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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.

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At least 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS1983

Advanced Automotive Diesel Assessment Program, executive summary

The objectives of this analytical study were: to select one advanced automotive diesel engine (AAD) concept which would increase the tank mileage of a 3,000 pound passenger car from the present 35 mpg to at least 52 mpg; to identify long term component research and development work required to bring the selected concept to fruition; and to prepare a development strategy that will bring the selected concept to a prototype testing phase. Cummins Engine Company has completed this study. The selected concept is a 4 stroke cycle, direct injection, spark assisted, advanced adiabatic diesel engine with positive displacement compounding plus expander and part load air preheating. The engine does not use a liquid coolant nor liquid lubricants. It is a 4 cylinder, in-line, 77 mm bore x 77 mm stroke, 1.434 liters displacement engine weighing 300 lb, and rated at 70 BHP at 3000 rpm. Installation dimensions are 621 mm length x 589 mm width x 479 mm height (24.4 inch x 22 inch x 18.9 inch).

Source record↗
NASA NTRS2005

Simultaneous quantification of poly-dispersed anionic, amphoteric and nonionic surfactants in simulated wastewater samples using C18 high-performance liquid chromatography-quadrupole ion-trap mass spectrometry

This paper describes the development of a guantitative method for direct and simultaneous determination of three frequently encountered surfactants, amphoteric (cocoamphoacetate, CAA), anionic (sodium laureth sulfate, SLES), and nonionic (alcohol ethoxylate, AE) using a reversed-phase C18 HPLC coupled with an ESI ion-trap mass spectrometer (MS). Chemical composition, ionization characteristics and fragmentation pathways of the surfactants are presented. Positive ESI was effective for all three surfactants in agueous methanol buffered with ammonium acetate. The method enables rapid determinations in small sample volumes containing inorganic salts (up to 3.5 g L(-1)) and multiple classes of surfactants with high specificity by applying surfactant specific tandem mass spectrometric strategies. It has dynamic linear ranges of 2-60, 1.5-40, 0.8-56 mg L(-1) with R2 egual or greater than 0.999, 0.98 and 0.999 (10 microL injection) for CAA, SLES, and AE, respectively.

Chromatography, High Pressure Liquid/methods↗
DOE OSTI2023

Molten Salt Tritium Transport Experiment: A Versatile Fluoride Salt Loop for Validation of Tritium Transport Phenomena

Tritium is generated in Molten Salt Reactors (MSRs) from neutron capture by lithium and other constituents of the molten salt FLiBe. Tritium is a unique radionuclide as it readily permeates through hot structural materials. Thus, any material in contact with tritium laden molten salt is a potential pathway for release. Understanding tritium transport and devising adequate control strategies is necessary for the safe operation of MSRs. The Molten Salt Tritium Transport Experiment (MSTTE) is a forced-convection fluoride salt loop with the capability to inject hydrogen isotopes into flowing molten salt and to measure transport phenomena such as permeation through metals and evolution from free-surfaces. MSTTE is designed to be versatile to test potential control technology in future campaigns. This report focuses on the current design and analysis of MSTTE. Custom designed and fabricated experiment components such as the hydrogen injection system, permeation test section, diagnostics, and gas distribution system are discussed in detail. System-level tritium transport modeling using the System Analysis Module investigates experiment parameters such as hydrogen source terms, salt flow rate, and salt temperature. Computational fluid dynamics of the salt flow in the permeation test section informs design choices to establish fully developed flow in the measured permeation zone.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2023

Assessing reservoir performance for geologic carbon sequestration in offshore saline reservoirs

Carbon capture and storage (CCS) is a technological strategy to reduce CO 2 emissions from hydrocarbon-based energy production and non-energy industrial emitters, like fertilizer and cement production. To expand the geographic opportunities for CCS, offshore geologic settings are increasingly considered for saline CO 2 storage, particularly where legacy oil and gas infrastructure may be repurposed for CO 2 transport and injection. In this context, the Gulf of Mexico (GoM), United States (U.S.), may offer tremendous opportunity for CCS because the surrounding states are among the largest CO 2 producers in the U.S. and there has been extensive oil and gas development over the last half century. Nevertheless, there remains significant uncertainty in how GoM reservoir/seal systems will respond to industrial-scale CO 2 injections, particularly in the context of meso-scale (1–10s of meters) permeability variations that are difficult to identify prior to injection. Such permeability variations can have significant impacts on CO 2 migration and fluid pressure propagation, both of which govern the overall effectiveness of the CCS project. This research uses ensemble simulation methods to quantify the influence of spatially variable and a priori unknown permeability fields on CO 2 plume development and fluid pressure propagation when CO 2 is injected at 1 MMt per year for ten years. Results show a number of characteristic patterns that reveal the substantial influence of both near- and far-field permeability on reservoir performance. By focusing on basin characteristics that are common among offshore basins worldwide, results from this study suggest that offshore CCS may be a feasible carbon management strategy in regions where offshore basins are proximal to industrial CO 2 sources.

