Engineering Commons^™

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 …

Electrochemical Reduction Of Molybdenum(Vi) Compounds In Molten Lithium Chloride-Potassium Chloride Eutectic, Branko N. Popov, H. A. Laitinen

Faculty Publications

Molybdenum (VI) oxide reacts with molten LiCl-KCl eutectic at 450° to form MoO₂CI₂, which probably is present as an anion MoO₂Cl₄⁼, and pyromolybdate, Mo₂O₇⁼. Both of these species are electrochemically reduced to MoO₂, which can be reoxidized to MoO₂Cl₂ by current reversal. A second reduction step, observed whether MoO₃ or Mo₂O₇²⁻ is added to the melt, can be attributed to the reduction of MoO₄⁻⁻, formed as a secondary reaction product in the first …

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

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

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.

A Study Of Homogeneous Catalysis By High-Pressure Kinetics. The Mechanism Of Catalysis Of A Diels—Alder Reaction, Bruce E. Poling, Charles A. Eckert

Chemical and Biochemical Engineering Faculty Research & Creative Works

The application of high-pressure kinetics as a tool to investigate the detailed mechanism of catalysis of a reaction is demonstrated. Activation volumes have been determined for the Diels-Alder addition of 2, 3-dimethylbutadiene to n-butyl acrylate, both uncatalyzed and catalyzed with AICI3. Also, partial molal volumes of reactants and products have been measured. From these data it is shown that the volume profile along the reaction coordinate is similar for both the catalyzed and uncatalyzed reactions. Further, both reactions proceed by a concerted one-step mechanism through a compact transition state with maximum accumulation of double bonds. Thus, the role of the …

Discussion, A. G. Fabula, Gary Kent Patterson

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

The Plasma Polymerization Of Vinyl Monomers. I. The Design, Construction, And Operation Of An Inductively Coupled Plasma Generator And Preliminary Studies With Nine Monomers, L. F. Thompson, Kenneth G. Mayhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

An apparatus was constructed which would allow vinyl‐type monomers (and others) to polymerize at ambient temperatures in the presence of an inductively coupled RF field. The details of the construction of the system are reported along with preliminary results obtained from nine monomers: styrene, methylvinyldichlorosilane, vinyl acetate, acrylonitrile, vinyl fluoride, 1,1‐difluoroethylene, vinyl chloride, ethylene, and 1,3‐butadiene. Copyright © 1972 John Wiley & Sons, Inc.

The Plasma Polymerization Of Vinyl Monomers. Ii. A Detailed Study Of The Plasma Polymerization Of Styrene, L. F. Thompson, Kenneth G. Mayhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

A study has been made on the plasma polymerization of styrene monomer in a cold, low‐power, inductively coupled RF plasma. Styrene monomer yielded an insoluble, crosslinked film which was slightly colored. A kinetic study is reported for styrene. The effects of power level, bleed rate of monomer, pressure, and reactor geometry on the rate of polymer formation are reported. A mechanism is postulated for plasma polymerization. It was found that the initiation step was the rate controlling step and that the reaction followed a cationic polymerization scheme. Both crosslinking and discoloration of the polymers occur at the time of polymerization …

Kinetic Analysis Of The Radiation Polymerization Of Methyl Methacrylate–Kaolin Clay Composites, J. J. Beeson, Kenneth G. Mayhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

In the first of a two‐part series, a kinetic study has been made on the effects of gamma rays (60Co) in air and inert gas on the polymerization of a 50:50 weight‐mixture methyl methacrylate (MMA)–kaolin clay system. The effect of dose rate (7.35–24.9 rads/sec), temperature (25° to 75°C), and total dose on the percentage conversion of monomer to polymer was studied. The rate of formation of polymer at 25°C in the composite system was found to be faster when compared to a bulk MMA system at the same dose rate. This acceleration showed that the clay had a catalytic effect …

