Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “ignition system”

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 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
DOE OSTI2011

Performance Improvements to the Neutron Imaging System at the National Ignition Facility

A team headed by LANL and including many members from LLNL and NSTec LO and NSTec LAO fielded a neutron imaging system (NIS) at the National Ignition Facility at the start of 2011. The NIS consists of a pinhole array that is located 32.5 cm from the source and that creates an image of the source in a segmented scintillator 28 m from the source. The scintillator is viewed by two gated, optical imaging systems: one that is fiber coupled, and one that is lens coupled. While there are a number of other pieces to the system related to pinhole alignment, collimation, shielding and data acquisition, those pieces are discussed elsewhere and are not relevant here. The system is operational and has successfully obtained data on more that ten imaging shots. This remainder of this whitepaper is divided in five main sections. In Section II, we identify three critical areas of improvement that we believe should be pursued to improve the performance of the system for future experiments: spatial resolution, temporal response and signal-to-noise ratio. In Section III, we discuss technologies that could be used to improve these critical performance areas. In Section IV, we describe a path to evolve the current system to achieve improved performance with minimal impact on the ability of the system to operate on shots. In Section V, we discuss the abilities, scope and timescales of the current teams and the Commissariat energie atomique (CEA). In Section VI, we summarize and make specific recommendations for collaboration on improvements to the NIS.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2011

Use of the target diagnostic control system in the National Ignition Facility

The extreme physics of targets shocked by NIF's 192-beam laser are observed by a diverse suite of diagnostics including optical backscatter, time-integrated, time resolved and gated X-ray sensors, laser velocity interferometry, and neutron time of flight. Diagnostics to diagnose fusion ignition implosion and neutron emissions have been developed. A Diagnostic Control System (DCS) for both hardware and software facilitates development and eases integration. Each complex diagnostic typically uses an ensemble of electronic instruments attached to sensors, digitizers, cameras, and other devices. In the DCS architecture each instrument is interfaced to a low-cost Window XP processor and Java application. Instruments are aggregated as needed in the supervisory system to form an integrated diagnostic. The Java framework provides data management, control services and operator GUI generation. During the past several years, over thirty-six diagnostics have been deployed using this architecture in support of the National Ignition Campaign (NIC). The DCS architecture facilitates the expected additions and upgrades to diagnostics as more experiments are performed. This paper presents the DCS architecture, framework and our experiences in using it during the NIC to operate, upgrade and maintain a large set of diagnostic instruments.

42 ENGINEERING↗
DOE OSTI2017

Control and Information Systems for the National Ignition Facility

Orchestration of every National Ignition Facility (NIF) shot cycle is managed by the Integrated Computer Control System (ICCS), which uses a scalable software architecture running code on more than 1950 front-end processors, embedded controllers, and supervisory servers. The ICCS operates laser and industrial control hardware containing 66 000 control and monitor points to ensure that all of NIF’s laser beams arrive at the target within 30 ps of each other and are aligned to a pointing accuracy of less than 50 μm root-mean-square, while ensuring that a host of diagnostic instruments record data in a few billionths of a second. NIF’s automated control subsystems are built from a common object-oriented software framework that distributes the software across the computer network and achieves interoperation between different software languages and target architectures. A large suite of business and scientific software tools supports experimental planning, experimental setup, facility configuration, and post-shot analysis. Standard business services using open-source software, commercial workflow tools, and database and messaging technologies have been developed. An information technology infrastructure consisting of servers, network devices, and storage provides the foundation for these systems. Thus, this work is an overview of the control and information systems used to support a wide variety of experiments during the National Ignition Campaign.

42 ENGINEERING↗
DOE OSTI2021

Investigating anode off-gas under spark-ignition combustion for SOFC-ICE hybrid systems

