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Propeller section aerodynamic characteristics as determined by measuring the section surface pressures on an NACA 10-(3)(08)-03 propeller under operating conditions

Description: Report presenting a wind-tunnel investigation to determine propeller section aerodynamic characteristics by measuring surface pressure distribution on the airfoil sections of a rotating propeller. The pressures were measured at nine radial sections of the NACA 10-(3)(08)-03 two-blade propeller. Results regarding sectional critical Mach number, and aerodynamic coefficients are also presented.
Date: November 8, 1950
Creator: Evans, Albert J.
Partner: UNT Libraries Government Documents Department

Tests of Four Full-Scale Propellers to Determine the Effect of Trailing-Edge Extensions on Propeller Aerodynamic Characteristics

Description: Propellers with trailing-edge extensions were studied to determine aerodynamic characteristics. Trailing-edge extension increased power absorbed by propeller with little loss in efficiency. Power coefficient for maximum efficiency was greater for 20% camber type extension than for 20% straight type extension over range of advance ratio of 1.0 to 2.5 although camber type was less efficient. Efficiency was about the same for cruising and high-speed at a high power coefficient for propeller with extension.
Date: July 1945
Creator: Maynard, Julian D. & Evans, Albert J.
Partner: UNT Libraries Government Documents Department

Kinetics of Reactions of Substituted Group VI B Metal Carbonyls with Phosphites

Description: The problem with which this investigation is concerned is twofold. The initial part of the problem was to prepare a non-sterically demanding bidentate phosphine ligand, 1,2-bis-(Phosphino)ethane, (P-en), and to determine the kinetics of (P-en)Mo(CO)4 with phosphites via spectrophotometric methods in an attempt to determine if steric effects are directing the type of mechanism followed.
Date: August 1972
Creator: Rettenmaier, Albert J.
Partner: UNT Libraries

A wind-tunnel investigation of the aerodynamic characteristics of a full-scale sweptback propeller and two related straight propellers

Description: Report presenting an investigation of an NACA 10-(1.7)(062)-057-27 two-blade swept propeller was conducted int he 16-foot high-speed tunnel over a range of blade-angle settings. Two related straight propellers were also tested over the same operating range as the swept propeller. Results regarding envelope efficiency, effect of compressibility on maximum efficiency, effect of sweep on power coefficient, constant-power propeller operation, and effect of sweep on propeller-blade loading are provided.
Date: January 4, 1951
Creator: Evans, Albert J. & Liner, George
Partner: UNT Libraries Government Documents Department

A wind-tunnel investigation of the aerodynamic characteristics of a full-scale supersonic-type three-blade propeller at Mach numbers to 0.96

Description: From Summary: "An investigation of the characteristics of a full-scale supersonic-type propeller has been made in the Langley 16-foot transonic tunnel with the 6000-horsepower propeller dynamometer. The tests covered a range of blade angles from 20.2 degrees to 60.2 degrees at forward Mach numbers up to 0.96. The results showed that envelope efficiency at an advance ratio of 2.8 decreased from 86 percent to 72 percent when the forward Mach number was increased from 0.70 to 0.96."
Date: May 18, 1953
Creator: Evans, Albert J. & Liner, George
Partner: UNT Libraries Government Documents Department

The zero-lift drag of a slender body of revolution (NACA RM-10 research model) as determined from tests in several wind tunnels and in flight at supersonic speeds

Description: From Summary: "The results of tests of a slender body of revolution designated the NACA rm-10 have been compiled from various NACA test facilities. Zero-lift drag data are presented for a Reynolds number range from about 1 x 10(6) to 40 x 10(6) from several wind tunnels and from about 12 x 10(6) to 140 x 10(6) from free-flight tests. The Mach numbers covered include 1.5 to 2.4 for the wind-tunnel data and 0.85 to 2.5 for the flight results. The wind tunnel models were tested with and without 60 degree sweptback stabilizing fins and the flight models were tested with stabilizing fins."
Date: April 16, 1953
Creator: Evans, Albert J.
Partner: UNT Libraries Government Documents Department

The zero-lift drag of a slender body of revolution (NACA RM-10 research model) as determined from tests in several wind tunnels and in flight at supersonic speeds

