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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 595 records · Page 33
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

LAFD: TA-16 HE Facility Familiarization Tour, OJT 55258

Los Alamos National Laboratory (LANL) will conduct familiarization tours for personnel of the Los Alamos County Fire Department (LAFD) at TA-16 high explosives (HE) facilities. These familiarization tours are official LANL business; the purpose of these tours is to orient LAFD firefighters to the facility so that they can respond efficiently and quickly to a variety of emergency situations. This orientation includes, among other topics, ingress and egress of the area and buildings, layout and organization of the facility, evacuation procedures and assembly points, and areas of concern within the various buildings at the facility. LAFD firefighters have the skills and abilities to perform firefighting operations and other emergency response tasks that cannot be provided by LANL personnel who have the required clearance. This handout provides details of the information, along with maps and diagrams, to be presented during the familiarization tours. The handout will be distributed to the trainees at the time of the tour. A corresponding checklist will also be used as guidance during the familiarization tours to ensure that all required information is presented to LAFD personnel.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2017

FINAL DESIGN REVIEW REPORT Subcritical Experiments Gen 2, 3-ft Confinement Vessel Weldment

A Final Design Review (FDR) of the Subcritical Experiments (SCE) Gen 2, 3-ft. Confinement Vessel Weldment was held at Los Alamos National Laboratory (LANL) on September 14, 2017. The review was a focused review on changes only to the confinement vessel weldment (versus a system design review). The changes resulted from lessons-learned in fabricating and inspecting the current set of confinement vessels used for the SCE Program. The baseline 3-ft. confinement vessel weldment design has successfully been used (to date) for three (3) high explosive (HE) over-tests, two (2) fragment tests, and five (5) integral HE experiments. The design team applied lessons learned from fabrication and inspection of these vessel weldments to enhance fit-up, weldability, inspection, and fitness for service evaluations. The review team consisted of five (5) independent subject matter experts with engineering design, analysis, testing, fabrication, and inspection experience. The

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2017

Theory, Solution Methods, and Implementation of the HERMES Model

The HERMES (high explosive response to mechanical stimulus) model was developed over the past decade to enable computer simulation of the mechanical and subsequent energetic response of explosives and propellants to mechanical insults such as impacts, perforations, drops, and falls. The model is embedded in computer simulation programs that solve the non-linear, large deformation equations of compressible solid and fluid flow in space and time. It is implemented as a user-defined model, which returns the updated stress tensor and composition that result from the simulation supplied strain tensor change. Although it is multi-phase, in that gas and solid species are present, it is single-velocity, in that the gas does not flow through the porous solid. More than 70 time-dependent variables are made available for additional analyses and plotting. The model encompasses a broad range of possible responses: mechanical damage with no energetic response, and a continuous spectrum of degrees of violence including delayed and prompt detonation. This paper describes the basic workings of the model.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Developing Lathing Parameters for PBX 9501

This thesis presents the work performed on lathing PBX 9501 to gather and analyze cutting force and temperature data during the machining process. This data will be used to decrease federal-regulation-constrained machining time of the high explosive PBX 9501. The effects of machining parameters depth of cut, surface feet per minute, and inches per revolution on cutting force and cutting interface were evaluated. Cutting tools of tip radius 0.005 -inches and 0.05 -inches were tested to determine what effect the tool shape had on the machining process as well. A consistently repeatable relationship of temperature to changing depth of cut and surface feet per minute is found, while only a weak dependence was found to changing inches per revolution. Results also show the relation of cutting force to depth of cut and inches per revolution, while weak dependence on SFM is found. Conclusions suggest rapid, shallow cuts optimize machining time for a billet of PBX 9501, while minimizing temperature increase and cutting force.

42 ENGINEERING↗
DOE OSTI2018

Investigation of Parameters on Thermally Cycled EBW Detonators

Working towards an optimal exploding bridge wire (EBW) detonator design, three parameters were varied among two detonator platforms. These three parameters were bridge wire diameter, high explosive (HE) density, and sleeve material. These parameters were chosen due to their potential to benefit initiation characteristics. The performance of each parameter was characterized at pristine conditions and after thermal cycling and firing cold. The overall performance as well as the severity of performance loss observed after thermal conditioning were considered. The results of this parameter study are presented and trends related to parameter variation are examined.

