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Use Of The Split-Film Sensor To Measure Turbulence In Water Near A Wall, Paul H. Blinco, V. A. Sandborn Jan 1973

Use Of The Split-Film Sensor To Measure Turbulence In Water Near A Wall, Paul H. Blinco, V. A. Sandborn

Symposia on Turbulence in Liquids

Because of its small size and unique design, the 0.15-mm diameter split-film sensor has many significant advantages over the conventional X-configuration hot-film sensor and the yaw-wire technique for measuring turbulence near a wall. Calibration of the split- film sensor indicates that the magnitude and yaw angle of the instantaneous velocity vector is dependent only on the sum and ratio of the sensor outputs, respectively. Results of limited measurements of the longitudinal and vertical turbulence intensities and Reynolds stress for hydraulically smooth, free surface flows are presented. Digital time series of the split-film outputs revealed the following information: (1) the split-film …


Author Index, University Of Missouri--Rolla Jan 1973

Author Index, University Of Missouri--Rolla

Symposia on Turbulence in Liquids

No abstract provided.


Statistical Analysis Of Instantaneous Velocities In Turbulent Flow Of Dilute Viscoelastic Solutions, A. L. Rollin, F. A. Seyer Jan 1973

Statistical Analysis Of Instantaneous Velocities In Turbulent Flow Of Dilute Viscoelastic Solutions, A. L. Rollin, F. A. Seyer

Symposia on Turbulence in Liquids

An experimental study, based on streak photograph determination of instantaneous velocities, was directed at determining the structure of turbulence within the boundary layer and core regions of circular pipes. The measurements lend support to the ejection phenomenon as the mechanism controlling drag reduction.

A correlation factor, defined as the ratio of the observed number of positive instantaneous radial velocities, to the observed number of negative instantaneous radial velocities, suggests acceleration in the radial direction as the elements of fluid move through the sublayer. The correlation factor also provides information about the thickening of the boundary layer for drag reducers relative …


Flow Visualization Studies On Drag-Reducing Turbulent Flows, R. H. J. Sellin Jan 1973

Flow Visualization Studies On Drag-Reducing Turbulent Flows, R. H. J. Sellin

Symposia on Turbulence in Liquids

Flow visualisation studies in a square duct of internal dimensions 44.5 x 44.5 mm are reported. The flow marker is a stream of opaque white dye, released from a downstream facing stationary tube, and it is photographed through the plexiglass wall of the duct. The point of dye release can be traversed in a direction perpendicular to the duct wall and three locations are investigated, two in the core of the flow and one in the near- wall region. By using Is exposure times photographs are obtained of a dye dispersion cone and the cone angle is measured and related …


Experiments On The Structure Of Turbulence In Fully Developed Pipe Flow, T. R. Heidrick, S. Banerjee, R. S. Azad Jan 1973

Experiments On The Structure Of Turbulence In Fully Developed Pipe Flow, T. R. Heidrick, S. Banerjee, R. S. Azad

Symposia on Turbulence in Liquids

This paper describes a series of two-point measurements in fully developed pipe flow. Measurements of the phase shifts between the Fourier components of the axial velocity fluctuations at two points were made with three different orientations of the two points. In all cases the two points were close enough together that the turbulent structure remained essentially "frozen" while passing between the sensors. The phase velocities, C1(f), and inclinations, α(f) (defined previously by Heidrick et al. (8)), of each frequency component, f, were determined from these measurements.

In general, the Fourier components are inclined to the wall - the …


Measurements Of Pulsating Turbulent Water Flow In A Tube, S.-Z. Lu, R. J. Nunge, F. F. Erian, M. Mohajery Jan 1973

Measurements Of Pulsating Turbulent Water Flow In A Tube, S.-Z. Lu, R. J. Nunge, F. F. Erian, M. Mohajery

Symposia on Turbulence in Liquids

The experimental method associated with obtaining meaningful information from the hot-film anemometer signals in fully developed pulsating turbulent flow where the pulsations are sinusoidal in time is discussed. The results of a number of experiments in water reveal the nature of the longtime and short-time average velocity and pressure. Velocity measurements between 0.95 radii and the centerline demonstrate that the long-time average velocity distribution is coincident with that for steady turbulent flow at the same Reynolds number. Also, no significant differences between the longtime average axial pressure drop in the pulsating and steady flows were noted, although this requires further …


Investigation Of Roof Shales In Illinois Coal Mines, Peter J. Conroy Jan 1973

Investigation Of Roof Shales In Illinois Coal Mines, Peter J. Conroy

Doctoral Dissertations

"This thesis describes an investigation of the relationships among the composition, physical properties and the performance of roof shales in Illinois coal mines. The study included cataloging the physical and mineralogical properties of typical roof shales, determining the interrelationships of the properties and defining the factors in the rock which effect deterioration. From the results, a classification system has been developed which may provide a means for evaluating coal mine roof stability.

