Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Accelerator Design”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,171 records · Page 65
All sourcesNASA NTRSDOE OSTI
NASA NTRS1993

The guide to Design For On-orbit Spacecraft Servicing (DFOSS) manual: Producing a consensus document

Increasing interaction and changing economies at the national and international levels have accelerated the call for standardization in space systems design. The benefits of standardization--compatibility, interchangeability, and lower costs--are maximized when achieved through consensus. Reaching consensus in standardization means giving everyone who will be affected by a standard an opportunity to have input into creating that standard. The DFOSS manual was initiated with the goal of developing standards through consensus. The present Proposed Guide derives from work begun by the Space Automation and Robotics Center (SpARC), a NASA Center for the Commercial Development of Space, and has continued as a standards project through the American Institute of Aeronautics and Astronautics (AIAA). The Proposed Guide was released by AIAA in Jan. 1992 for sale during a one-year, trial-use period. DFOSS is a response to the need for one document that contains all the guidelines required by on-orbit spacecraft servicing designers for astronaut extravehicular activity and/or telerobotic servicing. The manual's content is driven by spacecraft design considerations, and its composition has been achieved by interaction and cooperation among government, industry, and research organizations. While much work lies ahead to maximize the potential of DFOSS, the Proposed Guide represents evidence of the benefits of industry-wide consensus, points the way for broader application, and provides an example for similar projects.

Nyman, Janice↗
DOE OSTI2021

ACCELERATOR CHALLENGES OF THE LHeC PROJECT

The LHeC project studies the design of a future electron-proton collider at CERN that will run in parallel to the standard LHC operation. For this purpose, the existing LHC storage ring will be combined with an Energy Recovery Linac (ERL), to accelerate electrons up to kinetic energy of 50 GeV. This concept - also applicable to the FCC-eh collider and studied at the PERLE project as prototype version - allows a peak luminosity of 10³⁴ cm⁻² s⁻¹. A sophisticated design of the RF structures, linacs, arcs, and interaction region is required. The electrons are accelerated and, after the interaction point, their energy is recovered through the same RF structures. While this energy recovery concept is a very promising approach, severe challenges are set by the layout of the interaction region, the beam separation concept and the design of the linac and arc lattice for the highest possible momentum acceptance. Emittance control and beam-beam effect of both, electron and proton beams, have been studied in front-to-end simulations and will be presented. We summarise the design principles of the ERL, the optimization of the arc lattice, and the main parameters of the project.

Holzer, B. J.↗
DOE OSTI2025

Booster Cavity Damper Redesign for PIP-II

A new Higher Order Mode (HOM) damper was designed and tested for the Booster accelerator cavity at Fermilab. In anticipation of the PIP-II upgrade, it was discovered that the higher beam intensity of PIP-II may cause beam instability due to an excited mode at 106 MHz. This unfortunately corresponds with the cavity s 2nd order harmonic mode, which will sweep from 86-105.7 MHz. The new damper is a modification of an existing damper that was designed to reduce an existing static HOM at 83 MHz, with the new design intending to cover the 2nd order HOM as well. The existing damper uses an inductive coupling loop to extract RF energy from the cavity which then goes through a filter in order to reflect the fundamental frequency back into the cavity while passing HOMs to a dump load. The new damper intends to replace the filter portion of the system with a wider band variant while also changing the topology from a coaxial cable loop filter to a componentized PCB-based design. Primary design challenges include bandwidth coverage, impedance matching of the various modes, long term thermal and mechanical stability, radiation hardness, and high voltage handling. Initial designs achieved the desired damping but were found to quickly succumb to destructive arcing due to the voltages present. More finalized designs intend to address this problem through circuit design modifications as well as the use of hardier components.

