the developed formulation is able to accurately reproduce flow and turbulent variables at various angular velocity regimes. Good predictions are also obtained for the duct flow, where the flow is subjected to the mutual influence of rotation and near-wall turbulence anisotropy. In particular, the non-linear rotation-sensitized model is able to reproduce the near-wall turbulent kinetic energy distribution close to the suction side, returning a zero value in the mid-span and a small peak close to the vertex on the suction side. Budgets analysis of turbulent kinetic energy demonstrates that the proposed model is able to properly reproduce any of the terms in the k-equation
LES scrutiny of non-linear k-eps-zeta-f model sensitized to rotation / Salvagni, Alessandro; Borello, Domenico; Properzi, E.; Rispoli, Franco. - STAMPA. - (2015), pp. 1-10. (Intervento presentato al convegno 8th International Symposium on Turbulence Heat and Mass Transfer tenutosi a Sarajevo nel 15-18 September 2015).
LES scrutiny of non-linear k-eps-zeta-f model sensitized to rotation
SALVAGNI, ALESSANDRO;BORELLO, Domenico;RISPOLI, Franco
2015
Abstract
We scrutinize an updated version of the non-linear (quadratic) k-ε-ζ-f aiming at sensitizing the model to the effect of rotation. This objective was obtained by imposing that C coefficient depends on the strain and vorticity tensors, the latter explicitly including solid body rotation. The model was tested on plane channel and square-sectioned duct flows. Results are assessed against DNS literature data and properly developed LES computations. We demonstrate that, when considering the channel flows, the developed formulation is able to accurately reproduce flow and turbulent variables at various angular velocity regimes. Good predictions are also obtained for the duct flow, where the flow is subjected to the mutual influence of rotation and near-wall turbulence anisotropy. In particular, the non-linear rotation-sensitized model is able to reproduce the near-wall turbulent kinetic energy distribution close to the suction side, returning a zero value in the mid-span and a small peak close to the vertex on the suction side. Budgets analysis of turbulent kinetic energy demonstrates that the proposed model is able to properly reproduce any of the terms in the k-equationI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.