A coring apparatus was developed for obtaining in situ samples from mine roofs. Five coal mines with varying geologic and roof conditions were sampled. Precautions were taken to …


Letters To The Editor, J. T. Mason, Orrin K. Crosser, Robert D. Gunn, C. Judson King Jan 1973

Letters To The Editor, J. T. Mason, Orrin K. Crosser, Robert D. Gunn, C. Judson King

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.


A Study Of Medium And High Internal Phase Ratio Water/Polymer Emulsions, Kenneth J. Lissant, Kenneth G. Mayhan Jan 1973

A Study Of Medium And High Internal Phase Ratio Water/Polymer Emulsions, Kenneth J. Lissant, Kenneth G. Mayhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Medium and high internal phase ratio water/polymer emulsions were studied utilizing scanning electron microscope techniques. Results are reported for the geometry and distribution of droplets for water/polymer ratios from 1 1 to 9 1. Electron micrographs confirm those models which predicts polyhedral droplet formation at high internal phase ratios. © 1973.


Polymers From The Hydrolysis Of Tetraethoxysilane, B. W. Peace, Kenneth G. Mayhan, J. F. Montle Jan 1973

Polymers From The Hydrolysis Of Tetraethoxysilane, B. W. Peace, Kenneth G. Mayhan, J. F. Montle

Chemical and Biochemical Engineering Faculty Research & Creative Works

The hydrolysis of tetraethoxysilane was studied under various solvent and temperature conditions. A method was developed by which reaction rates can be measured even in the presence of alcohols other than ethanol. The structures of the resulting polymers were dependent upon the reaction conditions employed, those formed at high temperature being highly condensed materials. © 1973.


The Des Moines Rapids: A History Of Its Adverse Effects On Mississippi River Traffic And Its Use As A Source Of Water Power To 1860, Donald L. Enders Jan 1973

The Des Moines Rapids: A History Of Its Adverse Effects On Mississippi River Traffic And Its Use As A Source Of Water Power To 1860, Donald L. Enders

Theses and Dissertations

During the 19th Century, the Mississippi River was the chief commercial highway in the United States. But for two impediments, the Upper and Lower (Des Moines) Rapids, its entire course of 2400 miles would have offered an untroubled thoroughfare to watercraft.

The federal government, as well as private concerns, attempted throughout the better part of that century to alleviate the river of its barriers and to develop its rapids as a source of power. Those attempts were disappointingly unsuccessful, however, and not until the advent of the 20th Century, when the nation had matured both economically and technologically, was the …


A Geographic Study Of Stone Houses In Selected Utah Communities, Barry M. Roth Jan 1973

A Geographic Study Of Stone Houses In Selected Utah Communities, Barry M. Roth

Theses and Dissertations

This thesis will investigate the spatial location of stone houses and the areal differentiation of several characteristics of stone houses in selected communities. Some differences in cultural and historical factors and in types of building stone, quarries and quarrying techniques will be studied. The thesis will also investigate why stone houses are still in existence and things that owners, residents, and others like and dislike about them.


The Effects Of Ionizing Radiation On Gallium Arsenide Phosphide Metal-Insulator-Semiconductor Structures, Gordon James Kuhlmann Jan 1973

The Effects Of Ionizing Radiation On Gallium Arsenide Phosphide Metal-Insulator-Semiconductor Structures, Gordon James Kuhlmann

Electrical and Computer Engineering ETDs

MIS capacitors were fabricated on n-type GaAs 0.5 p 0.5 using a thermally grown chromium-doped insulator and chromium gate electrode. The fabrication procedures which lead to stable devices are described. The nature of the composite insulator, as well as that of a disordered layer of GaAs 0.5 P 0.5 underneath the insulator are discussed and related to observed electrical characteristics.

