Large-eddy simulation of turbulent heat convection in a spanwise rotating channel flow

Large-eddy simulation of turbulent flows in a heated streamwise rotating channel

“…Owing to the existence of the Coriolis force, large T-G vortices are induced in the core region of the channel, which shift both the mean temperature and mean velocity profiles to the pressure side. Consequently, both the momentum viscous sublayer and the thermal diffusive sublayer become thinner on the pressure side and become thicker on the suction side [14]. Furthermore, in the recent work of Xun et al [39], it was found that the appearance of the T-G vortices causes quasi-periodicity in the spanwise distribution of the drag coefficient and Nusselt number.…”

“…The DNM is based on an explicit nonlinear quadratic tensorial polynomial constitutive relation of Speziale [12], which includes the conventional DM as its first-order approximation as well as two higher-order tensorial constituent components for nonlinear anisotropic representation of the SGS stress tensor. As a result, it can exhibit local stability without the need for plane-averaging, and reflect the physical mechanisms of both forward and backward scatter of SGS KE between the filtered and subgrid scale motions [11,13,14]. In comparison with the DM, the DNM overcomes several major drawbacks of the DM and admits more degrees of freedom for geometrical representation of the SGS stress tensor.…”

“…The Among the studies of turbulent channel flows subjected to these three types of system rotations, the spanwise rotating turbulent channel flows have been studied extensively through experiments [23,24] and numerical simulations [14,[25][26][27][28][29][30][31][32][33][34][35][36][37]. It is reported that as the rotation number increases, turbulence is gradually enhanced on the pressure side and reduced on the suction side, further resulting in asymmetric distributions in the mean flow and Reynolds stresses [14,[23][24][25][26][27][28][29][30][31][32][33][34][35][36][37]. At the same time, large-scale roll cells come forth as a result of the Taylor-Görtler (T-G) instability [14,23,25,35].…”

“…It is reported that as the rotation number increases, turbulence is gradually enhanced on the pressure side and reduced on the suction side, further resulting in asymmetric distributions in the mean flow and Reynolds stresses [14,[23][24][25][26][27][28][29][30][31][32][33][34][35][36][37]. At the same time, large-scale roll cells come forth as a result of the Taylor-Görtler (T-G) instability [14,23,25,35]. These large-scale roll cells dominate the secondary flow pattern in a channel, and shift towards the pressure side.…”

“…Xun et al [14] thoroughly examined the performance of these advanced modelling approaches in the context of a heated rotating channel flow subjected to spanwise rotations. Because both the centrifugal force and the two Coriolis force components are sensitive to the direction of system rotations [53,54], the flow physics in the streamwise and spanwise rotating channel flows are significantly different (the secondary flow is dominated by T-G vortices in a spanwise rotating flow, however, by four opposite stratification layers in a streamwise rotating flow).…”