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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 343 records · Page 19
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Variable Permeability Magnetometer Systems and Methods for Aerospace Applications

A magnetometer configured to measure low field strength magnetic fields is provided. Certain embodiments of the magnetometer include a cylindrical coil assembly having a variable permeability core and terminals disposed at both ends. A current source circuit may be operably connected to the terminals and configured to apply a voltage controlled current across the terminals. A voltage readout circuit may be operably connected to the terminals and configured to measure a voltage across the terminals due to the applied current from the current source. An inductance of the coil assembly directly varies as an ambient magnetic field strength varies a permeability of the variable permeability core, and a voltage across the terminals varies directly with the inductance such that the measured voltage across the terminals is a direct measure of the ambient magnetic field strength.

Shams, Qamar A.↗
NASA NTRS2018

Permeability of a New Parachute Fabric – Measurements, Modeling, and Application

In response to a NASA request, Heathcoat Fabrics Limited has woven a new parachute fabric (Custom Design 1 G-60315-1800-Q01). This fabric was tested to obtain its permeability in air (i.e., flow-through volume of air per area per time) over a range of differential pressures from 0.146 to 25 psf (7 to 1197 Pa). The fabric met its specification permeability of 60 to 100 ft3/ft2/min (30.5 to 50.8 cm3/cm2/s) at the U.S. standard differential pressure of 0.5 inch of water (2.60 psf, 124 Pa). The permeability results were transformed into an effective porosity model for use in calculations related to the total porosity of parachutes. The tested fabric is being considered for use in parachutes for future missions to Mars. Calculations of drag coefficient were performed for two geometrically identical parachutes using either the new fabric or fabric woven to Parachute Industry Specification PIA-C-7020D Type I (Mars Science Laboratory Disk-Gap-Band parachute operating on Mars at a Mach number of 0.41). These calculations indicate essentially no difference in the drag coefficient between the two parachutes.

Cruz, Juan R.↗
DOE OSTI2019

The Determination of the Reaction Rates, Water Vapor Permeability, and Activation Energy for Thermal Oxidation of LDPE Films

To understand the mechanism of degradation of plastics under environmental degradation, thermal oxidation of LDPE thin film from a single manufacturer was studied. Oxidation was carried out in a pressure vessel with control at four temperatures( 22,50,70 and 80°C and at 30 and 50psi oxygen pressures. Cup tests were done to determine the permeability of water vapor across the LDPE film at 60, 70, and 90°C. The extent of oxidation was monitored using ATR-FTIR and the carbonyl content calculated from the spectra. Bands centered at 1711 and 1735 cm-1 was determined resulted from the carbonyl stretches. A broad band at 3100-3600cm -1 is attributed to O-H stretching and the fingerprint region (<1400 cm -1 ) shows evidence of C-O stretches. The permeability and carbonyl content to water vapor increased with temperature, oxidation time, and oxygen pressure. We concluded the observed increase to the result of the disruption of the semi-crystalline structure of the film to produce amorphous regions within which the water vapor is more permeable. This study was a step in the direction for determining a reliable model for the degradation and eventual failure of medium-level power cables in nuclear power plants (NPPs).

Munir, Nouman↗
DOE OSTI2024

Utah FORGE 5-2419: Seismicity-Permeability Relationships Probed via Nonlinear Acoustic Imaging - 2024 Annual Workshop Presentation

This is a presentation on Seismicity-Permeability Relationships Probed via Nonlinear Acoustic Imaging by Pennsylvania State University, presented by Derek Elsworth. This video slide presentation discussed controls and acoustic signatures of aseismic through seismic evolution of relocation-stability-permeability on fractures in shear-reactivation as a precursor to, and a key predictor of, seismic moment magnitude of prospective triggered-seismicity. This presentation was featured in the Utah FORGE R&D Annual Workshop on August 13, 2024.