42 ENGINEERING↗
DOE OSTI2019

The use of partial fuel stratification to enable stable ultra-lean deflagration-based Spark-Ignition engine operation with controlled end-gas autoignition of gasoline and E85

Lean operation of Spark-Ignition engines can provide higher thermal efficiency compared to standard stoichiometric operation. However, for a homogeneous lean mixture, the associated reduction of flame speeds becomes an important issue from the perspective of robust ignition and fast flame spread throughout the charge. This study is focused on the use of a lean partial fuel stratification strategy that can stabilize the deflagration, while sufficiently fast combustion is ensured via the use of end-gas autoignition. The engine has a spray-guided Direct-Injection Spark-Ignition combustion system and was fueled with either a high-octane certification gasoline or E85. Partial fuel stratification was achieved using several fuel injections during the intake stroke in combination with a small pilot-injection concurrent with the Spark-Ignition. The results reveal that partial fuel stratification enables very stable combustion, offering higher thermal efficiency for parts of the load range in comparison to well-mixed lean and stoichiometric combustion. The heat release and flame imaging demonstrate that the combustion often has three distinct stages. The combustion of the pilot-injected fuel, ignited by the normal spark, acts as a “super igniter,” ensuring a very repeatable initiation of combustion, and flame incandescence reveals locally rich conditions. The second stage is mainly composed of blue flame propagation in a well-mixed lean mixture. The third stage is the compression autoignition of a well-mixed and typically very lean end-gas. The end-gas autoignition is critical for achieving high combustion efficiency, high thermal efficiency, and stable combustion. Partial fuel stratification enables very effective combustion-phasing control, which is critical for controlling the occurrence and intensity of end-gas autoignition. Comparing the gasoline and E85 fuels, it is noted that achieving end-gas autoignition for the higher octane E85 requires a more aggressive compression of the end-gas via the use of a more advanced combustion phasing or higher intake-air temperature.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2022

Light-Dependence of Formate (C1) and Acetate (C2) Transport and Oxidation in Poplar Trees

Although apparent light inhibition of leaf day respiration is a widespread reported phenomenon, the mechanisms involved, including utilization of alternate respiratory pathways and substrates and light inhibition of TCA cycle enzymes are under active investigation. Recently, acetate fermentation was highlighted as a key drought survival strategy mediated through protein acetylation and jasmonate signaling. Here, we evaluate the light-dependence of acetate transport and assimilation in Populus trichocarpa trees using the dynamic xylem solution injection (DXSI) method developed here for continuous studies of C1 and C2 organic acid transport and light-dependent metabolism. Over 7 days, 1.0 L of [13C]formate and [13C2]acetate solutions were delivered to the stem base of 2-year old potted poplar trees, while continuous diurnal observations were made in the canopy of CO2, H2O, and isoprene gas exchange together with δ13CO2. Stem base injection of 10 mM [13C2]acetate induced an overall pattern of canopy branch headspace 13CO2 enrichment (δ13CO2 +27‰) with a diurnal structure in δ13CO2 reaching a mid-day minimum followed by a maximum shortly after darkening where δ13CO2 values rapidly increased up to +12‰. In contrast, 50 mM injections of [13C]formate were required to reach similar δ13CO2 enrichment levels in the canopy with δ13CO2 following diurnal patterns of transpiration. Illuminated leaves of detached poplar branches pretreated with 10 mM [13C2]acetate showed lower δ13CO2 (+20‰) compared to leaves treated with 10 mM [13C]formate (+320‰), the opposite pattern observed at the whole plant scale. Following dark/light cycles at the leaf-scale, rapid, strong, and reversible enhancements in headspace δ13CO2 by up to +60‰ were observed in [13C2]acetate-treated leaves which showed enhanced dihydrojasmonic acid and TCA cycle intermediate concentrations. The results are consistent with acetate in the transpiration stream as an effective activator of the jasmonate signaling pathway and respiratory substrate. The shorter lifetime of formate relative to acetate in the transpiration stream suggests rapid formate oxidation to CO2 during transport to the canopy. In contrast, acetate is efficiently transported to the canopy where an increased allocation towards mitochondrial dark respiration occurs at night. The results highlight the potential for an effective integration of acetate into glyoxylate and TCA cycles and the light-inhibition of citrate synthase as a potential regulatory mechanism controlling the diurnal allocation of acetate between anabolic and catabolic processes.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2026