Characterization Of Poly(Methyl Methacrylate) From Radiation‐Induced Polymerization In The Presence Of A Kaolin Clay Substrate, J. J. Beeson, Kenneth G. Mayhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Two types of polymer are formed in the radiation‐initiated polymerization of methyl methacrylate (MMA)–kaolin clay complexes. Homopolymer can be extracted from the complex by the use of organic solvents. Inserted polymer must be removed by dissolution of the polymer–clay complex with hydrofluoric acid. The polymers formed show no differences in structure (as determined by infrared analysis), had high molecular weights (1–5 x 106), and had similar molecular weight distributions (as determined by GPC). The molecular weights of the homopolymer increased as temperature increased (25°–75°C), and dose rate decreased (24.9–7.35 rads/sec). The isotacticity of the polymers when compared to irradiated bulk …

Entrance Effects On Capillary Degradation Of Dilute Polystyrene Solutions, J. D. Culter, Kenneth G. Mayhan, Gary Kent Patterson, A. A. Sarmasti, J. (Jacques) L. Zakin

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

Saturated Enthalpies For Mixtures Of Propane And Propene, David B. Manley, George W. Swift

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

Front Matter, University Of Missouri--Rolla

Symposia on Turbulence in Liquids

No abstract provided.

Turbulent Interface Detector Using A Multiple Array Of Single Hot Wires, W. H. Schwarz

Symposia on Turbulence in Liquids

Intermittency circuits can be used to experimentally determine some of the properties of the turbulent interface that occur in turbulent shear flows. The signal I(x,t) is unity if turbulence is present at x and zero otherwise. Using the signals obtained from detectors at one or more points, certain statistical measures of the interface position Y(x,t) can be determined. Also using a linear array of conventional single hot-wire probes, the position of the interface can be detected continuously to within some small error. The intent of this h-detector is similar to the wave-height detector used in studies of sea surfaces. The …

Experiments In Magneto-Fluid-Mechanic Natural And Forced Heat Transfer From Horizontal Hot-Film Probes, P. F. Dunn, P. S. Lykoudis

Symposia on Turbulence in Liquids

Experiments investigating magneto-fluid-mechanic effects on the heat transfer of quartz-coated hot-film probes are described. A standard heat transfer-velocity calibration curve is obtained by traversing a probe, whose axis is aligned horizontally, in the presence of a magnetic field parallel to the probe's axis. The working medium is mercury. Results indicate a significant reduction of the probe1s heat transfer in both the free and forced convection regimes.

Turbulence Measurements With The Split-Film Anemometer Probe, B. W. Spencer, B. G. Jones

Symposia on Turbulence in Liquids

The newly developed split-film anemometer probe, manufactured by Thermo- Systems, Inc. of St. Paul, Minnesota, has been applied to the measurement of two-dimensional turbulence characteristics, including turbulent shear stress, in mixing layer and boundary layer shear flows. Probes of both 6-mil and 2- mil diameters were used which had the same physical dimensions as ordinary hot-film anemometer probes. The film on this sensor is split into two 170° elements resulting in two independent sensors. This enables the probe to detect vertical as well as axial components of the instantaneous velocity vector. It therefore serves the same purpose as an x-probe, …

The Unpolarized Electrode In A Pulsating Poiseuille Pipe Flow, B. M. Bergmann, T. H. Hodgson

Symposia on Turbulence in Liquids

In recent years three workers have described methods of measurement of unsteady flow quantities in water using unpolarized electrodes. Both Binder and Chuang have attempted measurements of turbulent velocity fluctuations, whereas Dumargue described a method of fluctuating pressure measurement.

In this paper, analysis and experiment were used to critically compare the previous workers' experiments. From measurements in an oscillating Poiseuille pipe flow it is concluded that an electrode positioned in the wall detects a signal with a phase angle of π/4 ahead of the fluctuating velocity as measured by a hot-film probe in the pipe center. This is exactly the …

Current Investigations Of Turbulent Shear, S. J. Kline, G. R. Offen, W. C. Reynolds

Symposia on Turbulence in Liquids

The paper covers first a short review of the history of research on turbulent shear and second a description of current experiments which may lead to further understanding.