Pieper, Dustin [Fermilab]↗
DOE OSTI2023

Accelerators for Electroweak Physics and Higgs Boson Studies

We discuss the goals, the designs, the state of technical readiness, and the critical R&D needs of the accelerators that are currently under discussion as Higgs and electroweak factories. We also address the respective staging options enabling future energy-frontier colliders. The accelerators covered are based on many different techniques and approaches. They include several circular colliders, various linear colliders, colliders based on energy recovery linacs (ERLs), ERL-ring combinations, as well as γγ colliders. The linear colliders proposed consist of options for the International Linear Collider (ILC), for the Compact Linear Collider (CLIC), for the Cold Copper Collider (C 3 ), and for the more recent Higgs-Energy Lepton Collider (HELEN). ERLs are key components of the Recycling Linear e + e - Collider (ReLiC),of the Energy Recovery Linear Collider (ERLC), and of the Circular Energy Recovery Collider (CERC). Among the more conventional ring colliders the following proposals are featured: the Future Circular Collider (FCC-ee), the Circular Electron Positron Collider (CEPC), the Electron Positron Circular Collider at Fermilab (EPCCF), and the Large Electron Positron collider #3 (LEP-3). In addition, we consider the X-ray FEL based gamma- gamma Collider Higgs Factory (XCC) and the High-Energy High-Luminosity γ-γ collider (HE&HL γγ). Finally, a Higgs factory based on a circular muon collider is mentioned for completeness.

43 PARTICLE ACCELERATORS↗
NASA NTRS2015

Aerodynamic Shape Optimization Benchmarks with Error Control and Automatic Parameterization

Results are presented for four optimization benchmark problems posed by the AIAA Aerodynamic Design Optimization Discussion Group. The benchmarks are intended to exercise optimization frameworks on representative airfoil and wing design problems. All problems involve drag minimization subject to geometric and aerodynamic constraints. Our design approach involves two forms of adaptation. First, the shape parameterization is gradually and automatically enriched from an initially coarse search space. Second, adjoint solutions are used to drive adaptive mesh refinement to control discretization error. The error threshold is tailored so that the nest meshes, with the greatest accuracy, are used only when nearing the optimum. On the inviscid airfoil design problem, while reducing the drag by a factor of 10, we show how the combination of progressive parameterization and tiered discretization error control can dramatically accelerate the optimization. On the viscous airfoil design problem, we use inviscid analysis-driven optimization to reduce the total drag by a factor of two. Next, we improve the span efficiency factor of a wing by performing twist optimization. Finally, we optimize the Common Research Model wing, managing to hold drag roughly fixed, while targeting an initially-violated pitching moment constraint. Our approach aims to introduce greater complexity and accuracy only when necessary to improve the design, and also support a greater degree of automation.

Anderson, George R.↗
DOE OSTI2020

Power Flow Spectroscopy Diagnostics & Platform Development at the Z Pulsed Power Facility

Large pulsed power accelerators deliver multi-MJ pulses of electrical energy to a variety of high energy density (HED) physics experiments that support stockpile science programs. Understanding the plasma formation mechanisms and resulting electrical power transport (or "power flow") in the vacuum magnetically insulated transmission lines (MITLs) is an important area of ongoing research, and could provide a means to improve the performance of today's pulsed power accelerators while improving confidence in the design options for next-generation pulsed power concepts. Power flow science has been studied for decades, but these studies have not provided a predictive understanding of plasma formation and expansion in MITL systems. Several recent factors in pulsed power system design have generated a renewed (and urgent) interest in developing validated, multi-physics power flow engineering models with increased scrutiny and understanding. Examples of these factors include (i) the use of high inductance experimental configurations that could increase current "loss", (ii) interest in long-pulse applications that require predictable pulse shapes, and (iii) the desire to develop a deeper understanding of how current loss phenomena scale to larger accelerator configurations. This work is directed to support the validation of multi-physics power flow engineering models required to realize pulsed power systems for the NNSA mission.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2021

Accelerating Binarized Neural Networks via Bit-Tensor-Cores in Turing GPUs

Despite foreseeing tremendous speedups over conventional deep neural networks, the performance advantage of binarized neural networks (BNNs) has merely been showcased on general-purpose processors such as CPUs and GPUs. In fact, due to being unable to leverage bit-level-parallelism with a word-based architecture, GPUs have been criticized for extremely low utilization (1%) when executing BNNs. Consequently, the latest tensorcores in NVIDIA Turing GPUs start to experimentally support bit computation. In this work, we look into this brand new bit computation capability and characterize its unique features. We show that the stride of memory access can significantly affect performance delivery and a data-format co-design is highly desired to support the tensorcores for achieving superior performance than existing software solutions without tensorcores. We realize the tensorcore-accelerated BNN design, particularly the major functions for fully-connect and convolution layers — bit matrix multiplication and bit convolution. Evaluations on two NVIDIA Turing GPUs show that, with ResNet-18, our BTC-BNN design can process ImageNet at a rate of 5.6K images per second, 77% faster than state-of-the-art. Our BNN approach is released on https://github.com/pnnl/TCBNN.

