Sulfur removal in advanced two stage pressurized fluidized bed combustion. Technical report, March 1--May 31, 1995 (open access)

Sulfur removal in advanced two stage pressurized fluidized bed combustion. Technical report, March 1--May 31, 1995

The objective of this study is to obtain data on the rates and the extent of sulfation reactions involving partially sulfided calcium-based sorbents, and oxygen as well as sulfur dioxide, at operating conditions closely simulating those prevailing in the second stage (combustor) of Advanced Two-Stage Pressurized Fluidized-Bed Combustors. In these systems the CO{sub 2} partial pressure generally exceeds the equilibrium value for calcium carbonate decomposition. Therefore, calcium sulfate is produced through the reactions between SO{sub 2} and calcium carbonate as well as the reaction between calcium sulfide and oxygen. To achieve this objective, the rates of reaction involving SO{sub 2} and oxygen, calcium sulfide and calcium carbonate will be determined by conducting tests in a pressurized thermogravimetric analyzer unit. The sulfate tests conducted during this quarter, focused on the determination of the rate of sulfation reaction involving partially sulfided half-calcined dolomite and oxygen. The test parameters included CO{sub 2} and O{sub 2} concentrations, reaction temperature and pressure, as well as the sorbent particle size. The results obtained during this quarter suggest that the rate of sulfation reaction involving partially sulfided half-calcined dolomite and oxygen is very fast at temperatures above 850 C which rapidly increases with increasing temperature, achieving more …
Date: December 31, 1995
Creator: Abbasian, J.
Object Type: Report
System: The UNT Digital Library
Development of regenerable copper-based sorbents for hot gas cleanup. Technical report, September 1, 1995--November 30, 1995 (open access)

Development of regenerable copper-based sorbents for hot gas cleanup. Technical report, September 1, 1995--November 30, 1995

The overall objective of this study is to determine the effectiveness of the copper-chromite sorbent (developed in previous ICCI-funded projects) for longer duration application under optimum conditions in the temperature range of 550{degrees}-650{degrees}C to minimize sorbent reduction and degradation during the cyclic process. To achieve this objective, several formulations of copper chromite sorbents are prepared. These sorbent formulations are screened for their desulfurization and regeneration capability at predetermined temperatures and gas residence times. The durability of the best sorbent formulation identified in the screening tests is evaluated in ``long-term`` durability tests conducted at the optimum operating conditions. This includes testing the sorbent in pellet and granular forms in packed- and fluidized-bed reactors. During this quarter, twenty one copper chromite-based sorbent formulations were prepared. Two sorbent formulations that have acceptable crush strength, designated as CuCr-10 and CuCr-21, were tested over 5 and 6 cycles respectively. The results indicate that both sorbents are reactive toward H{sub 2}S at 650{degrees}C and that the reactivity of the sorbents are relatively constant over the first 5 to 6 cycles. The H{sub 2}S prebreakthrough concentrations were generally about 20 to 30 ppm, making them suitable for IGCC application.
Date: December 31, 1995
Creator: Abbasian, J.; Slimane, R.B. & Hill, A.H.
Object Type: Report
System: The UNT Digital Library
Stabilization of spent sorbents from coal-based power generation processes. Technical report, September 1, 1995--November 30,1995 (open access)

Stabilization of spent sorbents from coal-based power generation processes. Technical report, September 1, 1995--November 30,1995

The overall objective of this study is to determine the effect of implementation of the new and more stringent EPA Protocol Test Method involving sulfide containing waste, on the suitability of the oxidized spent sorbents from gasification of of high sulfur coals for disposal in landfills, and to determine the optimum operating conditions in a ``final`` hydrolysis stage for conversion of the residual calcium sulfide in these wastes to materials that are suitable for disposal in landfills. An additional objective is to study the effect of ash on the regeneration and ash-sorbent separation steps in the Spent Sorbent Regeneration Process (SSRP). To achieve these objectives, a large set of oxidized samples of sulfided calcium-based sorbents (produced in earlier ICCI-funded programs) as well as oxidized samples of gasifier discharge (containing ash and spent sorbent) are tested according to the new EPA test protocol. Samples of the oxidized spent sorbents that do not pass the EPA procedure are reacted with water and carbon dioxide to convert the residual calcium sulfide to calcium carbonate. During this quarter, samples of oxidized sulfided calcium-based sorbents, including untreated calcium sulfide-containing feed materials, were analyzed using both weak acid and more stringent strong acid tests. Preliminary analysis …
Date: December 31, 1995
Creator: Abbassian, J. & Hill, A.H.
Object Type: Report
System: The UNT Digital Library
Advanced waste forms from spent nuclear fuel (open access)

