Experimental determination of three-dimensional dispersivities in homogeneous porous medium

ABSTRACTA closed-form solution for a macroscopically homogeneous, fully anisotropie layer subject to non-uniform through-thickness eigenstrain is presented, and employed in determining the three-dimensional deformation and stress states of a thermally loaded ceramic film with microstructure-induced macroscopic anisotropy. The resultant stress field is compared with those that could be deduced by experimental determination of the curvature and the classical structural theories.

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I mpact of compaction and thaw conditionson deformation characteristics of thawing soils

Moscow University Bulletin. Series 4. Geology ◽

10.33623/0579-9406-2017-1-58-63 ◽

2017 ◽

pp. 58-63

Author(s):

P. I. Kotov ◽

L. T. Roman ◽

M. N. Tsarapov

Keyword(s):

Physical Properties ◽

Experimental Determination ◽

Sandy Loam ◽

Three Dimensional ◽

Deformation Characteristics ◽

Clay Loam ◽

Laboratory Studies ◽

Compression Coefficient ◽

Plane Parallel

The results of laboratory studies of the effect of thawing conditions (plane-parallel or three dimensional) on the deformation characteristics (thawing and compression coefficients) thaw- ing soils (sand, sandy loam, clay loam) with desired physical properties of massive and layered cryogenic textures presented in the article. It was found that the values of the thawing coefficient bigger after three dimensional thawing, and compression coefficient after plane- parallel thaw- ing. The obtained data allowed to establish the applicability of the experimental determination of thawing soils deformation characteristics regardless of thawing conditions.

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Stresses in Pressurized Circular Shells With Discontinuities, With or Without Stiffeners

Journal of Ship Research ◽

10.5957/jsr.1972.16.2.140 ◽

1972 ◽

Vol 16 (02) ◽

pp. 140-147

Author(s):

A. J. Durelli ◽

V. J. Parks

Keyword(s):

Experimental Determination ◽

Mechanical Strain ◽

Three Dimensional ◽

Pressure Vessels ◽

Circular Cylinders ◽

Constant Thickness ◽

Strain Gages ◽

Circular Holes ◽

Reinforcing Ribs

This paper is a summary of a series of five research programs dealing with the experimental determination of stresses, strains, and displacements in circular cylinders subjected to pressure. The vessels have either constant thickness or transverse reinforcing ribs. Circular holes, with either plain or reinforced edges, are located in different positions of the vessels. The methods used for the analysis are: brittle coatings, three-dimensional photoelasticity ("freezing" technique), and electrical and mechanical strain gages. The most important results are summarized in a table. These results will be of interest to designers of underwater ships and of pressure vessels in general.

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Three-dimensional absolute and convective instabilities at the onset of convection in a porous medium with inclined temperature gradient and vertical throughflow

Journal of Fluid Mechanics ◽

10.1017/s0022112009992163 ◽

2009 ◽

Vol 641 ◽

pp. 475-487 ◽

Cited By ~ 26

Author(s):

LEONID BREVDO

Keyword(s):

Porous Medium ◽

Rayleigh Number ◽

Temperature Gradient ◽

Three Dimensional ◽

Onset Of Convection ◽

Convective Instabilities ◽

Homogeneous Porous Medium ◽

Vertical Throughflow ◽

Speed Of Propagation ◽

Inclined Temperature Gradient

By using the mathematical formalism of absolute and convective instabilities, we study in this work the nature of unstable three-dimensional localized disturbances at the onset of convection in a flow in a saturated homogeneous porous medium with inclined temperature gradient and vertical throughflow. It is shown that for marginally supercritical values of the vertical Rayleigh numberRvthe destabilization has the character of absolute instability in all the cases in which the horizontal Rayleigh numberRhis zero or the Péclet numberQvis zero. In all the cases in whichRhandQvare both different from zero, at the onset of convection the instability is convective. In the latter cases, the growing emerging disturbance has locally the structure of a non-oscillatory longitudinal roll, and its group velocity points in the direction opposite the direction of the applied horizontal temperature gradient, i.e. parallel to the axis of the roll. The speed of propagation of the unstable wavepacket increases withQvand generally increases withRh.

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