Engineering Commons^™

Stafford Letter To Astronaut Group - Prestige And Morale, Thomas P. Stafford

Articles

On October 8th, 1969, then Chief of the Astronaut Office at NASA, Thomas P. Stafford, addressed the rest of the astronaut group in a letter about group prestige and morale.

Channel And Z-Sections Braced By Diaphragms, Nuri Celebi, George Winter

CCFSS Library (1939 - present)

The behavior of thin-walled cold formed channel and Z-sections, braced on their upper flange by light-gage steel diaphragms under static loading is studied. The objective of the study is to obtain mathematical solutions, to verify these solutions by tests, and to derive design formulations for the bending behavior of channel and Z-section beams with various boundary conditions. This type of structural element is encountered as purlins and girts to support the roof cover and siding of metal buildings. The roof cover is connected to the upper flange of the purlins and gives rise to the case of braced compression flange …

A Liquid Extraction Column With Reciprocated Wire Mesh Packing, Robert M. Wellek, M. Uran Ozsoy, J. J. Carr, Dudley Thompson, Thomas V. Konkle

Chemical and Biochemical Engineering Faculty Research & Creative Works

In a new type of pulsating, liquid extractor, pulsating energy is added to the counter currently flowing liquid streams by a stainless-steel wire mesh packing which is reciprocated vertically in a 3-inch i.d. extraction column. The mass transfer performance and flooding characteristics are studied as a function of the frequency and amplitude of reciprocation, the total solvent and feed throughputs, and choice of phase dispersion. The benzene-HAc-H₂O and MIBK-HAcH₂O systems were used. Extraction data for the benzene system were correlated in terms of a dimensionless pulse velocity group. Operating throughputs are significantly higher than those achieved …

Engineering Geognosy Of Warren County, Jerry G. Pigman, Tommy C. Hopkins

Kentucky Transportation Center Research Report

Engineering soils and geologic maps are proving to be invaluable to engineers, industrial leaders, community planners, and administrators during the preliminary stages of planning and site selection. Quantitative engineering data on soils and geological formations, and the interpretation of these data, are important factors to consider in developing the best land-use plans and providing stable foundations for highways, buildings, and other structures, such as dams. Information of this type, when available, is being used by public and private organizations in planning urban development. Engineering soils and geologic maps can be used to great advantage in four major ways by planners …

Grooving Pavement Centerlines For Lane Demarcation, Ronald D. Hughes, Gordon R. Garner

Kentucky Transportation Center Research Report

Lane demarcation is conventionally accomplished by use of white traffic paint placed as a skip line. Most traffic paints are beaded by premixing glass beads in the paint, by drop-on applications, or a combination of the two. The retrodirective properties of the beads greatly enhance nighttime visibility during dry weather; however, visibility of the lines is practically nil during wet nighttime driving. Submerged beads cannot redirect the light when the need for guidance is mosL critical. Thermoplastic striping materials have been used to varying degrees of success by numerous agencies. Wet nighttime visibility of thermoplastics, as experienced in Kentucky, is …

Selected Features Of Kentucky Geology From Lexington To Pineville, Herbert F. Southgate, Tommy C. Hopkins, Gordon D. Scott

Kentucky Transportation Center Research Report

Kentucky has been disturbed by two major catastrophic events. The major portion of the state was upheaved to what is referred to as the Cincinnati Anticline, and erosion has resulted in forming of several physiographic regions, four of which will be traversed on this trip--namely, the Inner Blue Grass region, the Outer Blue Grass region, the Knobs, and the Eastern Coal Fields. The second major catastrophic event was the Appalachian folding, of which the Pine Mountain Overthrust and its faulting affects the southeastern Kentucky area.

The Inner Blue Grass region contains the lowest exposed geologic formation in Kentucky which is …

A Note On The Free Distance Of A Convolutional Code, Alexander Miczo, Luther D. Rudolph

Electrical Engineering and Computer Science - All Scholarship

A counterexample to a conjecture on the number of constraint lengths required to achieve the free distance of a rate l/n systematic convolutional code is presented.