Advanced waste forms from spent nuclear fuel

More than one hundred spent nuclear fuel types, having an aggregate mass of more than 5000 metric tons (2700 metric tons of heavy metal), are stored by the United States Department of Energy. This paper proposes a method for converting this wide variety of fuel types into two waste forms for geologic disposal. The method is based on a molten salt electrorefining technique that was developed for conditioning the sodium-bonded, metallic fuel from the Experimental Breeder Reactor-II (EBR-II) for geologic disposal. The electrorefining method produces two stable, optionally actinide-free, high-level waste forms: an alloy formed from stainless steel, zirconium, and noble metal fission products, and a ceramic waste form containing the reactive metal fission products. Electrorefining and its accompanying head-end process are briefly described, and methods for isolating fission products and fabricating waste forms are discussed.
Date: December 31, 1995
Creator: Ackerman, J.P. & McPheeters, C.C.
Object Type: Report
System: The UNT Digital Library
Environmental impacts of ocean disposal of CO{sub 2} (open access)

Environmental impacts of ocean disposal of CO{sub 2}

This project has examined the impacts from the marine disposal of carbon dioxide based on the current state of knowledge.
Date: December 31, 1995
Creator: Adams, E.; Herzog, H.; Auerbach, D. & Caulfield, J.
Object Type: Article
System: The UNT Digital Library
Deflagration-induced pressure and temperature transients in a waste storage facility (open access)

Deflagration-induced pressure and temperature transients in a waste storage facility

This paper presents a study for a facility where a deflagration of flammable vapors takes place, and the generated pressure and temperature transients are analyzed to evaluate the pressure differentials induced on the various components of the facility to assesses their structural integrity. The temperature profiles are also analyzed to assess the qualification of the equipment that is required to operate during and after such an accident.
Date: December 31, 1995
Creator: Ades, M. J. & Polizzi, L. M.
Object Type: Article
System: The UNT Digital Library
Atomic structure of active sites in O{sub 2} reduction on Au(111)/Tl{sub ad} electrodes in acid and alkaline solutions (open access)

Atomic structure of active sites in O{sub 2} reduction on Au(111)/Tl{sub ad} electrodes in acid and alkaline solutions

Surface x-ray scattering has been used to determine the structure of Tl adlayers on the Au(111) electrode surface during the course of 0{sub 2} reduction. 0. reduction is considerably catalyzed by Ti adlayers on Au(111). The half-wave potential is shifted to more positive values in the presence of the Ti adlayer. In both, acid and alkaline solutions TI causes a change in the reaction mechanism from a 2-ereduction to a 4e-reduction in a limited potential range. The in-plane X-ray diffraction measurements revealed that the close-packed rotated-hexagonal Ti phase, which exists in the potential range between -0.4V and the bulk TI deposition at {approx}{minus} 0.7V, has a lower activity for 0. reduction than the low-coverage phases in both solutions. It supports a 2e-reduction.0{sub 2} reduction does not change the TI coverage in this phase but causes a significant decrease of the in-plane diffracted intensity. The lower coverage phases which exist at more positive potentials, viz., aligned hexagonal in alkaline solution and patches of the (2 {times} 2)TI phase in acid solution, are conducive to a 4e-reduction. The diffraction intensity from these two phases, however, vanishes quickly during O{sub 2} reduction. It appears that the TI coverage remains on the surface unchanged. …
Date: December 31, 1995
Creator: Adzic, R. R. & Wang, J. X.
Object Type: Article
System: The UNT Digital Library
LLW Notes, Volume 10, Number 5, July 1995 (open access)

LLW Notes, Volume 10, Number 5, July 1995

Newsletter distributed to the Low-Level Radioactive Waste Forum members describing current news, policies, and legislation, as well as other information relevant to the management of low-level radioactive waste.
Date: July 31, 1995
Creator: Afton Associates, Inc.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Intercooler Flow Path for Gas Turbines: CFD Design and Experiments (open access)

