Transition on local temperature fluctuations in highly turbulent convection

作     者：Gauthier, F. Salort, J. Bourgeois, O. Garden, J. -L. du Puits, R. Thess, A. Roche, P. -E. 

作者机构：UJF CNRS Inst Neel F-38042 Grenoble 9 France Tech Univ Ilmenau D-98693 Ilmenau Germany 

出 版 物：《EPL》 (欧洲物理学快报)

年 卷 期：2009年第87卷第4期

页      面：44006 (6pp-44006 (6pp页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

基　　金：Region Rhone-Alpes Procope program [17858YD, D/0707571] Deutsche Forschungsgemeinschaft [TH 497/22-1] 

主　　题：Turbulent convective heat transfer Heat transfer: Natural convection Instrumentation and measurement methods in fluid dynamics 

摘      要：In 1997, a new turbulent regime has been observed in a Rayleigh-Benard cell and has been interpreted as the Ultimate Regime of convection. This observation was based on global heat transfer measurements at very high Rayleigh numbers (Ra). Using a set-up similar to the one used in 1997, we examine the signature of this regime from within the flow itself. A systematic study of probe-size corrections shows that the earlier local temperature measurements within the flow were altered by an excessive size of thermometer, but not according to a theoretical model proposed in the literature. Using a probe one order of magnitude smaller than the one used previously, we find evidence that the transition to the very-high-Ra regime is indeed accompanied with a clear change in the statistics of temperature fluctuations in the flow. Copyright (C) EPLA, 2009