The elusive 'ultimate state' of thermal convection
Article Abstract:
Turbulence effects become independent of viscosity when the Reynolds number is large enough. Dimensionless analysis can give several dimensionless numbers to estimate scaling laws, and the Reynolds umber is defined by Re = UL/v for a fluid kinematic viscosity v, flowing with speed U past a body of size L. Glazier and colleagues have reached regimes with thermal boundary layer exceeding the viscous one, although there is still a good fit with the 2/7 law, and no evidence for heat flux or turbulence structure changes. The expected ultimate regime could be a chimaera, and this contradicts earlier claims of a mercury transition.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1999
User Contributions:
Comment about this article or add new information about this topic:
Observation of an internal wave attractor in a confined, stably stratified fluid
Article Abstract:
The response of a confined, stably stratified fluid over a wide range of vibration frequencies is determined by internal-wave attractors, not eigenmodes. It would be possible to predict similar internal wave attractors in ocean basins or lakes using ray tracing. This finding could be relevant to an experiment indicating inertial oscillations in a fluid contained in a truncated cone rotating around its axis.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
User Contributions:
Comment about this article or add new information about this topic:
Unweaving the whirls
Article Abstract:
Issues concerning the scientific phenomenon of turbulence are discussed. Particular attention is given to descriptions of air turbulence and to degrees of predictability of air turbulence, as well as to the related concept of viscosity.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2001
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Spatially structured populations and harvest theory. Male harvest in relation to female removals in a black-taile deer population
- Abstracts: Late formation and prolonged differentiation of the Moon inferred from W isotopes in lunar metals. Evidence for a late chondritic veneer in the Earth's mantle from high-pressure partitioning of palladium and platinum
- Abstracts: Estimating the viability of a reintroduced New Zealand robin population as a function of predator control. An experiment testing whether condition survival is limited by food supply in a reintroduced Hihi population
- Abstracts: A vertebrate model of extreme physiological regulation. China's environment in a globalizing world. Tree trail to Chaco Canyon
- Abstracts: Interaction between a transcriptional activator and transcription factor IIB in vivo. Splicing-related catalysis by protein-free snRNAs