42 ENGINEERING↗
DOE OSTI2017

Site 300 HE Shot Results

The results of the high-explosive (HE) blast tests conducted at and near site 300 on the morning of 29 August 1996 are discussed. The RE weights ranged from 30 to 300 lbs.. detonated at Bunkers 801, 850. 851, SRI and P1. The measured peak atmospheric overpressures show that in general the 300 lb. shots produced greater pressure levels than those of 30 lb. shots. In these shots, the peak values usually were below 100 db. near Site 300, including the rcposed development area, and below 110 db. in the Tracy area. However, different overpressure levels may prevail in this area under other circumstances such as weather, since the weather conditions (notably the variations of the temperature and wind vector with altitude) strongly influence the propagation behavior of the blast—induced atmospheric waves.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2017

Blast-Wave Characteristics Near Site 300

We have developed a procedure for calculating the maximum high-explosive weight limit for use at Site 300 based on the analysis of the blast-wave propagation behavior in the atmosphere. Both analytical and experimental efforts have been involved in the present work, including a literature search, evaluation of other data, measurements of local weather conditions, and implementation of relevant computational programs. Major results of the present effort are • Comparison of the LLNL data with other data reveals discrepancies, suggesting that local effects, such as weather conditions in the downrange regions, may play a role in affecting the wave-propagation behavior. Our measurements of the local weather conditions indeed show that they differ from those at Site 300. • Analyses of other, newer models and data have resulted in the implementation of relevant computer codes, such as the BLASTO code, to be used at Site 300. • A new procedure for predicting the weight limit at Site 300 has been recommended. This new procedure consists of - Site 300 and local valley weather measurements. - The LAP code. - The BLASTO code. The LAP code is a modified SIPS code and computes the acoustic ray trajectories, including the focus ("caustic") locations, under varying local weather conditions. The BLASTO code calculates the peak overpressure vs distance relationship for a given charge weight and weather condition. Both the LAP code and the BLASTO code have been implemented and are operational at Site 300. Future plans include conducting selective tests to verify the validity of the predictive procedure recommended for Site 300.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2018

Laser-Driven Megavolt X-Ray and Neutron Source Optimization

This 4-month feasibility study assessed the options, trade-offs and major issues in using National Ignition Facility (NIF) and Advanced Radiographic Capability (ARC)-class laser beams for multipulse MeV x-ray and neutron radiography of high explosives (HE) driven experiments. It was performed in close collaboration with a second FS evaluating future HE radiography requirements and expected laser-based source data quality with respect to existing and alternate radiography sources. The study first reviewed the existing published data on MeV x-ray and neutron sources compared to requirements on yield (10 14 /sr for X-rays, > 10 13 /sr for neutrons), spot size (< 1 mm) and duration (< 20 ns). For MeV neutron sources, the preferred options are DTfilled exploding pusher targets or stagnating DT plasmas, each source requiring 50 kJ level. few ns beam irradiation at 0.5 or 0.35 micron wavelength. The preferred X-ray MeV source option to be fully assessed by a follow-up SI is an angularly and temporally-multiplexed multi-burst version of a Bremsstrahlung source (Courtois et al. 2011) irradiated by up to 7 10 ps, kJ-class 1 micron wavelength lasers beams. This multi-burst laser mode, submitted as an ROI and patent, should increase final laser optics damage energy thresholds based on 2 pulse tests and hence allow near full extraction of the 15 kJ of 1 micron laser energy available on a NIF beamline. Hydrodynamic simulations were used to evaluate the effects of preceding pulse irradiation on target integrity, and show that this can be mitigated by using 3D structured targets.

47 OTHER INSTRUMENTATION↗
DOE OSTI2018

FY18 J23X PDZG Final Report: Double Shock Initiation of PBX 9502 Lot HOL88H891-008

