Turbulence characteristics of the Bödewadt layer in a large shrouded rotor-stator system

Sébastien Poncet (1) , Anthony Randriamampianina (1)

1 IRPHE - Institut de Recherche sur les Phénomènes Hors Equilibre

A three-dimensional direct numerical simulation (3D DNS) is performed to describe the turbulent flow in an enclosed rotor-stator cavity characterized by a large aspect ratio $G=(b-a)/h=18.32$ and a small radius ratio $a/b=0.15$ ($a$ and $b$ the inner and outer radii of the rotating disk and $h$ the interdisk spacing). Recent comparisons with velocity measurements have shown that, for the rotational Reynolds number $Re=\Omega b^2/\nu=95000$ ($\Omega$ the rate of rotation of the rotating disk and $\nu$ the kinematic viscosity of water) under consideration, the stator boundary layer is 3D turbulent and the rotor one is still laminar. Budgets for the turbulence kinetic energy are here presented and highlight some characteristic features of the effect of rotation on turbulence. A quadrant analysis of conditionally averaged velocities is also performed to identify the contributions of different events (ejections and sweeps) on the Reynolds shear stress.

Mots clés: Three-dimensional turbulent boundary layer; Direct Numerical Simulation; LDA; rotor-stator flow

Domaines: Mécanique des fluides [physics.class-ph]; Mécanique des fluides [physics.class-ph]

Sébastien Poncet, Anthony Randriamampianina. Turbulence characteristics of the Bödewadt layer in a large shrouded rotor-stator system. Conference on Turbulence and Interactions TI2006, 2006, Porquerolles, France. ⟨hal-00085153⟩