Cosmic axions revealed via amplified modulation of the ellipticity of a laser

We propose a new axion dark matter detection strategy that employs optical readout of laser beam ellipticity modulations caused by axion-induced electric fields in a microwave cavity, using electro-optic (EO) crystals, enhanced by externally injected radio-frequency (rf) power. Building upon the variance-based probing method [Phys. Rev. D 107, 103005 (2023).], we extend this concept to the optical domain: A weak probe laser interacts with an EO crystal coupled to the resonant microwave cavity field at cryogenic temperatures, and the axion-induced electric field is revealed through induced ellipticity. The injected rf signal coherently interferes with that of the axion field, amplifying the optical response and significantly improving sensitivity. While our EO-based method employs a Fabry-Pérot resonator, we do not require Michelson interferometers. Our method, hence, enables compact, high-frequency axion searches, across the 0.5–50 GHz range. Operating at cryogenic temperatures not only suppresses thermal backgrounds, but, critically, allows the probing method to mitigate the quantum noise. This approach offers a scalable path forward for axion detection over the ∼(few−200) μ⁢eV mass range—covering the preferred parameter space for the postinflationary Peccei-Quinn axion dark matter—using compact, tunable systems.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2022

History Matching and Prediction of a Polymer Flood Pilot in Heavy Oil Reservoir on Alaska North Slope

The first-ever polymer flood pilot to enhance heavy oil recovery on Alaska North Slope is ongoing. After more than 3 years of polymer injection, significant benefit has been observed from the decrease in water cut from 65% to less than 15% in the project producers. The primary objective of this study is to develop a robust history-matched reservoir simulation model capable of predicting future polymer flood performance. In this work, the reservoir simulation model has been developed based on the geological model and available reservoir and fluid data. In particular, four high transmissibility strips were introduced to connect the injector-producer well pairs, simulating short-circuiting flow behavior that can be explained by viscous fingering and reproducing the water cut history. The strip transmissibilities were manually tuned to improve the history matching results during the waterflooding and polymer flooding periods, respectively. It has been found that higher strip transmissibilities match the sharp water cut increase very well in the waterflooding period. Then the strip transmissibilities need to be reduced with time to match the significant water cut reduction. The viscous fingering effect in the reservoir during waterflooding and the restoration of injection conformance during polymer flooding have been effectively represented. Based on the validated simulation model, numerical simulation tests have been conducted to investigate the oil recovery performance under different development strategies, with consideration for sensitivity to polymer parameter uncertainties. The oil recovery factor with polymer flooding can reach about 39% in 30 years, twice as much as forecasted with continued waterflooding. Besides, the updated reservoir model has been successfully employed to forecast polymer utilization, a valuable parameter to evaluate the pilot test’s economic efficiency. All the investigated development strategies indicate polymer utilization lower than 3.5 lbs/bbl in 30 years, which is less than that of the same polymer used in a polymer pilot in Argentina.

