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At least 541 records · Page 30
All sourcesNASA NTRSDOE OSTI
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↗
DOE OSTI2019

TA-16-0303 Crystal Grow Lab Renovation [Slides]

The LANL High Explosives (HE) Crystal Lab at TA-40 Building 12 is a unique, and nearly the sole, national resource for the growth and sample preparation of large HE single crystals and related materials. This work has outgrown is current facility and is in dire need of both additional space and modern lab technology. The goal of this project is to renovate the 1950’s era building TA-16-303 to accommodate these operations and successfully relocate them from TA-40-12. Phase 1 of this project, completed in May of 2018, was to de-energize the facility and perform clean-up / remediation activities. Phase 2, the actual renovation of the facility, is currently underway and on track to achieve Occupancy by May of 2020.

36 MATERIALS SCIENCE↗
DOE OSTI2019

A Section 110 Evaluation of the Project 57 Rad-Safe Area Personnel Decontamination Building, Nye County, Nevada

Project 57 was an open-air, plutonium-dispersal safety test conducted by the United States in 1957 on a portion of the Nevada Test and Training Range (NTTR) (formerly the Las Vegas Bombing and Gunnery Range). The Project 57 test area, once known as Area 13, was a block of land abutting the northeastern boundary of the Nevada Test Site (NTS). The NTS was renamed the Nevada National Security Site (NNSS) in 2010. In keeping with the historical Cold War period designation, NTS will be used when discussing historic period events, while NNSS will be applied for contemporary activities. During Project 57, the high explosives of a nuclear weapon were triggered asymmetrically to simulate an accidental detonation. The test was conducted to study the extent of plutonium contamination from a nonnuclear yield accident, as well as assess the biological and environmental hazards such an event could create. Following the conclusion of the experiment, the contaminated area surrounding the ground zero (GZ) was fenced off and some of the contaminated equipment was buried in place. The Project 57 Rad-Safe area was abandoned. In 1981, the U.S. Department of Energy (DOE) decontaminated and decommissioned the Project 57 site. This Section 110 documentation was prompted by recognition that more than five decades have passed since the abandonment of the Project 57 Rad-Safe area, particularly the personnel decontamination building, which leaves the temporary structure vulnerable to natural forces of weathering and decay. However, these temporary facilities remain partially standing, allowing for a condition assessment and recommendations regarding the Rad-Safe area’s historical significance. The National Nuclear Security Administration, Nevada Field Office (NNSA/NFO) determined there was no area of potential effect (APE) (direct, indirect, or visual) because there is no planned undertaking and the Project 57 Rad-Safe area will continue to remain unused. Instead, a 4.5-acre study area was established to facilitate recording the Project 57 personnel decontamination building and the remaining accessory resources. The study area is bounded on the east by Valley Road and it extends to the east far enough to encompass the former Project 57 Rad-Safe area (Figure A-2). The Section 110 study area is located in the northwest quarter of Section 35, Township 07S Range 54E Mount Diablo Base and Meridian. It is on the 1962 Groom Mine SW USGS 7.5-minute series topographic quadrangle. Desert Research Institute (DRI) surveyed the Section 110 study area, resulting in the recording and evaluation of the Project 57 Rad-Safe area personnel decontamination building and four accessory resources (AR-1 through AR-4). Copies of the building form and report are on file at DRI and with the NNSA/NFO in Las Vegas, Nevada.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

TA-16-0303 Crystal Grow Lab Renovation

The LANL High Explosives (HE) Crystal Lab at TA-40 Building 12 is a unique, and nearly the sole, national resource for the growth and sample preparation of large HE single crystals and related materials. This work has outgrown is current facility and is in dire need of both additional space and modern lab technology. The goal of this project is to renovate the 1950’s era building TA-16-303 to accommodate these operations and successfully relocate them from TA-40-12. Phase 1 of this project, completed in May of 2018, was to de-energize the facility and perform cleanup / remediation activities. Phase 2, the actual renovation of the facility, is currently underway and scheduled to achieve Occupancy by September of 2020.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2020

Site 300 B-851 Permit: Radiological Assumptions and Source Term - Air Dispersion Modeling for Radiological Dose Assessment

The following modeling assumptions and source term that is provided in the attachments to this document are meant to serve as a guide to the presentation delivered on April 23rd, 2020, to the San Joaquin Air District Permit Services slides. This analysis is in response to the District’s “Project Incompleteness Letter” (Facility Number: N-472 and Project Number: N-1173492) regarding the potential for depleted uranium (DU) to be resuspended from areas of contaminated soil at Site 300 as a result of high explosive (HE) experiments increased to a requested permitted maximum of 1,000 pound detonations with an annual HE throughput not to exceed 7,500 pounds per year. LLNL has taken every step in the radiological health risk concerns in the modeling assumptions and final source term to be at a level of maximum conservativeness. As an example, forty soil samples were taken in the B-851 area (LLNL-AR-738708 – 2018) and assayed for uranium-234, uranium-235, and uranium-238 concentrations. The maximum uranium soil concentrations were used in the assumptions (potential for resuspended dust occurring from detonation experiments) and not the use of median uranium soil concentrations – a more realistic outcome. Additionally, these uranium soil concentrations were considered to be at 100% uptake in the vegetation for prescribed burns; vegetation uptake factors were not used as that would lower the final source term. This level of conservativeness was maintained throughout the modeling assumptions.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