Mobilisation and stabilisation flow of multiple oil slugs in a capillary model

This paper introduces a method for simulating soil-structure coupling with water, which involves a series of visual effects, including wet granular materials, seepage flows, capillary action between grains, and dam breaking simulation. We develop a seepage flow based SPH-DEM framework to handle soil and water particles interactions through a momentum exchange term. In this framework, water is seen as a seepage flow through porous media by Darcy's law; the seepage rate and the soil permeability are manipulated according to drag coefficient and soil porosity. A water saturation-based capillary model is used to capture various soil behaviors such as sandy soil and clay soil. Furthermore, the capillary model can dynamically adjust liquid bridge forces induced by surface tension between soil particles. The adhesion model describes the attraction ability between soil surfaces and water particles to achieve various visual effects for soil and water. Lastly, this framework can capture the complicated dam-breaking scenarios caused by overtopping flow or internal seepage erosion that are challenging to simulate.

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A Fractal Model for Predicting the Relative Permeability of Rough-Walled Fractures

Advances in Civil Engineering ◽

10.1155/2021/6623275 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Zuyang Ye ◽

Wang Luo ◽

Shibing Huang ◽

Yuting Chen ◽

Aiping Cheng

Keyword(s):

Porous Media ◽

Multiphase Flow ◽

Relative Permeability ◽

Fractal Model ◽

Numerical Results ◽

Flow Paths ◽

Capillary Model ◽

Lognormal Distributions ◽

Fractal Characteristics ◽

Aperture Distribution

The relative permeability and saturation relationships through fractures are fundamental for modeling multiphase flow in underground geological fractured formations. In contrast to the traditional straight capillary model from porous media, the realistic flow paths in rough-walled fractures are tortuous. In this study, a fractal relationship between relative permeability and saturation of rough-walled fractures is proposed associated with the fractal characteristics of tortuous parallel capillary plates, which can be generalized to several existing models. Based on the consideration that the aperture distribution of rough-walled fracture can be represented by Gaussian and lognormal distributions, aperture-based expressions between relative permeability and saturation are explicitly derived. The developed relationships are validated by the experimental observations on Gaussian distributed fractures and numerical results on lognormal distributed fractures, respectively.

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Operability windows in viscoelastic slot coating flows using a simplified viscoelastic-capillary model

Rheologica Acta ◽

10.1007/s00397-017-1026-z ◽

2017 ◽

Vol 56 (9) ◽

pp. 707-717 ◽

Cited By ~ 5

Author(s):

Yong Woo Lee ◽

Won-Gi Ahn ◽

Jaewook Nam ◽

Hyun Wook Jung ◽

Jae Chun Hyun

Keyword(s):

Capillary Model ◽

Coating Flows ◽

Slot Coating

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Red cell distortion and conceptual basis of diffusing capacity estimates: finite element analysis

Journal of Applied Physiology ◽

10.1152/jappl.1997.83.4.1397 ◽

1997 ◽

Vol 83 (4) ◽

pp. 1397-1404 ◽

Cited By ~ 21

Author(s):

C. C. W. Hsia ◽

C. J. C. Chuong ◽

R. L. Johnson

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Variable Number ◽

Biased Sampling ◽

Conceptual Basis ◽

Diffusing Capacity ◽

Shape Distortion ◽

Element Analysis ◽

Capillary Model ◽

Capacity Estimates

Hsia, C. C. W., C. J. C. Chuong, and R. L. Johnson, Jr.Red cell distortion and conceptual basis of diffusing capacity estimates: finite element analysis. J. Appl. Physiol. 83(4): 1397–1404, 1997.—To understand the effects of dynamic shape distortion of red blood cells (RBCs) as it develops under high-flow conditions on the standard physiological and morphometric methods of estimating pulmonary diffusing capacity, we computed the uptake of CO across a two-dimensional geometric capillary model containing a variable number of equally spaced RBCs. RBCs are circular or parachute shaped, with the same perimeter length. Total CO diffusing capacity (Dl CO) and membrane diffusing capacity (Dm CO) were calculated by a finite element method. Dl COcalculated at two levels of alveolar[Formula: see text] were used to estimate Dm CO by the Roughton-Forster (RF) technique. The same capillary model was subjected to morphometric analysis by the random linear intercept method to obtain morphometric estimates of Dm CO. Results show that shape distortion of RBCs significantly reduces capillary diffusive gas uptake. Shape distortion exaggerates the conceptual errors inherent in the RF technique ( J. Appl. Physiol.79: 1039–1047, 1995); errors are exaggerated at a high capillary hematocrit. Shape distortion also introduces additional error in morphometric estimates of Dm CO caused by a biased sampling distribution of random linear intercepts; errors are exaggerated at a low capillary hematocrit.

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