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The purpose of this CR is to provide a summary of the completed closure activities, documentation of waste disposal, and analytical data to confirm that the remediation goals were met.
The Versatile Test Reactor (VTR) is a sodium-cooled, fast-spectrum test reactor that is being developed in the United States and will support a variety of irradiation test vehicle configurations, including cartridge loops. This work includes out-of-pile experimental results from a single-phase, natural circulation cartridge loop vehicle with geometry relevant to VTR irradiation sites, as well as comparisons between the experimental results and results predicted using the TRAC/RELAP Advanced Computational Engine (TRACE) modeling tool. The experiments were conducted in the thermosyphon test loop (TSTL) facility at Oak Ridge National Laboratory. Comparisons are also made between the current experimental data and results from natural circulation experiments previously conducted in the TSTL in a cartridge vehicle that is similar in design but has smaller flow areas. This cartridge vehicle and the experimental program were developed to add to the single-phase, natural circulation data collected in the previous iteration of the cartridge loop design, which supports future irradiation experiments and adds to a database that is useful for validating computer models. Comparisons of experimental results to TRACE model predictions is a pertinent step in validating the computational tool for supporting future irradiation experiment design and safety calculations, and comparisons to previous cartridge loop results highlight the impact of the design changes made to the test vehicle. The experiments conducted include several steady state tests and transients, including power ramp, loss of offsite power, and loss of external flow scenarios. This work shows that TRACE can accurately predict temperatures and flow conditions in the cartridge loop and the updated vehicle design achieves higher mass flow rates at the same steady state power levels.
This report provides brief descriptions of US Nuclear weapons testing between 1945 and 1992. Editor's note: The United States’ last full-scale nuclear weapons test was conducted 30 years ago on Sept. 23, 1992. Divider was a Los Alamos test and took place in Nevada. It was the nation’s 1,054th nuclear test over a 47-year period.
The 2012 IECC has an airtightness requirement of 3 air changes per hour at 50 Pascals test pressure for both single-family and multifamily construction in Climate Zones 3-8. Other programs (LEED, ASHRAE 189, ASHRAE 62.2) have similar or tighter compartmentalization requirements, driving the need for easier and more effective methods of compartmentalization in multifamily buildings. Builders and practitioners have found that fire-resistance rated wall assemblies are a major source of difficulty in air sealing/compartmentalization, particularly in townhouse construction. This problem is exacerbated when garages are “tucked in” to the units and living space is located over the garages. In this project, Building Science Corporation examined the taping of exterior sheathing details to improve air sealing results in townhouse and multifamily construction, when coupled with a better understanding of air leakage pathways. Current approaches are cumbersome, expensive, time consuming, and ineffective; these details were proposed as a more effective and efficient method. The effectiveness of these air sealing methods was tested with blower door testing, including “nulled” or “guarded” testing (adjacent units run at equal test pressure to null out inter-unit air leakage, or “pressure neutralization”). Pressure diagnostics were used to evaluate unit-to-unit connections and series leakage pathways (i.e., air leakage from exterior, into the fire-resistance rated wall assembly, and to the interior).
Here, we investigated numerical simulation strategies for a long-term test of depressurization-induced gas production from the B1 Sand of Unit B at the Hydrate-01 Stratigraphic Test Well. The main objective of this study was to estimate fluid production rates (with emphasis on water production) under a variety of conditions and production scenarios and contribute new insights to the design and management of the field test. In the first part of the study, we investigated the system response to a three-step depressurization process using two limiting sets of flow properties─the expected maximum and minimum intrinsic and effective permeabilities─for the very heterogeneous reservoir. In the second part, we investigated the effect of the production interval length and placement within the formation relative to the boundaries of the hydrate-bearing unit. The best performing well configuration was used in the third part of the study, which used the most representative subsurface flow properties to investigate the effect of the depressurization strategy on the production performance. The best overall performance (largest gas production with modest water production and a strong response at the observation wells) was obtained with a 10 m-long well situated 3 m below the top of the formation and a three-step depressurization scheme at 15-day intervals to a terminal bottomhole pressure of 2.8 MPa. The overall production performance was enhanced by a faster rate of depressurization. Estimated water production rates in all cases were limited and easily manageable. None of the tested well configurations or depressurization strategies significantly reduced water production without also severely reducing gas production. In all the investigated cases, 95% of the long-term fraction of produced water was replenished by inflows from the boundaries and could not be reduced. These substantial water inflows are an unavoidable feature of HU-B and cannot be easily mitigated by a hydraulic control.
