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Nanosensors as Reservoir Engineering Tools to Map Insitu Temperature Distributions in Geothermal Reservoirs

Description: The feasibility of using nanosensors to measure temperature distribution and predict thermal breakthrough in geothermal reservoirs is addressed in this report. Four candidate sensors were identified: melting tin-bismuth alloy nanoparticles, silica nanoparticles with covalently-attached dye, hollow silica nanoparticles with encapsulated dye and impermeable melting shells, and dye-polymer composite time-temperature indicators. Four main challenges associated with the successful implementation of temperature nanosensors were identified: nanoparticle mobility in porous and fractured media, the collection and detection of nanoparticles at the production well, engineering temperature sensing mechanisms that are both detectable and irreversible, and inferring the spatial geolocation of temperature measurements in order to map temperature distribution. Initial experiments were carried out to investigate each of these challenges. It was demonstrated in a slim-tube injection experiment that it is possible to transport silica nanoparticles over large distances through porous media. The feasibility of magnetic collection of nanoparticles from produced fluid was evaluated experimentally, and it was estimated that 3% of the injected nanoparticles were recovered in a prototype magnetic collection device. An analysis technique was tailored to nanosensors with a dye-release mechanism to estimate temperature measurement geolocation by analyzing the return curve of the released dye. This technique was used in a hypothetical example problem, and good estimates of geolocation were achieved. Tin-bismuth alloy nanoparticles were synthesized using a sonochemical method, and a bench heating experiment was performed using these nanoparticles. Particle growth due to melting was observed, indicating that tin-bismuth nanoparticles have potential as temperature nanosensors
Date: June 15, 2011
Creator: Ames, Morgan
Partner: UNT Libraries Government Documents Department

Errors in skin temperature measurements.

Description: Numerical simulation is used to investigate the accuracy of a direct-contact device for measuring skin-surface temperature. A variation of thermal conductivity of the foam has greater effect on the error rather than a variation of the blood perfusion rate. For a thermal conductivity of zero, an error of 1.5 oC in temperature was identified. For foam pad conductivities of 0.03 and 0.06 W/m-oC, the errors are 0.5 and 0.15 oC. For the transient study, with k=0 W/m-oC, it takes 4,900 seconds for the temperature to reach steady state compared with k=0.03 W/m-oC and k=0.06 W/m-oC where it takes 3,000 seconds. The configuration without the foam and in presence of an air gap between the skin surface and the sensor gives the most uniform temperature profile.
Date: December 2008
Creator: Dugay, Murielle
Partner: UNT Libraries


Description: The purpose of the present effort was to demonstrate 'on the fly' temperature measurement of railgun armatures on a bench top railgun. The effort builds on the previous test that utilized a portable unit with armature speeds ranging from 50 to 90 m/s. The tests described here involved higher speeds, ranging from 300 to 500 m/s. The method to accomplish the measurement involves pulsed laser illumination of a phosphor-coated armature. The duration of the ensuing fluorescence indicates temperature. The measured temperatures, obtained both inside the muzzle and outside in free flight, ranged between 80 to 110 C. The required pulsed fluorescence was made possible by successfully sensing the position of the armature while traveling within the laser illumination and fluorescence sensing fields-of-view. A high-speed camera also captured images of the moving armatures after exiting the railgun. These images sometimes included the fluorescing region of the phosphor coating.
Date: December 1, 2005
Creator: Allison, Stephen W; Cates, Michael R; Goedeke, Shawn; Crawford, M. T.; Ferraro, S. B.; Surls, D. et al.
Partner: UNT Libraries Government Documents Department

Heat transfer analysis of sludge storage in the K east basinweasel pit

Description: This document estimates the temperature of the sludge inventory projected to be stored in the K East Basin Weasel Pit during the Spent Nuclear Fuel Project. Hydrogen generation rates are also estimated. Since many of the needed sludge properties are not well known, the analysis considered a range values to show the sensitivity of the results.
Date: February 21, 1997
Creator: Bergsman, K.H.
Partner: UNT Libraries Government Documents Department

Development of Advanced Sensor Technologies for the United States Glass Industry - Final Report - 07/20/1995 - 08/19/1999

