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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 1,657 records · Page 92
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Utah FORGE 5-2557: Trixial Shear and Wellbore Breakout Tests Report and Data

Included are a report and data from triaxial shear tests on simulated Sierra White fault gouge and a borehole stimulation experiment. This serves as a progress report for the Role of Fluid and Temperature in Fracture Mechanics and Coupled Thermo-Hydro-Mechanical-Chemical (THMC) Processes for Enhanced Geothermal Systems project by Purdue University (Utah FORGE R&D project 5-2557). Tests were done with Sierra White granite (SWG) to investigate slip mechanisms and to evaluate the fracture initiation and propagation from a geothermal borehole. Raw data is provided alongside a report on all experimental testing protocols, experimental design, and results.

15 GEOTHERMAL ENERGY↗
DOE OSTI2011

ULTRACOATINGS: Enabling Energy and Power Solutions in High Contact Stress Environments through Next-Generation Nanocoatings

This industry-driven project was the result of a successful response by Eaton Corporation to a DOE/ITP Program, Grand Challenge, industry call. It consisted of a one-year effort in which ORNL participated in the area of friction and wear testing. In addition to Eaton Corporation and ORNL (CRADA), the project team included: Ames Laboratory, who developed the underlying concept for titanium- zirconium-boron (TZB) based nanocomposite coatings; Borg-Warner Morse TEC, an automotive engine timing chain manufacturer in Ithaca, New York, with its own proprietary hard coating; and Pratt & Whitney Rocketdyne, Inc., a dry-solids pump manufacturer in San Fernando Valley, California. This report focuses only on the portion of work that was conducted by ORNL, in a CRADA with Eaton Corporation. A comprehensive final report for the entire effort, which ended in September 2010, has been prepared for DOE by the team. The term 'ultracoatings' derives from the ambitious technical target for the new generation of nanocoatings. As applications, Eaton was specifically considering a fuel pump and a gear application in which the product of the contact pressure and slip velocity during operation of mating surfaces, commonly called the 'PV value', was equal to or greater than 70,000 MPa-m/s. This ambitious target challenges the developers of coatings to produce material capable of strong bonding to the substrate, as well as high wear resistance and the ability to maintain sliding friction at low, energy-saving levels. The partners in this effort were responsible for the selection and preparation of such candidate ultracoatings, and ORNL used established tribology testing capabilities to help screen these candidates for performance. This final report summarizes ORNL's portion of the nanocomposite coatings development effort and presents both generated data and the analyses that were used in the course of this effort. Initial contact stress and speed calculations showed that laboratory tests with available geometries, applied forces, and speeds at ORNL could not reach 70,000 MPa-m/s for the project target, so test conditions were modified to enable screening of the new coating compositions under conditions used in a prior nano-coatings development project with Eaton Corporation and Ames Laboratory. Eaton Innovation Center was able to conduct screening tests at higher loads and speeds, thus providing complementary information on coating durability and friction reduction. Those results are presented in the full team's final report which is in preparation at this writing. Tests of two types were performed at ORNL during the course of this work: (1) simulations of timing chain wear and friction under reciprocating conditions, and (2) pin-on-disk screening tests for bearings undergoing unidirectional sliding. The four materials supplied for evaluation in a timing chain link simulation were hardened type 440B stainless steel, nitrided type 440B stainless steel, vanadium carbide (VC)-coated type 52100 bearing steel, and (ZrTi)B-coated type 52100 bearing steel. Reciprocating wear tests revealed that the VC coating was by far the most wear resistant. In friction, the nitrided stainless steel did slightly better than the other materials.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2011

