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Electromagnetic analysis of Forces and torques on the baseline and enhanced ITER shield modules due to plasma disruption

IEEE Transactions on Plasma Science

Kotulski, Joseph D.; Coats, Rebecca S.; Pasik, Michael F.; Ulrickson, M.A.

An electromagnetic analysis is performed on the ITER shield modules under different plasma-disruption scenarios using the OPERA-3d software. The models considered include the baseline design as provided by the International Organization and an enhanced design that includes the more realistic geometrical features of a shield module. The modeling procedure is explained, electromagnetic torques are presented, and results of the modeling are discussed. © 2010 IEEE.

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Computational study of the electromagnetic forces and torques on different ITER first wall designs

Proceedings - Symposium on Fusion Engineering

Kotulski, J.D.; Coats, Rebecca S.; Pasik, Michael F.; Ulrickson, M.A.; Garde, J.

An electromagnetic analysis is performed on different first wall designs for the ITER device. The electromagnetic forces and torques present due to a plasma disruption event are calculated and compared for the different designs.

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Electromagnetic analysis of forces and torques on the ITER shield modules due to plasma disruption

Proceedings - Symposium on Fusion Engineering

Kotulski, J.D.; Coats, Rebecca S.; Pasik, Michael F.; Ulrickson, M.A.

An electromagnetic analysis is performed on the ITER shield modules under different plasma disruption scenarios using the OPERA-3d software. The modeling procedure is explained, electromagnetic torques are presented, and results of the modeling are discussed.

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Electromagnetic analysis of transient disruption forces on the ITER shield modules

Fusion Engineering and Design

Kotulski, J.D.; Coats, Rebecca S.; Pasik, Michael F.

This paper describes the eddy current computation and the resultant forces and torques on selected shield modules assigned to the US team that occur due to plasma disruption. The plasma disruption considered is referred to as major disruption (MD) and is one of the disruption cases defined by the International Organization (IO). This paper identifies the applicability of geometrical simplifications for future design analyses. In particular it is shown that cutting a module in half does not preserve the physics of the eddy current generation and resultant calculations while modeling a full module including the nearest modules does preserve the fundamental physics. The force results are shown for shield modules 7 and 13 exposing the validity of geometrical simplifications. The computed torque for these two modules is also presented. © 2008 Elsevier B.V.

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Transient electromagnetic modeling of the ZR accelerator water convolute and stack

Digest of Technical Papers-IEEE International Pulsed Power Conference

Pasik, Michael F.; Coats, Rebecca S.; Johnson, William Arthur.; Elizondo-Decanini, Juan M.; Pointon, Timothy D.; Turner, C.D.; Bohnhoff, William J.; Lehr, J.M.; Savage, Mark E.

The ZR accelerator is a refurbishment of Sandia National Laboratories Z accelerator [1]. The ZR accelerator components were designed using electrostatic and circuit modeling tools. Transient electromagnetic modeling has played a complementary role in the analysis of ZR components [2]. In this paper we describe a 3D transient electromagnetic analysis of the ZR water convolute and stack using edge-based finite element techniques. © 2005 IEEE.

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Electromagnetic analysis of transient forces due to disrupted plasma currents on the ITER shield modules

Proceedings - Symposium on Fusion Engineering

Kotulski, J.D.; Coats, Rebecca S.; Pasik, Michael F.

This paper describes the electromagnetic analysis that has been completed using the OPERA-3d product to characterize the folces on the ITER shield modules as part of the conceptual design. These forces exist due to the interaction of the eddy currents induced in the shield modules and the large magnetic fields present in the tokamak. ©2007 IEEE.

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Copy of An overview of pulse compression and power flow in the upgraded Z pulsed power driver

Savage, Mark E.; Maenchen, John E.; McDaniel, Dillon H.; Pasik, Michael F.; Pointon, Timothy D.; Owen, Albert C.; Seidel, David B.; Stoltzfus, Brian S.; Struve, Kenneth W.; Warne, Larry K.; Bennett, Lawrence F.; Woodworth, Joseph R.; Bliss, David E.; Clark, Waylon T.; Coats, Rebecca S.; Elizondo-Decanini, Juan M.; LeChien, Keith R.; Harjes, Henry C.; Lehr, J.M.

