Results 201 to 210 of about 67,930 (246)

On the Influence of the Molecular Prandtl Number on the Turbulent Prandtl Number

1979
Much more work has been done on the problem of turbulent transfer of momentum in a shear flow than on the problem of turbulent heat transfer. One of the reasons is obviously the fact, that from an experimental point of view informations about velocity-velocity correlations are easier to obtain compared with temperature-velocity correlations.
M. Jischa, H. B. Rieke
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Thermosolutal convection at infinite Prandtl number: initial layer and infinite Prandtl number limit

Applicable Analysis, 2013
We examine the initial layer problem and the infinite Prandtl number limit of the thermosolutal convection, which is applicable to magma chambers. We derive the effective approximating system of the Boussinesq system at large Prandtl number using two time scale approach [M.
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The turbulent Prandtl number in the near-wall region for low-Prandtl-number gas mixtures

International Journal of Heat and Mass Transfer, 1996
Results of experiments for binary gas mixtures, with molecular Prandtl numbers in the range 0.18–0.7 in flow in a smooth circular tube with constant transport properties were employed to examine models hypothesized for the distribution of the turbulent Prandtl number, Prt,{{y+, Pr, Re}}.
D.M. McEligot, M.F. Taylor
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Prandtl-Zahl Pr (Prandtl number Pr)

2000
Es handelt sich um eine dimensionslose Kombination von Stoffwerten, die damit einerseits wiederum ein Stoffwert ist, andererseits aber audi als Kennzahl im Sinne der Dimensionsanalysis angesehen werden kann.
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Free convection at low Prandtl numbers

Journal of Fluid Mechanics, 1969
In this paper it is shown that the free convection boundary layer approaches a singular character if the Prandtl number tends to zero. The method of matched asymptotic expansions is used to integrate the equations for this extreme case. An expression is derived for the Nusselt—Grashof relation and the results are compared with those of previous ...
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Prandtl number effects in convective turbulence

Journal of Fluid Mechanics, 1999
The effect of Prandtl number on the dynamics of a convective turbulent flow is studied by numerical experiments. In particular, three series of experiments have been performed; in two of them the Rayleigh number spanned about two decades while the Prandtl number was set equal to 0.022 (mercury) and 0.7 (air).
Verzicco, R., Camussi, R.
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Turbulente Prandtl-Zahl Prt (turbulent Prandtl number Prt)

2000
Es handelt sich urn eine Stromungsgrose (keine Stoffgrose), die in Analogie zur molekularen Prandtl-Zahl (einer Stoffgrose) eingefuhrt worden ist. Sie ist keine dimensionslose Kennzahl im Sinne der Dimensionsanalysis.
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Turbulent Prandtl number in circular pipes

International Journal of Heat and Mass Transfer, 1984
Presentation d'une methode de calcul du nombre de Prandtl pour un ecoulement turbulent dans une conduite circulaire a partir du nombre de Nusselt. Resultats obtenus pour differents fluides a differentes temperatures: eau, CO 2 , glycerol, ethylene ...
A. Malhotra, S.S. Kang
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Rotating convection at moderate Prandtl number

Physica A: Statistical Mechanics and its Applications, 1998
Abstract A small rotation is shown to inhibit the spiral chaos which develops in Rayleigh–Benard convection at moderate Prandtl number. Near the critical rotation for the onset of the Kuppers–Lortz instability, large coherent targets embedded in a turbulence background are formed in the case of free-slip top and bottom boundary conditions, while in ...
Y. Ponty, T. Passot, P.L. Sulem
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Convection at very low Prandtl numbers

Physics of Fluids A: Fluid Dynamics, 1990
The transition from thermal convection in the form of rolls in a fluid layer heated from below to traveling wave convection occurs at the Rayleigh number RII=1854 in the limit of low Prandtl numbers and in the presence of no-slip boundaries. While the traveling wave convection exhibits similar properties at moderately low and very low Prandtl numbers ...
Clever, R. M., Busse, F. H.
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