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Full-Text Articles in Engineering

Bibliography Of Hot-Wire-Film Anemometry In Liquids, R. L. Humphrey Sep 1969

Bibliography Of Hot-Wire-Film Anemometry In Liquids, R. L. Humphrey

Symposia on Turbulence in Liquids

It is not a new idea to use heat transfer from a hot sensor in a fluid stream to measure velocity and turbulence. This was done as long ago as 1909 by Mr. Kenelly, but a systematic study was not followed through until 1914 by L. V. King. After this followed a series of dedicated people, some students, some professors, some scientists, who continually advanced the state of the art of anemometry in liquids. This paper deals with their work in the areas of electronics (integrated circuits) and physics (thin film technology), and shows how, in time, these two areas …


Some Basic Properties Of Low Quality Two-Phase Turbulent Flow, G. Hetsroni, S. Einav Sep 1969

Some Basic Properties Of Low Quality Two-Phase Turbulent Flow, G. Hetsroni, S. Einav

Symposia on Turbulence in Liquids

This Is an exploratory study dealing with the effect of gas bubbles on the turbulence Intensity of the liquid in a two-phase flow.

Distributions of time-mean and fluctuating velocities were measured in a two - dimensional channel. These were measured for single-phase flow and on the two sides of a bubble layer, which simulated the two-phase flow.

In single-phase flow the distribution of the time-mean velocities agrees well with other data, while the distribution of the Intensity of turbulence Is lower than expected.

The measurements of the time-mean velocity and turbulence Intensity across the bubble layer revealed that they are …


Turbulence Measurements In Stably Stratified Fluids, Yih-Ho Pao Sep 1969

Turbulence Measurements In Stably Stratified Fluids, Yih-Ho Pao

Symposia on Turbulence in Liquids

A towing tank system was used to study the structure of turbulence in stably stratified fluids. Turbulence is generated by moving an obstacle (a grid or a cylinder) in a tank of stratified salt water. Recent improved shadowgraph pictures of these laboratory generated stratified flows are shown in this paper. They give further support to Pao's observation that (i) internal waves and turbulence coexist in turbulent stratified flows, with internal waves at the large scales and turbulence at the small scales; (ii) turbulence decays much more rapidly than internal waves; and (iii) the turbulent-nonturbulent interfaces are not necessarily sharp, and …


The Response Of A Hot-Wire Anemometer To A Bubble Of Air In Water, S. C. Chuang, V. W. Goldschmidt Sep 1969

The Response Of A Hot-Wire Anemometer To A Bubble Of Air In Water, S. C. Chuang, V. W. Goldschmidt

Symposia on Turbulence in Liquids

The sensitivity of peak voltage drop and duration of the change In sensor voltages due to the impaction of different size bubbles are confuted and measured. Excellent agreement between these is found for bubbles somewhat larger than the sensor diameter and smaller than Its effective length in water streams in a range of 1.5 to 9 feet per second. The method suggests a reliable method for sizing bubbles in a water stream. The effects due to nondirect hits are not treated.


Experimental Investigation Of Polymer Solution Injection On External Boundary Layers, Brian Latto, Chi-Hung Shen Sep 1969

Experimental Investigation Of Polymer Solution Injection On External Boundary Layers, Brian Latto, Chi-Hung Shen

Symposia on Turbulence in Liquids

This paper describes an experimental study of the effects of injecting dilute aqueous polymer solutions into a turbulent boundary layer formed on a flat plate immersed in flowing water.

Hot-film anemometer techniques were employed in the measurement of the velocity profiles, turbulence intensities, and lateral correlation coefficients at a number of locations along the plate. Boundary layer growth parameters and the variation of the local skin friction coefficient were computed from the velocity profile data. The effects of polymer concentration and injection velocity on the local drag reduction are also presented.

It was found that momentum diffusivity was smaller than …


Turbulence Measurements In Dilute Polymer Flows, Joseph M. Wetzel, John A. Almo, John M. Killen Sep 1969

Turbulence Measurements In Dilute Polymer Flows, Joseph M. Wetzel, John A. Almo, John M. Killen

Symposia on Turbulence in Liquids

A hot-film sensor was flush-mounted in the wall of a four-inch pipe and was calibrated as a function of wall shear stress. Flows with water and with homogeneous aqueous solutions of Polyox WSR-301 were utilized. The heat transfer characteristics of the sensor were reduced for polymer flows. Measurements of the number of zeroes and the frequency spectra for the turbulent fluctuations were obtained for a variety of test conditions. The effects of Polyox WSR-301 on surface pressure fluctuations on both smooth and rough surfaces were also measured.