Test 1025: John Deere 5020, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

The Static And Dynamic Balance Of Rotating Mechanisms In The Automobile, Joel E. Tjelmeland

Graduate Research Papers

What are the physics and mechanics involved in the static and dynamic balance of rotating mechanisms in the automobile? To what degree is balance necessary in the various mechanisms? What machines are available for balancing the various mechanisms? What are the skills involved in the balance of these mechanisms? How can the materials available best be organized into a unit which can be used in the industrial arts power and automotive programs?

Simulation Of Periodic Tank Reactors, Noshir Pirojshaw Mistry

Dissertations

Normally it is assumed that the steady state mode of operation is most desirable for the design of the chemical reactor system. However it appears that this assumption may not be correct in many cases.

In the present work disturbances of various types were externally created and forced on a system comprising an isothermal continuous stirred tank reactor. The effects of these purposefully created disturbances were investigated by mathematically modelling the system and simulating it on a digital computer.

The change in reactor performance, as defined by the percentage change in the production rate from the steady state value, can …

Test 1023: John Deere 4000, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1024: John Deere 4020 Power Shift, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Measurement Of Fluid Velocities In A Simulated Heat Pipe, Lewis Collin Moore

Mechanical Engineering ETDs

Velocity components of numerous geometries may be measured with the laser Doppler technique. Combinations of system parameters were investigated that were useful for constructing a two-dimensional velocimeter for a tube with porous walls. A method was developed which combined a local oscillator with a crossed-incident beam using backscatter at very small angles from the longitudinal axis. Seeding requirements, electronics signal processing, permeability measurements, and measurement point constraints were investigated. Preliminary fluid velocity results were obtained, and recommendations are made for further improvements to overcome the difficulties encountered in the current investigation.

Response Of The Lower Vertebral Column To Caudocephalad Acceleration, A. Peter Vulcan

Wayne State University Dissertations

This dissertation is concerned with the measurement of the response, in those areas of the vertebral column where fractures are most common, when the seated human is subjected to caudocephalad acceleration. Such accelerations and consequent vertebral fractures are experienced not only in ejection from aircraft, but also in survivable helicopter and aircraft crashes, and in certain types of falls. It is intended that the measurements should provide a better understanding of the mechanisms of vertebral fracture and data for the formulation of an appropriate mathematical model.

Test 1022: Massey-Ferguson Mf 1080 (Diesel), Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …

Test 1020: Massey-Ferguson Mf 175 (Gasoline), Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …

Test 1021: Massey-Ferguson Mf 180 (Gasoline), Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …

Test 1019: David Brown 4600 Selectamatic (Gasoline), Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …

Test 1018: David Brown 3800 Selectamatic (Gasoline), Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF TEST REPORT GENERAL CONDITIONS East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers. PREPARATION FOR PERFORMANCE RUNS The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …

Front Matter, University Of Missouri--Rolla

Symposia on Turbulence in Liquids

No abstract provided.

The Influence Of Ambiguity And Noise On The Measurement Of Turbulent Spectra By Doppler Scattering, J. L. Lumley, W. K. George, Y. Kobashi

Symposia on Turbulence in Liquids

A fundamental uncertainty in velocity measurement by Doppler scattering is caused by the finite residence time of the scattering particles in the observation volume; the arrival of scattering particles at arbitrary times gives rise to fluctuations in phase (and hence frequency) of the observed Doppler frequency. An estimate is obtained for the spectrum of these frequency fluctuations (called ambiguity noise). The frequency at which the spectral levels of a turbulent signal and the ambiguity noise are equal, provides a limit to the temporal resolution of an instantaneous velocity measurement; this limit is obtained, and shown to be quite restrictive. The …

Laser-Doppler Measurements Of The Decay Of Velocity Fluctuations In Dilute Polymer Solutions, Neil S. Berman, Eugene E. Cooper