Description: The glass industry, with support from the U.S. Department of Energy (DOE), undertook a project to significantly improve temperature measurement in glass melters, thereby reducing energy usage through improved process control. AccuTru International determined that a new kind of protective sheath would improve the life and range of applications of the temperature measuring thermocouples. In cooperation with Corning, Inc., the University of Missouri-Rolla ceramics department conducted tests on a proprietary alumina sheath technology, which shows significant promise. In addition, AccuTru obtained DOE funding to develop a self-verifying sensor. The new sensor, with alumina sheath, was tested at a Corning facility, and the results exceeded expectations. Areas for additional development efforts were identified.
Date: December 1, 1999
Creator: Conner, B. L. & Cannon, C.
Partner: UNT Libraries Government Documents Department

Final Scientific Report

Description: This project investigated the feasibility of developing a remote temperature measurement instrument for energy-intensive industries. Existing remote temperature measurement techniques based on infrared radiation fail when excessive amounts of dust, smoke, or other particulates are present. We found that a remote temperature measurement instrument using microwaves demonstrated performance superior to infrared instrumentation in laboratory and field trials when dust or steam was present. Since improved temperature measurement helps improve energy efficiency and quality in a wide variety of industrial processes, making the new microwave instrument commercially available should lead to reduced energy usage, improved quality, and better competitiveness in a number of energy-intensive industries such as food processing and cement manufacturing. These improvements can lead to lower-priced products of improved quality for the consumer, and can contribute to the nation's energy independence.
Date: January 31, 2006
Creator: Stephan, K. D.
Partner: UNT Libraries Government Documents Department

Laboratory measurements on core-scale sediment/hydrate samples topredice reservoir behavior

Description: Measurements on hydrate-bearing laboratory and field samplesare necessary in order to provide realistic bounds on parameters used innumerically modeling the production of natural gas from hydrate-bearingreservoirs. The needed parameters include thermal conductivity,permeability, relative permeability-saturation(s) relationships, andcapillary pressure-saturation(s) relationships. We have developed atechnique to make hydrate-bearing samples ranging in scale from coreplug-size to core-size in the laboratory to facilitate making thesemeasurements. In addition to pressure and temperature measurements, weuse x-ray computed tomography scanning to provide high-resolution dataproviding insights on processes occurring in our samples. Several methodsare available to make gas hydrates in the laboratory, and we expect thatthe method used to make the hydrate will impact the behavior of thehydrate sample, and the parameters measured.
Date: November 2, 2005
Creator: Kneafsey, Timothy J.; Seol, Yongkoo; Moridis, George J.; Tomutsa,Liviu & Freifeld, Barry M.
Partner: UNT Libraries Government Documents Department


Description: This test established feasibility for 'on the fly' temperature measurements of rail gun projectiles. In addition, an approach for projectile velocity measurement was also demonstrated. Insight was gained into other useful optical and fiberoptic diagnostic approaches. Instantaneous diagnostics could be critical for achieving further improvements in rail gun operation. They have the potential to enable design enhancements by providing information on the state of the armature and its relationship to the rail as it proceeds down the bore. To that end, the following was accomplished: (1) Optical fibers successfully delivered optical excitation and returned reflective and fluorescence signals as desired. (2) Luminescent coatings survived multiple firings--approximately 40 shots. (3) Optical triggering effectively synchronized an ultraviolet laser pulse to strike the moving armature. (4) Velocity measurements were successfully accomplished by either triggering on the armature front edge using two red diode lasers or by using a single laser and grooved marks a known distance apart on the armature surface. (5) Velocities ranged from 19 to 88 m/s. (6) Temperatures of 30 to 92 C were measured with a precision of about 2 C-: (a) This precision was achieved with a single laser shot and (b) Motion effect was observed but a methodology adequately corrected the result. The correction was only about 2 C. (7) Adequate signal-to-noise and measurement precision was achieved with a single laser shot.
Date: March 1, 2005
Creator: Allison, Stephen W; Cates, Michael R; Goedeke, Shawn; Crawford, M. T.; Ferraro, S. B. & Akerman, A.
Partner: UNT Libraries Government Documents Department