Description: Presents zero-lift drag data of an NACA RM-10 slender body of revolution with and without stabilizing fins attached. The results from several wind tunnels and in flight are compared. The results cover a Reynolds number range from about 1 time 10 to the 6th power to 40 times 10 to the 6th power for the flight models. The Mach numbers covered include 1.5 to 2.4 in the wind tunnels and 0.85 to 2.5 in flight.
Date: April 1953
Creator: Evans, Albert J.
Partner: UNT Libraries Government Documents Department

Pressure distributions on the blade sections of the NACA 10-(5)(066)-03 propeller under operating conditions

Description: A report in a series of five that present unanalyzed pressure data obtained in tests of five full-scale propellers with NACA 16-series blade sections. Pressure distributions on the blade sections were measured under operating conditions to determine the aerodynamic characteristics of each blade section. This particular report presents information for eight radial stations of the NACA 10-(5)(066)-03 propeller.
Date: April 18, 1950
Creator: Evans, Albert J. & Luchuk, Wallace
Partner: UNT Libraries Government Documents Department

Preliminary investigation to determine propeller section characteristics by measuring the pressure distribution on an NACA 10-(3)(08)-03 propeller under operating conditions

Description: From Summary: "An investigation has been made in the Langley 16-foot high-speed tunnel to determine the propeller-section characteristics by measuring the pressure distribution on the airfoil sections of a rotating propeller. The pressures were measured at nine radial stations on an NACA 10-(3)(08)-03 design two-blade propeller. This paper presents the results of the pressure measurements in the form of normal-force and moment coefficients and covers a range of nominal angle of attack (simple blade element theory) from 0 degrees to 4 degrees for a section Mach number range of approximately 0.6 to 1.15 for the outboard stations and approximately 0.3 to 0.6 for inboard stations."
Date: July 14, 1948
Creator: Evans, Albert J. & Liner, George
Partner: UNT Libraries Government Documents Department

Preliminary investigation of two full-scale propellers to determine the effect of swept-back blade tips on propeller aerodynamic characteristics

Description: Report presenting an investigation of two 10-foot-diameter three-blade propellers to determine the effect of swept-back blade tips on propeller aerodynamic characteristics. Results regarding the effect of swept-back tips on maximum efficiency and constant-power propeller operation are provided.
Date: May 12, 1947
Creator: Evans, Albert J. & Klunker, E. Bernard
Partner: UNT Libraries Government Documents Department

Final Technical Report, DOE/ER/64323

Description: The DOE SciDAC program funded a team that developed PFLOTRAN, the next-generation (‘peta-scale’) massively parallel, multiphase, multicomponent reactive flow and transport code. These codes are required to improve understanding and risk management of subsurface contaminant migration and geological sequestration of carbon dioxide. The important fate and transport processes occurring in the subsurface span a wide range of spatial and temporal scales, and involve nonlinear interactions among many different chemical constituents. Due to the complexity of this problem, modeling subsurface processes normally requires simplifying assumptions. However, tools of advanced scientific computing that have been used in other areas such as energy and materials research can also help address challenging problems in the environmental and geoscience fields. The overall project was led by Los Alamos National Laboratory and included Argonne, Oak Ridge and Pacific Northwest National Laboratories, in addition to the University of Illinois. This report summarizes the results of the research done at the University of Illinois, which focused on improvements to the underlying physical and computational modeling of certain transport and mixing processes.
Date: June 5, 2013
Creator: Valocchi, Albert J.
Partner: UNT Libraries Government Documents Department

Influence of Wetting and Mass Transfer Properties of Organic Chemical Mixtures in Vadose Zone Materials on Groundwater Contamination by Nonaqueous Phase Liquids

Description: Previous studies have found that organic acids, organic bases, and detergent-like chemicals change surface wettability. The wastewater and NAPL mixtures discharged at the Hanford site contain such chemicals, and their proportions likely change over time due to reaction-facilitated aging. The specific objectives of this work were to (1) determine the effect of organic chemical mixtures on surface wettability, (2) determine the effect of organic chemical mixtures on CCl4 volatilization rates from NAPL, and (3) accurately determine the migration, entrapment, and volatilization of organic chemical mixtures. Five tasks were proposed to achieve the project objectives. These are to (1) prepare representative batches of fresh and aged NAPL-wastewater mixtures, (2) to measure interfacial tension, contact angle, and capillary pressure-saturation profiles for the same mixtures, (3) to measure interphase mass transfer rates for the same mixtures using micromodels, (4) to measure multiphase flow and interphase mass transfer in large flow cell experiments, all using the same mixtures, and (5) to modify the multiphase flow simulator STOMP in order to account for updated P-S and interphase mass transfer relationships, and to simulate the impact of CCl4 in the vadose zone on groundwater contamination. Results and findings from these tasks and summarized in the attached final report.
Date: May 21, 2011
Creator: Werth, Charles J & Albert J Valocchi, Hongkyu Yoon
Partner: UNT Libraries Government Documents Department

