Thermal plumes and convection in highly compressible fluids.

نویسندگان

  • Y Chiwata
  • A Onuki
چکیده

We present simple hydrodynamic equations of supercritical fluids close to the gas-liquid critical point. We numerically solve them to examine plume generation and convection under gravity. These results are in good agreement with the experiment [A. B. Kogan and H. Meyer, Phys. Rev. E 63, 056310 (2001)]. This Letter is a first study of transient behavior of convection, which is unique in compressible fluids due to the piston effect.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Thermal signature of plumes in turbulent convection: The skewness of the derivative.

We present experimental evidence that, in the hard turbulence regime of Rayleigh-Bénard convection, the temperature fluctuations are produced by buoyancy, despite the presence of a mean horizontal flow at the plates. In a convection cell of aspect ratio 1, we measure the temperature time derivative for Ra from 2310 to 1310, which is skewed toward the negative in the region outside the cold ther...

متن کامل

Compressible thermochemical convection and application to lower mantle structures

[1] A new finite element code for compressible thermochemical convection is developed to study the stability of a chemical layer at the base of the mantle. Using composition-dependent compressibility and a density difference between compositions at a reference pressure, a composition-dependent density profile is derived. Together with depth-dependent thermal expansion, this combination of param...

متن کامل

Convection Heat Transfer Modeling of Nano- fluid Tio2 Using Different Viscosity Theories

In this paper, the effects of adding nanoparticles including Tio2 to a fluid media for purpose of free convection heat transfer improvement were analyzed. The free convection was assumed to be in laminar flow regime and the solutions and calculations were all done by the integral method. Water, as a Newtonian fluid, was considered the base fluid (water) and all the thermo physical properties of...

متن کامل

Plumes in stellar convection zones

All numerical simulations of compressible convection reveal the presence of strong downwards directed flows. Thanks to helioseismology, such plumes have now been detected also at the top of the solar convection zone, on supergranular scales. Their properties may be crudely described by adopting Taylor’s turbulent entrainment hypothesis, whose validity is well established under various condition...

متن کامل

Momentum and scalar transport within a vegetation canopy following atmospheric stability and seasonal canopy changes: the CHATS experiment

Momentum and scalar (heat and water vapor) transfer between a walnut canopy and the overlying atmosphere are investigated for two seasonal periods (before and after leaf-out), and for five thermal stability regimes (free and forced convection, near-neutral condition, transition to stable, and stable). Quadrant and octant analyses of momentum and scalar fluxes followed by space-time autocorrelat...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Physical review letters

دوره 87 14  شماره 

صفحات  -

تاریخ انتشار 2001