Some Aspects Of Flow Through Rotating Circular Tubes, D. L. Boyer, J. R. Guala Sep 1969

Some Aspects Of Flow Through Rotating Circular Tubes, D. L. Boyer, J. R. Guala

Symposia on Turbulence in Liquids

The flow of water in a circular tube rotating about an axis perpendicular to the axis of the tube is studied. Information about the flow is obtained from coated hot-film probes and a constant temperature anemometer. A maximum Reynold's number of 9,500 is obtained and the Taylor number is varied from 800 to 3,100. Little similarity is found to exist between flows in rotating and in non-rotating systems in this range of parameters.


An Experimental Facility For The Visual Study Of Turbulent Flows, Robert S. Brodkey, Harry C. Hershey, Edward R. Corino Sep 1969

An Experimental Facility For The Visual Study Of Turbulent Flows, Robert S. Brodkey, Harry C. Hershey, Edward R. Corino

Symposia on Turbulence in Liquids

An experimental technique which allows visual observations of the wall area in turbulent pipe flow is described in detail. It requires neither the introduction of any injection or measuring device into the flow nor the presence of a two-phase flow or of a non-Newtonian fluid. The technique involves suspending solid MgO particles of colloidal size in trichloroethylene and photographing their motions near the wall with a high speed movie camera moving with the flow. Trichloroethylene was chosen in order to eliminate the index of refraction problem in a curved wall.

Evaluation of the technique including a discussion of limitations is …


Experimental Investigation Of The Hydrodynamic Stability Of Flow In Rotating Pipes Using Thermistors, Hassan M. Nagib, Ludwig Wolf Jr. Sep 1969

Experimental Investigation Of The Hydrodynamic Stability Of Flow In Rotating Pipes Using Thermistors, Hassan M. Nagib, Ludwig Wolf Jr.

Symposia on Turbulence in Liquids

The hydrodynamic stability of flow in a rotating pipe Is investigated experimentally using thermistors. The experimental apparatus consists of a rotating pipe made of lucite, 3-1/4 inch inside diameter, six feet long, equipped with porous plugs at the ends to minimize recirculation. The working fluid is water and a range of axial and tangential Reynolds numbers up to 7,000 and 20,000, respectively, is covered. Thermistors were chosen for this study since their high electrical resistivity yields strong signals which permit the use of inexpensive and convenient electronics. They also have a high temperature coefficient of electrical resistance which minimizes the …


The Structure Of A Turbulent Water Jet, Philip J. Morris Sep 1969

The Structure Of A Turbulent Water Jet, Philip J. Morris

Symposia on Turbulence in Liquids

Experimental studies are made to determine the structure of a turbulent water jet.

The paper is divided into two parts. The first gives practical information about the techniques and instrumentation developed to make measurements with hot-wire anemometers in water. A short theoretical discussion is given on the dynamic response of heated fibre in liquids. The second part reports on the results obtained in a one-inch water jet at Reynolds numbers between 12,000 and 20,000. Mean axial velocity measurements are made in the initial five diameters of the jet and the results are used to predict the nature of the vortex …


Author Index, University Of Missouri--Rolla Sep 1969

Author Index, University Of Missouri--Rolla

Symposia on Turbulence in Liquids

No abstract provided.


Diffusion Coefficients Over Rough And Smooth Boundaries, Obtained By Measuring The Concentration-Velocity Covariance, R. S. Mcquivey, T. N. Keefer Sep 1969

Diffusion Coefficients Over Rough And Smooth Boundaries, Obtained By Measuring The Concentration-Velocity Covariance, R. S. Mcquivey, T. N. Keefer

Symposia on Turbulence in Liquids

A preliminary investigation of the coefficients of turbulent diffusion in an open channel was conducted by employing: 1) hot-film anemometry to detect the velocity fluctuation, 2) a platinized single-electrode conductivity probe to detect the concentration fluctuations, and 3) a digital computing system to evaluate the covariance and other statistical properties of the two output signals.

Data were collected downstream of a constant-discharge point source of neutrally-bouyant salt solution at stream temperature and velocity. Using current semi-empirical methods diffusion coefficients were obtained in the vertical and lateral directions as well as dispersion coefficients due to convection.