Mountaineer Commerical Scale Carbon Capture and Storage (CCS) Project

The Final Technical documents all work performed during the award period on the Mountaineer Commercial Scale Carbon Capture & Storage project. This report presents the findings and conclusions produced as a consequence of this work. As identified in the Cooperative Agreement DE-FE0002673, AEP's objective of the Mountaineer Commercial Scale Carbon Capture and Storage (MT CCS II) project is to design, build and operate a commercial scale carbon capture and storage (CCS) system capable of treating a nominal 235 MWe slip stream of flue gas from the outlet duct of the Flue Gas Desulfurization (FGD) system at AEP's Mountaineer Power Plant (Mountaineer Plant), a 1300 MWe coal-fired generating station in New Haven, WV. The CCS system is designed to capture 90% of the CO{sub 2} from the incoming flue gas using the Alstom Chilled Ammonia Process (CAP) and compress, transport, inject and store 1.5 million tonnes per year of the captured CO{sub 2} in deep saline reservoirs. Specific Project Objectives include: (1) Achieve a minimum of 90% carbon capture efficiency during steady-state operations; (2) Demonstrate progress toward capture and storage at less than a 35% increase in cost of electricity (COE); (3) Store CO{sub 2} at a rate of 1.5 million tonnes per year in deep saline reservoirs; and (4) Demonstrate commercial technology readiness of the integrated CO{sub 2} capture and storage system.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2014

Physical and mechanical metallurgy of zirconium alloys for nuclear applications: a multi-scale computational study

In the post-Fukushima world, the stability of materials under extreme conditions is an important issue for the safety of nuclear reactors. Because the nuclear industry is going to continue using advanced zirconium cladding materials in the foreseeable future, it become critical to gain fundamental understanding of the several interconnected problems. First, what are the thermodynamic and kinetic factors affecting the oxidation and hydrogen pick-up by these materials at normal, off-normal conditions, and in long-term storage? Secondly, what protective coatings (if any) could be used in order to gain extremely valuable time at off-normal conditions, e.g., when temperature exceeds the critical value of 2200°F? Thirdly, the kinetics of oxidation of such protective coating or braiding needs to be quantified. Lastly, even if some degree of success is achieved along this path, it is absolutely critical to have automated inspection algorithms allowing identifying defects of cladding as soon as possible. This work strives to explore these interconnected factors from the most advanced computational perspective, utilizing such modern techniques as first-principles atomistic simulations, computational thermodynamics of materials, diffusion modeling, and the morphological algorithms of image processing for defect identification. Consequently, it consists of the four parts dealing with these four problem areas preceded by the introduction and formulation of the studied problems. In the 1st part an effort was made to employ computational thermodynamics and ab initio calculations to shed light upon the different stages of oxidation of ziraloys (2 and 4), the role of microstructure optimization in increasing their thermal stability, and the process of hydrogen pick-up, both in normal working conditions and in long-term storage. The 2nd part deals with the need to understand the influence and respective roles of the two different plasticity mechanisms in Zr nuclear alloys: twinning (at low T) and crystallographic slip (higher T’s). For that goal, a description of the advanced plasticity model is outlined featuring the non-associated flow rule in hcp materials including Zr. The 3rd part describes the kinetic theory of oxidation of the several materials considered to be perspective coating materials for Zr alloys: SiC and ZrSiO 4 . In the 4th part novel and advanced projectional algorithms for defect identification in zircaloy coatings are described. In so doing, the author capitalized on some 12 years of his applied industrial research in this area. Our conclusions and recommendations are presented in the 5th part of this work, along with the list of used literature and the scripts for atomistic, thermodynamic, kinetic, and morphological computations.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Uncertainty Quantification and Management for Multi-scale Nuclear Materials Modeling

Understanding and improving microstructural mechanical stability in metals and alloys is central to the development of high strength and high ductility materials for cladding and cores structures in advanced fast reactors. Design and enhancement of radiation-induced damage tolerant alloys are facilitated by better understanding the connection of various unit processes to collective responses in a multiscale model chain, including: dislocation nucleation, absorption and desorption at interfaces; vacancy production, radiation-induced segregation of Cr and Ni at defect clusters (point defect sinks) in BCC Fe-Cr ferritic/martensitic steels; investigation of interaction of interstitials and vacancies with impurities (V, Nb, Ta, Mo, W, Al, Si, P, S); time evolution of swelling (cluster growth) phenomena of irradiated materials; and energetics and kinetics of dislocation bypass of defects formed by interstitial clustering and formation of prismatic loops, informing statistical models of continuum character with regard to processes of dislocation glide, vacancy agglomeration and swelling, climb and cross slip.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2019