Intercooler Flow Path for Gas Turbines: CFD Design and Experiments

The Advanced Turbine Systems (ATS) program was created by the U.S. Department of Energy to develop ultra-high efficiency, environmentally superior, and cost competitive gas turbine systems for generating electricity. Intercooling or cooling of air between compressor stages is a feature under consideration in advanced cycles for the ATS. Intercooling entails cooling of air between the low pressure (LP) and high pressure (HP) compressor sections of the gas turbine. Lower air temperature entering the HP compressor decreases the air volume flow rate and hence, the compression work. Intercooling also lowers temperature at the HP discharge, thus allowing for more effective use of cooling air in the hot gas flow path.
Date: December 31, 1995
Creator: Agrawal, A. K.; Gollahalli, S. R. & Carter, F. L.
Object Type: Article
System: The UNT Digital Library
A new look at positron production from heavy-ion collisions: Results from apex (open access)

A new look at positron production from heavy-ion collisions: Results from apex

A new solenoidal spectrometer, designed to study the production mechanism of electrons and positrons in heavy-ion collisions, has been constructed at Argonne National Laboratory. The spectrometer has been used to study the {sup 238}U + {sup 181}Ta system at 5.95, 6.10, and 6.30 MeV/u and the {sup 238}U + {sup 232}Th system at 5.95 MeV/u. These bombarding energies cover the energy region where previous experiments have reported sharp sum-energy lines. No evidence is found for sharp peaks in the present data. For the specific case of the isolated decay of a neutral particle of mass 1.4--2.1 MeV/c{sup 2} the upper limits on cross sections obtained from the present data are significantly less than the previously reported cross sections.
Date: December 31, 1995
Creator: Ahmad, I.; Back, B. B. & Austin, S. M.
Object Type: Article
System: The UNT Digital Library
The positron peak puzzle - recent results from APEX (open access)

The positron peak puzzle - recent results from APEX

Results are presented from a new experiment, APEX, designed to study the previously reported sharp lines in sum-energy spectra of positrons and electrons produced in collisions of very heavy ions. Data have been collected for {sup 238}U+{sup 181}Ta and {sup 238}U+{sup 232}Th. No evidence is found for narrow structures similar to those previously reported. For the specific case of the isolated decay of a neutral particle of mass 1.4-2.1 MeV/c{sup 2}, the upper limits on cross sections obtained are significantly less than previously reported. Data are also presented for internal pair conversion in {sup 206}Pb. These results are used to set limits for the possible contribution to the pair yield of a 1780 keV transition in {sup 238}U observed in heavy-ion gamma-ray coincidence measurements.
Date: December 31, 1995
Creator: Ahmad, I.; Back, B.B. & Kutschera, W.
Object Type: Article
System: The UNT Digital Library
Ash and pulverized coal deposition in combustors and gasifiers. Quarterly technical progress report, July 1--September 30, 1995 (open access)

Ash and pulverized coal deposition in combustors and gasifiers. Quarterly technical progress report, July 1--September 30, 1995

During this quarter, further progress has been made in accomplishing the objectives of the project. The computational model for simulating particle motions in turbulent flows has been further developed. The model was applied to the analysis of particle transport and deposition processes in a circular duct and in a plane recirculating region. A model for evaluating particle deposition rate in the presence of gravitational and electrical forces in turbulent flows formulated. Results concerning the deposition velocity of particles under various conditions were obtained. It is shown that the model predictions are in good agreement with the available experimental and digital simulation data. Experimental study of glass fiber transport and deposition rate is also being planned.
Date: December 31, 1995
Creator: Ahmadi, G.
Object Type: Report
System: The UNT Digital Library
Thermal diffusivity imaging of continuous fiber ceramic composite materials and components (open access)

Thermal diffusivity imaging of continuous fiber ceramic composite materials and components

