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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 379 records · Page 21
All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

Deposition of high permeability FeCoN films on mica substrates

In this study, sheet mica was explored as an alternative substrate for thin film deposition due to its unique layered structure and atomically flat surface. Static magnetic properties and microwave permeability of sputtered FeCoN films on mica with and without SiO{sub 2} under-layer were examined. In-plane isotropy and a large coercivity of 70 Oe were observed for the film directly deposited on mica substrate. With the insertion of 40 nm SiO{sub 2} under-layer between the film and mica substrate, well-defined in-plane anisotropy is formed due to the significant reduce in film residual stress, associated with a 3 Oe coercive force along easy axis. As a result, excellent microwave properties have been achieved and are comparable with the same film on Si substrate. Moreover, the permeability spectra are surprisingly stable from room temperature up to 390 K. Mica is proved as a promising substrate for magnetic films with high microwave performance, which is a great advantage for practical applications. Furthermore, our results provide an effective way to reduce the residual stress in sputtered films.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2016

Optical investigation of effective permeability of dilute magnetic dielectrics with magnetic field

The prime objective of this paper is to investigate the magnetic nature of dilute magnetic dielectrics (DMD) under variation of external magnetic field. The said variation is studied over developed nano-sized Gadolinium Oxide as a DMD system. The observed experimental field variation of the effective magnetic permeability is analyzed results of optical experiment. The experiment records the variation of Brewster angle of incident polarized LASER beam from the surface of developed DMD specimen with applied out of plane external magnetic field. The effective refractive index and hence relative magnetic permeability were estimated following electro-magnetic theory. The overall results obtained and agreement between theory and experiment are good.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2014

Monitoring of permeability of different analytes in human normal and cancerous bladder tissues in vitro using optical coherence tomography

We report our preliminary results on quantification of glucose and dimethyl sulfoxide (DMSO) diffusion in normal and cancerous human bladder tissues in vitro by using a spectral domain optical coherence tomography (SD-OCT). The permeability coefficients (PCs) of a 30% aqueous solution of glucose are found to be (7.92 ± 0.81) × 10{sup -6} cm s{sup -1} and (1.19 ± 0.13) × 10{sup -5} cm s{sup -1} in normal and cancerous bladder tissues, respectively. The PCs of 50% DMSO are calculated to be (8.99 ± 0.93) × 10{sup -6} cm s{sup -1} and (1.43 ± 0.17) × 10{sup -5} cm s{sup -1} in normal and cancerous bladder tissues, respectively. The obtained results show a statistically significant difference in permeability of normal and cancerous tissue and indicate that the PC of 50% DMSO is about 1.13-and 1.21-fold higher than that of 30% glucose in normal bladder and cancerous bladder tissues, respectively. Thus, the quantitative measurements with the help of PCs from OCT images can be a potentially powerful method for bladder cancer detection. (optical coherence tomography)

60 APPLIED LIFE SCIENCES↗
DOE OSTI2023

Utah FORGE 5-2419: Seismicity-Permeability Relationships Probed via Nonlinear Acoustic Imaging - Workshop Presentation

This is a presentation on the Seismicity-Permeability Relationships Probed via Nonlinear Acoustic Imaging project by Pennsylvania State University, presented by Derek Elsworth. The project's objectives were to explore controls and acoustic signatures of aseismic through seismic evolution of friction-stability-permeability relationships on fractures in shear-reactivation, link this reactivation to key features of the pre-existing stress state, and upscale these indexes to reservoir scale to drive successful reservoir stimulation. This presentation was featured in the Utah FORGE R&D Annual Workshop on September 8, 2023. The workshop provided a valuable opportunity to explore the progress made in each of the 17 Research and Development projects funded under Solicitation 2020-1 which aim to enhance our understanding of the crucial factors influencing the development of Enhanced Geothermal Systems (EGS) reservoirs and resources.

