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Results for “permeability”

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 199 records · Page 11

Low permeability polybenzimidazole (PBI) gel membranes for redox flow batteries

Disclosed are redox flow battery membranes, redox flow batteries incorporating the membranes, and methods of forming the membranes. The membranes include a densified polybenzimidazole gel membrane that is capable of incorporating a high liquid content without loss of structure that is formed according to a process that includes in situ hydrolysis of a polyphosphoric acid solvent followed by densification of the gel membrane. The densified membranes are then imbibed with a redox flow battery supporting electrolyte such as sulfuric acid and can operate at very high ionic conductivities of about 50 mS/cm or greater and with low permeability of redox couple ions, e.g. vanadium ions, of about 10−7 cm2/s or less. Redox flow batteries incorporating the membranes can operate at current densities of about 50 mA/cm2 or greater.

Benicewicz, Brian C.↗

Gas permeable fluoropolymers and ionomers

Novel copolymers that are fluoropolymers including a first repeat unit that is fluorinated and cyclic and a second repeat unit from a trifluorovinyl methylene ether monomer having sulfur or sulfone functionality in the pendant group are disclosed. The copolymers have relatively high gas permeability as a result of a cyclic repeat unit in the copolymer backbone and ionomers from oxidation of the sulfur containing functionality are particularity useful in the cathode structure of a proton exchange membrane fuel cell.

Lousenberg, Robert Daniel↗

MPLBM-UT: Multiphase LBM library for permeable media analysis

MPLBM-UT is a specialized lattice-Boltzmann library that makes running single- and two-phase flow simulations in porous media accessible to everyone. We provide a suite of tools to pre-process computational domains for simulation, to set up custom boundary conditions, to run simulations, to post-process simulation outputs, and to visualize simulation results and data. All of these tools are easily accessible to users through the mplbm_utils Python package included in and automatically installed with MPLBM-UT. The high-performance, highly parallel library Palabos is used as the solver backend. MPLBM-UT is easily deployed in a variety of systems, from laptops to supercomputer clusters. MPLBM-UT also features multiple examples and benchmark templates that allow for fast prototyping of different porous media problems. We also provide an interface for reading in different file types and downloading domains from the Digital Rocks Portal to perform simulations.

97 MATHEMATICS AND COMPUTING↗

Utah FORGE Friction-Permeability-Seismicity Laboratory Experiments with Non-Linear Acoustics

Laboratory experimental data on saw-cut interface of Westerly Granite and Utah Forge granitoid rocks. Experiments include velocity-stepping and fluid pressure stepping experiments. Mechanical data from 3 ISCO pumps connected to a Temco pressure vessel measure axial, confining and fault: fluid pressure (kPa), fluid flow rate (mL/min) and volume remaining in pump (mL). Non-linear acoustic data acquired via Verasonics systems connected to PZTs inside the pressure vessel give the timeshift, amplitude and RMS amplitude of the passing P-wave.

15 GEOTHERMAL ENERGY↗

Efficacy of underground aggregate infiltration beds under a permeable pavement system

Urban areas often face significant flooding challenges due to impermeable surfaces that exacerbate stormwater runoff, making effective stormwater management essential. This study demonstrated that combining pervious concrete pavement systems with underground aggregate storage beds and rain gardens can significantly enhance water infiltration and drainage efficiency, providing valuable insights for designing low-impact development strategies in flood-prone regions.

Haselbach, Liv [Lamar Univ., Beaumont, TX (United ↗