Flatband voltages for the capacitors subsequent to device fabrication ranged from -2.5 to -5 volts, corresponding to surface charge densities of 3.1 x 10 11 cm-2 to 4.3 x 10 11 cm-2. Fast interface state densities at flatband varied from …


A Technique For Improving Material Balance Accuracy In Reservoir Simulation Models, A. R. Merchant, Marion D. Arnold, A. Herbert Harvey Jan 1973

A Technique For Improving Material Balance Accuracy In Reservoir Simulation Models, A. R. Merchant, Marion D. Arnold, A. Herbert Harvey

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

One criterion for determining the precision of pressures calculated by a simulation model is the accuracy of the material balance. A high degree of precision in the calculated pressures is a necessary but not sufficient condition for elimination of significant errors in the prediction of fluid migration in the reservoir. A new procedure, called error matrix technique, has been developed for reduction of material balance errors. This reduction is accomplished by adjusting potential gradients at every grid point in the simulation model so that the material balance is accurately maintained. Performance of a hypothetical oil reservoir was simulated both by …


Transmission Measurements Through Liquids In A White Cell, David Earl Hurley Jan 1973

Transmission Measurements Through Liquids In A White Cell, David Earl Hurley

Masters Theses

"The suitability of using the White cell for determining the extinction coefficient of liquids was examined by measuring the attenuation of electromagnetic radiation, in the visible part of the spectrum, through distilled water. The analysis of the transmittance measurements through liquids in a White cell does not provide a sufficient number of independent equations to solve directly for the extinction coefficient. Reasonable estimates however can be made by employing a correction which accounts for changes in the mirror reflectance due to a liquid-mirror interface.

The reduction in the transmittance of distilled water due to an oil film was studied for …


A Study Of The Splash-Plate Tower Concept, A Biological Wastewater Treatment Process, Robert Joseph Millman Jan 1973

A Study Of The Splash-Plate Tower Concept, A Biological Wastewater Treatment Process, Robert Joseph Millman

Masters Theses

"Different modifications and newer methods of treatment which utilize the basic trickling filter concepts, such as the Bio-Disc process, have been developed to increase the efficiency of wastewater treatment. The purpose of this investigation was to develop and evaluate a newer such method called the splash plate concept.

The splash-plate concept utilizes a series of circular plates mounted horizontally on a vertical axis. This allows the wastewater being treated to travel over one plate to the edge and splash down to the next lower plate and so on throughout the tower. A total of four units were operated at different …


0057: Addison Moffat Scott Papers, 1873-1939, Marshall University Special Collections Jan 1973

0057: Addison Moffat Scott Papers, 1873-1939, Marshall University Special Collections

Guides to Manuscript Collections

Charleston, West Virginia, engineer. Papers relate to the construction and improvement of navigation on the Great Kanawha River with the first system of locks and dams. Includes bid proposals and specifications for the construction of locks, dams, and buildings.


Formation And Densification Of Cadmium Manganese Ferrite, B. W. Jong, P. D. Ownby Jan 1973

Formation And Densification Of Cadmium Manganese Ferrite, B. W. Jong, P. D. Ownby

Materials Science and Engineering Faculty Research & Creative Works

Formation of Ni-ferrite, Mn-ferrite, NiZn-ferrite, Zn-ferrite and Mg-ferrite have been investigated using X-ray diffraction analysis. Jander's diffusion equation described the data from these investigations over a portion of the temperature ranges studied. However, the reaction mechanisms and sequences involved in the formation of mixed ferrites have not been well defined in the literature. The purposes of this investigation were: ( 1) To further the understanding of the formation of CdMnferrite by studying first the kinetics of the formation of Cd-ferrite and Cd-manganite, which provides a basis for understanding the details of the mixed CdMn-ferrite reaction and to obtain the optimum …


Oxidation Of Tetragonal Pbo In Air, Charles A. Sorrell Jan 1973

Oxidation Of Tetragonal Pbo In Air, Charles A. Sorrell

Materials Science and Engineering Faculty Research & Creative Works

Isothermal oxidation of tetragonal PbO in air produced multiphase assemblages with apparent equilibrium compositions which varied linearly with temperature from PbO1.548 at 286°C to PbO1.333 at 351°C. Oxidation at each temperature was relatively rapid to PbO1.40 and very slow from PbO1.40 to apparent equilibrium values. Pseudocubic PbO1+x, with compositions between PbO1.41 and PbO1.57, was indexed on a cubic unit cell at the lower O/Pb ratios and on a tetragonal unit cell at the higher ratios. Linear changes in lattice parameters and deviation from cubic symmetry accompanied reversible oxidation and reduction of the phase. Pseudocubic PbO1+x was reduced irreversibly to Pb3O4 …