Li, Ang↗
DOE OSTI2020

Advanced Accelerator Technology (Final Report)

Superconducting radio-frequency (SRF) acceleration, together with high precision RF field control and high precision beam instrumentation and control, is a key technology for future next generation accelerators. In the past 10 years, significant progress on these technologies has been made jointly at KEK and US laboratories. The research progress summarized here is Cornell University’s contribution to a continued US-Japan collaborative accelerator research effort. The combined objectives of this collaboration were to solve critical technical issues related to SRF acceleration technology, related to low emittance beam generation, and related to reducing the vertical beam size of the ATF2 final focus beam line. These joint efforts significantly advance current accelerator technologies. The specific objective of the Cornell University part of this collaboration was to develop, in close connection with KEK and FNAL, new SRF cavity Nb3Sn thin-film coating technologies for transformational cavity performance. Cornell is a world leader in the synthesis of Nb3Sn for SRF application, and has produced the first-ever next-generation non-niobium (i.e., Nb 3 Sn) prototype SRF accelerator cavities with cryogenic efficiency exceeding that of traditional niobium cavities. These next-generation Nb 3 Sn SRF cavities strongly reduce AC power consumption of SRF based accelerators, and also enable using greatly simplified cryogenic cooling infrastructure, thereby making SRF technology available to a much wider range of accelerator applications. During this project, Cornell has designed and started fabrication of a new Nb 3 Sn coating setup, which will be large enough to coat full-scale (i.e., multi-cell) SRF accelerator cavities. In addition, Cornell University has participated in other collaborative activities at KEK and partner US laboratories.

43 PARTICLE ACCELERATORS↗
DOE OSTI2024

Exploratory splitter bend system designs for FFA@CEBAF

An upgrade to the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Facility (JLAB) is anticipated to provide an electron beam of over 20 GeV using the existing superconducting-RF linear accelerator and new fixed-field alternating (FFA) gradient recirculation arcs made up of Halbach-style permanent magnets. In the current design, the FFA arcs will carry six beams with energies of approximately 11, 13, 16, 18, 20, and 22 GeV which will require horizontal splitter lines to match the beam from the preceding linac. In this paper, we describe two alternative splitter beamline designs that are tuned to match the beam's Twiss parameters, R56, time-of-flight, bend-plane offset, and dispersion into the FFA cells.

Accelerator Physics↗
DOE OSTI2022

King City Asbestos Corporation (KCAC) Mine Carbon Mineralization Field Test (Final Combined Report)

The overall objective of the KCAC carbon mineralization project is to determine the most successful approaches to CO 2 mineralization of asbestos-bearing serpentinite rocks and mine waste at the closed KCAC asbestos mine. The objectives of Budget Period 1 (BP1) are to characterize the site including, mineralogical and geochemical variability in site materials, baseline conditions including CO 2 flux and local climate, and to establish the designs for the second, experimental phase of the project. As described in Section 3 of this report, all tasks outlined in the Statement of Project Objective (SOPO) have been completed or are on schedule to be completed by the end of BP1. As described in Section 4, all success criteria and milestones have been met or will be met by the end of BP1. We conclude that the findings of BP1 strongly support moving to the second phase of the project to investigate methods to increase the rate of CO 2 mineralization. CO 2 flux monitoring during BP1 established an estimated baseline uptake of CO 2 over the 142,193 m 2 KCAC mine site of 147 and 179 metric tons CO 2 /yr using dynamic closed chamber and eddy covariance monitoring methods, respectively. Mineralogical analysis shows that the loose surficial waste material contains pyroaurite and minor hydromagnesite, indicating past carbon mineralization. Sediment samples at depths below 60 cm contained ~3 wt% brucite and localized high brucite contents of ~24 wt% were measured at depth, indicating significant unreacted material at relatively shallow depths. Together, these results demonstrate that despite prolonged exposure to the atmosphere, reactive material is still present and accessible and is naturally taking up atmospheric CO 2 . However, these natural rates are still well below rates that can be achieved by applying practices that can accelerate the CO 2 mineralization reaction. Designs for the Field-Testing Phase (BP2) of the project have been established, incorporating the findings of BP1. Based on results to date we have selected two methods to accelerate the rate of CO 2 mineralization, which we refer to as the Tilling Method and the Greenhouse Method. We hypothesize that these methods can increase the CO 2 mineralization rate by up to 5 times greater than the natural background rate measured in BP1. An Initial Lifecyle Assessment (LCA) and techno-economic analysis (TEA) were conducted for these two methods. The LCA concluded that the baseline version of the Greenhouse and Tilling methods at commercial scale are expected to achieve a CDR efficiency of 97% and 71%, respectively (cumulative, over 30 years of operation). Incorporating the net CO 2 removal rates calculated in the LCA, the TEA found the levelized, 30-year costs of the baseline Greenhouse and Tilling methods to be $\$$95/t-CO 2 and $\$$119/t-CO 2 , respectively, and that costs could be brought to well below $\$$100/t-CO 2 for either method by scaling up the volume of rock utilized. An initial EH&S Risk Assessment, evaluating the potential EH&S risks of the proposed carbon mineralization methods at commercial scale, was completed by LLNL EH&S professionals for these two methods.