15 GEOTHERMAL ENERGY↗
DOE OSTI2024

Utah FORGE 5-2428: Coupled Investigation of Fracture Permeability Impact on Reservoir Stress and Seismic Slip - 2024 Annual Workshop Presentation

This is a presentation on the Coupled Investigation of Fracture Permeability Impact on Reservoir Stress and Seismic Slip Behavior by Lawrence Livermore National Laboratory, presented by Kayla Kroll. This presentation addresses testing and modelling related to the dependency of EGS production on sustained permeability and sufficient fluid flow through pre-existing or induced fractures in hot rock. This presentation was featured in the Utah FORGE R&D Annual Workshop on August 13, 2024.

15 GEOTHERMAL ENERGY↗
DOE OSTI2026

Coupled Investigation of Fracture Permeability Impact on Reservoir Stress and Seismic Slip Behavior (Final Technical Report)

Enhanced Geothermal Systems (EGS) produce clean energy by circulating fluid through hot rock deep underground and bringing that heat to the surface to generate electricity. For this process to work reliably, fluids must be able to move efficiently through networks of natural or engineered fractures in the rock. Enhancing and maintaining subsurface permeability over time is essential for sustainable energy production. However, fluid injection changes the underground temperature, pressure, rock stress, and chemistry, which can alter permeability and sometimes trigger earthquakes. Predicting these interconnected processes remains a key challenge. To address this, we combined high-temperature laboratory experiments with high-fidelity simulations to better understand how fractures in geothermal reservoirs evolve over time. Our experiments measured how fractures respond to stress, slip, slip rate, and chemical reactions under geothermal conditions. These data were integrated into coupled thermal-hydrological-mechanical-chemical and earthquake (THMC+E) models tailored to the Utah FORGE site. The validated modeling framework improves predictions of reservoir performance and seismic response and helps guide operational decisions. This work reduces technical risk and strengthens the scientific foundation needed to make geothermal energy a reliable and scalable clean energy resource.

15 GEOTHERMAL ENERGY↗
DOE OSTI2015

Ultrathin gas permeable oxide membranes for chemical sensing: Nanoporous Ta 2 O 5 test study

Conductometric gas sensors made of gas permeable metal oxide ultrathin membranes can combine the functions of a selective filter, preconcentrator, and sensing element and thus can be particularly promising for the active sampling of diluted analytes. Here we report a case study of the electron transport and gas sensing properties of such a membrane made of nanoporous Ta 2 O 5 . These membranes demonstrated a noticeable chemical sensitivity toward ammonia, ethanol, and acetone at high temperatures above 400 °C. Furthermore, different from traditional thin films, such gas permeable, ultrathin gas sensing elements can be made suspended enabling advanced architectures of ultrasensitive analytical systems operating at high temperatures and in harsh environments.

36 MATERIALS SCIENCE↗
DOE OSTI2021

A microfluidic study of transient flow states in permeable media using fluorescent particle image velocimetry

Velocity fields in flow in permeable media are of great importance to many subsurface processes such as geologic storage of CO 2 , oil and gas extraction, and geothermal systems. Steady-state flow is characterized by velocity fields that do not change significantly over time. The flow field transitions to a new steady state once it experiences a disturbance such as a change in flow rate or in pressure gradient. This transition is often assumed to be instantaneous, which justifies the expression of constitutive relations as functions of instantaneous phase saturations. This work examines the evolution of velocity fields in a surrogate quasi-2D permeable medium using a microfluidic device, a microscopy system, and a high-speed camera. Tracer particles are injected into the medium along with DI water. The evolution of the velocity field is examined by tracing these particles in the captured images using the standard high-density particle image velocimetry algorithm founded on cross-correlation. The results suggest that the transition between steady states for an incompressible fluid takes a finite and non-negligible amount of time that is independent of the magnitude of the change in pressure gradient. The existence of transient states and the nature of the response during these states are readily interpreted by the principle of least action where flow gradually establishes an optimal configuration such that energy dissipation is 2 minimized. The findings provide evidence against the applicability of the assumption that flowing phases relax instantaneously to their steady states and, hence, against the accuracy of the classical multiphase extension of Darcy's law.