Multi-channel optical pyrometer for sub-nanosecond temperature measurements at NDCX-I/II

Description: We present a detailed technical description of a fast multi-channel pyrometer designed for warm-dense-matter (WDM) experiments with intense heavy ion beams at the neutralized-drift-compression-experiment linear accelerator (NDCX-I/II) at Lawrence Berkeley National Laboratory (LBNL). The unique features of the described instrument are its sub-nanosecond temporal resolution (100 ps rise-time) and a broad range, 1,500 K - 12,000 K of measurable brightness temperatures in the visible and near-infrared regions of the spectrum. The working scheme, calibration procedure, experimental data obtained with the pyrometer and future applications are presented.
Date: April 13, 2011
Creator: Ni, P.A.; Bieniosek, F.M. & Waldron, W.L.
Partner: UNT Libraries Government Documents Department

Investigation of the Downwelling LW Differences Between the Niamey AMF Main and Supplementary Sites

Description: The overall average downwelling longwave (LW) measured at the Niamey supplementary facility (S1) is 6-8 Wm-2 less than that measured by the two instruments located at the ARM Mobile Facility (AMF) main (N1) site. Examination of all other data available at both sites does not reveal any overarching differences that suggest this should be the case. However, examination of the pyrgeometer case and dome temperatures do suggest that the S1 values are also anomalously low, which in turn would explain the downwelling LW anomaly since the LW is calculated using these temperatures. Our recommendation then is to normalize the S1 data to the average N1 value by applying an adjustment factor to the S1 downwelling pyrgeometer case and dome temperatures (in Kelvin), then recalculating the downwelling LW values. The adjustment factor (0.00305) has been determined as that factor that brings the overall average S1 LWdn to agree with the overall average of the two N1 LWdn data series. We note that there is no reason to expect that the two site averages would actually be exactly equal to one another, and thus our recommendation is viewed as likely moving the S1 data in the right direction and by normalizing to the N1 average will help facilitate more meaningful temporal variability studies at least. It is also strongly recommended that for all future AMF deployments where supplementary sites will also be deployed, that the supplementary instrument systems (complete) be assembled as they will be operated in the field and run for at least a few days beside the corresponding AMF main site instruments, both at the beginning and end of the AMF field campaign. This is absolutely crucial so that all the measurements can be compared pre- and post-experiment to properly relate these measurements and systems, and to detect measurement anomalies ...
Date: April 1, 2008
Creator: Long, CN; Gotseff, P & Dutton, EG
Partner: UNT Libraries Government Documents Department


Description: This project explores the thermodynamics of dynamic deformation and failure of materials using high-speed spatially-resolved infrared (IR) measurements of temperature. During deformation mechanical work is converted to different forms of energy depending on the deformation processes. For example, it can be dissipated as heat in purely plastic deformation, stored as strain energy in dislocations in metals and in oriented polymeric molecular structures, and expended during the generation of new surfaces during damage and fracture. The problem of how this work is converted into these various forms is not well understood. In fact, there exists a controversy for the relatively simple case regarding the amount of work dissipated as heat during uniform plastic deformation. The goals of this work are to develop dynamic IR temperature measurement techniques and then apply them to gain a better understanding of the dynamic failure processes in both metals and polymeric composite materials. The experimental results will be compared against predictions of existing constitutive models and guide the development of higher fidelity models if needed.
Date: February 13, 2006
Creator: McElfresh, M & DeTeresa, S
Partner: UNT Libraries Government Documents Department

Systems and Methods for Integrated Emissivity and Temperature Measurement of a Surface

Description: A multi-channel spectrometer and a light source are used to measure both the emitted and the reflected light from a surface which is at an elevated temperature relative to its environment. In a first method, the temperature of the surface and emissivity in each wavelength is calculated from a knowledge of the spectrum and the measurement of the incident and reflected light. In the second method, the reflected light is measured from a reference surface having a known reflectivity and the same geometry as the surface of interest and the emitted and the reflected light are measured for the surface of interest. These measurements permit the computation of the emissivity in each channel of the spectrometer and the temperature of the surface of interest.
Date: November 8, 2005
Creator: Poulsen, Peter
Partner: UNT Libraries Government Documents Department