15 GEOTHERMAL ENERGY↗
DOE OSTI2017

Highly Permeable Oligo(ethylene oxide)- co -poly(dimethylsiloxane) Membranes for Carbon Dioxide Separation

Here, a series of cross–linked, freestanding oligo(ethylene oxide)– co –(polydimethylsiloxane–norbornene) membranes with varied composition is synthesized via in situ ring–opening metathesis polymerization. These membranes show remarkably high CO 2 permeabilities (3400 Barrer) and their separation performance approaches the Robeson upper bound. The excellent permeability of these copolymer membranes provides great potential for real–world applications where enormous volumes of gases must be separated. The gas transport properties of these films are found to be directly proportional to oligo(ethylene oxide) content incorporation, which stems from the increased solubility selectivity change within the copolymer matrix. This work provides a systematic study of how gas separation performance in rubbery membranes can be enhanced by tuning the CO 2 –philicity of their constituent monomeric subunits.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Upscaling permeability for three-dimensional fractured porous rocks with the multiple boundary method

Upscaling permeability of grid blocks is crucial for groundwater models. A novel upscaling method for three-dimensional fractured porous rocks is presented. The objective of the study was to compare this method with the commonly used Oda upscaling method and the volume averaging method. First, the multiple boundary method and its computational framework were defined for three-dimensional stochastic fracture networks. Then, the different upscaling methods were compared for a set of rotated fractures, for tortuous fractures, and for two discrete fracture networks. The results computed by the multiple boundary method are comparable with those of the other two methods and fit best the analytical solution for a set of rotated fractures. The errors in flow rate of the equivalent fracture model decrease when using the multiple boundary method. Furthermore, the errors of the equivalent fracture models increase from well-connected fracture networks to poorly connected ones. Finally, the diagonal components of the equivalent permeability tensors tend to follow a normal or log-normal distribution for the well-connected fracture network model with infinite fracture size. By contrast, they exhibit a power-law distribution for the poorly connected fracture network with multiple scale fractures. The study demonstrates the accuracy and the flexibility of the multiple boundary upscaling concept. This makes it attractive for being incorporated into any existing flow-based upscaling procedures, which helps in reducing the uncertainty of groundwater models.

58 GEOSCIENCES↗
DOE OSTI2019

Application of Relatively High Permeability Fe-Si-Al Powder Cores to Common Mode Chokes

We have developed a novel common mode choke made of Fe-Si-Al powder core which exhibits relatively high permeability (μ{sub i}), up to 147, and high saturation magnetic induction (B{sub S}). A common mode choke made of Fe-Si-Al powder core exhibits good DC bias characteristics of common mode inductance because of the high B{sub S}. Furthermore, the common mode choke shows excellent impedance performance because of frequency stability of the μ{sub i}. It is concluded that relatively high permeability Fe-Si-Al powder core is suitable as a core material for common mode chokes in the work condition of big common mode currents and a wide frequency range (10 kHz–30 MHz).

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2021

Pozzolanic reactivity of natural pozzolans, ground glasses and coal bottom ashes and implication of their incorporation on the chloride permeability of concrete

It is well understood that the partial replacement of portland cement with pozzolans in sufficient proportions results in improved long-term performance of concrete. However, dwindling availability of the most widely used pozzolan in the construction industry, fly ash, is forecast due to the termination of coal-fired electricity power stations around the world, necessitating the exploration of alternative pozzolans. Experimental investigations are conducted to study the performance of traditional pozzolans such as fly ash, silica fume and natural pozzolans (metakaolin, pumice, perlite and lassenite) together with novel pozzolans, including ground glasses (high-alkali and low-alkali), and ground bottom ash. Twenty-one concrete mixtures are examined for compressive strength, electrical conductivity, electrical resistivity, chloride permeability, and chloride migration coefficient. The reactivity of pozzolans studied is also determined in terms of compressive strength in lime-pozzolan mortar using a modified lime-reactivity test method. Many of the materials tested demonstrate the potential to be used in place of fly ash. However, a wide variation in the performance of these materials is evident which highlights the need for a reliable test to determine the level of reactivity of a pozzolan. The results indicate that the 7-day strength in the modified lime-reactivity test provides a good indication of the pozzolanic reactivity of the material and of how the material can be expected to contribute to the strength and permeability of concrete. The use of electrical resistivity as an indicator of the performance of pozzolans in terms of strength development and chloride penetration resistance when used to partially replace portland cement in concrete is also discussed.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Impact of reservoir parameters and wellbore permeability uncertainties on CO 2 and brine leakage potential at the Shenhua CO 2 Storage Site, China

