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Experimental evidence for seismically initiated gas bubble nucleation and growth in groundwater as a mechanism for co-seismic borehole water level rise and remotely triggered seismicity , Journal of Geophysical Research Solid Earth , , doi: Transient pore pressure response to confining stress excursions in Berea sandstone flooded with an aqueous solution of CO2 , Water Resources Research , 50, , doi: Hodges, R.
Modeling of flow and transport induced by production of hydrofracture stimulated gas wells near the Rulison nuclear test , Transport in Porous Media , doi: Maples, S. Tritium plume dynamics in the shallow unsaturated zone in an arid environment , Vadose Zone Journal , 12, doi: Stonestrom, D. Howe, S.
Jasoni, R. Shope, C. Influence of a large fluvial island, streambed, and streambank on surface water-groundwater fluxes and water table dynamics , Water Resources Research , doi: Injection of nuclear rocket exhaust and water into a deep unsaturated zone , Nuclear Technology , , Garcia, C. Interacting vegetative and thermal contributions to water movement in desert soil , Vadose Zone Journal , 10, Voepel, H. Garcia, A.
Dr. Clay A. Cooper
Transport of tritium contamination to the atmosphere in an arid environment , Vadose Zone Journal , 8, , doi: Ye, M. Decker, D. Preliminary numerical modeling and sub-scale experimental design of a nuclear rocket test facility with vadose zone exhaust sequestration at the Nevada Test Site. Breitmeyer, R. In addition, the fraction of the liquid and vapor phases in the flow varies very much, which affects the observed flow regimes in the heat exchanger channels. At the moment there are not so many experimental data and analytical correlations that would allow to estimate the heat transfer coefficient during the flow of a two-phase mixture flow at low temperatures.
The work is devoted to the study of the boiling process of multicomponent working fluids used in refrigeration and cryogenic engineering. The description of the method of determination of heat transfer coefficient during boiling of mixtures in horizontal heated channel is given as well as the design of the experimental stand allowing to make such measurements. This stand is designed on the basis of a refrigeration unit operating on the Joule-Thomson throttle cycle and makes it possible to measure the heat transfer coefficient with a good accuracy.
Also, the calculated values of the heat transfer coefficient, obtained with the use of various correlations, are compared with the existing experimental data. Knowing of the heat transfer coefficient will be very useful in the design of heat exchangers for low-temperature units operating on a mixture refrigerant.
Ebook Transient Phenomena In Multiphase And Multicomponent Systems Research Report 2000
Device and method for measuring multi-phase fluid flow in a conduit having an abrupt gradual bend. A system is described for measuring fluid flow in a conduit having an abrupt bend. The system includes pressure transducers, one disposed in the conduit at the inside of the bend and one or more disposed in the conduit at the outside of the bend but spaced a distance therefrom. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit.
For multi-phase fluid , the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow. A system for measuring fluid flow in a conduit having an abrupt bend.
The pore-scale dynamics that govern multiphase flow under variable stress conditions are not well understood. This lack of fundamental understanding limits our ability to quantitatively predict multiphase flow and fluid distributions in natural geologic systems. In this research, we focus on pore-scale, single and multiphase flow properties that impact displacement mechanisms and residual trapping of non-wetting phase under varying stress conditions.
X-ray micro-tomography is used to image pore structures and distribution of wetting and non-wetting fluids in water-wet synthetic granular packs, under dynamic load. Micro-tomography images are also used to determine structural features such as medial axis, surface area, and pore body and throat distribution; while the corresponding transport properties are determined from Lattice-Boltzmann simulations performed on lattice replicas of the imaged specimens. Results are used to investigate how inter-granular deformation mechanisms affect fluid displacement and residual trapping at the pore-scale.
This will improve our understanding of the dynamic interaction of mechanical deformation and fluid flow during enhanced oil recovery and geologic CO2 sequestration. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U. Long residence times of rapidly decomposable soil organic matter: application of a multi-phase , multi-component , and vertically resolved model BAMS1 to soil carbon dynamics.
