Method for solving the problem of nonlinear heating a cylindrical body with unknown initial temperature

The model of body–vortex interactions, where the fluid flow is planar, ideal and unbounded, and the vortex is a point vortex, is studied. The body may have a constant circulation around it. The governing equations for the general case of a freely moving body of arbitrary shape and mass density and an arbitrary number of point vortices are presented. The case of a body and a single vortex is then investigated numerically in detail. In this paper, the body is a homogeneous, elliptical cylinder. For large body–vortex separations, the system behaves much like a vortex pair regardless of body shape. The case of a circle is integrable. As the body is made slightly elliptic, a chaotic region grows from an unstable relative equilibrium of the circle-vortex case. The case of a cylindrical body of any shape moving in fluid otherwise at rest is also integrable. A second transition to chaos arises from the limit between rocking and tumbling motion of the body known in this case. In both instances, the chaos may be detected both in the body motion and in the vortex motion. The effect of increasing body mass at a fixed body shape is to damp the chaos.

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Global well-posedness of the full compressible Hall-MHD equations

Advances in Nonlinear Analysis ◽

10.1515/anona-2020-0178 ◽

2021 ◽

Vol 10 (1) ◽

pp. 1235-1254

Author(s):

Qiang Tao ◽

Canze Zhu

Keyword(s):

Global Solution ◽

Large Time ◽

Initial Temperature ◽

Large Time Behavior ◽

Initial Energy ◽

Mhd Equations ◽

Well Posedness ◽

Time Behavior ◽

Magnetohydrodynamic Flows ◽

Hall Mhd

Abstract This paper deals with a Cauchy problem of the full compressible Hall-magnetohydrodynamic flows. We establish the existence and uniqueness of global solution, provided that the initial energy is suitably small but the initial temperature allows large oscillations. In addition, the large time behavior of the global solution is obtained.

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Effects of initial temperature on ignition and flame propagation of dual-fuel mixture in mixing layer

Combustion and Flame ◽

10.1016/j.combustflame.2020.11.027 ◽

2021 ◽

Vol 225 ◽

pp. 468-484

Author(s):

Xiaojun Zhang ◽

Chengwei Yuan ◽

Lei Zhou ◽

Wanhui Zhao ◽

Zongkuan Liu ◽

...

Keyword(s):

Flame Propagation ◽

Initial Temperature ◽

Mixing Layer ◽

Fuel Mixture ◽

Dual Fuel

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Strangeness Suppression and Color Deconfinement

EPJ Web of Conferences ◽

10.1051/epjconf/201817102005 ◽

2018 ◽

Vol 171 ◽

pp. 02005

Author(s):

Helmut Satz

Keyword(s):

Initial Temperature ◽

Strange Particle ◽

High Energy ◽

Universal Function ◽

Ideal Gas ◽

Entropy Density ◽

Suppression Factor ◽

Thermal Medium ◽

High Energy Collisions ◽

Hadronic Resonances

The relative multiplicities for hadron production in different high energy collisions are in general well described by an ideal gas of all hadronic resonances, except that under certain conditions, strange particle rates are systematically reduced. We show that the suppression factor γs, accounting for reduced strange particle rates in pp, pA and AA collisions at different collision energies, becomes a universal function when expressed in terms of the initial entropy density s0 or the initial temperature T of the produced thermal medium. It is found that γs increases from about 0.5 to 1.0 in a narrow temperature range around the quark-hadron transition temperature Tc ≃ 160 MeV. Strangeness suppression thus disappears with the onset of color deconfinement; subsequently, full equilibrium resonance gas behavior is attained.

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Phase changes and convection in the Earth’s mantle

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1965.0040 ◽

1965 ◽

Vol 258 (1088) ◽

pp. 276-283 ◽

Cited By ~ 76

Keyword(s):

Temperature Gradient ◽

Phase Change ◽

Initial Temperature ◽

Phase Changes ◽

Homogeneous Layer ◽

Transformation Zone ◽

Earth’S Mantle ◽

Transition Level ◽

Transformation Rates

A phase change may hinder or enhance convection, depending on its characteristics. Univariant transformations such as may occur in the mantle constitute a barrier to convection unless the motion starts at some distance above or below the transition level; an initial temperature gradient in excess of the adiabatic value is also required. Multivariant transformations only require, in the transformation zone, an initial gradient slightly greater than the adiabatic value for a homogeneous layer. The effect on convection of transformation rates is not likely to be serious.

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SAMPLE INJECTION IN PROGRAMMED TEMPERATURE GAS CHROMATOGRAPHY AND ITS SIGNIFICANCE FOR TRACE ANALYSIS

Canadian Journal of Chemistry ◽

10.1139/v65-207 ◽

1965 ◽

Vol 43 (5) ◽

pp. 1560-1568 ◽

Cited By ~ 9

Author(s):

L. W. Hollingshead ◽

H. W. Habgood ◽

W. E. Harris

Keyword(s):

Trace Analysis ◽

Initial Temperature ◽

Retention Volume ◽

Total Sample ◽

Sample Volume ◽

Plate Height ◽

Peak Broadening ◽

Increased Sensitivity ◽

Experimental Values ◽

Total Sample Volume

The measurement of apparent plate heights resulting from various values of the total sample volume has been carried out for C5 to C8n-alkanes on Apiezon L under both isothermal and p.t.g.c. conditions. Plug injection of samples was achieved through the use of a syringe plunger driven at constant speed by a motor. The time for injection of gas samples ranged from 1 to 300 s. All of the results, both isothermal and p.t.g.c, could be correlated to the same plot of Happ/Hc against √nΔVs/VT0 where Happ is the observed plate height, Hc the limiting plate height at low sample volumes, n the true plate number, ΔVs the sample volume, and VT0 the isothermal retention volume at the initial temperature. The experimental values lie somewhat above the theoretical curve calculated by van Deemter et al. It is confirmed that sample volumes less than [Formula: see text] give negligible excess peak broadening. Applying these concepts to trace analysis, very large samples may be used in p.t.g.c. under such initial temperature conditions that the major component is only weakly retained, while traces of heavier components are concentrated into narrow bands and eluted as sharp peaks with the increased sensitivity provided by the large sample. As an example, chromatograms are presented for the p.t.g.c. analysis of natural gas on deactivated alumina, using sample volumes ranging from 2 to 500 ml.

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