Continuous-fiber ceramic matrix composites (CFCCs) are currently being developed for various high-temperature applications, including use in advanced turbine engines. In such composites, the condition of the interfaces between the fibers and matrix or between laminae in a two-dimensional weave lay-up are critical to the mechanical and thermal behavior of the component. A nondestructive evaluation method that could be used to assess the interface condition and/or detect other `defects` has been developed at Argonne National Laboratory (ANL) and uses infrared thermal imaging to provide `single-shot` full- field quantitative measurement of the distribution of thermal diffusivity in large components. By applying digital filtering, interpolation, and least-squares-estimation techniques for noise reduction, shorter acquisition and analysis times have been achieved with submillimeter spatial resolution for materials with a wide range of `thermal thicknesses`. The system at ANL has been used to examine the effects of thermal shock, oxidation treatment, density variations, and variations in fiber coating in a full array of test specimens. In addition, actual subscale CFCC components of nonplanar geometries have been inspected for manufacturing-induced variations in thermal properties.
Date: December 31, 1995
Creator: Ahuja, S.; Ellingson, W.A.; Steckenrider, J.S. & King, S.
Object Type: Article
System: The UNT Digital Library
Analysis of stray radiation produced by the advanced light source (1.9 GeV synchrotron radiation source) at Lawrence Berkeley Laboratory (open access)

Analysis of stray radiation produced by the advanced light source (1.9 GeV synchrotron radiation source) at Lawrence Berkeley Laboratory

The yearly environmental dose equivalent likely to result at the closest site boundary from the Advanced Light Source was determined by generating multiple linear regressions. The independent variables comprised quantified accelerator operating parameters and measurements from synchronized, in-close (outside shielding prior to significant atmospheric scattering), state-of-the-art neutron remmeters and photon G-M tubes. Neutron regression models were more successful than photon models due to lower relative background radiation and redundant detectors at the site boundary. As expected, Storage Ring Beam Fill and Beam Crashes produced radiation at a higher rate than gradual Beam Decay; however, only the latter did not include zero in its 95% confidence interval. By summing for all three accelerator operating modes, a combined yearly DE of 4.3 mRem/yr with a 90% CI of (0.04-8.63) was obtained. These results fall below the DOE reporting level of 10 mRem/yr and suggest repeating the study with improved experimental conditions.
Date: December 31, 1995
Creator: Ajemian, R. C.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Fischer-tropsch synthesis in supercritical fluids. Quarterly technical progress report, October 1, 1994--December 21, 1994 (open access)

Fischer-tropsch synthesis in supercritical fluids. Quarterly technical progress report, October 1, 1994--December 21, 1994

Progress reports are presented for the following two tasks: (1) diffusion coefficients of F-T products in supercritical fluids; and (2) Fischer-Tropsch reaction related studies. The objectives for this quarter for task 1 were to measure molecular diffusion coefficients and effective diffusivities at the same conditions. The objectives for task 2 were to conduct two additional tests with the Ruhrchemie catalyst and a catalyst synthesized in our laboratory under supercritical conditions.
Date: January 31, 1995
Creator: Akgerman, A. & Bukur, D.B.
Object Type: Report
System: The UNT Digital Library
A flow injection trace gas analyzer for on-site determination of organoarsenicals (open access)

A flow injection trace gas analyzer for on-site determination of organoarsenicals

Lewisite was developed during World War I as a chemical warfare agent. Several countries produced large quantities of the agent before, during and after World War II. The Chemical Weapons Convention treaty, recently signed, requires the destruction of Lewisite. In implementing the Chemical Weapons Convention treaty, it will be necessary to monitor the facilities at which various chemical agents including Lewisite may be stored for compliance with the agreement. The inspection procedures must meet stringent standards for safety, quality assurance and accountability. In preparing for these inspections a technology gap has been identified in the ability to detect and monitor for the presence of Lewisite in ambient air, particularly in the facilities where chemical warfare agents are stored. A method and an apparatus for determining the concentration of Lewisite in the ambient atmosphere are described. The apparatus includes a mechanism for separating and collecting a Lewisite sample from the atmosphere, a mechanism for converting the collected Lewisite to an arsenite ion solution sample, and a mechanism for electrochemically detecting the converted arsenite ions in the sample, whereby the amount of arsenite ions detected is proportional to the concentration of Lewisite in the atmosphere.
Date: December 31, 1995
Creator: Aldstadt, J.H. III
Object Type: Patent
System: The UNT Digital Library
Possible use of the AGS linac for proton therapy (open access)