Solid oxide fuel cell – internal combustion engine (SOFC-ICE) hybrid systems are an attractive solution for electricity generation. The system can achieve up to 70% theoretical electric power conversion efficiency through energy cascading enabled by utilizing the anode off-gas from the SOFC as the fuel source for the ICE. Experimental investigations were conducted with a single cylinder Cooperative Fuel Research (CFR) engine by altering fuel-air equivalence ratio (φ), and compression ratio (CR) to study the engine load, combustion characteristics, and emissions levels of dry SOFC anode off-gas consisting of 33.9% H 2 , 15.6% CO, and 50.5% CO 2 . The combustion efficiency of the anode off-gas was directly evaluated by measuring the engine-out CO emissions. The highest net-indicated fuel conversion efficiency of 31.3% occurred at φ = 0.90 and CR = 13:1. These results demonstrate that the anode off-gas can be successfully oxidized using a spark ignition combustion mode. The fuel conversion efficiency of the anode tail gas is expected to further increase in a more modern engine architecture that can achieve increased burn rates in comparison to the CFR engine. NO x emissions from the combustion of anode off-gas were minimal as the cylinder peak temperatures never exceeded 1800 K. This experimental study ultimately demonstrates the viability of an ICE to operate using an anode off-gas, thus creating a complementary role for an ICE to be paired with a SOFC in a hybrid power generation plant.

Engineering↗
DOE OSTI2011

2011 Status of the Automatic Alignment System for the National Ignition Facility

Automated alignment for the National Ignition Facility (NIF) is accomplished using a large-scale parallel control system that directs 192 laser beams along the 300-m optical path. The beams are then focused down to a 50-micron spot in the middle of the target chamber. The entire process is completed in less than 50 minutes. The alignment system commands 9,000 stepping motors for highly accurate adjustment of mirrors and other optics. 41 control loops per beamline perform parallel processing services running on a LINUX cluster to analyze high-resolution images of the beams and their references. This paper describes the status the NIF automatic alignment system and the challenges encountered as NIF development has transitioned from building the laser, to becoming a research project supporting a 24 hour, 7 day laser facility. NIF is now a continuously operated system where performance monitoring is increasingly more critical for operation, maintenance, and commissioning tasks. Equipment wear and the effects of high energy neutrons from fusion experiments are issues which alter alignment efficiency and accuracy. New sensors needing automatic alignment assistance are common. System modifications to improve efficiency and accuracy are prevalent. Handling these evolving alignment and maintenance needs while minimizing the impact on NIF experiment schedule is expected to be an on-going challenge for the planned 30 year operational life of NIF.

42 ENGINEERING↗
DOE OSTI2023

National Ignition Facility Opacity Time Resolved Spectrometer Systems Engineering Final Project

The National Ignition Facility (NIF) is the world’s largest and most energetic laser facility. The NIF system is designed to produce high energy density (temperature and pressure) conditions through the application of its 192 laser beams. One of the users of NIF is the opacity platform developed to study the opacities at temperatures and densities relevant to the solar interior and stellar evolution. The platform was developed to study iron (Fe) opacity at temperatures relevant to the solar interior. The opacity campaign uses spectrometers to gather data. Spectrometers utilize crystals to produce x-ray spectra that are recorded on time-integrated and time-resolved detectors. The opacity spectrometer (OpSpec) currently fielded and in use at NIF uses a time integrated film channel to collect data. The opacity spectrometer time resolved (OpSpecTR) will utilize novel hCMOS detectors to capture time resolved images of spectra of interest. The key stakeholders identified for OpSpecTR included the physicists responsible for OpSpec and OpSpecTR, the Target Area Science and Engineering (TASE) department at NIF, the NIF and Photon Science (NIF & PS) Opacity program, the Nevada National Security Site (NNSS) Physics and Engineering program, the Sandia hCMOS manufacturing and testing program, and the Los Alamos National Laboratory (LANL) program sponsor. The Target and Experimental Operations (TEXOPS) was identified as a key stakeholder because the group includes the individuals that will physically interact with the OpSpecTR system as it participates in NIF experiments. The opacity platform collects data in a unique orientation relative to the existing diagnostics fielded at NIF. The existing infrastructure at NIF uses a diagnostic manipulator (DIM) to insert the diagnostic near the target chamber center to collect data during a NIF shot. Existing diagnostics collect data through the center line of the DIM axis and collect relevant data perpendicular to this axis. The opacity platform requires crystals mounted in a specific orientation which requires data collection parallel to the DIM axis. This deviation from standard NIF practices was a key factor in developing requirements.