Symposia on Turbulence in Liquids

Finite disturbances were generated in a pipe containing water or a 20 ppm solution of Separan AP-30 in water by oscillating a sleeve at the wall. The sleeve amplitude in the axial direction varied from 0.5 to 2.0 inches and the frequency from 0.25 to 1.0 Hz. Downstream of the sleeve oscillations in the fluid velocity were measured with a laser Doppler flowmeter at various axial and radial positions to determine behavior at the lower frequency part of the stability curve for water. The response amplitude, phase angle and the mean velocities were measured for both fluids at Reynolds numbers …

Optical Statistical Measurements Of Free Convection Flow Patterns, E. F. C. Somerscales

Symposia on Turbulence in Liquids

Measurements have been made of the autocorrelation of photographs of the flow patterns produced at high Rayleigh numbers in a horizontal layer of liquid heated from below and cooled on top. The relation of these measurements to temperature measurements in the fluid are considered. Analogous situations in other physical systems are also discussed.

The Use Of Electrochemical Techniques To Study Turbulence Close To A Wall, Kamalesh K. Sirkar, Thomas J. Hanratty

Symposia on Turbulence in Liquids

Electrochemical techniques can be used to measure the time averaged velocity gradient and the two components of the fluctuating velocity gradient at a solid surface. A chemical reaction Is carried out at the surface of a small electrode embedded in the wall. The voltage applied to the electrode Is large enough that the current flowing in the circuit is controlled by the mass transfer rate. The probes are the mass transfer analog of the hot wire or hot film anemometer. If the test electrode is part of a large electrode surface, it can be used to measure local time averaged …

Ultrasonic Study Of Turbulent Water Flow, W. K. Kramer, R. Grosskreutz, A. Dinkelacker

Symposia on Turbulence in Liquids

The propagation of ultrasonic waves through turbulent water flow has been Investigated experimentally. While passing the turbulent region the sound waves are modulated to some extent. The degree of modulation and the frequency spectra of the modulation are closely related to the properties of the flow. It seems to be possible to use this method for turbulence measurements in liquids, whereby the absence of a probe in the flow region and a possibility to differentiate between velocity and density fluctuations would be special advantages. A disadvantage can be the fact that Information is collected on the whole sound path.

Turbulence Measurements In Water, Francois J. Resch

Symposia on Turbulence in Liquids

Turbulence measurements in water have been undertaken using hot film anemometers in a circular conduit. Two different types of film probe were tested and the problem of drift of the calibration curves was carefully studied. A heat transfer law was established for conical hot film probes.

Some turbulence measurements, made at the axis of the pipe, were compared with the corresponding measurements undertaken in air flow. The comparison led to the conclusion that turbulence measurements can be carried out in water with the same degree of accuracy as those carried out in dynamically similar air flow.

Two-Dimensional Laser-Doppler Velocimetry In Turbulent Flows, N. E. Chatterton, R. D. Lewis, E. W. George

Symposia on Turbulence in Liquids

Localized measurement of the velocity of flow In fluids may be accomplished by detecting the Doppler shift In frequency from coherent, monochromatic light scattered from micrometer sized contaminant particles within the flow. The versatility of applications of this technique, first used several years ago, has been expanded by recent research. The basic geometry of measurement, in which the scattered energy is recombined with light energy at the original frequency on the face of the photocathode of a photomultiplier tube, can be rearranged in many alternative configurations to meet the needs of the experimenter. By using a single laser, additional arrangements …

Turbulence Measurements In Shear Flow Liquid Systems, Robert S. Brodkey, M. F. Cohen, J. S. Knox, G. L. Mckee

Symposia on Turbulence in Liquids

The paper is a composite of a number of years of work on turbulence measurements in a variety of liquid flow systems. The trials and tribulations of such measurements are emphasized. Pipe flow Is considered in some detail, and the consistency between results of various investigators is analyzed. Other systems discussed are a stirred tank unit and a multi-jet reactor configuration. Statistical turbulence measurements such as autocorrelation, spectrum, probability density, flatness factor, and skewness factor are considered in terms of obtaining these from digital signals obtained by conversion of the normal analog signals. Descriptive parameters of statistical turbulence, such as …

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

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 …