Use Of A Constant Temperature Hot-Wire Anemometer To Compensate For The Thermal Lag, Peter Freymuth Sep 1969

Use Of A Constant Temperature Hot-Wire Anemometer To Compensate For The Thermal Lag, Peter Freymuth

Symposia on Turbulence in Liquids

A constant temperature hot-wire anemometer can be used to compensate for the thermal lag of a wire or film resistance thermometer within the useful frequency range of the anemometer. This method may be used as an alternative to the standard method in which a differentiation circuit as employed in constant current anemometers is used for frequency compensation. The new method is useful if a constant temperature anemometer is at hand. The time constant of the resistance thermometer need not be determined.


Measurements Of Turbulence Characteristics In Water And In Dilute Polymer Solutions, Tadeusz Kowalski Sep 1969

Measurements Of Turbulence Characteristics In Water And In Dilute Polymer Solutions, Tadeusz Kowalski

Symposia on Turbulence in Liquids

Measurements of turbulence characteristics were made inside a boundary layer in external flow of water and in water with polymer additives of the Polyox type. Flush mounted hot-film sensors and wedge, parabolic, and cylindrical sensors were used to measure the turbulent velocity fluctuations. Graphs are given of energy density, dissipation, turbulence shear correlation spectra, and microscale of turbulence distribution. Tests were run in an open channel flow at one Reynolds number and two rates of polymer injection to give 20 and 40 ppm average concentration in the boundary layer. The results indicate that the advent of the quartz insulated hot-film …


Frequency Response Studies For A Wedge Probe In Viscoelastic Fluids, J. M. Rodriguez, Gary Kent Patterson, J. L. Zakin Sep 1969

Frequency Response Studies For A Wedge Probe In Viscoelastic Fluids, J. M. Rodriguez, Gary Kent Patterson, J. L. Zakin

Symposia on Turbulence in Liquids

The response of a hot-film wedge probe in viscoelastic fluids has been investigated by imposing on the probe a sinusoidal vibration of known amplitude and frequency. Root-mean-square (rms) velocities calculated from the displacement of the probe were compared to rms velocities obtained with a constant temperature anemometer. The tests were performed under turbulent flow conditions and also at flow rates where viscoelastic effects (i.e., decrease of heat transfer rates from the probe to the fluid and drag reduction) were observed.

The frequency range covered was narrow ( < 100 cps). This limitation was imposed by the decision to superimpose the sinusoidal vibrations on the turbulence signal, in order to have dynamic conditions similar to those encountered in actual turbulence measurements. Measurements were performed in mineral oil and four solutions of polyisobutylene (Vistanex L-200) In mineral oil.

The experimental technique was established by measuring the response of the probe in …


Diffusion Coefficients Of D-Glucose In Aqueous Carboxymethylcellulose And Carboxypolymethylene Solutions, A. L. Huang, S. V. Desai, Robert M. Wellek Jul 1969

Diffusion Coefficients Of D-Glucose In Aqueous Carboxymethylcellulose And Carboxypolymethylene Solutions, A. L. Huang, S. V. Desai, Robert M. Wellek

Chemical and Biochemical Engineering Faculty Research & Creative Works

A micro interferometric method was used to determine pseudo-binary, molecular diffusion coefficients for diffusion of D-glucose in aqueous carboxymethylcellulose (CMC) and aqueous carboxypolymethylene (Carbopol) solutions. An initial solute concentration of about 9 wt. % D-glucose in the aqueous polymer solutions was used. The polymer concentrations for the CMC solutions ranged from 1.2 to 2.2 wt. % and for the Carbopol solutions from 0.18 to 0.28 wt. %. Diffusion coefficients were determined as a function of reduced solute concentration, both with and without the effect of solution volume change during diffusion being considered. © 1969, American Chemical Society. All rights reserved.


A Simple Observational Technique For The Investigation Of Boundary Layer Stability And Turbulence, Tony Maxworthy Jan 1969

A Simple Observational Technique For The Investigation Of Boundary Layer Stability And Turbulence, Tony Maxworthy

Symposia on Turbulence in Liquids

A dense suspension of aluminum flakes in a fluid has many advantages as a flow-visualization method, and has been used to study circular Couette flow and Benard instability, among others. In the present contribution the scientific and pedagogical merits of the technique are examined further for three different cases: (a) Stability of Poiseuille flow; (b) Stability of the side-wall boundary layers created when a fluid-filLed, rotating container is suddenly brought to rest; (b) Stability of the boundary layer beneath a concentrated vortex.

