Results 151 to 160 of about 5,304 (193)

Modified turbulent Prandtl number model for helium–xenon gas mixture with low Prandtl number

Nuclear Engineering and Design, 2020
Abstract Gas-cooled space nuclear-reactor systems generally adopt the helium–xenon mixture (He–Xe) as a working fluid and coolant, the Prandtl number (Pr) of which is low for recommended mixing ratios. Many studies have shown that the turbulent Pr (Prt) is not constant and that it is greater than 0.85 for low-Pr fluids.
Biao Zhou, Yu Ji, Jun Sun, Yuliang Sun
openaire   +1 more source

Wall plume at extreme prandtl numbers

International Journal of Heat and Mass Transfer, 1987
An analysis of the wall plume for asymptotically large and small Pr has been carried out. It is shown that the nature of the transport differs significantly from the vertical surface and the line source plume. The asymptotically large Pr condition is studied. The other extreme of vanishingly small Pr is considered also.
openaire   +2 more sources

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 ...
openaire   +2 more sources

High Prandtl number convection

Physics of the Earth and Planetary Interiors, 1979
Abstract The theory of convection in a layer heated from below is reviewed with particular emphasis on the limit of infinite Prandtl number. The review is restricted to qualitative properties of the problems which do not depend on special conditions. Similarities and differences between convection in a plane layer and in a spherical shell are pointed
openaire   +1 more source

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.
openaire   +1 more source

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.
openaire   +1 more source

A Reinterpretation of the Turbulent Prandtl Number

Industrial & Engineering Chemistry Research, 2002
The eddy viscosity at any location in fully developed turbulent flow in a round pipe is shown by an exact analysis to be simply the ratio of the shear stress due to the time-averaged turbulent fluc...
openaire   +1 more source

Thermally driven flows at low Prandtl numbers: An extension of the Prandtl-Batchelor theorem

International Journal of Engineering Science, 1995
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Blythe, P. A., Liakopoulos, A., Haruta, E.   +2 more
openaire   +1 more source

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.
openaire   +1 more source

Turbulent Thermal Convection at Arbitrary Prandtl Number

The Physics of Fluids, 1962
The mixing-length theory of turbulent thermal convection in a gravitationally unstable fluid is extended to yield the dependence of Nusselt number H/H0 on both Prandtl number σ and Rayleigh number Ra. The analysis assumes a layer of Boussinesq fluid contained between infinite, horizontal, perfectly conducting, rigid plates.
openaire   +1 more source