Stratigraphic Relations Of Members Of The Needles Range Formation At Type Localities In Southwestern Utah, M. G. Best, R. T. Shuey, C. F. Caskey, S. Kerry Grant Jan 1973

Stratigraphic Relations Of Members Of The Needles Range Formation At Type Localities In Southwestern Utah, M. G. Best, R. T. Shuey, C. F. Caskey, S. Kerry Grant

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Needles Range Formation is one of the most extensive of the middle Tertiary ash-flow sheets in the Great Basin of Nevada and western Utah. The original definition of the formation by Mackin (1960) named two members and mentioned three type localities. Our recent studies have shown that this published information now requires revision. To provide a firm basis for stratigraphic studies of the Needles Range Formation, this paper presents geologic maps, measured sections, and paleomagnetic data for three type localities in southwestern Utah. These include the northern Needles Range and Wah Wah Springs localities previously mentioned by Mackin, plus …


Measurement Of Unsteady Flows In Mercury With Hot-Film Anemometers, Charles A. Sleicher, G. B. Lim Jan 1973

Measurement Of Unsteady Flows In Mercury With Hot-Film Anemometers, Charles A. Sleicher, G. B. Lim

Symposia on Turbulence in Liquids

The difficulties in making turbulence measurements in liquid metals are discussed briefly. Attention is then focused on the problem of frequency response attenuation of hot-film anemometers by the thermal capacity of the thermal boundary layer near cylindrical sensors. A solution is given to the problem of heat transfer from an infinite cylinder normal to the potential flow of a fluid with a small sinusoidal velocity component. Application of the results to anemometer measurements is discussed. Some preliminary experiments on dynamic calibration are reported, and they are in reasonable agreement with the theory for Peclet numbers less than one.


Turbulence Measurements In Submerged Water Jets By Electromagnetic Induction Anemometry, Walter C. Mih Jan 1973

Turbulence Measurements In Submerged Water Jets By Electromagnetic Induction Anemometry, Walter C. Mih

Symposia on Turbulence in Liquids

This paper describes the measurement and data analysis of the turbulence in a two-dimensional water jet discharging from a thin slot into a large body of stationary water having the same width as the slot. Tap water without additives was used as the flow medium. The electromagnetic induction method (commonly known as magnetohydrodynamics, or the MHD method) was used to sense the fluctuation velocities in the diffusion zone of the jet. A DC magnet was placed outside the flow field with the magnetic flux density of 885 Gauss perpendicular to the plane of homogeneity of the two-dimensional flow field. A …


Hydrogen-Bubble Flow-Visualization: Limitations In Drag Reducing Polymer Solutions, George L. Donohue Jan 1973

Hydrogen-Bubble Flow-Visualization: Limitations In Drag Reducing Polymer Solutions, George L. Donohue

Symposia on Turbulence in Liquids

Hydrogen-bubble flow-visualization experiments have demonstrated that distinct bubble pulses cannot be obtained in water solutions of polyacrylamide of high enough molecular weight to cause drag reduction at low shear stresses. Good bubble pulses were obtained in poly(ethylene oxide) and in surfactant solutions, but they did not cause drag reduction at feasible shear stresses.


Measurement Of Reynolds Stress And Turbulence In Dilute Polymer Solution By Laser Velocimeter, Samuel E. Logan Jan 1973

Measurement Of Reynolds Stress And Turbulence In Dilute Polymer Solution By Laser Velocimeter, Samuel E. Logan

Symposia on Turbulence in Liquids

Measurements of Reynolds stress and axial and transverse turbulence intensities have been made in turbulent pipe flow of a dilute solution of high molecular weight polymer and compared to measurements made with pure water. A laser velocimeter capable of measuring these turbulence parameters has been developed and utilized.

Axial turbulence intensities are consistent in behavior and magnitude with previous polymer results and the measurements of transverse intensity and Reynolds stress are similarly well behaved and self consistent. Sublayer thickening in drag reducing polymer solution is observed, in consonance with earlier work. New results include demonstration that the turbulent shearing stress …


Conference Proceedings Of The 3rd Biennial Symposium On Turbulence In Liquids, University Of Missouri--Rolla Jan 1973

Conference Proceedings Of The 3rd Biennial Symposium On Turbulence In Liquids, University Of Missouri--Rolla

Symposia on Turbulence in Liquids

The Third Biennial Symposium on Turbulence in Liquids showed further progress in the investigator's ability to measure turbulence parameters and in the general understanding of turbulence. The most impressive advances in measurement seemed to be the ability to measure deeper into the turbulent boundary layer in order to obtain profiles over the entire turbulence production region and the rapid development of conditioned-sampling techniques for studying hypotheses for mechanisms.