The technique is also useful in other cases, especially when fundamentals of fluid flow are to be demonstrated …


Measurements Of Density Fluctuations In Submerged Water Jets, L. N. Wilson, D. W. Prosser Jan 1969

Measurements Of Density Fluctuations In Submerged Water Jets, L. N. Wilson, D. W. Prosser

Symposia on Turbulence in Liquids

A remote sensing technique, free from many of the problems associated with Inserting probes into a liquid flow, has been developed to measure turbulent density fluctuations In a low speed, submerged water jet. The technique employs two schlieren optical systems, composed of He-Ne lasers and photo detectors. The optical beams intersect in the flow in a plane perpendicular to the flow direction. Knife edges are aligned such that the systems are sensitive to gradients of refractive index in the flow direction. An analysis is presented which relates the cross-covariance of the two signals to the local two-point refractive-index covariance and …


Effect Of Dilute Polymer Solutions On External Boundary Layers, Brian Latto, J. A. Middleton Jan 1969

Effect Of Dilute Polymer Solutions On External Boundary Layers, Brian Latto, J. A. Middleton

Symposia on Turbulence in Liquids

The paper reports an experimental study of the flow of homogeneous aqueous polyacrylamide MRL 402 solution over a thin flat plate. Extensive velocity profile data were obtained, using both cylindrical and conical hot-file probes, and used to obtain local skin friction profiles. Direct drag measurements were made over a period of time for concentrations of 0, 25, 50 and 75 wppm and indicated that there was no appreciable degradation of the polymer. Extensive turbulence intensity data were obtained which were contradictory but indicated that the conical type probe is better than the cylindrical type for turbulence measurements and that the …


Conference Proceedings Of The Symposium On Turbulence Measurements In Liquids, September 1969, University Of Missouri--Rolla Jan 1969

Conference Proceedings Of The Symposium On Turbulence Measurements In Liquids, September 1969, University Of Missouri--Rolla

Symposia on Turbulence in Liquids

No abstract provided.


Mass And Heat Transfer Relations In Evaporation Through Porous Membranes, Marshall E. Findley, V. V. Tanna, Y. B. Rao, C. L. Yeh Jan 1969

Mass And Heat Transfer Relations In Evaporation Through Porous Membranes, Marshall E. Findley, V. V. Tanna, Y. B. Rao, C. L. Yeh

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study concerns rates of evaporation and mass transfer of water vapor from a heated salt solution through a water repellent porous membrane to a cooled water condensate. This transfer is a result of temperature differences and corresponding vapor pressure differences across the membrane. Three groups of experiments were carried out which indicate that the major factor influencing the rates of transfer is diffusion through a stagnant gas in the membrane pores. However, an equation considering film heat transfer coefficients, membrane thermal conductivity, and an empirical correction based on temperature driving force appears to be necessary for representing all the …


Comparison Of Lagrangian Time Correlations Obtained From Dispersion Experiments And From Space‐Time Correlation Functions, J. M. Rodriguez, Gary Kent Patterson Jan 1969

Comparison Of Lagrangian Time Correlations Obtained From Dispersion Experiments And From Space‐Time Correlation Functions, J. M. Rodriguez, Gary Kent Patterson

Chemical and Biochemical Engineering Faculty Research & Creative Works

No Abstracts. Copyright © 1969 American Institute of Chemical Engineers


Prediction Of Drag Reduction With A Viscoelastic Model, Gary Kent Patterson, J. L. Zakin Jan 1968

Prediction Of Drag Reduction With A Viscoelastic Model, Gary Kent Patterson, J. L. Zakin

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.


Numerical Differentiation Of Equally Spaced And Not Equally Spaced Experimental Data [3], Harry C. Hershey, Jacques L. Zakin Jan 1968

Numerical Differentiation Of Equally Spaced And Not Equally Spaced Experimental Data [3], Harry C. Hershey, Jacques L. Zakin

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.