42 ENGINEERING↗
NASA NTRS2017

Modeling the Relationship Between Porosity and Permeability During Oxidation of Ablative Materials

The ablative materials used in thermal protection systems (TPS) undergo oxidation during atmospheric entry which leads to an in-depth change in both permeability and porosity. These properties have a significant affect on heat transfer in a TPS during entry. X-ray micro-tomography has provided 3D images capturing the micro-structure of TPS materials. In this study, we use micro-tomography based simulations to create high-fidelity models relating permeability to porosity during oxidation of FiberForm, the carbon fiber preform of the Phenolic Impregnated Carbon Ablator (PICA) often used as a TPS material. The goal of this study is to inform full-scale models and reduce uncertainty in TPS modeling.

Ablativ↗
DOE OSTI2014

An Injectable Apatite Permeable Reactive Barrier for In Situ 90Sr Immobilization

An injectable permeable reactive barrier (PRB) technology was developed to sequester 90Sr in groundwater through the in situ formation of calcium-phosphate mineral phases, specifically apatite that incorporates 90Sr into the chemical structure. An integrated, multi-scale development and testing approach was used that included laboratory bench-scale experiments, an initial pilot-scale field test, and the emplacement and evaluation of a 300-ft-long treatability-test-scale PRB. Standard groundwater wells were used for emplacement of the treatment zone, allowing treatment of contaminants too deep below ground surface for trench-and-fill type PRB technologies. The apatite amendment formulation uses two separate precursor solutions, one containing a Ca-citrate complex and the other a Na-phosphate solution, to form apatite precipitate in situ. Citrate is needed to keep calcium in solution long enough to achieve a more uniform and areally extensive distribution of precipitate formation. In the summer of 2008, the apatite PRB technology was applied as a 91-m (300-ft) -long permeable reactive barrier on the downgradient edge of a 90Sr plume beneath the Hanford Site in Washington State. The technology was deployed to reduce 90Sr flux discharging to the Columbia River. Performance assessment monitoring data collected to date indicate the barrier is meeting performance objectives. The average reduction in 90Sr concentrations at four downgradient compliance monitoring locations was 95% relative to the high end of the baseline range approximately 1 year after treatment, and continues to meet remedial objectives more than 4 years after treatment.

in situ 90Sr immobilization↗
DOE OSTI2019

MINERALOGICAL AND TEXTURAL CONTROLS ON SHEAR STRENGTH, SLIP STABILITY AND PERMEABILITY OF FAULTS

Induced seismicity resulting from fluid injection into the subsurface related to water and CO2 disposal, hydraulic fracturing and the stimulation of geothermal reservoirs present an important societal concern. These human activities involve the injection of large volumes of pressurized fluid into the subsurface, potentially at high rates, raising local pore pressures and disturbing the pristine local stress regime by lowering effective normal stress on pre-existing faults and fractures. The reduction of effective normal stress may trigger fault/fracture reactivation and in some cases result in hazardous seismic ruptures. Effective management and engineering of anthropogenic seismic events requires substantial understanding in the mechanisms, especially for the controlling factors on coupled rheological and transport response, including fault shear strength, slip stability, and permeability evolution during such events. In this study, we explore the coupled rheological and transport response of faults and fractures during reactivation as controlled by two fundamental controlling properties, viz., mineralogy and textural features. We approach this problem through shear experiments on analog faults and fractures via laboratory and numerical experiments. Specifically, we investigate: (1) the influence of frictionally weak minerals (talc) in mixtures of mineral analogs featuring contrasting frictional properties, (2) the influence of iron oxide grain coatings on quartz aggregates, and (3) the influence of fracture roughness in mated fractures on the ensemble shear strength, slip stability, and permeability evolution during reactivation events. We address the following questions in this study: (1) how much and what distribution of frictionally weak minerals is required to induce significant weakening in faults consisting of a matrix of frictionally strong minerals, (2) how does a pre-imposed weak mineral layer influence the rheological and transport behavior of faults, (3) what is the influence of a trace amount of grain coating materials introduce on the coupled behavior of faults, and finally (4) how do asperity height and wave length control the ensemble behavior of faults. These questions are explicitly answered in the following.