58 GEOSCIENCES↗
DOE OSTI2020

High-Throughput Analysis of Materials for Chemical Looping Processes

Chemical looping is a promising approach for improving the energy efficiency of many industrial chemical processes. However, a major limitation of modern chemical looping technologies is the lack of suitable active materials to mediate the involved subreactions. Identification of suitable materials has been historically limited by the scarcity of high-temperature (>600 °C) thermochemical data to evaluate candidate materials. An accuratethermodynamic approach is demonstrated here to rapidly identify active materials which is applicable to a wide variety of chemical looping chemistries. Application of this analysis to chemical looping combustion correctly classifies 17/17 experimentally studied redox materials by their viability and identifies over 1300 promising yet previously unstudied active materials. This approach is further demonstrated by analyzing redox pairs for mediating a novel chemical looping process for producing pure SO2 from raw sulfur and air which could provide a more efficient and lower emission route to sulfuric acid. 12 promising redox materials for this process are identified, two of which are supported by previous experimental studies of their individual oxidation and reduction reactions. This approach provides the necessary foundation for connecting process design with high-throughput material discovery to accelerate the innovation and development of a wide range of chemical looping technologies.

chemical looping↗
NASA NTRS2009

Particle Acceleration and Associated Emission from Relativistic Shocks

Five talks consist of a research program consisting of numerical simulations and theoretical development designed to provide an understanding of the emission from accelerated particles in relativistic shocks. The goal of this lecture is to discuss the particle acceleration, magnetic field generation, and radiation along with the microphysics of the shock process in a self-consistent manner. The discussion involves the collisionless shocks that produce emission from gamma-ray bursts and their afterglows, and producing emission from supernova remnants and AGN relativistic jets. Recent particle-in-cell simulation studies have shown that the Weibel (mixed mode two-stream filamentation) instability is responsible for particle (electron, positron, and ion) acceleration and magnetic field generation in relativistic collisionless shocks. 3-D RPIC code parallelized with MPI has been used to investigate the dynamics of collisionless shocks in electron-ion and electron-positron plasmas with and without initial ambient magnetic fields. In this lecture we will present brief tutorials of RPIC simulations and RMHD simulations, a brief summary of recent RPIC simulations, mechanisms of particle acceleration in relativistic shocks, and calculation of synchrotron radiation by tracing particles. We will discuss on emission from the collisionless shocks, which will be calculated during the simulation by tracing particle acceleration self-consistently in the inhomogeneous magnetic fields generated in the shocks. In particular, we will discuss the differences between standard synchrotron radiation and the jitter radiation that arises in turbulent magnetic fields.

Nishkawa, Ken-Ichi↗
DOE OSTI2023

A Novel Design for Improving the Control on the Stainless-Steel Vessel Welding Process for Superconducting Magnets

Stainless steel vessels see widespread use in superconducting magnets for particle accelerator applications. Their function varies in different magnet designs: they always provide the necessary liquid helium containment, but in some cases are also used to provide azimuthal prestress and can also be welded to the magnet end plate to provide additional longitudinal stiffness. A magnet designed with the bladder and key technology does not rely on the structural role of the vessel. They are structurally supported using azimuthally prestressed aluminum shells, and the longitudinal constraint by rods. In this case, the magnet designer would generally like to minimize the interaction between the magnet and the stainless-steel vessel and to minimize the coil stress variation due to the vessel. The stress state in the vessel and in the coil is a function of the circumferential interference, defined as the vessel azimuthal length minus the magnet circumference. The vessel and the magnet azimuthal length machining tolerances are relatively large resulting in significant stress variations in the superconducting coils. In this paper we introduce an interference control shim, which can significantly limit the stress variation of the coils for a given variation of the interference. The effectiveness of the interference-control shim is evaluated numerically on the MQXF, the low-β quadrupole for the High Luminosity LHC.