Abstract not provided.

Model for resonant plasma probe

Johnson, William Arthur.; Coats, Rebecca S.; Jorgenson, Roy E.; Hebner, Gregory A.

This report constructs simple circuit models for a hairpin shaped resonant plasma probe. Effects of the plasma sheath region surrounding the wires making up the probe are determined. Electromagnetic simulations of the probe are compared to the circuit model results. The perturbing effects of the disc cavity in which the probe operates are also found.

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Emphasis/Nevada STDEM : user's guide : version 1.0

Coats, Rebecca S.; Pasik, Michael F.; Seidel, David B.

STDEM is the structured mesh time-domain electromagnetic and plasma physics component of Emphasis/Nevada. This report provides a guide on using STDEM. Emphasis, the electromagnetic physics analysis system, is a suite of codes for the simulation of electromagnetic and plasma physics phenomena. The time-dependent components of Emphasis have been implemented using the Nevada framework [1]. The notation Emphasis/Nevada is used to highlight this relationship and/or distinguish the time-dependent components of Emphasis. In theory the underlying framework should have little influence on the user's interaction with the application. In practice the framework tends to be more invasive as it provides key services such as input parsing and defines fundamental concepts and terminology. While the framework offers many technological advancements from a software development point of view, from a user's perspective the key benefits of the underlying framework are the common interface for all framework physics modules as well as the ability to perform coupled physics simulations. STDEM is the structured time-domain electromagnetic and plasma physics component of Emphasis/Nevada. STDEM provides for the full-wave solution to Maxwell's equations on multi-block three-dimensional structured grids using finite-difference time-domain (FDTD) algorithms. Additionally STDEM provides for the fully relativistic, self-consistent simulation of charged particles using particle-in-cell (PIC) algorithms.

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Electromagnetic analysis and modeling of the coax-to-triplate transition for the pulse-compression section of the ZR accelerator

Digest of Technical Papers-IEEE International Pulsed Power Conference

Johnson, William Arthur.; Coats, Rebecca S.; Jorgenson, Roy E.; Kotulski, J.D.; Lehr, J.M.; Pasik, Michael F.; Rosenthal, Stephen E.; Turner, C.D.; Warne, Larry K.

Transverse electromagnetic (TEM) wave analysis is used to estimate the efficiencies of the coax to triplate transition in Sandia's Z-20 test module. The structure of both the TEM mode and higher order TE modes in the triplate transmission line are characterized. In addition, three dimensional time domain simulations are carried out and used in conjunction with the modal analysis to provide insight into the wave structure excited in the triplate transmission line.

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Load-balancing techniques for a parallel electromagnetic particle-in-cell code

Plimpton, Steven J.; Seidel, David B.; Pasik, Michael F.; Coats, Rebecca S.

QUICKSILVER is a 3-d electromagnetic particle-in-cell simulation code developed and used at Sandia to model relativistic charged particle transport. It models the time-response of electromagnetic fields and low-density-plasmas in a self-consistent manner: the fields push the plasma particles and the plasma current modifies the fields. Through an LDRD project a new parallel version of QUICKSILVER was created to enable large-scale plasma simulations to be run on massively-parallel distributed-memory supercomputers with thousands of processors, such as the Intel Tflops and DEC CPlant machines at Sandia. The new parallel code implements nearly all the features of the original serial QUICKSILVER and can be run on any platform which supports the message-passing interface (MPI) standard as well as on single-processor workstations. This report describes basic strategies useful for parallelizing and load-balancing particle-in-cell codes, outlines the parallel algorithms used in this implementation, and provides a summary of the modifications made to QUICKSILVER. It also highlights a series of benchmark simulations which have been run with the new code that illustrate its performance and parallel efficiency. These calculations have up to a billion grid cells and particles and were run on thousands of processors. This report also serves as a user manual for people wishing to run parallel QUICKSILVER.

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Results 51–71 of 71
Results 51–71 of 71