Thermal boundary layer equation for turbulent Rayleigh-Benard convection etc15 Tracking Number 55Presentation: Session: Thermally driven turbulence 2 Room: Room G Session start: 15:00 Thu 27 Aug 2015 Olga Shishkina Olga.Shishkina@ds.mpg.de Affifliation: Susanne Horn s.horn@imperial.ac.uk Affifliation: Sebastian Wagner Sebastian.Wagner@ds.mpg.de Affifliation: Emily S. C. Ching ching@phy.cuhk.edu.hk Affifliation: Topics: - Wall bounded flows Abstract: We report a new thermal boundary layer equation for turbulent Rayleigh-Benard convection for Prandtl number P>1that takes into account the effect of turbulent fluctuations. These fluctuations are neglected in existing equations, which are based on steady-state and laminar assumptions. Using this new equation, we derive analytically the mean temperature profiles in two limits: Pr~1 and Pr>>1. These two theoretical predictions are in excellent agreement with the results of our direct numerical simulations for Pr=4.38 and Pr=2547.9, respectively. |