Heterogeneous high explosives subjected to sub-critical shock waves are known to exhibit desensitization to later shock inputs. While it is believed that this phenomenon is due to the removal of hot spot forming features in the explosive by the initial sub-critical shock, the effect of the time delay between the shocks is poorly understood. This report details a series of double shock plate impact experiments that vary the time between similar shocks to explore the time dependance of this shock desensitization process. These experiments were performed on the insensitive explosive PBX 9502 (95% TATB, 5% Kel-F 800) with lot number HOL88H891-008. The evolution of the shocks to a detonation was characterized by 9 embedded magnetic particle velocity gauges, and 116 embedded magnetic time of arrival gauges (AKA shock trackers). Photon Doppler velocimetry (PDV) with a LiF window was used at the back surface of the samples to capture the wave profile exiting the sample. Three double shock experiments were performed, with first and second shock pressures of 8.3 GPa and 16.5 GPa, respectively. An analogous single shock experiment at 16.3 GPa was also performed. The double shock experiments exhibited small levels of reaction during the initial shock,and shock desensitization to the second shock. Run distances after shock coalescence were shorter than those expected for a single shock, indicating the shock to detonation transition (SDT) process was slightly further along due to partial reaction in the first shock wave. These data will be used to calibrate model behavior under multiple-shock conditions. Additional double shock data will be collected to further explore this area in FY2019. All data have been uploaded to the LANL Small Scale Database for use by the research community.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2018

Review of PBX 9502 Pop Plot data

Pop plot data (distance of run and time to detonation as a function of shock pressure) is a simple characterization of shock initiation of a high explosive. It is used, along with other data, to calibrate reactive burn models. For the insensitive TATB based explosive PBX 9502, there are data at 5 initial temperatures (77 K, -55 C, 23 C, 76 C, 130 C) and for several lots. Here we review the dependence of the Pop plot on temperature and the variation with lot. There is a significant increase in shock sensitivity with temperature.Since the Pop plot is important for modeling, fit parameters are interpolated to cover the temperature range –55 < T < 76 C. The scatter in the data and variation with lot is important for assessing the accuracy to which a model can be calibrated.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2018

Transmittal of Draft Consultation Letter to the New Mexico State Historic Preservation Officer Regarding the Proposed Loading Dock to Conference Room Conversion Building 303 at Technical Area 16

The U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA), Los Alamos Field Office (NA-LA) proposes to enclose the existing loading dock to create a conference room at building 303, located within Technical Area (TA) 16, Los Alamos National Laboratory (LANL). TA-16-303 has been determined eligible for listing in the National Register of Historic Places in correspondence with the New Mexico State Historic Preservation Division dated June 22, 2003. Eligibility status is based on its historical significance during the Cold War at Los Alamos and its representative architectural style, which is associated with high explosives research and development in support of the nation’s nuclear weapons program. As shown in the enclosed photograph, key architectural elements include a flat roof with overhangs, unpainted reinforced-concrete construction, green painted doors and trim.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2019

Reevaluation of Three Cold War-Era Buildings at Technical Area 22

The U.S. Department of Energy, National Nuclear Security Administration, Los Alamos Field Office (Field Office) reevaluated three magazines (buildings 7, 8, and 10) at Technical Area (TA) 22, Los Alamos National Laboratory (LANL or the Laboratory) (Map 1). This reevaluation was conducted because the magazines have been identified as candidates for preservation due to their association with the almost 40 years of Cold War-era detonator research conducted at adjacent building TA-22-1 (Maps 2–4), a property that is eligible for inclusion in the Manhattan Project National Historical Park (MAPR) for its role in the assembly of the wartime Fat Man bomb. Cold War-era magazines, TA-22-7, -8, and -10, were originally determined not eligible for listing in the National Register of Historic Places (Register) in DX Division’s Facility Strategic Plan: Consolidation and Revitalization at Technical Areas 6, 8, 9, 14, 15, 22, 36, 39, 40, 60, and 69 (McGehee et al. 2005) in consultation with the State Historic Preservation Officer on April 18, 2006. Many of the magazines at TA-22 are of identical construction, and at the time of the initial evaluation, other magazines were selected as the best examples of type for the purpose of architectural documentation. The reevaluation is being conducted because the status of TA-22-1 and its immediate area have changed since the MAPR was authorized in December 2014. The three magazines, along with a magazine that was previously determined eligible in 2006 (TA-22- 9), are within one of the proposed boundaries for the MAPR at LANL and are also now considered candidates for preservation. These magazines were constructed in 1949 to support detonator research, development, and testing, and have served as reinforced storage facilities for high explosives since their construction.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2019