Data associated with, "Methane emissions from gathering and boosting compressor stations in the U.S. Supporting volume 2: Compressor engine exhaust measurements

The in-stack tracer method was used during the field campaign to measure unburned methane entrained in the exhaust of natural gas compressor engines ("combustion slip"). Combustion slipwas estimated by injecting a tracer gas into the exhaust stream at a known flow-rate and measuring concentrations of both the tracer gas and methane at the exhaust stack exit. The total exhaustflow was estimated from the diluted tracer gas concentration measured at the exhaust stack exit.

03 NATURAL GAS↗
DOE OSTI2019

Contact Temperature of a Cuff and a Rotating Shaft

Experimental apparatus is developed for investigating the influence of cuff heating in frictional contact with a rotating shaft. Empirical formulas for the temperature of rubber and polyurethane sealing cuffs as a function of the slip velocity and the excess pressure of the lubricant are determined.

42 ENGINEERING↗
NASA NTRS1994

The Southern California Dense GPS Geodetic Array

The Southern California Earthquake Center is coordinating a effort by scientists at the Jet Propulsion Laboratory, the U.S. Geological Survey, and various academic institutions to establish a dense 250 station, continuously recording GPS geodetic array in southern California for measuring crustal deformation associated with slip on the numerous faults that underlie the major metropolitan areas of southern california.

geodetic array faults crustal deformation slip rat↗
NASA NTRS2012

Characterization of Friction Joints Subjected to High Levels of Random Vibration

This paper describes the test program in detail including test sample description, test procedures, and vibration test results of multiple test samples. The material pairs used in the experiment were Aluminum-Aluminum, Aluminum- Dicronite coated Aluminum, and Aluminum-Plasmadize coated Aluminum. Levels of vibration for each set of twelve samples of each material pairing were gradually increased until all samples experienced substantial displacement. Data was collected on 1) acceleration in all three axes, 2) relative static displacement between vibration runs utilizing photogrammetry techniques, and 3) surface galling and contaminant generation. This data was used to estimate the values of static friction during random vibratory motion when "stick-slip" occurs and compare these to static friction coefficients measured before and after vibration testing.

aluminum↗
NASA NTRS2017

Effect of Angle of Attack on Slope Climbing Performance

Ascending steep slopes is often a very difficult challenge for off-road vehicles, whether on Earth or on extraterrestrial bodies. This challenge is even greater if the surface consists of loose granular soil that does not provide much shear strength. This study investigated how the path at which a vehicle traverses a slope, specifically the angle that it is commanded to drive relative to the base of the hill (the angle of attack), can affect its performance. A vehicle was driven in loose sand at slope angles up to 15 degrees and angles of attack ranging from 10 to 90 degrees. A novel photogrammetry technique was implemented to both track vehicle motion and create a three-dimensional profile of the terrain. This allowed for true wheel sinkage measurements. The study showed that though low angles of attack result in lower wheel slip and sinkage, the efficiency of the vehicles uphill motion increased at higher angles of attack. For slopes up to 15 degrees, a 90 degree angle of attack provided the greatest likelihood of successful ascent.

wheel↗
DOE OSTI2012

Bunch Coalescing in a Helical Channel

A high-luminosity Muon Collider requires bunch recombination for optimal luminosity. In this paper, we take advantage of the large slip factor attainable in a helical transport channel (HTC) to coalesce bunches of muons into a single one over a shorter distance than can be achieved over a straight channel.