43 PARTICLE ACCELERATORS↗
DOE OSTI2024

When Machine Learning Meets 2D Materials: A Review

The availability of an ever-expanding portfolio of 2D materials with rich internal degrees of freedom (spin, excitonic, valley, sublattice, and layer pseudospin) together with the unique ability to tailor heterostructures made layer by layer in a precisely chosen stacking sequence and relative crystallographic alignments, offers an unprecedented platform for realizing materials by design. However, the breadth of multi-dimensional parameter space and massive data sets involved is emblematic of complex, resource-intensive experimentation, which not only challenges the current state of the art but also renders exhaustive sampling untenable. To this end, machine learning, a very powerful data-driven approach and subset of artificial intelligence, is a potential game-changer, enabling a cheaper – yet more efficient – alternative to traditional computational strategies. It is also a new paradigm for autonomous experimentation for accelerated discovery and machine-assisted design of functional 2D materials and heterostructures. Here, the study reviews the recent progress and challenges of such endeavors, and highlight various emerging opportunities in this frontier research area.

2D materials↗
DOE OSTI2022

Spin resonance canceling lattice cell design principles

We show how to construct an accelerator lattice cell which minimizes all intrinsic spin resonance. We then apply this approach to various toy electron and proton accelerators, considering, AGS-like and CEPC/FCC-ee and FCC-hh like rings.

43 PARTICLE ACCELERATORS↗
DOE OSTI2022

Accelerator Physics at NSLS-II: Research Accomplishments in 2022

NSLS-II accelerator physicists are working on scientific support of the NSLS-II operations and start-up of the accelerator systems including Storage Ring, Injector, beam diagnostics, and top-off injection; improvement of beam stability and orbit feedbacks; commissioning of a superconducting wiggler for the HEX beamline; development of a new operation mode for time-resolved experiments. The routine lattice characterization is continued to keep tracking the machine, the storage ring lattice model including strong coupling is developed, and seasonal variations of the ring circumference are studied. The collaboration with the EIC project is ongoing. In the frameworks of three LDRD projects, the physicists are working on the lattice development, studies of collective effects, and specifications of alignment and stability for the NSLS-II accelerator upgrade; novel methods of lattice design and optimization; studies of free-electron laser options; ultrafast electron diffraction and microscopy. Research accomplishments achieved in 2022, are summarized in this report.

43 PARTICLE ACCELERATORS↗
NASA NTRS1974

The influence of acceleration forces on nucleation, solidification, and deformation processes in tin single crystals

An apparatus was designed and assembled to directionally solidify single crystals under the influence of acceleration forces of various magnitudes. The investigation conducted showed that acceleration gradients produce a preferred growth orientation effect not previously observed for tin. Convection currents at approximately 5-g encourage multiple nucleation and subsequent random orientation of growth direction. Deformation effects such as recrystallization and twinning are observed at acceleration levels greater than 2-g.

Johnston, M. H.↗
DOE OSTI2026

PVDeg: Enhancing Usability and AI-Driven Multi-Mechanism Degradation Modeling

PVDeg version 0.7.0, released in December 2025, introduced major enhancements to improve usability and performance. This update reorganized tutorials and tool notebooks to create a more intuitive experience, enabling users to easily follow and adapt workflows for their specific analyses. In addition to structural improvements, both the notebooks and core logic underwent significant optimization for efficiency, robustness, and style. These refinements were supported by new testing frameworks built on nbval and pytest, adherence to PEP8 standards, and extensive code refactoring, which collectively simplify onboarding for new developers. Looking ahead, version 0.8.0 will deliver advanced AI-driven capabilities. The primary focus is to further develop and automate the degradation workflow, designed to analyze PV module degradation across diverse locations and system configurations. By integrating large language models (LLMs) to scan literature and compile a comprehensive database of materials and degradation rates, this feature will enable modeling of multiple materials and mechanisms within a single, streamlined workflow. Users will be able to evaluate degradation impacts on different system architectures under varying environmental conditions, facilitating informed decisions on bill-of-materials optimization for specific deployment scenarios. These advancements position PVDeg as a powerful, user-friendly tool for accelerating PV reliability research and system design.

14 SOLAR ENERGY↗