Experimental and numerical investigation of turbulent natural convection in a large air-filled cavity

We investigate experimentally and numerically the turbulent natural convection flow that develops in a differentially heated cavity of height H=1 m, width W=H and depth D=0.32H, submitted to a temperature difference between the active vertical walls equal to 15 K resulting in a characteristic Rayleigh number equal to 1.5 × 109. In the experiment temperature is measured by 25 μm micro-thermocouples and velocity by a Laser Doppler Anemometer. Both 2D and 3D LES and 3D DNS are performed. DNS uses a Chebyshev spectral method and LES a finite volume method with a local subgrid diffusivity model. Numerical simulations are performed for both adiabatic conditions and experimentally measured temperature on the horizontal walls. Time-averaged quantities and turbulent statistics in the median vertical plane are presented and compared.