Possible use of the AGS linac for proton therapy

The BNL 200 MeV linac presently provides beam for the AGS high energy physics program and for isotope production at the Brookhaven Linac Isotope Producer (BLIP) facility. There is now a proposal to develop a proton therapy facility which would also use the linac beam. Approximately 1% of the current in each linac beam pulse would be diverted from BLIP, down an existing transport line, to the proposed new facility. This paper focuses on the basic design of the facility, particularly the accelerator issues. The planned transport line layout is presented, along with a description of the energy and intensity control, and beam delivery systems. In the initial phase, we are planning one 360{degrees} vertical gantry and one horizontal treatment room.
Date: December 31, 1995
Creator: Alessi, J. G.; Chanana, A.; Dilmanian, F. A.; Lee, Y. Y.; Raparia, D.; Tuozzolo, J. et al.
Object Type: Article
System: The UNT Digital Library
Method for separating constituents from solution employing a recyclable Lewis acid metal-hydroxy gel (open access)

Method for separating constituents from solution employing a recyclable Lewis acid metal-hydroxy gel

This invention permits radionuclides, heavy metals, and organics to be extracted from solution by scavenging them with an amorphous gel. In the preferred embodiment, a contaminated solution (e.g. from soil washing, decontamination, or groundwater pumping) is transferred to a reaction vessel. The contaminated solution is contacted by the sequestering reagent which might contain for example, aluminate and EDTA anions in a 2.5 M NaOH solution. The pH of the reagent bearing solution is lowered on contact with the contaminated solution, or for example by bubbling carbon dioxide through it, causing an aluminum hydroxide gel to precipitate as the solution drops below the range of 1.8 to 2.5 molar NaOH (less than pH 14). This precipitating gel scavenges waste contaminants as it settles through solution leaving a clean supernatant which is then separated from the gel residue by physical means such as centrifugation, or simple settling. The gel residue containing concentrated contaminants is then redissolved releasing contaminants for separations and processing. This is a critical point: the stabilized gel used in this invention is readily re-dissolved by merely increasing the pH above the gels phase transition to aqueous anions. Thus, concentrated contaminants trapped in the gel can be released for convenient …
Date: December 31, 1995
Creator: Alexander, D. H.
Object Type: Patent
System: The UNT Digital Library
Applications of lasers to the solution of environmental problems (open access)

Applications of lasers to the solution of environmental problems

This presentation will focus on current work in the Ames Laboratory where laser ablation is being used for both analytical sampling and metal surface cleaning. Examples will be presented demonstrating the utility of optical spectroscopy for monitoring laser ablation processes.
Date: December 31, 1995
Creator: Allen, L.; Pang, H.-M. & Edelson, M. C.
Object Type: Article
System: The UNT Digital Library
Mapping site-specific endonuclease binding to DNA by direct imaging with AFM (open access)

Mapping site-specific endonuclease binding to DNA by direct imaging with AFM

Physical mapping of DNA can be accomplished by direct AFM imaging of site specific proteins bound to DNA molecules. Using Gln-111, a mutant of EcoRI endonuclease with a specific affinity for EcoRI sites 1,000 times greater than wild type enzyme but with cleavage rate constants reduced by a factor of 10{sup 4}, the authors demonstrate site-specific mapping by direct AFM imaging. Images are presented showing specific-site binding of Gln-111 to plasmids having either one (pBS{sup +}) or two (pMP{sup 32}) EcoRI sites. Identification of the Gln-111/DNA complex is greatly enhanced by biotinylation of the complex followed by reaction with streptavidin gold prior to imaging. Image enhancement coupled with improvements in the preparation techniques for imaging large DNA molecules, such as lambda DNA (47 kb), has the potential to contribute to direct AFM restriction mapping of cosmid-sized genomic DNAs.
Date: December 31, 1995
Creator: Allison, D. P.; Thundat, T.; Doktycz, M. J.; Kerper, P. S.; Warmack, R. J.; Modrich, P. et al.
Object Type: Article
System: The UNT Digital Library
Geological and petrophysical characterization of the Ferron sandstone for 3-D simulation of a fluvial-deltaic reservoir. [Quarterly progress report], October 1--December 31, 1995 (open access)

Geological and petrophysical characterization of the Ferron sandstone for 3-D simulation of a fluvial-deltaic reservoir. [Quarterly progress report], October 1--December 31, 1995