Here, this paper describes a system-level risk assessment for the Shenhua CO 2 storage site, China, using the National Risk Assessment Partnership Integrated Assessment Model for Carbon Storage (NRAP-IAM-CS). Here, we begin by determining the optimal number of Monte Carlo (MC) simulations to achieve CO 2 and brine leakage result convergence. Then, we calculate mass CO 2 and brine leakage to the atmosphere and a hypothetical shallow aquifer. Finally, we assess the geochemical impacts in the event of leakage as if there were a shallow freshwater aquifer at the Shenhua site. Simulation results show that leakage results tend to stabilize after 300 Monte Carlo simulations. When the three wells on site are assigned a permeability of 10 -11 m 2 (representing significantly leaking wells), moderate CO 2 and brine leakages occur, and the percentage of CO 2 leakage exceeds the threshold value we set based on the Intergovernmental Panel on Climate Change (IPCC). This is, however, unlikely to be the case for the Shenhua site. For all the other scenarios, the CO 2 leakage is trivial although there is still the possibility of CO 2 leakage into the groundwater aquifer exceeding the 1% threshold over 1000 years, assuming constant legacy wellbore permeability. For the significantly leaking scenario, there is a 10% probability to have a moderate (2.7 × 10 7 m 3 ) leakage-affected volume in the shallow aquifer with the pH below 6.5, and a large (1.4 × 10 8 m 3 ) volume with the total dissolved solids (TDS) above 500 ppm, hence pH and TDS may be considered for site monitoring plans. Based on the simulation results, there is a very low probability of significant CO 2 /brine leakage through the existing wells at the Shenhua CO 2 storage site.

58 GEOSCIENCES↗
DOE OSTI2020

Pore-scale simulation of gas flow in microscopic permeable media with complex geometries

Lattice Boltzmann method (LBM) is an efficient tool to perform direct numerical simulation of gas flow in micro-size pores. Despite great advances in LBM and its use in describing gas flow in micro-size channels in slip and transitional flow regimes, exploring formulations that are able to capture flow behavior in domains with complex boundary geometries remains a challenging task. As a result, the impact of complexities in pore structures on gas flow may not be fully explored using LBM. In this study, we propose to use the combined bounce-back and Maxwellian diffusive reflection scheme to capture the slip velocity with a new set of slip coefficients. Optimal values of slip coefficients are determined using a gradient based method, where the results from the linearized Boltzmann equation is used as the reference solution. The proposed formulation is further validated against predictions from molecular dynamics simulation in the presence of complex geometries by introducing obstacles of different shapes in straight channels. LBM with the proposed boundary treatment is then used to investigate gas flow in a synthetic microscopic permeable medium. Here, results indicate that gas exhibits different flow configurations as Knudsen number varies, and apparent gas permeability appears to have up to a second-order dependency on the reciprocal mean pressure in slip and transitional flow regimes.

03 NATURAL GAS↗
DOE OSTI2022

Permeability simulation of kidney-bean shaped carbon fibers

Cost saving efforts in carbon fiber manufacturing may result in irregularly shaped cross-sections, often as a kidney-bean shape. Here, in this research, flow simulations were performed to determine transverse permeability of these kidney-bean shaped fibers. Three different unit-cell packing arrangements for the kidney-bean shaped fibers and unit-cell orientations of 0°, + 90°, and – 90° were considered over the fiber volume fraction range 0.30 – 0.75. The kidney-bean shaped fibers had two distinct hexagonally packed unit-cell geometries because of the fiber’s asymmetry with different packing efficiency. The maximum fiber packing fraction for kidney-bean shaped fibers was 0.923, which was larger than the 0.907 for circular fibers. When compared to circular fibers with hexagonal packing, the kidney-bean shaped fibers had up to a 74% reduction in permeability. The ±90° orientations for KB-fibers with hexagonal packing had an infiltration time up to 3.86 longer than the hexagonal packed circular fibers for the same volume fraction.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Puromycin aminonucleoside increases podocyte permeability by modulating ZO-1 in an oxidative stress-dependent manner

