A new three-dimensional heat flux–temperature integral relationship for half-space transient diffusion

Three-dimensional wave propagation in an elastic half space is considered. The half space is traction free on half its boundary, while the remaining part of the boundary is free of shear traction and is constrained against normal displacement by a smooth, rigid barrier. A time-harmonic surface wave, traveling on the traction free part of the surface, is obliquely incident on the edge of the barrier. The amplitude and the phase of the resulting reflected surface wave are determined by means of Laplace transform methods and the Wiener-Hopf technique. Wave propagation in an elastic half space in contact with two rigid, smooth barriers is then considered. The barriers are arranged so that a strip on the surface of uniform width is traction free, which forms a wave guide for surface waves. Results of the surface wave reflection problem are then used to geometrically construct dispersion relations for the propagation of unattenuated guided surface waves in the guiding structure. The rate of decay of body wave disturbances, localized near the edges of the guide, is discussed.

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A New Facility for Measurements of Three-Dimensional, Local Subcooled Flow Boiling Heat Flux and Related Critical Heat Flux for PFCs

Fusion Science & Technology ◽

10.13182/fst41-1-12 ◽

2002 ◽

Vol 41 (1) ◽

pp. 1-12 ◽

Cited By ~ 6

Author(s):

Ronald D. Boyd ◽

Penrose Cofie ◽

Qing-Yuan Li ◽

Ali A. Ekhlassi

Keyword(s):

Heat Flux ◽

Critical Heat Flux ◽

Flow Boiling ◽

Three Dimensional ◽

Subcooled Flow Boiling ◽

Subcooled Flow ◽

New Facility

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Boundary-value problems in the kinetic theory of gases. Part 2. Thermal creep

Journal of Fluid Mechanics ◽

10.1017/s0022112071000314 ◽

1971 ◽

Vol 45 (4) ◽

pp. 759-768 ◽

Cited By ~ 13

Author(s):

M. M. R. Williams

Keyword(s):

Thermal Conductivity ◽

Heat Flux ◽

Temperature Gradient ◽

Kinetic Theory ◽

Effective Thermal Conductivity ◽

Half Space ◽

Thermal Creep ◽

Kinetic Theory Of Gases ◽

Boundary Wall ◽

Creep Velocity

The effect of a temperature gradient in a gas inclined at an angle to a boundary wall has been investigated. For an infinite half-space of gas it is found that, in addition to the conventional temperature slip problem, the component of the temperature gradient parallel to the wall induces a net mass flow known as thermal creep. We show that the temperature slip and thermal creep effects can be decoupled and treated quite separately.Expressions are obtained for the creep velocity and heat flux, both far from and at the boundary; it is noted that thermal creep tends to reduce the effective thermal conductivity of the medium.

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The Lid-Driven Cavity Flow: A Synthesis of Qualitative and Quantitative Observations

Journal of Fluids Engineering ◽

10.1115/1.3243136 ◽

1984 ◽

Vol 106 (4) ◽

pp. 390-398 ◽

Cited By ~ 229

Author(s):

J. R. Koseff ◽

R. L. Street

Keyword(s):

Heat Flux ◽

Flow Visualization ◽

Three Dimensional ◽

Symmetry Plane ◽

Lower Boundary ◽

Thymol Blue ◽

Width Ratio ◽

Cavity Depth ◽

Driven Cavity ◽

Turbulent Characteristics

A synthesis of observations of flow in a three-dimensional lid-driven cavity is presented through the use of flow visualization pictures and velocity and heat flux measurements. The ratio of the cavity depth to width used was 1:1 and the span to width ratio was 3:1. Flow visualization was accomplished using the thymol blue technique and by rheoscopic liquid illuminated by laser-light sheets. Velocity measurements were made using a two-component laser-Doppler-anemometer and the heat flux on the lower boundary of the cavity was measured using flush mounted sensors. The flow is three-dimensional and is weaker at the symmetry plane than that predicted by accurate two-dimensional numerical simulations. Local three-dimensional features, such as corner vortices in the end-wall regions and longitudinal Taylor-Go¨rtler-like vortices, are significant influences on the flow. The flow is unsteady in the region of the downstream secondary eddy at higher Reynolds numbers (Re) and exhibits turbulent characteristics in this region at Re = 10,000.

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