Water resource assessment of geothermal resources and water use in geopressured geothermal systems. (open access)

Water resource assessment of geothermal resources and water use in geopressured geothermal systems.

None
Date: March 11, 2013
Creator: Clark, C. E.; Harto, C. B. & Troppe, W. A.
Object Type: Report
System: The UNT Digital Library
Laboratory Directed Research and Development FY2012 Annual Report (open access)

Laboratory Directed Research and Development FY2012 Annual Report

None
Date: March 11, 2013
Creator: Craig, W. W.; Sketchley, J. A. & Kotta, P. R.
Object Type: Report
System: The UNT Digital Library
Advanced Combustion (open access)

Advanced Combustion

The activity reported in this presentation is to provide the mechanical and physical property information needed to allow rational design, development and/or choice of alloys, manufacturing approaches, and environmental exposure and component life models to enable oxy-fuel combustion boilers to operate at Ultra-Supercritical (up to 650{degrees}C & between 22-30 MPa) and/or Advanced Ultra-Supercritical conditions (760{degrees}C & 35 MPa).
Date: March 11, 2013
Creator: Holcomb, Gordon R.
Object Type: Article
System: The UNT Digital Library
U.S. Department of Energy Hydrogen Storage Cost Analysis (open access)

U.S. Department of Energy Hydrogen Storage Cost Analysis

The overall objective of this project is to conduct cost analyses and estimate costs for on- and off-board hydrogen storage technologies under development by the U.S. Department of Energy (DOE) on a consistent, independent basis. This can help guide DOE and stakeholders toward the most-promising research, development and commercialization pathways for hydrogen-fueled vehicles. A specific focus of the project is to estimate hydrogen storage system cost in high-volume production scenarios relative to the DOE target that was in place when this cost analysis was initiated. This report and its results reflect work conducted by TIAX between 2004 and 2012, including recent refinements and updates. The report provides a system-level evaluation of costs and performance for four broad categories of on-board hydrogen storage: (1) reversible on-board metal hydrides (e.g., magnesium hydride, sodium alanate); (2) regenerable off-board chemical hydrogen storage materials(e.g., hydrolysis of sodium borohydride, ammonia borane); (3) high surface area sorbents (e.g., carbon-based materials); and 4) advanced physical storage (e.g., 700-bar compressed, cryo-compressed and liquid hydrogen). Additionally, the off-board efficiency and processing costs of several hydrogen storage systems were evaluated and reported, including: (1) liquid carrier, (2) sodium borohydride, (3) ammonia borane, and (4) magnesium hydride. TIAX applied a “bottom-up” costing …
Date: March 11, 2013
Creator: Law, Karen; Rosenfeld, Jeffrey; Han, Vickie; Chan, Michael; Chiang, Helena & Leonard, Jon
Object Type: Report
System: The UNT Digital Library
An Energy Principle for Ideal MHD Equilibria with Flows (open access)

An Energy Principle for Ideal MHD Equilibria with Flows

In the standard ideal MHD energy principle for equilibria with no flows, the stability criterion, which is the defi niteness of the perturbed potential energy, is usually constructed from the linearized equation of motion. Equivalently while more straightforwardly, it can also be obtained from the second variation of the Hamiltonian calculated with proper constraints. For equilibria with flows, a stability criterion was proposed from the linearized equation of motion, but not explained as an energy principle1. In this paper, the second variation of the Hamiltonian is found to provide a stability criterion equivalent to, while more straightforward than, what was constructed from the linearized equation of motion. To calculate the variations of the Hamiltonian, a complete set of constraints on the dynamics of the perturbations is derived from the Euler-Poincare structure of the ideal MHD. In addition, a previous calculation of the second variation of the Hamiltonian was claimed to give a different stability criterion2, and in this paper we argue such a claim is incorrect.
Date: March 11, 2013
Creator: Qin, Yao Zhou and Hong
Object Type: Report
System: The UNT Digital Library