The first portion categorizes the kinds of data which have been taken and discusses what can be learned from each. It then summarizes what is firmly established concerning the nature of turbulent shear, mostly from work of the past decade. A description of the several interpretations of these data under theoretic study by current leading researchers is then given.

The second portion of the paper discusses the extraordinarily difficult problem of identifying …

Interpretation Of Hot-Film Anemometer Response In A Non-Isothermal Field, W. E. Burchill, B. G. Jones

Symposia on Turbulence in Liquids

A new technique for interpretation of hot-film anemometer sensor response is described. This technique has been applied to simultaneous measurement of profiles of mean velocity, the three components of velocity vector fluctuation, and temperature fluctuation in non-isothermal pipe flow of water using multiple sensors. Sensors operated in the constant temperature mode (CTA) respond to both mean and fluctuating velocity and temperature. The influence of mean temperature gradient on CTA sensor response was eliminated by appropriate adjustment of the sensors' operating resistances as the temperature gradient was traversed. The adjustments were derived from analysis of linearized CTA sensor response. A sensor …

On Velocity Measurements In Non-Isothermal Turbulent Flows, R. Chevray, N. K. Tutu

Symposia on Turbulence in Liquids

Turbulent velocity measurements in non-isothermal flows are conventionally performed by constant current hot-wire anemometry. The procedure involved however is cumbersome, the output signals are nonlinear and more critically a continuous signal of velocity fluctuations is not provided. The method described here utilizes two orthogonal wires situated a fraction of a millimeter apart. The upstream wire is operated in a low overheat, constant-current compensated mode thus providing a signal proportional to temperature while the down-stream wire, practically unaffected by the thermal wake of the first wire is operated in the constant temperature mode. Compensation for the effects of local temperature on …

Near Wall Visual Measurements In Drag Reducing Flow, H. C. Hershey

Symposia on Turbulence in Liquids

A review of several explanations for the mechanisms of drag reduction is presented. Visual studies of ordinary liquids are reviewed briefly, and visual studies in drag reducing flow are discussed. Finally, current work at Ohio State University is described where high speed motion pictures will be taken of drag reducing flow using the technique of Brodkey and Corino.

Wavevector/Frequency Spectrum Of Turbulent-Boundary-Layer Pressure, D. M. Chase

Symposia on Turbulence in Liquids

Knowledge of the wavevector/frequency spectrum of wall pressure, P(K,ω) [K = (k₁,k₃)], for a normal turbulent boundary layer has been largely confined to properties depending on the mean-convective ridge (k₁=ω/u_c). Recent theoretical work yields the wavevector dependence of P(K,ω), for flow at low Mach numbers, also in the acoustic wave number domain where K ≤ ω/c, except for undetermined functions of ωδ/U_∞. In the nonconvective but incompressive domain of wavevectors (important in underwater acoustics), apart from the proportionality to K² where ω/c ≤ K ≤ δ^-1, the …

Measurements To Elucidate The Mechanism Of Drag Reduction, R. J. Hansen

Symposia on Turbulence in Liquids

A number of investigators have attributed the reduced turbulent flow drag exhibited by polymer solutions to their high elongational viscosity. The results of a recent theoretical study of drag reduction are summarized, which show that it may instead be a consequence of the non-Newtonian behavior of polymer solutions in time-varying shear fields. Experiments are proposed to ascertain the relative importance of these transient shear effects and elongational effects in reducing drag.