Accurate representation of soil organic matter SOM dynamics in Earth system models is critical for future climate prediction, yet large uncertainties exist regarding how, and to what extent, the suite of proposed relevant mechanisms should be included. To investigate how various mechanisms interact to influence SOM storage and dynamics, we developed an SOM reaction network integrated in a one-dimensional, multi-phase , and multi-component reactive transport solver.
The model includes representations of bacterial and fungal activity, multiple archetypal polymeric and monomeric carbon substrate groups, aqueous chemistry, aqueous advection and diffusion, gaseous diffusion, and adsorption and protection and desorption from the soil mineral phase. The model predictions reasonably matched observed depth-resolved SOM and dissolved organic matter DOM stocks and fluxes, lignin content, and fungi to aerobic bacteria ratios.
We performed a suite of sensitivity analyses under equilibrium and dynamic conditions to examine the role of dynamic sorption, microbial assimilation rates, and carbon inputs. To our knowledge, observations do not exist to fully test such a complicated model structure or to test the hypotheses used to explain observations of substantial storage of very old SOM below the rooting depth.
Nevertheless, we demonstrated that a reasonable combination of sorption parameters, microbial biomass and necromass dynamics, and advective transport can match observations without resorting to an arbitrary depth-dependent decline in SOM turnover rates, as is often done. Multi-component fluid flow through porous media by interacting lattice gas computer simulation. In this work we study structural and transport properties such as power-law behavior of trajectory of each constituent and their center of mass, density profile, mass flux, permeability, velocity profile, phase separation, segregation, and mixing of miscible and immiscible multicomponent fluid flow through rigid and non-consolidated porous media.
The considered parameters are the mass ratio of the components, temperature, external pressure, and porosity. Due to its solid theoretical foundation and computational simplicity, the selected approaches are the Interacting Lattice Gas with Monte Carlo Method Metropolis Algorithm and direct sampling, combined with particular collision rules. The percolation mechanism is used for modeling initial random porous media.
The introduced collision rules allow to model non-consolidated porous media, because part of the kinetic energy of the fluid particles is transfered to barrier particles, which are the components of the porous medium. Having gained kinetic energy, the barrier particles can move. A number of interesting results are observed.
This study involves developing computer simulation models with efficient serial and parallel codes, extensive data analysis via graphical utilities, and computer visualization techniques. Device and method for measuring multi-phase fluid flow and density of fluid in a conduit having a gradual bend. A system is described for measuring fluid flow in a conduit having a gradual bend or arc, and a straight section. The system includes pressure transducers, one or more disposed in the conduit on the outside of the arc, and one disposed in the conduit in a straight section thereof.
A system for measuring fluid flow in a conduit having a gradual bend or arc, and a straight section. Multiphase , multicomponent flow and transport models for Nuclear Test-Ban Treaty monitoring and nuclear waste disposal applications. The formation of a three-phase heat pipe with counter-circulation of vapor and brine occurs as water vapor is driven away from the heat source, condenses, and flows back towards the heat source, leading to changes in porosity, permeability, temperature, saturation, and thermal conductivity of the backfill salt surrounding the waste canisters.
Heat pipe formation depends on temperature, moisture availability and fluid mobility. In certain cases, dehydration of hydrous minerals provided sufficient additional moisture to push the system into a sustained heat pipe where simulations neglecting this process did not. The experiment was designed to study transport processes in the system that have not been satisfactorily quantified in prior work.
Initial results from the experimental effort offer promising insights. Abstract shortened by UMI. Reservoir simulators are widely used to constrain uncertainty in the petrophysical properties of subsurface formations by matching the history of injection and production data.
However, such measurements may be insufficient to uniquely characterize a reservoir's properties. Monitoring of natural isotopic and introduced tracers is a developing technology to further interrogate the subsurface for applications such as enhanced oil recovery from conventional and unconventional resources, and CO2 sequestration. Two campaigns of multiple perfluorocarbon tracers were injected together with CO2 and monitored at two wells at 68 m and m from the injection site. The tracer data suggest that multiple CO2 flow paths developed towards the monitoring wells, indicative of either channeling through high permeability pathways or of fingering.