58 GEOSCIENCES↗
DOE OSTI2017

Calculation of Permeability for Granular Porous Media - 17030

The flow of a viscous fluid is considered to calculate the permeability of a porous medium with granular solid phase. Under the assumption of periodicity a unit cell which contains solid phase of granular shape is selected on the microscale and the flow field is calculated by solving Stokes problem in which inertial effects are ignored. A Boundary-Vale Problem is obtained by applying the theory of homogenization to slow viscous flow through porous structure on the microscale. It is shown that the permeability is dominantly determined by the flow direction along which the pressure gradient on the macro-scale is imposed. (authors)

36 MATERIALS SCIENCE↗
DOE OSTI2015

Influences of temperature on permeability changes of flow-paths altered by highly alkaline Ca-rich groundwater - 15192

Fractures (or cracks) in host rock around the geological repository are considered as main flow-paths for the migration of radionuclides. Such fractures would be altered by the alkaline components (Ca, Na, K) leaching from cementitious materials for the construction of the repository. While silicate minerals in fractures are dissolved by highly alkaline groundwater, secondary minerals would deposit on the surface of fractures because of the reaction between the alkaline components and silicate species. The authors' previous study showed the generation of CSH-gel and the clogging of micro flow-path under the condition of Ca-rich and high pH by flow experiments. The present study examined the permeability changes with temperature in micro flow-path flowing highly alkaline Ca-rich solution, considering temperature at the depth of geological disposal system. For the simulation of micro flow-path such as fractures, 'micro flow-cell', which nipped a thin Teflon sheet with a slit between granite chip and Teflon basement, were used for the experiments. Highly alkaline Ca-rich solution (pH>12 and 8.5 mM Ca(OH){sub 2}) were injected into micro flow-cell with 2.0 ml/h of flow rate under the given temperature conditions (278 K, 296 K or 313 K). As a result, the permeability became lower with the increase in temperature. In addition, the deposition rates of CSH-gel became larger with the increase in temperature, and the activation energy was estimated to be 32.0 kJ/mol. These results suggest that flow-paths around the geological repository would undergo the clogging with CSH-gel in a shorter time-period under a condition of higher temperature. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Calculation of Permeability for Porous Media with Platy Grains - 18095

The permeability is calculated numerically for a porous medium with granules of platy shape when pressure gradient is imposed externally across the medium by considering slow flow of a viscous fluid in the pores. Under the assumption of periodicity a unit cell which contains solid phase of platy granules is selected on the microscale and the flow field is calculated by solving Stokes problem in which inertial effects are ignored. A Boundary-Vale Problem is obtained in the course of applying the theory of homogenization to fluid flow through porous media. It is shown that the permeability is strongly influenced by the flow direction along which the pressure gradient on the macro-scale is imposed and the particle arrangement pattern in the unit cell used in the numerical computation. (authors)

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2017

Improved characterization of heterogeneous permeability in saline aquifers from transient pressure data during freshwater injection

Managing recharge of freshwater into saline aquifers requires accurate estimation of the heterogeneous permeability field for maximizing injection and recovery efficiency. Here we present a methodology for subsurface characterization in saline aquifers that takes advantage of the density difference between the injected freshwater and the ambient saline groundwater. We combine high-resolution forward modeling of density-driven flow with an efficient Bayesian geostatistical inversion algorithm. In the presence of a density difference between the injected and ambient fluids due to differences in salinity, the pressure field is coupled to the spatial distribution of salinity. This coupling renders the pressure field transient: the time evolution of the salinity distribution controls the density distribution which then leads to a time-evolving pressure distribution. We exploit this coupling between pressure and salinity to obtain an improved characterization of the permeability field without multiple pumping tests or additional salinity measurements. We show that the inversion performance improves with an increase in the mixed convection ratio—the relative importance between viscous forces from injection and buoyancy forces from density difference. Thus, our work shows that measuring transient pressure data at multiple sampling points during freshwater injection into saline aquifers can be an effective strategy for aquifer characterization, key to the successful management of aquifer recharge.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