Wang, Xindan↗
DOE OSTI2024

Reusable Verification Components for High-Energy Physics readout ASICs

Verification is a critical aspect of designing front-end (FE) readout ASICs for High-Energy Physics (HEP) experiments. These ASICs share several similar functional features, resulting in similar verification objectives, which can be addressed using comparable verification strategies. This contribution presents a set of re-usable verification components for addressing common verification tasks, such as clock generation, reset handling, configuration, as well as hit and fault injections. The components were developed as part of the CHIPS initiative and they have been successfully used in the verification of multiple HEP ASICs.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS2015

Investigation of Gas Seeding for Planar Laser-Induced Fluorescence in Hypersonic Boundary Layers

Numerical simulations of the gas-seeding strategies required for planar laser-induced fluorescence in a Mach 10 (approximately Mach 8.2 postshock) airflow were performed. The work was performed to understand and quantify the adverse effects associated with gas seeding and to assess various types of seed gas that could potentially be used in future experiments. In prior experiments, NO and NO2 were injected through a slot near the leading edge of a flatplate wedge model used in NASA Langley Research Center's 31 in. Mach 10 air tunnel facility. In this paper, nitric oxide, krypton, and iodine gases were simulated at various injection rates. Simulations showing the deflection of the velocity boundary layer for each of the cases are presented. Streamwise distributions of velocity and concentration boundary-layer thicknesses, as well as vertical distributions of velocity, temperature, and mass distributions, are presented for each of the cases. A comparison between simulated streamwise velocity profiles and experimentally obtained molecular tagging velocimetry profiles using a nitric oxide seeding strategy is performed to verify the influence of such a strategy on the boundary layer. The relative merits of the different seeding strategies are discussed. The results from a custom solver based on OpenFOAM version 2.2.1 are compared against results obtained from ANSYS® Fluent version 6.3.

Arisman, C. J.↗
DOE OSTI2023

Assessing the vulnerability of solar inverters to EMPs: Port testing, PCI modeling, and protection strategies

Renewable energy sources are becoming an ever-larger contributor to the power grid. These renewable energy sources depend upon the power electronic devices, specifically inverters, being essential for connecting Photovoltaic (PV) generation to the grid. However, the Electromagnetic Pulses (EMPs) caused by the high-altitude nuclear explosions can generate fast broad-band pulses with nanosecond rise time, potentially causing damage or destruction to electronic components. To assess the vulnerability of PV inverters to high-altitude EMPs, the port testing and Pulsed Current Injection (PCI) modeling schemes are proposed based on the port impedance analysis. Wide-band frequency measurements are achieved by fusing impedance results from three vector network analyzers. Then, a PCI model is used to simulate the induced response to EMP, with two typical immunity levels of EC5 and EC8 tested. Here, the experiment successfully excites the induced voltage and current under EMP, where the voltage and current can reach 1500V/40A and 8000V/150Aunder EC5 andEC8, respectively. The port vulnerability analysis results demonstrate that only some ports can survive under EC5. To defend against the impact of EMP, three protection strategies are discussed.

42 ENGINEERING↗
NASA NTRS2010

Evaluation of Dual-Launch Lunar Architectures Using the Mission Assessment Post Processor

The National Aeronautics and Space Administrations (NASA) Constellation Program is currently designing a new transportation system to replace the Space Shuttle, support human missions to both the International Space Station (ISS) and the Moon, and enable the eventual establishment of an outpost on the lunar surface. The present Constellation architecture is designed to meet nominal capability requirements and provide flexibility sufficient for handling a host of contingency scenarios including (but not limited to) launch delays at the Earth. This report summarizes a body of work performed in support of the Review of U.S. Human Space Flight Committee. It analyzes three lunar orbit rendezvous dual-launch architecture options which incorporate differing methodologies for mitigating the effects of launch delays at the Earth. NASA employed the recently-developed Mission Assessment Post Processor (MAPP) tool to quickly evaluate vehicle performance requirements for several candidate approaches for conducting human missions to the Moon. The MAPP tool enabled analysis of Earth perturbation effects and Earth-Moon geometry effects on the integrated vehicle performance as it varies over the 18.6-year lunar nodal cycle. Results are provided summarizing best-case and worst-case vehicle propellant requirements for each architecture option. Additionally, the associated vehicle payload mass requirements at launch are compared between each architecture and against those of the Constellation Program. The current Constellation Program architecture assumes that the Altair lunar lander and Earth Departure Stage (EDS) vehicles are launched on a heavy lift launch vehicle. The Orion Crew Exploration Vehicle (CEV) is separately launched on a smaller man-rated vehicle. This strategy relaxes man-rating requirements for the heavy lift launch vehicle and has the potential to significantly reduce the cost of the overall architecture over the operational lifetime of the program. The crew launch occurs first, four days prior to the optimal trans-lunar injection (TLI) departure window. This is done to allow for launch delays in the Altair/EDS launch. During this time, the Orion vehicle is required to conduct orbit maintenance while loitering in low Earth orbit (LEO). The alternative architectures presented aim to eliminate the need for costly orbit maintenance maneuvers while loitering in LEO. In all of the alternative architectures considered, it is assumed that the Altair and Orion vehicles are nominally launched 90 minutes apart, depart the Earth separately, and complete the rendezvous and docking sequence at the Moon. In this lunar orbit rendezvous (LOR) strategy, both the Altair and Orion vehicles will require separate EDS stages, and each will be required to perform lunar orbit insertion (LOI). This has the effect of balancing payload requirements between the two launch vehicles at the Earth. In this case, the overall payload mass is increased slightly, but the increased mission costs could potentially be offset by requiring the construction of two rockets similar in size and nature, unlike the current Constellation architecture. Three dual-launch architecture options with LOR were evaluated, which incorporate differing methodologies for mitigating the effects of launch delays at the Earth. Benefits and drawbacks of each of the dual-launch architecture options with LOR are discussed and the overall mission performance is compared with that of the existing Constellation Program lunar architecture.