Water Quality Study Of Lake Mead, Dale A. Hoffman, Paul R. Tramutt, Frank C. Heller, Bureau Of Reclamation Nov 1967

Water Quality Study Of Lake Mead, Dale A. Hoffman, Paul R. Tramutt, Frank C. Heller, Bureau Of Reclamation

Publications (WR)

This report presents Lake Mead Water quality data obtained from 1964 to 1966. The effect of filling Lake Powell on the water quality of Lake Mead is evaluated. General limnological principles and the present limnology of Lake Mead are discussed. Lake Mead has a warm monomictic annual temperature cycle characterized by summer stratification, fall overturn leading into a continuous circulation throughout the winter; temperatures never fall below 39 deg F (4 deg C). During stratification, lower dissolved oxygen values were recorded in the thermocline than in the epilimnion and hypolimnion. Mineral content increases from the upper to the lower end …


Existence Of Two Types Of Drag Reduction In Pipe Flow Of Dilute Polymer Solutions, Harry C. Hershey, Jacques L. Zakin Aug 1967

Existence Of Two Types Of Drag Reduction In Pipe Flow Of Dilute Polymer Solutions, Harry C. Hershey, Jacques L. Zakin

Chemical and Biochemical Engineering Faculty Research & Creative Works

Drag reduction in the pipe flow of polymer solutions is shown to be of two types which apparently occur by two separate mechanisms. In turbulent flow, drag reduction is probably caused by viscoelastic effects. The critical solvent Reynolds number at the onset of drag reduction is proportional to about the first power of the diameter. Thus, the critical velocity is independent of tube diameter. Polymers dissolved in good solvents show more drag reduction than in poor solvents. The other type of drag reduction occurs when the laminar region is extended to high Reynolds numbers. It is followed by a transition …


Numerical Differentiation Of Equally Spaced And Not Equally Spaced Experimental Data, Harry C. Hershey, Jacques L. Zakin, Robert Simha Aug 1967

Numerical Differentiation Of Equally Spaced And Not Equally Spaced Experimental Data, Harry C. Hershey, Jacques L. Zakin, Robert Simha

Chemical and Biochemical Engineering Faculty Research & Creative Works

Procedures are given for smoothing and differentiating experimental data with both equal and nonequal spacing in the independent variable. Selection of the number of points to be included in the "movable strip" technique and of the degree of the polynomial is discussed. Equations are given to estimate the error by calculating a confidence interval on each slope. A technique for handling certain types of nonrandom errors is presented. © 1967, American Chemical Society. All rights reserved.


Trace Element Content Of Magnetites And Hematites, Southeast Missouri Iron Metallogenic Province, Usa, Geza Kisvarsany, Paul Dean Proctor Jun 1967

Trace Element Content Of Magnetites And Hematites, Southeast Missouri Iron Metallogenic Province, Usa, Geza Kisvarsany, Paul Dean Proctor

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Six major and numerous smaller Precambrian iron deposits of mag-matic origin occur in the volcanic rocks of the Southeast Missouri Iron Metallogenic Province in an area approximately 70 miles long and 40 miles wide. The Precambrian igneous complex is composed of mainly high silica, with some intermediate, volcanic rocks intruded by granitic rocks and some diorites and gabbros. Biotite schists occur locally. Some of the volcanic and intrusive rocks are characterized by an unusual abundance of alkali metals. Local enrichments in fluorite, calcite, and iron oxides are present. The shapes of the iron deposits range from massive tabular to irregular. …


Vaporization Through Porous Membranes, Marshall E. Findley Apr 1967

Vaporization Through Porous Membranes, Marshall E. Findley

Chemical and Biochemical Engineering Faculty Research & Creative Works

Mixtures may be evaporated from one interface of a Non wettable porous membrane with diffusion through the vapor-filled pores and condensation at the other interface of the membrane, by a sufficiently higher temperature on the mixture side maintained by a heat supply to the mixture and heat removal from the condensate equal to the latent heat transferred with vapor plus heat transferred by conduction. This permits essentially infinite-stage flash evaporation at constant liquid pressures, either with diffusion through Non condensable gases in the pores, or with vapor flow at a lower pressure than liquid pressures, but with liquids excluded from …


Variation In Gold Content Of Minerals Of The Marysville Quartz Diorite Stock, Montana, Erwin J. Mantei, Arthur H. Brownlow Jan 1967

Variation In Gold Content Of Minerals Of The Marysville Quartz Diorite Stock, Montana, Erwin J. Mantei, Arthur H. Brownlow

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Neutron activation analysis for gold has been carried out on 135 mineral samples from throughout the Marysville stock with the following results: (1) the gold content of 44 biotite ranges from 0·002 to 0·924 ppm with an average of 0·076 ppm; (2) 37 hornblende samples gave a range of 0·003-0·823 ppm and an average of 0·100 ppm; (3) for 44 magnetite samples the range was 0·003-0·329 ppm and the average 0·037 ppm; (4) 10 quartz-feldspar samples varied from 0·006 to 0·176 ppm with an average of 0·065 ppm. High gold values mainly occur near the edge of the stock and …