Turbulent Velocity And Pressure Fields In Boundary-Layer Flows Over Rough Surfaces, W. K. Blake

Symposia on Turbulence in Liquids

This paper is a discussion of recent measurements of the statistics of the turbulent velocity and wall pressure fields in rough-wall boundary layers. These measurements, made in part by the author, have been performed over a variety of walls covering a wide range of roughness sizes and configurations. The various measurements are compared in order to determine the structure and scaling parameters of the turblulent field convected at speeds near the mean velocity of the boundary layer. The mean square turbulent velocities, their one-dimensional spectral densities, and their longitudinal and vertical microscales are compared for different walls. The velocity fields …

Effect Of Randomly Fluctuating Pressure Gradients, With Arbitrarily Specified Power Spectrum And Probability Density, On Flow In Channels, M. Perlmutter

Symposia on Turbulence in Liquids

A randomly fluctuating longitudinal pressure gradient of a non-Gaussian form and arbitrary power spectrum will cause a randomly fluctuating velocity to be superimposed on the steady incompressible flow in a channel. Pressure- gradient and velocity correlations, frequency response functions and system power loss are calculated. Numerical random pressure gradient signals were generated using Fourier series expansion, with random picking of discrete Fourier spectrum values and a nonlinear no memory transformation. Numerical values of the velocity signal were then calculated by linear transformation of the pressure-gradient signal. Pressure-gradient and velocity signals were compared for difference in amplitude, frequency, time lag, and …

Boundary Pressure Fluctuations Due To Macroturbulence In Hydraulic Jumps, F. R. Schiebe, C. E. Bowers

Symposia on Turbulence in Liquids

Data concerning the statistical properties of pressure fluctuations on the containment structure associated with the hydraulic jump have been studied at the St. Anthony Falls Hydraulic Laboratory. The incident Froude numbers were investigated through the practical range from 4 to 9. The mean square of the fluctuating pressure, the mean pressure, and the power spectrum were determined as a function of position under the jump. In addition, mean and rms turbulent velocity profiles and entrained air concentration profiles throughout the jump volume were determined.

The principal tests were performed in a channel 20 inches wide and 3 feet deep. Other …

Recent Developments Of Electrochemical Wall Mass Transfer Probes And Their Application To Drag-Reducing Polymers, T. J. Hanratty, L. D. Eckelman, G. Fortuna

Symposia on Turbulence in Liquids

Electrochemical mass transfer probes are used to measure the velocity gradient at a wall. Recent advances in their application are reviewed. These include corrections for the time response of the probe, the simultaneous measurement at a number of locations of the two components of the fluctuating velocity gradient and a study of the influence of drag reducing polymers on turbulence. It is found that drag-reducing polymers cause an increase in the scale of flow oriented eddies in the viscous sublayer.

An Experimental Investigation In A Turbulent Channel Flow With A Thick Viscous Sublayer (Hot-Film Measurements In Oil), H. Eckelmann, H. Reichardt

Symposia on Turbulence in Liquids

In a turbulent channel-flow hot-film measurements have been made. To achieve a sublayer thickness of approximately 1 cm at y⁺ = 10, oil was used. The Reynolds numbers used for the investigations were 5,600 and 8,200 based on the channel-width of 22 cm and the channel center-line velocity.

In the vicinity of the wall, y⁺ < 0.1, the u'-fluctuations were found to be proportional to the wall distance, y⁺. The u'-values obtained with a hot-film probe for y⁺ > 0.7 were all greater than those obtained with a hot-film wall probe, but extrapolation of the data from the movable hot-film probe to the wall gave good agreement with the data …

Energy Relations For Turbulent Flow In Routh Pipes, H. W. Townes

Symposia on Turbulence in Liquids

This paper describes the results of an experimental and analytical study of turbulent flow in rough pipes. Appropriate forms of mean and turbulence energy balances were developed by including mean radial and angular velocity components and using a spatial averaging technique in addition to the normal time average. An experimental program was then devised for determining the various terms in these equations. The quantities measured included the longitudinal mean velocity, rms values of fluctuating velocity components in the 3 coordinate directions, second and third order correlations between fluctuating velocities, and various components of the dissipation function. All of these quantities …