Migration of Gas-Liquid Inclusions in KCl and NaCl Single Crystals

Description: Natural salt deposits contain small brine inclusions which can be set into motion by a temperature gradient arising from storage of nuclear wastes in the salt. Inclusions totally filled with liquid move up the temperature gradient, but cavities which are filled partly with liquid and partly by an insoluble gas move in the opposite direction. The velocities of these gas-liquid inclusions are calculated from a model which includes: heat transport in the gas/liquid/solid composite medium; vapor transport of water in the gas bubble as the principal mechanism causing cavity motion; and the effect of molecular and thermal diffusion on transport of salt in the liquid phase. An analytical expression for the inclusion velocity is obtainable with certain simplifications, which include: approximating the cubical cavity in the solid as a spherical hole containing a central gas bubble and an annular shell of liquid; neglecting interface kinetics (i.e., slow dissolution and crystallization steps) and assuming the process to be diffusion-controlled and disregarding fluid motion generated by surface tension gradients at the gas/liquid interface. The theory predicts a change in the migration direction at a critical volume fraction gas in the cavity. For gas fractions greater than this critical value, the theory gives the velocities of migration down the temperature gradient which are in satisfactory agreement with available experimental data.
Date: August 1, 1980
Creator: Olander, Donald R.; Machiels, Albert J. & Muchowski, Eugen
Partner: UNT Libraries Government Documents Department

Investigation of Pore Scale Processes That Affect Soil Vapor Extraction

Description: Dense nonaqueous phase liquid (DNAPL) contamination in the vadose zone is a significant problem at Department of Energy sites. Soil vapor extraction (SVE) is commonly used to remediate DNAPLs from the vadose zone. In most cases, a period of high recovery has been followed by a sustained period of low recovery. This behavior has been attributed to multiple processes including slow interphase mass transfer, retarded vapor phase transport, and diffusion from unswept zones of low permeability. Prior attempts to uncouple and quantify these processes have relied on column experiments, where the effluent concentration was monitored under different conditions in an effort to quantify the contributions from a single process. In real porous media these processes occur simultaneously and are inter-related. Further, the contribution from each of these processes varies at the pore scale and with time. This research aims to determine the pore-scale processes that limit the removal of DNAPL components in heterogeneous porous media during SVE. The specific objectives are to: (1) determine the effect of unswept zones on DNAPL removal during SVE, (2) determine the effect of retarded vapor phase transport on DNAPL removal during SVE, and (3) determine the effect of interphase mass transfer on DNAPL removal during SVE, all as a function of changing moisture and DNAPL content. To fulfill these objectives we propose to use magnetic resonance imaging (MRI) to observe and quantify the location and size of individual pores containing DNAPL, water, and vapor in flow through columns filled with model and natural sediments. Imaging results will be used in conjunction with modeling techniques to develop spatially and temporally dependent constitutive relations that describe the transient distribution of phases inside a column experiment. These constitutive relations will be incorporated into a site-scale transport model to evaluate how the different processes affect SVE performance in ...
Date: June 1, 2001
Creator: Valocchi, Albert J.; Werth, Charles J. & Webb, Andrew G.
Partner: UNT Libraries Government Documents Department

Investigation of Pore Scale Processes That Affect Soil Vapor Extraction

Description: Dense nonaqueous phase liquid (DNAPL) contamination in the vadose zone is a significant problem at Department of Energy sites. Soil vapor extraction (SVE) is commonly used to remediate DNAPLs from the vadose zone. In most cases, a period of high recovery has been followed by a sustained period of low recovery. This behavior has been attributed to multiple processes including slow interphase mass transfer, retarded vapor phase transport, and diffusion from unswept zones of low permeability.
Date: June 1, 2002
Creator: Valocchi, Albert J.; Werth, Charles J. & Webb, Andrew G.
Partner: UNT Libraries Government Documents Department