Stewart, Shaun M.↗
DOE OSTI2025

TCCSP Task 6 Risk Assessment Report

For this Risk Assessment Plan, TCCSP has conducted a site-based risk assessment that quantifies the risk of CO 2 and/or brine leakage as a result of CO 2 injection at TCCSP. The risk assessment covers project planning, construction, injection, post-injection periods and closure of TCCSP. Key technical and non-technical Project risks are identified as part of the Risk Workshop and include a thorough evaluation of related scenarios. Mitigation strategies for the identified risk scenarios are defined to develop a scientifically sound, and community acceptable CO 2 storage Project.

58 GEOSCIENCES↗
NASA NTRS1994

High Earth orbit design for lunar assisted small Explorer class missions

Small Expendable launch vehicles are capable of injecting modest payloads into high Earth orbits having apogee near the lunar distance. However, lunar and solar perturbations can quickly lower perigee and cause premature reentry. Costly perigee raising maneuvers by the spacecraft are required to maintain the orbit. In addition, the range of inclinations achievable is limited to those of launch sites unless costly spacecraft maneuvers are performed. This study investigates the use of a lunar swingby in a near-Hohmann transfer trajectory to raise perigee into the 8 to 25 solar radius range and reach a wide variety of inclinations without spacecraft maneuvers. It is found that extremely stable orbits can be obtained if the postencounter spacecraft orbital period is one-half of a lunar sidereal revolution and the Earth-vehicle-Moon geometry is within a specified range. Criteria for achieving stable orbits with various perigee heights and ecliptic inclinations are developed, and the sensitivity of the resulting mission orbits to transfer trajectory injection (TTI) errors is examined. It is shown that carefully designed orbits yield lifetimes of several years, with excellent ground station coverage characteristics and minimal eclipses. A phasing loop error correction strategy is considered with the spacecraft propulsion system delta V demand for TTI error correction and a postlunar encounter apogee trim maneuver typically in the 30 to 120 meters per second range.

Mathews, M.↗
NASA NTRS2013

Magnetic Field Dependence of the Critical Current in S-N Bilayer Thin Films

Here we investigate the effects a non-uniform applied magnetic field has on superconducting transition-edge sensors (TESs) critical current. This has implications on TES optimization. It has been shown that TESs resistive transition can be altered by magnetic fields. We have observed critical current rectification effects and explained these effects in terms of a magnetic self-field arising from asymmetric current injection into the sensor. Our TES physical model shows that this magnetic self-field can result in significantly degraded or improved TES performance. In order for this magnetically tuned TES strategy to reach its full potential we are investigating the effect a non-uniform applied magnetic field has on the critical current.