The objective of this project is to develop a comprehensive, interdisciplinary, and quantitative characterization of a fluvial-deltaic reservoir which will allow realistic inter-well and reservoir-scale modeling to be constructed for improved oil-field development in similar reservoirs world-wide. The geological and petrophysical properties of the Cretaceous Ferron Sandstone in east-central Utah will be quantitatively determined. Both new and existing data will be integrated into a three-dimensional representation of spatial variations in porosity, storativity, and tensorial rock permeability at a scale appropriate for inter-well to regional-scale reservoir simulation. Results could improve reservoir management through proper infill and extension drilling strategies, reduction of economic risks, increased recovery from existing oil fields, and more reliable reserve calculations. Technical progress this quarter is divided into regional stratigraphy, case studies, and technology transfer activities. The Kf-2 contains more and cleaner sand, indicating a more wave-modified environment of deposition. The regional stratigraphy of the Ferron Sandstone outcrop belt from Last Chance Creek to Ferron Creek was described and interpreted. Photomosaics and a database of existing surface and subsurface data are being used to determine the extent and depositional environment of each parasequence, and the nature of the contacts with adjacent rocks or flow units. Detailed geological and …
Date: December 31, 1995
Creator: Allison, M. L.
Object Type: Report
System: The UNT Digital Library
Phosphor Thermometry of Gas Turbine Surfaces (open access)

Phosphor Thermometry of Gas Turbine Surfaces

This paper describes a nondestructive method for thermometry applicable to ceramic surfaces and coatings. To date our primary application has been to turbine engine and air vehicle surfaces. This method makes use of thermally sensitive phosphors many of which, as it turns out, are also ceramics. These materials fluoresce when suitably illuminated by ultraviolet light. The fluorescence intensity and decay time are well-behaved functions of temperature and therefore serve as reliable indicators of the temperature of the substrate to which the fluorescing material is attached. It is a non- contact method in that the light delivery and collection optics can be remotely located. A range of phosphor materials have been tested and any temperature ranging from 8 to 1900 K can be measured by selection of the appropriate phosphor. Turbine blades, vanes, thermal barrier coatings, and panels are examples of surfaces which have been diagnosed to date in either engine or engine-simulation facilities. A variety of coating methods are used, including electron-beam deposition, radio-frequency sputtering, and curing with inorganic binders. This paper summarizes the results to date and status of this technology.
Date: December 31, 1995
Creator: Allison, Steven W.; Beshears, David L.; Cates, Michael R.; Noel, Bruce W. & Turley, W. D.
Object Type: Article
System: The UNT Digital Library
Selecting reasonable future land use scenarios (open access)

Selecting reasonable future land use scenarios

This paper examines a process to help select the most reasonable future land use scenario for hazardous waste and/or low-level radioactive waste disposal sites. The process involves evaluating future land use scenarios ab applying selected criteria currently used by commercial mortgage companies to determine the feasibility of obtaining a loan for purchasing such land. The basis for the process is that only land use activities for which a loan can be obtained well be considered. To examine the process, a low-level radioactive waste site, the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory, is used as an example. The authors suggest that the process is a very precise, comprehensive, and systematic approach for determining reasonable future use of land. Implementing such a process will help enhance the planning, decisionmaking, safe management, and cleanup of present and future disposal facilities.
Date: December 31, 1995
Creator: Allred, W.E. & Smith, R.W.
Object Type: Article
System: The UNT Digital Library
An investigation of factors affecting the performance of laboratory fume hoods (open access)

An investigation of factors affecting the performance of laboratory fume hoods

A `user tracer gas test` was performed on laboratory hoods, with a human subject standing in front of the hood, to assess hood containment ability. The relationship of face velocity and cross draft variables to hood containment ability is investigated. The ability of these variables and other tests, such as smoke challenges or tracer gas tests performed with a manikin at the hood, to predict the results of the user tracer gas test is evaluated. All of the laboratory hoods tested in this study were identical bench top bypass hoods with horizontally sliding sashes. A face velocity traverse, cross draft measurements, a pitot traverse to measure exhaust flow, a smoke test, a manikin tracer gas test, and a user tracer gas test were performed on each hood in several different sash positions. Based on the data collected, face velocity, its distribution and variability, and the magnitude of cross drafts relative to face velocity are important variables in determining hood leakage. `Unblocked` vortices, formed such that no physical barrier exists between the vortex and room air or a person in front of the hood, are identified as important sites of leakage. For the hoods evaluated in this study, unblocked vortices were …
Date: December 31, 1995
Creator: Altemose, B.A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library