The ECSE Solid State Pulsed Power unit is a high current, high power solid-state pulse modulator. The RG217 V2-V2 Coaxial Cable Assembly is the interface cable between the Solid State Pulser and the load. This document covers the testing procedure for the RG217 V2-V2 Coaxial Cable Assembly. This assembly is comprised of RG217 Coaxial Cable with a LRU Connector on either end. This test procedure verifies the cable is undamaged and assembled correctly, the correct cable connectors are installed properly onto the cable, and that the entire assembly meets conductivity and holdoff voltage requirements. This procedure will verify that the RG217 Coaxial Cable Assembly meets all assembly and functional requirements. In particular, this procedure verifies the Cable Shield and Center Conductor meet conductivity requirements by testing their resistances. Additionally, this procedure ensures the RG217 Coaxial Cable Assembly meets holdoff voltage requirements by applying high voltage and verifying the RG217 Coaxial Cable Assembly does not experience any breakdowns or arcing.
The principal objective of the DM100 tests was to demonstrate the robustness of the vitrification process with respect to feed and glass compositional changes resulting from variations in the simulant-to-additive ratio. The DM100-WV unit was selected for these tests; this melter was used for all of the Part B 1 tests on LAW Envelopes A, B, and C sulfate incorporation that were used to support the subsequent tests on the Pilot Melter as well as for the more recent LAW Sub-Envelope Al, A2, A3 and Cl tests. The same melter was selected for the present tests in order to maintain comparisons between the data sets. In addition, the somewhat smaller glass volume for the same melt surface area as compared to the DM100-BL melter means that more glass turnovers are achieved for a given test duration. The DM100 tests used nominal feed and feed with a 15% surplus in waste simulant. Previous Pilot Melter tests on Envelope A with 10% variations (but with sulfate removal) showed significant impacts on glass production rates that were ultimately corrected by adjustments in the sugar additions. Consequently, robustness with respect to throughput as well as sulfate tolerance are important motivations for these tests.
Fault detection and diagnosis (FDD) represents one of the most active areas of research and commercial product development in the buildings industry. This paper addresses two questions concerning FDD implementation and advancement 1) What are today's users of FDD saving and spending on the technology? 2) What methods and datasets can be used to evaluate and benchmark FDD algorithm performance? Relevant to the first question, 26 organizations that use FDD across a total 550 buildings and 97 M sf achieved median savings of 8%. Twenty-seven FDD users reported that the median base cost for FDD software, annual recurring software cost, and annual labor cost were $8, $2.7 and $8 per monitoring point, with a median implementation size of approximately 1300 points. To address the second question, this paper describes a systematic methodology for evaluating the performance of FDD algorithms, curates an initial test dataset of air handling unit (AHU) system faults, and completes a trial to demonstrate the evaluation process on three sample FDD algorithms. The work provided a first step toward a standard evaluation of different FDD technologies. Finally, it showed the test methodology is indeed scalable and repeatable, provided an understanding of the types of insights that can be gained from algorithm performance testing, and highlighted the priorities for further expanding the test dataset.
Chemical looping combustion (CLC) is an energy conversion technology that can produce concentrated CO 2 stream without the need for a gas separation step, and thus, has the potential to drastically reduce the energy consumption and cost associated with CO 2 capture in power generation. The coal-direct chemical looping (CDCL) process is a CLC technology that uses a moving bed reducer configuration that can directly consume coal as a feedstock without requiring an upstream gasification step. An integrated 250 kW th CDCL pilot unit using iron-based oxygen carriers was constructed and demonstrated for over 1000 h of testing. The principles for the CDCL pilot unit design and operation are summarized in this article. During the 288-hour continuous operation testing, the CDCL pilot unit achieved >96% coal conversion with a CO 2 purity of >97%. Low carbon carryover into the combustor, i.e. <2%, was also confirmed during the test, which shows the capability of the moving bed reactor to retain and convert coal using the oxygen available on the iron-based oxygen carrier. The results from the pilot unit testing confirms the CDCL concept as a promising coal combustion technology for heat and power generation with CO 2 capture.