Ldv Measurements In Turbulent Free Convection, R. J. Adrian Jan 1973

Ldv Measurements In Turbulent Free Convection, R. J. Adrian

Symposia on Turbulence in Liquids

The design and performance of a laser Doppler velocimeter (LDV) used in a turbulent water-overice convection experiment are described. The LDV was operated in a reference beam mode with an ultrasonic diffraction grating shifting the reference beam frequency to provide bipolar sensing of the vertical velocity, and a phase-locked loop was used to demodulate the Doppler frequency information. The maximum observed velocities in the experiment were ± 1 mm/sec, and the accuracy of instantaneous measurement was limited by Brownian motion and laser line width to ± .04 mm/sec for a 2 Hz frequency response. The practical difficulties encountered in this …


Features Of A Separating Turbulent Boundary Layer As Revealed By Laser And Hot-Film Anemometry, R. L. Simpson, J. H. Strickland, P. W. Barr Jan 1973

Features Of A Separating Turbulent Boundary Layer As Revealed By Laser And Hot-Film Anemometry, R. L. Simpson, J. H. Strickland, P. W. Barr

Symposia on Turbulence in Liquids

Experiments have been performed to determine the fundamental nature of boundary layer separation produced by an adverse pressure gradient. Measurements upstream and downstream of the separation zone have been made utilizing laser and hot-film anemometry techniques.

A completely mobile backscattering laser anemometer was developed. This alone is a significant development because of the relatively long focal lengths required for measurements in a 36" wide wind tunnel. Signal processing was achieved by a digital signal sampling and storage system. Both mean and fluctuating velocities in both the unseparated and separated flow regions were measured. Experimental results are in fairly good agreement …


Turbulence Measurements With A Sampling Laser-Doppler Velocimeter, P. D. Iten Jan 1973

Turbulence Measurements With A Sampling Laser-Doppler Velocimeter, P. D. Iten

Symposia on Turbulence in Liquids

A novel sampling signal processor overcomes the difficulties encountered with frequency trackers in the investigation of unseeded highly turbulent flows. This sampling system consists essentially of a swept filter, e.g. a standard RF-spectrum analyzer, a digital data memory and a storage oscilloscope. It is able to determine first-order statistical averages of turbulent flows with high fluctuation frequencies and amplitudes even at very low scattering particle concentrations. Since the velocity samples are not statistically independent of the velocity, the sampled velocity data has to be corrected in order to obtain unbiased statistical averages. A theoretical analysis and experimental investigations of the …


Analysis Of A Laser Correlation Anemometer, L. Lading Jan 1973

Analysis Of A Laser Correlation Anemometer, L. Lading

Symposia on Turbulence in Liquids

An analysis of a laser anemometer is given. The anemometer is based on the cross correlation of the random signals generated by the scattering from -- and/or extinction of -- two parallel laser beams. The basic set-up is compared with the laser Doppler anemometer.

It is shown that the correlation function exhibits a broadening and generally also a skewness - equivalent to the broadening (transit time) and skewness (velocity gradients) of the Doppler spectrum.

The conditions for "instantaneous point" measurements are derived.

It is shown how a particle (drop/bubble) size versus particle velocity spectrum can be obtained by appropriate electronic …


Design Considerations For A Laser Doppler Velocimeter, Leroy M. Fingerson Jan 1973

Design Considerations For A Laser Doppler Velocimeter, Leroy M. Fingerson

Symposia on Turbulence in Liquids

In optimizing an instrument design, it is important to differentiate between the theoretical limitations of the technique and apparent limitations that can be reduced or eliminated by design. In the laser-Doppler anemometer, the theoretical limits are associated with the fact that particle velocity is the measurement rather than fluid velocity. The accuracy and speed of the particle velocity measurements do not appear to have theoretical limitations. Therefore, instrument design must concentrate on improving the measurement of particle velocity.

A complete system has been designed to optimize accuracy, speed, convenience, and flexibility in measuring particle velocity. The problems inherent in transferring …