42 ENGINEERING↗
NASA NTRSDate not supplied

SLS Ignition Overpressure-Sound Suppression System Performance Evaluated Against Historical Configurations

During the start-up of a number of launch vehicles that include solid rocket motor (SRM), the ignition transient and acoustic environments are mitigated by the implementation of a water spray system located immediately below the SRM nozzle exit plane (NEP). For NASA’s Space Launch System (SLS), this water system is referred to as the Ignition Overpressure / Sound Suppression (IOP/SS) system. The SLS Induced Environments (IE) technical discipline conducted a comprehensive evaluation of the design and as-tested performance of the IOP/SS water that will operate underneath both Boosters during the Artemis I launch. As part of this evaluation, flow rates and imagery from a number of integrated launch pad / mobile launcher IOP/SS flow tests were studied. Additional insight was leveraged from the Shuttle heritage IOP/SS system that includes data and imagery from a number of Flight Readiness Firings (FRF) and water flow tests. Lastly, the IE study included a qualitive comparison of the Shuttle and SLS systems to the equivalent water flow systems for Titan and Atlas V and determined that the NASA water flow systems are substantially different than those supporting other launch vehicles.

Ignition Overpressure↗
NASA NTRSDate not supplied

SLS Ignition Overpressure-Sound Suppression System Performance Evaluated Against Historical Configurations

During the start-up of a number of launch vehicles that include solid rocket motor (SRM), the ignition transient and acoustic environments are mitigated by the implementation of a water spray system located immediately below the SRM nozzle exit plane (NEP). For NASA’s Space Launch System (SLS), this water system is referred to as the Ignition Overpressure / Sound Suppression (IOP/SS) system. The SLS Induced Environments (IE) technical discipline conducted a comprehensive evaluation of the design and as-tested performance of the IOP/SS water that will operate underneath both Boosters during the Artemis I launch. As part of this evaluation, flow rates and imagery from a number of integrated launch pad / mobile launcher IOP/SS flow tests were studied. Additional insight was leveraged from the Shuttle heritage IOP/SS system that includes data and imagery from a number of Flight Readiness Firings (FRF) and water flow tests. Lastly, the IE study included a qualitive comparison of the Shuttle and SLS systems to the equivalent water flow systems for Titan and Atlas V and determined that the NASA water flow systems are substantially different than those supporting other launch vehicles.

Ignition Overpressure↗
DOE OSTI2023

LANL MPCL Measurement System Analysis: AMPTEC 630ES Igniter Tester / Ohmmeter

This comprehensive analysis aimed to evaluate the measurement capability of the AMPTEC 630ES Explosive Safety Igniter Tester, a critical tool for organizations engaged in the measurement of High Explosive components and related Electro-Explosive devices. With a history of notable calibration issues involving specific model numbers, the Metrology Program and Calibration Laboratory (MPCL) initiated an extensive Measurement System Analysis. The analysis's primary focus was to thoroughly quantify the various sources of measurement variability intrinsic to the calibration process. It centered on two pivotal aspects: repeatability (the variation observed when the same operator uses the same instrument) and reproducibility (the variation seen when different operators perform measurements). A secondary objective was to determine whether equipment usage and age had any impact on the instrument's performance.

47 OTHER INSTRUMENTATION↗
DOE OSTI2021

Low Temperature Time-to-Explosion Experiments on HMX in the LLNL's ODTX/P-ODTX System (FY 2020 Annual Report)

Over the last few decades, there has been a considerable research effort on the thermal decomposition and thermal explosion violence of energetic materials at elevated temperatures in different sample geometries and confinements. Thermal explosion studies on various energetic materials in two-dimensional geometry such as the Scaled-Thermal-Explosion-Experiment (STEX) system and the Sandia-Instrumented-Thermal-Ignition (SITI) system have been reported. The One-Dimensional Time to Explosion (ODTX) system, designed and built by LLNL, has been used since 1970s for thermal explosion studies. The system is attractive because of the one-dimensional geometry and minimal sample requirement. With the recent integration of a pressure monitoring element, the system can study pressure behavior of materials subjected to and during thermal exposure. Rapid pressure monitoring in µsec intervals allow for enhanced pressure determination in the time right before thermal explosion. The test data can be used for the validation of existing thermal models, particularly for introducing pressure terms. This report summarizes the efforts in performing small-scale safety tests, particle size measurements and conducting 7 ODTX/P-ODTX experiments on the Cl5 HMX material that Hunting uses for oil field applications.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Aperture design for the third neutron and first gamma-ray imaging systems for the National Ignition Facility

The current construction of a new nuclear-imaging view at the National Ignition Facility will provide a third line of sight for hotspot and cold fuel imaging and the first dedicated line of sight for 4.4-MeV γ-ray imaging of the remaining carbon ablator. To minimize the effort required to hold and align apertures inside the vacuum chamber, the apertures for the two lines of sight will be contained in the same array. We discuss the system requirements for neutron and γ-ray imaging and the resulting aperture array design.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2014