Industrial process heat (IPH) is one of the largest energy demands in U.S., representing about 10% of all domestic energy consumption. Fuel costs to generate this industrial process heat are generally a top three cost for industry, a major component in American manufacturing competitiveness. Roughly 60% of US IPH demand (about 6,500 TBtu annually) falls in the medium-temperature range of 100–250 °C. While concentrated solar thermal (CST) technologies can provide a cost-effective source of heat in this temperature range, solar intermittency limits their adoption in industries that operate 24/7. Element 16 Technologies, Inc. developed a low-cost sulfur thermal energy storage (TES) technology to bridge this gap by capturing excess solar heat during the day and dispatching it reliably during non-solar hours. The core innovation is the use of sulfur, an abundant, industrial waste byproduct that costs ten times less than molten salt used in commercial TES systems. The overall goal of the project was to advance the design and development of molten sulfur TES to a manufacturing-relevant prototype stage for solar industrial process heat applications, while establishing and validating a realistic pathway to commercial success. Key tasks included corrosion and mechanical durability testing to identify cost-effective materials, design investigations using physics-based simulation tools, techno-economic evaluations of system lifetime costs, and pilot-scale testing for performance verification. Corrosion testing of steel alloys under cyclic molten sulfur conditions showed that austenitic stainless steels in the 300 series performed particularly well, with no structural degradation of welds or joints. Thermal cyclic testing of pilot sulfur TES units up to 1.5 MWh quantified charge/discharge rates, heat losses, round-trip efficiency and validated the system's capability to operate effectively under intermittent charging conditions. A techno-economic model, informed by sulfur TES performance model validated using pilot test data, showed that hybrid solar+sulfur TES+NG boiler systems are economically competitive with incumbent natural gas boilers for multiple locations in the southwest US. In summary, this project established molten sulfur TES as a technically viable pathway to improve economic competitiveness of American manufacturing by lowering the cost of solar industrial process heat.
Recent evaluations of counter-based periodic testing strategies for fault detection in Microprocessor (μP) have shown that only a small set of counters is needed to provide complete coverage of severe faults. Severe faults are defined as faults that leak sensitive information, e.g., an encryption key on the output of a serial port. Alternatively, fault detection can be accomplished by executing instructions that periodically test the control and functional units of the μP. In this paper, we propose a fault detection method that utilizes an ’engineered’ executable program combined with a small set of strategically placed counters in pursuit of a hardware Periodic Built-In-Self-Test (PBIST). We analyze two distinct methods for generating such a binary; the first uses an Automatic Test Generation Pattern (ATPG)-based methodology, and the second uses a process whereby existing counter-based node-monitoring infrastructure is utilized. We show that complete fault coverage of all leakage faults is possible using relatively small binaries with low latency to fault detection and by utilizing only a few strategically placed counters in the μP.
This paper provides an open dataset of measured energy use, solar energy production, and building air leakage data from a 328 m 2 (3,531 ft 2 ) all-electric, zero energy commercial building in Virginia, USA. Over two years of energy use data were collected at 1-hour intervals using circuit-level energy monitors. Over six years of solar energy production data were measured at 1-hour resolution by 56 microinverters (presented as daily and monthly data in this dataset). The building air leakage data was measured post-construction per ASTM-E779 Standard Test Method for Determining Air Leakage Rate by Fan Pressurization and the United States Army Corps (USACE) Building Enclosure Testing procedure; both pressurization and depressurization results are provided. The architectural and engineering (AE) documents are provided to aid researchers and practitioners in reliable modeling of building performance. The paper describes the data collection methods, cleaning, and convergence with weather data. This dataset can be employed to predict, benchmark, and calibrate operational outcomes in zero energy commercial buildings.
The Dual-Axis Radiographic Hydrodynamic Test (DARHT) facility provides flash radiography capabilities using two electron Linear Induction Accelerators (LIA’s). Axis 1 of DARHT produces a 20- MeV, 2-kA, 80-ns-FWHM electron beam. As DARHT Axis 1 enters its twentieth year of operation, the probability of Blumlein Charge Unit (BCU) failure has increased and the risk of a failure on the day of an explosive experiment has become more likely. Replacement time for a BCU is four to six hours. This report examines the radiographic and beam transport effect of operating the accelerator with a missing or reduced charge voltage BCU. The results are compared with normal, full machine operation. A prescription for alternate operation with missing or reduced charge voltage on BCU22 is given.