Field Dependence↗
DOE OSTI2020

Analysis of Hydrology and Interim Measure Performance in the Chromium Plume at Los Alamos National Laboratory - 20498

Hexavalent chromium, Cr(VI), is present in the regional aquifer beneath Los Alamos National Laboratory (LANL) at concentrations greater than the New Mexico groundwater standard (50 ppb). The source of the Cr is blowdown from a power plant where potassium dichromate was used as a corrosion inhibitor from 1956 to 1972. Blowdown comingled with effluent from another source and migrated approximately 3 miles down a canyon, primarily as surface flow, until reaching an alluvial infiltration zone. The infiltrating water moved vertically through a thick (approximately 900 ft), complex stratigraphic sequence of unsaturated tuffs, basalt, and unconsolidated alluvial deposits. Horizontal transport also took place within spatially limited perched groundwater horizons in the vadose zone (VZ). Breakthrough at the regional aquifer water table is thought to have occurred in multiple hydraulic windows or 'drip points' located approximately 3 miles from the initial release site at the power plant. The regional aquifer is highly heterogeneous and anisotropic, and displays unconfined behavior in an upper zone and confined behavior at depth. The Cr(VI) contamination has so far remained confined to the upper approximately 25 m of the aquifer. The ambient hydraulic gradient in the regional aquifer is toward the east/southeast, but the water table is extremely flat in the Cr plume area compared to surrounding areas. There is some local variability in flow direction, potentially related to effects of seasonal pumping from nearby Los Alamos county water-supply wells, which draw from the regional aquifer several hundred feet below the water table. An interim measure (IM) is currently operating at the site to achieve hydraulic control of plume migration using a series of extraction wells, ion-exchange treatment, and injection along the downgradient portion of the plume. The migration of Cr contamination in the aquifer has been previously evaluated using a calibrated probabilistic numerical model, which has also been used to design the spatial configuration of extraction and injection wells for the IM, and to identify locations for monitoring wells. The model is built using the Finite Element Heat and Mass (FEHM) transfer code, and the Model Analysis and Decision Support (MADS) software is used for analyses. To date, the portion of the IM system that has operated in a continuous manner has been very effective at hydraulic control. Modifications to the flow field associated with the influence of IM pumping and injection are evaluated here, with modeling constraints to be provided by recent observations of tracers injected into both monitoring wells and IM injection wells, as well as opportunistic observations of geochemical signatures of treated ion-exchange effluent injected into IM injection wells. The tracer and geochemical data provide insights into modified flow directions within the Cr plume area that cannot be otherwise obtained. Results of the modeling work are being used to inform adaptive management of IM operations and will be a valuable tool for development and refinement of long-term remediation strategies. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2024

Space charge dominated momentum spread and compensation strategies in the post-linac section of Proton Improvement Plan-II at Fermilab

The upcoming Proton Improvement Plan-II (PIP-II), designated for enhancements to the Fermilab accelerator complex, features a new 800 MeV superconducting linac and a Beam Transfer Line (BTL) to transport the beam to the existing Booster synchrotron. To mitigate the space charge tune shift associated with a high intensity accumulated beam, the low emittance linac beam is used to paint the ring phase space both transversely and longitudinally. To prevent losses caused by particles injected outside the rf separatrix while painting longitudinal phase space, the momentum spread of the incoming beam should not exceed 2.1 x 10^-4. Detailed simulations showed that due to space charge, the rms momentum spread increases to 4 x 10^-4 while it is transported in the BTL --about twice the allowable limit. In this paper, we outline a mitigation strategy involving a debuncher cavity. We discuss location, operating frequency, and gap voltage under both nominal and perturbed beam conditions, specifically accounting for momentum jitter. The impact of cavity misalignments is also assessed. The paper concludes by recommending an optimized configuration.

43 PARTICLE ACCELERATORS↗
DOE OSTI2022

Burning plasma achieved in inertial fusion

The achievement of obtaining a burning plasma is a critical step toward self-sustaining fusion energy. A burning plasma is a fusion plasma where the alpha-particles created by the deuterium-tritium (DT) fusion reactions are the primary source of heating in the plasma, which is necessary to sustain and propagate the fusion reaction to enable high energy gain. After decades of fusion research, a burning plasma state has finally been achieved. Herein, we report upon the first burning-plasma experiments; this state was achieved using a strategy to increase the capsule spatial scale via two different implosion concepts, on the US National Ignition Facility. These experiments show energies from self-heating in excess of the mechanical work injected into the implosions satisfying several burning plasma metrics, the last experiment additionally shows that the fusion self-heating is greater than losses from radiation and heat conduction. These experiments triple the fusion yield performance and show significantly higher yield amplification from self-heating than prior results; remaining degradations can be reduced for even higher fusion performance.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