Investigation of Pore Scale Processes That Affect Soil Vapor Extraction

Description: Dense nonaqueous phase liquid (DNAPL) contamination in the vadose zone is a significant problem at Department of Energy sites. Soil vapor extraction (SVE) is commonly used to remediate DNAPLs from the vadose zone. In most cases, a period of high recovery has been followed by a sustained period of low recovery. This behavior has been attributed to multiple processes including slow interphase mass transfer, retarded vapor phase transport, and diffusion from unswept zones of low permeability. Prior attempts to uncouple and quantify these processes have relied on column experiments, where the effluent concentration was monitored under different conditions in an effort to quantify the contributions from a single process. In real porous media these processes occur simultaneously and are inter-related. Further, the contribution from each of these processes varies at the pore scale and with time. This research aims to determine the pore-scale processes that limit the removal of DNAPL components in heterogeneous porous media during SVE. The specific objectives are to: (1) determine the effect of unswept zones on DNAPL removal during SVE, (2) determine the effect of retarded vapor phase transport on DNAPL removal during SVE, and (3) determine the effect of interphase mass transfer on DNAPL removal during SVE, all as a function of changing moisture and DNAPL content. To fulfill these objectives we propose to use magnetic resonance imaging (MRI) to observe and quantify the location and size of individual pores containing DNAPL, water, and vapor in flow through columns filled with model and natural sediments. Imaging results will be used in conjunction with modeling techniques to develop spatially and temporally dependent constitutive relations that describe the transient distribution of phases inside a column experiment. This work will lead to improved models that will allow decision makers to better assess the risk associated with vadose zone ...
Date: June 1, 2003
Creator: Valocchi, Albert J.; Werth, Charles J. & Webb, Andrew G.
Partner: UNT Libraries Government Documents Department

Investigation of Pore Scale Processes That Affect Soil Vapor Extraction

Description: Dense nonaqueous phase liquid (DNAPL) contamination in the vadose zone is a significant problem at Department of Energy sites. Soil vapor extraction (SVE) is commonly used to remediate DNAPLs from the vadose zone. In most cases, a period of high recovery has been followed by a sustained period of low recovery. This behavior has been attributed to multiple processes including slow interphase mass transfer, retarded vapor phase transport, and diffusion from unswept zones of low permeability. Prior attempts to uncouple and quantify these processes have relied on column experiments, where the effluent concentration was monitored under different conditions in an effort to quantify the contributions from a single process. In real porous media these processes occur simultaneously and are inter-related. Further, the contribution from each of these processes varies at the pore scale and with time. This research aims to determine the pore-scale processes that limit the removal of DNAPL components in heterogeneous porous media during SVE. The specific objectives are to: (1) determine the effect of unswept zones on DNAPL removal during SVE, (2) determine the effect of retarded vapor phase transport on DNAPL removal during SVE, and (3) determine the effect of interphase mass transfer on DNAPL removal during SVE, all as a function of changing moisture and DNAPL content. To fulfill these objectives we propose to use magnetic resonance imaging (MRI) to observe and quantify the location and size of individual pores containing DNAPL, water, and vapor in flow through columns filled with model and natural sediments. Imaging results will be used in conjunction with modeling techniques to develop spatially and temporally dependent constitutive relations that describe the transient distribution of phases inside a column experiment. This work will lead to improved models that will allow decision makers to better assess the risk associated with vadose zone ...
Date: June 24, 2004
Creator: Valocchi, Albert J.; Werth, Charles J. & Webb, Andrew G.
Partner: UNT Libraries Government Documents Department

Final technical report for Interagency Agreement No. DE-AI02-98ER62683: Development of a functional genomics approach to use radiation-induced changes in gene expression to monitor for low dose and low dose-rate exposures

Description: Microarray analysis and other molecular biology techniques were used to investigate the regulation of gene expression following ionizing radiation exposure.
Date: October 23, 2001
Creator: Albert J. Fornace, Jr.
Partner: UNT Libraries Government Documents Department

A study of sediment motion and bottom boundary layer dynamics over the Middle Atlantic Bight shelf and upper slope. Final report

Description: This report summarizes research on circulation and particle dynamics over the Middle Atlantic Bight shelf and upper slope. It includes an overview of the field experiments conducted in the waters off North Carolina, and gives the principal results from these experiments.
Date: February 14, 2001
Creator: Churchill, James H. & Williams, Albert J.
Partner: UNT Libraries Government Documents Department