This project developed an innovative micro-environmental control system (µX) that enables office buildings to reduce energy used for heating and cooling by 15% or more. The µX is a compact, quiet, and ergonomic device that is designed to be installed under an office workstation; it is designed to maintain occupant comfort when room thermostat setpoints are incremented by 4°F or more (warmer in the summer and cooler in the winter) to save energy. When ambient room temperatures are outside of the usual comfort range, the µX maintains occupant comfort by delivering personalized cooling or heating locally to each office worker. The µX provides personalized cooling using a micro vapor compression system that includes a new high-performance micro-scroll compressor and a novel thermal storage unit. The vapor compression system operates at night to freeze a phase-change material (PCM). During the workday, the cooling stored in the PCM is released as a cool breeze of air to make occupants more comfortable. The micro-scroll compressor was developed specifically for this application; it is smaller than any of its type, minimizing the amount of power needed. In heating mode, the µX maintains occupant comfort using a foot heating mat with an infrared reflective box. The µX R&D project was conducted by Syracuse University in collaboration with United Technologies Research Center, Air Innovations, Bush Technical, and Cornell University. Over the course of the initial three-year project, the team developed and evaluated four versions of the unit, advancing the concept to Technology Readiness Level 6. The capabilities of individual proof-of-concept prototypes were verified in tests that were conducted with: 1) units in psychrometric chambers, 2) an instrumented manikin in a laboratory, and 3) human subjects in laboratories that simulate office environments. The tests verified that the µX prototypes met or exceeded all performance targets required to enable office buildings to reduce energy used for heating and cooling by 15% or more by maintaining occupant comfort when thermostat setpoints are incremented by 4°F or more.
Scientists and engineers at Los Alamos National Laboratory are using a unique centrifuge facility to evaluate a flight-ready telemetry system for evaluating a nuclear weapons test missile launch. "The telemetry unit was designed and manufactured by Los Alamos' Intelligence and Space Research Division," said Telemetry Program Manager Myles Fitzgerald. "Telemetry is a data stream of information on temperature, acceleration, vibration, strain, all the conditions a system encounters during a test flight." Because a test missile flight ultimately ends with the test system completely destroyed, telemetry data from the flight must be collected by receiving stations along the flight path. "The purpose of the centrifuge test is to subject the electronics to a high gravitational load (G-load) that's representative of what the system will experience when re-entering the Earth's atmosphere," said weapons test engineer Alex Cusick.
Scientists and engineers at Los Alamos National Laboratory are using a unique centrifuge facility to evaluate a flight-ready telemetry system for evaluating a nuclear weapons test missile launch. "The telemetry unit was designed and manufactured by Los Alamos' Intelligence and Space Research Division," said Telemetry Program Manager Myles Fitzgerald. "Telemetry is a data stream of information on temperature, acceleration, vibration, strain, all the conditions a system encounters during a test flight." Because a test missile flight ultimately ends with the test system completely destroyed, telemetry data from the flight must be collected by receiving stations along the flight path. "The purpose of the centrifuge test is to subject the electronics to a high gravitational load (G-load) that's representative of what the system will experience when re-entering the Earth's atmosphere," said weapons test engineer Alex Cusick.
After thirty-four tests, Hardtack I came to an end on August 18, 1958, with the thirty-fifth and final test, Fig. Four days later, President Dwight Eisenhower told Norris Bradbury, “I am today announcing that the United States will suspend nuclear weapons tests for a period of twelve months and, under certain conditions of progress toward real disarmament, continue that suspension on a year-to-year basis.”1 Although not intended, Eisenhower’s announcement made Fig the last nuclear test conducted in the Marshall Islands.
The Nuclear Non-Proliferation Treaty (NPT) is the most important international security arrangement that we have that is protecting the world community and this has been true for many years. But it did not happen by accident, it is a strategic bargain in which 184 states gave up the right forever to acquire the most powerful weapon ever created in exchange for a commitment from the five states allowed to keep nuclear weapons under the NPT (U.S., U.K., Russia, France and China), to share peaceful nuclear technology and to engage in disarmament negotiations aimed at the ultimate elimination of their nuclear stockpiles. The most important part of this is the comprehensive nuclear test ban (CTBT); the thinking by the 184 NPT non-nuclear weapon states was and is that they understand that the elimination of nuclear weapon stockpiles is a long way off, but at least the NPT nuclear weapon states could stop testing the weapons. The CTBT has been ratified by 161 states but by its terms it can only come into force if 44 nuclear potential states ratify; 36 have of the 44 have ratified it, the remaining eight include the United States and seven others, most of whom are in effect waiting for the United States. No state has tested a nuclear weapon-except for complete outlier North Korea-in 15 years. There appears to be no chance that the U.S. Senate will approve the CTBT for ratification in the foreseeable future, but the NPT may not survive without it. Perhaps it is time to consider an interim measure, for the UN Security Council to declare that any future nuclear weapon test any time, anywhere is a 'threat to peace and security', in effect a violation of international law, which in today's world it clearly would be.