Requirements Document for the Redesign of the DIM-based Diagnostics Transport and Handling System at the National Ignition Facility (NIF)

The National Ignition Facility (NIF, Figure 1) is the world’s leading user research facility for inertial confinement fusion. Diagnostic instruments that collect data from the experiment shots are transported around the facility using a series of disjointed, suboptimal transport and handling (T&H) subsystems that compromise user efficiency and ergonomics. Significant time savings and improvements to the diagnostic exchange process could be realized by designing a new transport and handling system that minimizes the hand-offs between T&H subsystems, reduces operator hassle and ergonomic strain, and improves the long-term maintainability of the system. In contrast to the current system – which employs several manually-operated carts and containers to transport the diagnostic, dock it to its destination, and install it – the new diagnostic transporter integrates the contamination container with the transport cart and provides a dynamic range of adjustability to interface with its destination. This single transporter has the requisite maneuverability, height adjustability, and fine adjustment capabilities without any rigging transactions to support contaminated diagnostic transport and handling at the alignment station and Equatorial and Polar DIMs. A remote-controlled user interface device allows operators a more hands-off experience that reduces ergonomic strain and improves safety. Assuming the cost is not prohibitive, diagnostic storage will be accomplished by simply stowing the transporter in its lowest position in the designated area of NIF. This concept for a new diagnostic transport and handling system would be better aligned with the core values of NIF: safety, quality, and reliability.

42 ENGINEERING↗
DOE OSTI2012

X-ray Streak Camera Cathode Development and Timing Accuracy of the 4w UV Fiducial System at the National Ignition Facility

The convergent ablator experiments at the National Ignition Facility (NIF) are designed to measure the peak velocity and remaining ablator mass of an indirectly driven imploding capsule. Such a measurement can be performed using an x-ray source to backlight the capsule and an x-ray streak camera to record the capsule as it implodes. The ultimate goal of this experiment is to achieve an accuracy of 2% in the velocity measurement, which translates to a {+-}2 ps temporal accuracy over any 300 ps interval for the streak camera. In order to achieve this, a 4-{omega} (263nm) temporal fiducial system has been implemented for the x-ray streak camera at NIF. Aluminum, Titanium, Gold and Silver photocathode materials have been tested. Aluminum showed the highest quantum efficiency, with five times more peak signal counts per fiducial pulse when compared to Gold. The fiducial pulse data was analyzed to determine the centroiding a statistical accuracy for incident laser pulse energies of 1 and 10 nJ, showing an accuracy of {+-}1.6 ps and {+-}0.7 ps respectively.

42 ENGINEERING↗
DOE OSTI2012

X-ray streak camera cathode development and timing accuracy of the 4{omega} ultraviolet fiducial system at the National Ignition Facility

The convergent ablator experiments at the National Ignition Facility (NIF) are designed to measure the peak velocity and remaining ablator mass of an indirectly driven imploding capsule. Such a measurement can be performed using an x-ray source to backlight the capsule and an x-ray streak camera to record the capsule as it implodes. The ultimate goal of this experiment is to achieve an accuracy of 2% in the velocity measurement, which translates to a {+-}2 ps temporal accuracy over any 300 ps interval for the streak camera. In order to achieve this, a 4{omega} (263 nm) temporal fiducial system has been implemented for the x-ray streak camera at NIF. Aluminum, titanium, gold, and silver photocathode materials have been tested. Aluminum showed the highest relative quantum efficiency, with five times more peak signal counts per fiducial pulse when compared to Gold. The fiducial pulse data were analyzed to determine the centroiding statistical accuracy for incident laser pulse energies of 1 and 10 nJ, showing an accuracy of {+-}1.6 ps and {+-}0.7 ps, respectively.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2020

Microwave ignition of energetic material housed within a gun

The systems and methods for microwave ignition of energetic material housed within a gun (e.g., primers and/or propellants) allow for the use of insensitive energetic materials and/or insensitive gas-generating materials in place of sensitive energetic materials relied upon by mechanical ignition systems. In some embodiments, the use of insensitive energetic materials and/or insensitive gas-generating materials increase the safety and reliability of guns that would otherwise need to depend on sensitive energetic material required by mechanical or laser ignition mechanisms. Additionally, in some embodiments, the systems and methods provide greater versatility with respect to the variety of energetic materials that may be employed within guns.

42 ENGINEERING↗