The results demonstrate that tracers provide an important complement to transient pressure data. Numerical modeling is essential to further explain and interpret the observations. To aid the development of tracer technology, we enhanced a compositional multiphase reservoir simulator to account for tracer transport.
Our research simulator uses higher-order finite element FE methods that can capture the small-scale onset of fingering on the coarse grids required for field-scale modeling, and allows for unstructured grids and anisotropic heterogeneous permeability fields. Mass transfer between fluid phases and phase behavior are modeled with rigorous equation-of-state based phase-split calculations.
We present our tracer simulator and preliminary results related to the Cranfield experiments. Applications to noble gas tracers in unconventional resources are presented by Darrah et al. A two dimensional finite-element model was developed to predict coupled transient flow and multicomponent transport of organic chemicals which can partition between NAPL, water, gas and solid phases in porous media under the assumption of local chemical equilibrium.
A two-dimensional finite-element model was developed to predict coupled transient flow and multicomponent transport of organic chemicals which can partition between nonaqueous phase liquid, water, gas and solid phases in porous media under the assumption of local chemical equilib High-resolution simulations of multi-phase flow in magmatic-hydrothermal systems with realistic fluid properties. Realistic modelling of multi-phase fluid flow, energy and component transport in magmatic-hydrothermal systems is very challenging because hydrological properties of fluids and rocks vary over many orders of magnitude and the geometric complexities of such systems.
Furthermore, density dependent component transport and transient permeability variations due to P-T changes and fluid -rock interactions introduce additional difficulties. As a result, the governing equations for the hydrodynamics, energy and component transport, and thermodynamics in magmatic hydrothermal systems are highly non-linear and strongly coupled. We are combining higher order finite-element FE methods with total variation diminishing finite volume TVDFV methods to model the hydrodynamics and energy and component transport of magmatic hydrothermal systems.
Furthermore, efficient matrix solvers can be employed to model fluid flow in geologically realistic structures .
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The governing equations are linearized by operator-splitting and solved sequentially using a Picard iteration scheme. We chose the system water-NaCl as a realistic proxy for natural fluids occurring in magmatic-hydrothermal systems. An in-depth evaluation of the available experimental and theoretical data led to a consistent and accurate set of formulations for the PVTXH relations that are valid from 0 to C, 0 to MPa, and 0 to 1 XNa.
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- 20th Century Jewish Religious Thought.
- Projects – Fluids and Surfaces Group.
- Terrorism: The Self-Fulfilling Prophecy.
Recent advances in quantitative analysis of fluid interfaces in multiphase fluid flow measured by synchrotron-based x-ray microtomography. Imaging of fluid interfaces in three-dimensional porous media via x-ray microtomography is an efficient means to test thermodynamically derived predictions on the relationship between capillary pressure, fluid saturation and specific interfacial area Pc-Sw-Anw in partially saturated porous media. Various experimental studies exist to date that validate the uniqueness of the Pc-Sw-Anw relationship under static conditions and with current technological progress direct imaging of moving interfaces under dynamic conditions is also becoming available.
Image acquisition and subsequent image processing currently involves many steps each prone to operator bias, like merging different scans of the same sample obtained at different beam energies into a single image or the generation of isosurfaces from the segmented multiphase image on which the interface properties are usually calculated. We demonstrate that with recent advancements in i image enhancement methods, ii multiphase segmentation methods and iii methods of structural analysis we can considerably decrease the time and cost of image acquisition and the uncertainty associated with the measurement of interfacial properties.
In particular, we highlight three notorious problems in multiphase image processing and provide efficient solutions for each: i Due to noise, partial volume effects, and imbalanced volume fractions, automated histogram-based threshold detection methods frequently fail. However, these impairments can be mitigated with modern denoising methods, special treatment of gray value edges and adaptive histogram equilization, such that most of the standard methods for threshold detection Otsu, fuzzy c-means, minimum error, maximum entropy coincide at the same set of values.
In a synthetic test image some local segmentation methods. Multicomponent membranes. A multicomponent membrane which may be used for separating various components which are present in a fluid feed mixture comprises a mixture of a plasticizer such as a glycol and an organic polymer cast upon a porous organic polymer support.