Time-resolved Temperature Measurements in SSPX

Description: We seek to measure time-resolved electron temperatures in the SSPX plasma using soft X-rays from free-free Bremsstrahlung radiation. To increase sensitivity to changes in temperature over the range 100-300 eV, we use two photodiode detectors sensitive to different soft X-ray energies. The detectors, one with a Zr/C coating and the other with a Ti/Pd coating, view the plasma along a common line of sight tangential to the magnetic axis of the spheromak, where the electron temperature is a maximum. The comparison of the signals, over a similar volume of plasma, should be a stronger function of temperature than a single detector in the range of Te< 300 eV. The success of using photodiodes to detect changing temperatures along a chord will make the case for designing an array of the detectors, which could provide a time changing temperature profile over a larger portion of the plasma.
Date: August 14, 2006
Creator: Ludington, A R; Hill, D N; McLean, H S; Moller, J & Wood, R D
Partner: UNT Libraries Government Documents Department


Description: Experiments and calculations were conducted with a 0.13 mm fine wire thermocouple within a naturally-aspirated Gill radiation shield to assess and improve the accuracy of air temperature measurements without the use of mechanical aspiration, wind speed or radiation measurements. It was found that this thermocouple measured the air temperature with root-mean-square errors of 0.35 K within the Gill shield without correction. A linear temperature correction was evaluated based on the difference between the interior plate and thermocouple temperatures. This correction was found to be relatively insensitive to shield design and yielded an error of 0.16 K for combined day and night observations. The correction was reliable in the daytime when the wind speed usually exceeds 1 m s{sup -1} but occasionally performed poorly at night during very light winds. Inspection of the standard deviation in the thermocouple wire temperature identified these periods but did not unambiguously locate the most serious events. However, estimates of sensor accuracy during these periods is complicated by the much larger sampling volume of the mechanically-aspirated sensor compared with the naturally-aspirated sensor and the presence of significant near surface temperature gradients. The root-mean-square errors therefore are upper limits to the aspiration error since they include intrinsic sensor differences and intermittent volume sampling differences.
Date: September 9, 2009
Creator: Kurzeja, R.
Partner: UNT Libraries Government Documents Department

Temperature measurements of partially-melted tin as a function of shock pressure

Description: Equilibrium equation of state theory predicts that the free surface release temperature of shock loaded tin will show a plateau of 505 K in the pressure range from 19.5 to 33.0 GPa, corresponding to the solid-liquid mixed-phase region. In this paper we report free surface temperature measurements on shock-loaded tin from 15 to 31 GPa using multi-wavelength optical pyrometry. The shock waves were generated by direct contact of detonating high explosive with the sample. The pressure in the sample was determined by free surface velocity measurements using Photon Doppler Velocimetry. The emitted thermal radiance was measured at four wavelength bands in the near IR region from 1.5 to 5.0 {micro}m. The samples in most of the experiments had diamond-turned surface finishes, with a few samples being polished or ball rolled. At pressures higher than 25 GPa the measured free surface temperatures were higher than the predicted 505 K and increased with increasing pressure. This deviation could be explained by hot spots and/or variations in surface emissivity and requires a further investigation.
Date: January 1, 2009
Creator: Seifter, Achim; Furlanetto, Michael R; Holtkamp, David B; Obst, Andrew W; Payton, J R; Stone, J B et al.
Partner: UNT Libraries Government Documents Department

Multispectral thermal imager observations of the moon during total eclipse.