43 PARTICLE ACCELERATORS↗
DOE OSTI2021

Field Data Analysis and Modeling of Drillstring Vibrations to Identify Inefficiency in Deep Geothermal Drilling

One challenge that hinders efficient drilling and causes downhole tool failures is severe drillstring vibrations. The objective of this paper is to identify the root cause of drillstring vibrations in deep geothermal wells and investigate their effect on drilling performance using data analytics and vibration modeling. A near-bit sub was utilized to collect vibration data, where the burst data was used to obtain the drillstring torsional natural frequency. The data showed that the highest lateral acceleration and stick-slip severities (SSS) occur at the higher mechanical specific energy (MSE) range, while the low vibration levels were encountered in the optimum range of the MSE curve. The elevated SSS levels consistently occur at the low to mid-range of applied RPM and the highest sonic velocity. Additionally, the lateral acceleration levels are higher at the low to mid-range of the applied RPM. The effect of drillstring vibration on drilling performance was recognized by the presented MSE analysis.

15 GEOTHERMAL ENERGY↗
DOE OSTI2012

A study on the effect of various design parameters on the natural circulation flow rate of the ex-vessel core catcher cooling system of EU-APR1400

In this paper, a study on the effect of various design parameters such as the channel gap width, heat flux distribution, down-comer pipe size and two-phase flow slip ratio on the natural circulation flow rate is performed based on a physical model for a natural circulation flow along the flow path of the ex-vessel core catcher cooling system of an EU-APR1400, and these effects on the natural circulation flow rate are analyzed and compared with the minimum flow rate required for the safe operation of the system. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2014

Large earthquake processes in the northern Vanuatu subduction zone

Abstract The northern Vanuatu (formerly New Hebrides) subduction zone (11°S to 14°S) has experienced large shallow thrust earthquakes with M w > 7 in 1966 ( M S 7.9, 7.3), 1980 ( M w 7.5, 7.7), 1997 ( M w 7.7), 2009 ( M w 7.7, 7.8, 7.4), and 2013 ( M w 8.0). We analyze seismic data from the latter four earthquake sequences to quantify the rupture processes of these large earthquakes. The 7 October 2009 earthquakes occurred in close spatial proximity over about 1 h in the same region as the July 1980 doublet. Both sequences activated widespread seismicity along the northern Vanuatu subduction zone. The focal mechanisms indicate interplate thrusting, but there are differences in waveforms that establish that the events are not exact repeats. With an epicenter near the 1980 and 2009 events, the 1997 earthquake appears to have been a shallow intraslab rupture below the megathrust, with strong southward directivity favoring a steeply dipping plane. Some triggered interplate thrusting events occurred as part of this sequence. The 1966 doublet ruptured north of the 1980 and 2009 events and also produced widespread aftershock activity. The 2013 earthquake rupture propagated southward from the northern corner of the trench with shallow slip that generated a substantial tsunami. The repeated occurrence of large earthquake doublets along the northern Vanuatu subduction zone is remarkable considering the doublets likely involved overlapping, yet different combinations of asperities. The frequent occurrence of large doublet events and rapid aftershock expansion in this region indicate the presence of small, irregularly spaced asperities along the plate interface.

Cleveland, K. Michael↗
DOE OSTI2015

An empirical study of the distribution of earthquakes with respect to rock type and depth

Whether fault slip occurs seismically or aseismically depends on the frictional properties of the fault, which might be expected to depend on rock type and depth, as well as other factors. To view the effect of rock type and depth on the distribution of earthquakes, we compare geologic models of the San Francisco Bay and the Southern California regions to the distribution of seismicity. We normalize the number of earthquakes within each rock type and depth interval by the corresponding volume to determine the earthquake density. Earthquake density is confirmed primarily by depth, while whether the rock is sedimentary or basement has only a secondary, depth-dependent effect on the earthquake density. At very shallow depths, there is no difference in earthquake density between sedimentary and basement rocks. The earthquake density of basement rocks increases with depth more rapidly than that of sedimentary rocks to a similar but shallower maximum.

3‐D geologic models↗