Puromycin aminonucleoside (PAN)-induced nephrosis is a widely studied animal model of human idiopathic nephrotic syndrome because PAN injection into rats results in increased glomerular permeability with the characteristic ultrastructural changes in podocytes similar to human nephrosis. To investigate the role of zonula occludens (ZO)-1 and oxidative stress on PAN-induced podocyte phenotypical changes and hyperpermeability in vitro, we cultured rat and mouse podocytes and treated with various concentrations of PAN. PAN treatment increased oxidative stress level of podocytes significantly with the induction of Nox4. In addition, PAN changed the ultrastructure of podocytes, such as shortening and fusion of microvilli, and the separation of intercellular gaps, which were improved by anti-oxidative vitamin C and Nox4 siRNA. PAN also disrupted the intercellular linear ZO-1 staining and induced inner cytoplasmic re-localization of ZO-1 protein, resulting in increased podocyte intercellular permeability. PAN reduced ZO-1 protein amount and mRNA expression in a dose-dependent manner, which means that PAN could also modulate ZO-1 protein transcriptionally. However, the decreased ZO-1 protein of podocytes by PAN was improved by Nox4 siRNA transfection. Furthermore, vitamin C mitigated the quantitative and distributional disturbances of ZO-1 protein caused by PAN. Our results demonstrate that the phenotypical changes of intercellular ZO-1 by oxidative stress via Nox4 likely contribute to the glomerular hyperpermeability caused by PAN. - Highlights: • PAN increases ROS and induces the ultrastructural changes in podocytes. • Podocyte intercellular hyperpermeability by PAN is via oxidative stress in vitro. • PAN induces the inner cytoplasmic relocalization of intercellular ZO-1 in podocytes. • PAN suppresses the production of ZO-1 protein at the transcriptional level. • The quantitative and distributional changes of ZO-1 by PAN are via oxidative stress.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

Three-Dimensional Microphase Separation and Synergistic Permeability in Stacked Lipid–Polymer Hybrid Membranes

Here, we present new structures of soft-material thin films that augment the functionality of substrate-mediated delivery systems. A hybrid material composed of phospholipids and block copolymers adopts a multilayered membrane structure supported on a solid surface. The hybrid films comprise intentional intramembrane heterogeneities that register across multilayers. These stacked domains convey unprecedented enhancement and control of permeability of solutes across micrometer-thick films. Using grazing incidence X-ray scattering, phase contrast atomic force microscopy, and confocal microscopy, we observed that in each lamella, lipid and polymers partition unevenly within the membrane plane segregating into lipid- or polymer-rich domains. Interestingly, we found evidence that like-domains align in registry across multilayers, thereby making phase separation three-dimensional. Phase boundaries exist over extended length scales to compensate the height mismatch between lipid and polymer molecules. We show that microphase separation in hybrid films can be exploited to augment the capability of drug-eluting substrates. Lipid–polymer hybrid films loaded with paclitaxel show synergistic permeability of drug compared to single-component counterparts. We present a thorough structural study of stacked lipid–polymer hybrid membranes and propose that the presence of registered domains and domain boundaries impart enhanced drug release functionality. This work offers new perspectives in designing thin films for controlled delivery applications

36 MATERIALS SCIENCE↗
DOE OSTI2016

Numerical Simulation of Permeability Change in Wellbore Cement Fractures after Geomechanical Stress and Geochemical Reactions Using X-ray Computed Tomography Imaging

X-ray microtomography (XMT) imaging combined with a three-dimensional (3D) computational fluid dynamics (CFD) modeling technique was used to study the effect of geochemical and geomechanical processes on fracture properties in composite Portland cement–basalt caprock core samples. The effect of fluid properties and flow conditions on fracture permeability was numerically studied by using fluids with varying physical properties and simulating different pressure conditions. CFD revealed that the application of geomechanical stress led to increased fluid flow, which resulted in increased fracture permeability. After CO2-reaction, XMT images displayed preferential precipitation of calcium carbonate within the fractures in the cement matrix and less precipitation in fractures located at the cement–basalt interface. CFD predicted changes in flow characteristics and differences in absolute values of flow properties due to different pressure gradients. CFD was able to highlight the profound effect of fluid properties on flow characteristics and hydraulic properties of fractures. This study demonstrates the applicability of XMT imaging and CFD as powerful tools for characterizing the hydraulic properties of fractures in a number of applications like geologic carbon sequestration and storage, hydraulic fracturing for shale gas production, and enhanced geothermal systems.

CO2 storage↗
DOE OSTI2018

Membrane Permeability of Terpenoids Explored with Molecular Simulation

We report that terpenoids constitute a class of compounds with remarkable potential for pharmaceutical, fragrance, specialty chemical, and biofuel applications. However, their industrial production is limited by their rarity within their native plant hosts, creating considerable interest in microbial hosts capable of manufacturing terpenoids. To reduce production costs, nondestructive product recovery from these microbial hosts is preferred, and is achievable using a hydrophobic organic overlay. Our prior research has indicated that oxidized fatty acyl products may permeate faster through host membranes, increasing overall biorefinery productivity. To test this hypothesis for terpenoids, we computed membrane permeabilities of conventional terpenoid target products (e.g., limonene, bisabolene, farnesene) and related oxidized compounds through molecular dynamics simulations. These simulations indicate that terpenoid product permeabilities from cytosol to overlay are oxidation independent, as increases in membrane extraction efficiency due to product oxidation are proportionally offset by decreases in the membrane crossing rate if the membrane and organic phase are in close contact. However, if aqueous extraction is required, oxidation will accelerate the slow product extraction from the membrane. Experimental toxicity assays performed indicated that most terpenoids tested were tolerated by microbial hosts, although exposure to oxidized terpenes often retarded microbial growth compared with conventional terpenes. Finally, terpenoid oxidation is not expected to significantly increase or decrease the extraction productivity in an industrial setting where cells are in close contact, unlike the previously studied fatty acyl products.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Universal Relationship Between Viscous and Inertial Permeability of Geologic Porous Media