Proof Testing of Small-Scale HE Press Shielding

High explosives pressing activities at Los Alamos National Laboratory have played a critical role in meeting the core missions of the lab since its early days. Small scale pressing (25 grams of energetic material or less) constitutes a significant portion of current production and much of this occurs as an attended operation. Workers that are present during HE pressing operations are to be protected from blast and fragment dangers associated with the potential violent reaction of the energetic material being pressed. Safety is paramount in all HE operations, and the ongoing evolution of analysis and mitigation of hazards contributes strongly to the development of adequate protections for personnel. Attended pressing operations satisfying Class 1 Level Protection criteria, until recently, have been allowed for small scale pressing activities on the basis of an undocumented design of shielding enclosures used at LANL. Recent review of the shield design has determined the necessity of proof testing an adequate enclosure and thoroughly documenting the test results and fabrication specifications. This will provide a basis for continuing attended operations and guidance for future design iterations. The results of the testing described in this report provide sufficient assurance that the new shield design is adequate to protect attendant workers against injury from direct blast and fragments resulting from full detonation of the maximum allowable mass of explosives (less than 25 grams) confined in a uniaxial pressing configuration typical for Los Alamos National Laboratory.

42 ENGINEERING↗
DOE OSTI2019

Remote Sensing of Dynamic Events [Slides]

Research into using advanced methods for remote sensing applications. A particular interest is in remote sensing of dynamic events involving high explosives (HE) and estimating parameters (e.g., temperature) that characterize the fireball. However, the research is interested in machine learning (ML) for infrared remote sensing in general. The motivation is to improve remote sensing methods of dynamic events to help with validation of computational physics codes.

47 OTHER INSTRUMENTATION↗
DOE OSTI2019

Equations of State with Magpie [Slides]

Magpie is a thermochemical equilibrium code developed at LANL. It calculates equations of state for high explosive (HE) mixtures quickly using statistical mechanics.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Approach of a planar detonation to a steady CJ detonation wave

Generating a planar steady detonation wave in a high explosive is important for accurately measuring key parameters such as the CJ detonation state and the reaction-zone width. A detonation wave can be promptly shock initiated in the TATB based explosive PBX 9502 due to a fast hotspot reaction. However, a slow carbon clustering reaction causes the detonation wave to have a slow approach to steady state. Here we study the approach of the reaction zone of a planar detonation to the steady ZND profile of an underdriven detonation wave. For PBX 9502 simulations were run with the SURFplus reactive burn model. For comparison, simulations were also run with the HMX based PBX 9501. The SURF reactive model is used for PBX 9501 since it has only a fast hotspot reaction.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2019

Thermal and Mechanical Characterization of DAAF and LAX-133 (FY19 Summary Report)

We have performed a series of thermal and mechanical tests to characterize the high explosive 3,3’-diamino-4,4’-azofurazan (DAAF), as well as the formulated version LAX-133 (97 wt% DAAF and 3 wt% FK-800 binder, now also referred to as PBX 9701; for clarity in this report, we will use the name LAX-133 which is what the formulated material was called at the time this work was performed). Specifically, we have used axially die-pressed cylinders (with no further machining) of neat DAAF and of LAX-133 to make measurements of compressive strength, Brazil disk, coefficient of thermal expansion (CTE), as well as irreversible volume expansion with thermal cycling (ratchet growth).

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2019

Reverse Initiation of the Reynolds RP-87 Detonator Resulting from Off-Normal Functioning of the Ultrafast Closure Valve System

A series of tests were executed to ensure complete UCV high explosive material consumption in the case of a system anomaly occurring — specifically a firing event where one or more RP-87 detonators do not function as a result of an arming and firing system problem or some other circumstance where a detonator does not function even though a firing signal is received at the bridgewire. A simplified linear array was utilized with 5 detonators per test firing only one detonator and maintaining the critical as-designed UCV dimensions and HE mass-to-volume ratios which can affect sympathetic initiation behavior. Tests were performed using both KTech Corporation's stated detonator gap of 0.060" as well as larger gaps to determine safety margin. The detonator's explosive contents were completely consumed in all cases where the gap was maintained within stated specifications. Only extreme gap conditions (0.30") indicated remaining explosive material. The mechanism by which the material is reacted does change with increasing gap however, transferring to a deflagration at larger gaps. All tests were performed at SNL/NM site 9930 in April 2013.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