Pore-Scale Determination of Gas Relative Permeability in Hydrate-Bearing Sediments Using X-Ray Computed Micro-Tomography and Lattice Boltzmann Method

This work uses X-ray computed micro-tomography (μCT) to monitor xenon hydrate growth in asandpack under the excess gas condition. The μCT images give pore-scale hydrate distribution and porehabit in space and time. We use the lattice Boltzmann method to calculate gas relative permeability (k rg ) as a function of hydrate saturation (S hyd ) in the pore structure of the experimental hydrate-bearingsand retrieved from μCT data. The results suggest the krg-Shyd data fit well a new model krg=(1-S hyd )•exp(–4.95•S hyd ) rather than the simple Corey model. In addition, we calculate k rg -S hyd curves using digitalmodels of hydrate-bearing sand based on idealized grain-attaching, coarse pore-filling, and dispersed pore-filling hydrate habits. Our pore-scale measurements and modeling show that the k rg -S hyd curves are similar regardless of whether hydrate crystals develop grain-attaching or coarse pore-filling habits. The dispersed pore filling habit exhibits much lower gas relative permeability than the other two, but it is not observed in the experiment and not compatible with Ostwald ripening mechanisms. We find that a single grain-shape factor can be used in the Carman-Kozeny equation to calculate k rg -S hyd data with known porosity and average grain diameter, suggesting it is a useful model for hydrate-bearing sand.

58 GEOSCIENCES↗
DOE OSTI2018

Inhibition of liver mitochondrial membrane permeability transition pore opening by quercetin and vitamin E in streptozotocin-induced diabetic rats

Highlights: • Quercetin and vitamin E after streptozotocin induction prevent hepatic tissues from oxidative stress. • Administration of quercetin and vitamin E significantly reduced the elevated levels of glucose, tissue peroxidation, and enzyme activity. • Quercetin and vitamin E reversed the opening of membrane permeability transition pore caused by induction of diabetes. • The result suggests that quercetin was more effective than vitamin E. Diabetes mellitus is a chronic metabolic disorder characterized by rise in blood glucose levels and generation of free radicals which could induce mitochondrial membrane permeability transition (MMPT) pore opening. This study examined the in vivo action of quercetin and vitamin E on MMPT in the liver of streptozotocin-induced diabetic rats orally pre-treated with 30 mg quercetin/kg body weight (STZQ), 10 mg vitamin E/kg body weight (STZVit.E) and 0.6 mg glibenclamide/kg body weight (STZG). Male albino wistar rats were used in the study and were injected intraperitonially with streptozotocin (STZ) (45 mg/kg body weight) in citrate buffer. The degrees of serum and tissue peroxidation, alanine and aspartate aminotransferase activity were investigated. MMPT pore was assessed as mitochondrial swelling and was monitored spectrophotometrically as changes in absorbance at 540 nm under succinate-energized condition. There was significant increase in serum glucose level, degree of tissue peroxidation, alanine and aspartate aminotransferase activity, cholesterol and triglycerides values in the diabetic control rats following streptozotocin induction. All the treatment had effect on the damage caused by streptozotocin. Quercetin exhibited the highest chemopreventive activity. Quercetin and vitamin E significantly reduced the blood glucose level, degree of tissue peroxidation and alanine and aspartate amino transferase activity. In vivo rat liver MMPT pore was opened in diabetic control rats and significantly inhibited in STZQ, STZV and STZG treated groups by 72.3%, 58.5% and 87.5% respectively. The activity of quercetin and vitamin E were substantiated by histopathological evaluation. Our study suggests that quercetin is an effective therapeutic agent for preventing hepatic tissues from oxidative stress resulting from streptozotocin-induced diabetes by inhibiting apoptotic processes in their target cells.

60 APPLIED LIFE SCIENCES↗