Fluid flow through geologic porous media is reflected by Darcy's law and its inertial and nonlinear extension, the Forchheimer equation. These relationships equate the product of the driving potential gradient and phenomenological coefficients representing momentum resistance and dissipation to flux. From decades of research, the coefficient of viscous permeability (k v ) in Darcy's law is largely predictable, but this is not the case for the coefficient of inertial permeability (k i ) in the Forchheimer equation. Synthesizing results from thousands of laboratory and field flow tests and pore-scale flow model results, we demonstrate that k i can be predicted from k v via the equation k i = 10 10 k v 3/2 across 12 and 20 orders of magnitude in k v and k i , respectively. Since it is related with k i , k v is thus sufficient for predicting flow across viscous to inertial regimes for most geologic porous media.

58 GEOSCIENCES↗
DOE OSTI2019

Tracer-Guided Characterization of Dominant Pore Networks and Implications for Permeability and Wettability in Shale

Pore network characterization is an important aspect in unconventional reservoir evaluation. While application of the technique of scanning electron microscope (SEM) brings substantial advances in pore characterization in shale, understanding the connected pore network that dominates flow in shale samples is limited by using SEM alone because of small fields of view and lack of views of connectivity in 3D. In this research, a technique integrating tracer imbibition, micro-computed tomography (CT) imaging, and SEM imaging was developed to provide a solution for multiscale imaging in shale. Tracer imbibition indicates pore connectivity; micro-CT imaging after tracer imbibition thus provides an overview of the connected pore network at the millimeter scale. With guidance from micro-CT images after tracer imbibition, a more accurate and detailed characterization of pore systems and related mineralogy can be conducted using higher-resolution SEM. The method was applied to five samples from Wolfcamp and Eagle Ford Formations. Results reveal the effectiveness of the integrated method by showing different patterns of distribution of the dominant pore network and different controlling mineralogy. Dominant porosity, estimated from grayscale analyses, displays a good correlation with permeability. This result indicates that dominant porosity is more relevant to permeability than is total porosity. Results from imbibition tests are also compared with that from contact angle measurement, and important implications on wettability can be obtained. The integrated method thus has the capacity to link the dominant pore network and wettability with microscale to submicroscale mineralogy, which can help better understand the pore systems and fluid flow in shale. Plain Language Summary Pore network characterization and wettability are two important aspects in unconventional reservoir evaluation and are crucial to understanding the nature of shale oil or gas storage and production. Here, a new technique integrating tracer imbibition, micro-computed tomography imaging, and scanning electron microscope imaging was developed for a more representative and effective pore characterization in shale. This integrated technique can provide a direct visualization of the dominant pore network in a millimeter-scale sample and, at the same time, can provide a guided pore network characterization under nanoscale resolution. This method thus can generate results that are more representative and more accurate in a more efficient way compared with the traditional scanning electron microscope method. The new technique can also reveal the local wettability in microscale. High-resolution analysis on the tracer imbibition or fluid displacement and mineralogy can shed light on the local wettability and the controlling mineralogy in shale.

58 GEOSCIENCES↗
DOE OSTI2013

Negative permittivity and permeability spectra of Cu/yttrium iron garnet hybrid granular composite materials in the microwave frequency range

The relative complex permittivity and permeability spectra of the coagulated copper and yttrium iron garnet (Cu/YIG) hybrid granular composite materials have been studied in the microwave range. The insulator to metal transition was observed at the percolation threshold of Cu particle content (φ{sub Cu} = 16.0 vol. %) in the electrical conductivity. In the percolation threshold, the low frequency plasmonic state caused by the metallic Cu particle networks was observed. The percolated Cu/YIG granular composites show simultaneous negative permittivity and permeability spectra under external magnetic fields.

36 MATERIALS SCIENCE↗