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Comparative shock response of additively manufactured versus conventionally wrought 304L stainless steel

AIP Conference Proceedings

Wise, Jack L.; Adams, David P.; Nishida, E.E.; Song, Bo S.; Maguire, M.C.; Carroll, Jay D.; Reedlunn, Benjamin R.; Bishop, Joseph E.; Palmer, T.A.

Gas-gun experiments have probed the compression and release behavior of impact-loaded 304L stainless steel specimens that were machined from additively manufactured (AM) blocks as well as baseline ingot-derived bar stock. The AM technology permits direct fabrication of net-or near-net-shape metal parts. For the present investigation, velocity interferometer (VISAR) diagnostics provided time-resolved measurements of sample response for onedimensional (i.e., uniaxial strain) shock compression to peak stresses ranging from 0.2 to 7.0 GPa. The acquired waveprofile data have been analyzed to determine the comparative Hugoniot Elastic Limit (HEL), Hugoniot equation of state, spall strength, and high-pressure yield strength of the AM and conventional materials. The possible contributions of various factors, such as composition, porosity, microstructure (e.g., grain size and morphology), residual stress, and/or sample axis orientation relative to the additive manufacturing deposition trajectory, are considered to explain differences between the AM and baseline 304L dynamic material results.

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TYPE Conference Poster YEAR 2017
ScopusOSTI

Applications of polyhedral finite elements in solid mechanics

Generalized Barycentric Coordinates in Computer Graphics and Computational Mechanics

Bishop, Joseph E.

The finite element method has revolutionized structural analysis since its inception over 50 years ago, by enabling the computer analysis of geometrically complex structures. The main requirement of the finite element method is that an appropriate partition, or mesh, of the structure be created first. The elements of the partition typically have standard shapes, such as the hexahedron, pentahedron, and tetrahedron. While this small library of standard element shapes is sufficient for many applications, there is a growing need for more general polyhedral shapes, ones that can have an arbitrary number of vertices, edges, and faces, and ones that can be non-convex. In this chapter, we discuss current and possible future applications of polyhedral finite elements in solid mechanics. These applications include rapid engineering analysis through novel meshing and discretization techniques, and fracture and fragmentation modeling. Several finite element formulations of general polyhedra have been developed. In this chapter we use a polyhedral formulation based on the use of harmonic shape functions. Harmonic shape functions are one example of several possible generalized barycentric coordinates, as discussed in Chapter 1.

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TYPE Book YEAR 2017
ScopusOSTI

Investigation of the influence of geomechanical and hydrogeological properties on surface uplift at In Salah [Systematic investigation of the influence of geomechanical and hydrogeological properties on surface uplift at In Salah]

Journal of Petroleum Science and Engineering

Newell, Pania N.; Yoon, Hongkyu Y.; Martinez, Mario J.; Bishop, Joseph E.; Bryant, Steven B.

Coupled reservoir and geomechanical simulations are significantly important to understand the long-term behavior of geologic carbon storage (GCS) systems. In this study, we performed coupled fluid flow and geomechanical modeling of CO2 storage using available field data to (1) validate our existing numerical model and (2) perform parameter estimation via inverse modeling to identify the impact of key geomechanical (Young's modulus and Biot's coefficient) and hydrogeological (permeability and anisotropy ratio) properties on surface uplift and the pore pressure buildup at In Salah in Algeria. Furthermore, two sets of surface uplift data featuring low and high uplifts above two injection wells and the maximum change in the pore pressure due to CO2 injection were used to constrain the inverse model.

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TYPE Journal Article YEAR 2016
OSTIDOI
Results 76–100 of 230
Results 76–100 of 230