Description: Lunar eclipse temperature measurements are sensitive to rock populations because surfaces with abundant exposed rock have much higher mean thermal inertias than surfaces dominated by fine powders . When the Moon passes into the I :arth's shadow, the abrupt reduction in insolation causes surfacc elements to cool at rates which are ILnctions oftheir thermal inertia . The rock population is a lunction of the exposure of a surface unit, originally composed of solid igneous rock or impact mclt, to the impact flux of modest sized projectiles. With time, a competent surface such as a lava flow field or an impact melt sheet will be comminuted by the impact flux reducing the ratio of coarse to fine particles . In principle, thermal measurements taken during lunar eclipse can be used as a measure of the relative age of surface units .
Date: January 1, 2003
Creator: Lawson, S. L. (Stefanie L.); Rodger, A. P. (Andrew Paul); Bender, S. C. (Steven C.); Lucey, P. G. (Paul G.) & Henderson, B. G. (Bradley G.)
Partner: UNT Libraries Government Documents Department

A Measurement of the Cosmic Background Radiation Temperature at3.0 cm

Description: We describe a measurement of the cosmic background radiation temperature at a wavelength of 3.0 cm. The experiment was made in conjunction with measurements at four other wavelengths in an effort to measure the long wavelength spectrum to high accuracy. The result at 3 cm, T{sub CBR} = 2.91 {+-} 0.19 K, is in good agreement with the values at neighboring wavelengths, and consistent with previous results.
Date: June 1, 1983
Creator: Friedman, S.D.; Smoot, G.F.; De Amici, G. & Witebsky, C.
Partner: UNT Libraries Government Documents Department

An Analysis of Recent Measurements of the Temperature of theCosmic Microwave Background Radiation

Description: This paper presents an analysis of the results of recent temperature measurements of the cosmic microwave background radiation (CMBR). The observations for wavelengths longer than 0.1 cm are well fit by a blackbody spectrum at 2.74 {+-} 0.02 K; however, including the new data of Matsumoto et al. (1987) the result is no longer consistent with a Planckian spectrum. The data are described by a Thomson-distortion parameter u = 0.021 {+-} 0.002 and temperature 2.823 {+-} 0.010 K at the 68% confidence level. Fitting the low-frequency data to a Bose-Einstein spectral distortion yields a 95% confidence level upper limit of 1.4 x 10{sup -2} on the chemical potential {mu}{sub 0}. These limits on spectral distortions place restrictions on a number of potentially interesting sources of energy release to the CMBR, including the hot intergalactic medium proposed as the source of the X-ray background.
Date: July 1, 1987
Creator: Smoot, G.; Levin, S.M.; Witebsky, C.; De Amici, G. & Rephaeli, Y.
Partner: UNT Libraries Government Documents Department

A high-speed four-channel infrared pyrometer

Description: A high-speed, four-wavelength pyrometer has been developed for dynamic temperature measurements on samples that are heated by shock compression. The pyrometer uses a pair of off-axis parabolic mirrors to collect radiance emitted from a target of 1 mm in diameter. A single optical fiber delivers the collected radiant flux to the detector housing. Three dichroic beam splitters are used to spectrally split the light into four beams that are then focused onto an equal number of LN2-cooled InSb photodetectors. Broad bandwidth interference filters that are nominally centered at 1.8, 2.4, 3.4, and 5.0 {micro}m define the wavelength ranges of the four channels. The blackbody-temperature threshold of the pyrometer is at about 400 K. The signals are recorded at intervals as short as 20 ns using a four-channel digital oscilloscope. Procedures for calibration and temperature measurements are described.
Date: January 1, 2002
Creator: Boboridis, K. & Obst, A. W. (Andrew W.)
Partner: UNT Libraries Government Documents Department


Description: Measurements of the time-dependent absolute temperature of surfaces shocked using high explosives (HE) provide valuable constraints on the equations-of-state (EOS) of materials and on the state of ejecta from those surfaces. In support of these dynamic surface temperature measurements, techniques for measuring the dynamic surface emissivity of shocked metals in the near infrared (IR) are being developed. These consist of time-dependent laser ellipsometric measurements, using several approaches. A discussion of these ellipsometric techniques is included here. Ellipsometry permits an accurate determination of the dynamic emissivity at a given wavelength, and may also provide a signature of melt in shocked metals.
Date: January 1, 2001
Creator: Obst, A. W. (Andrew W.); Alrick, K.R. (Keith R.); Boboridis, K.; Buttler, William T.; Lamoreaux, Steve Keith; Montgomery, S. L. (Stefanie L.) et al.
Partner: UNT Libraries Government Documents Department