Chemical Engineering Commons^™

Periodic And Random Excitation Of Streamlined Structures By Trailing Edge Flows, W. K. Blake

Symposia on Turbulence in Liquids

This paper is an examination of semi-empirical techniques which are shown to be effective in predicting the response of hydrofoils to flow excitation. Examples are given for buffeting by inflow turbulence, excitation by the boundary-layer pressures on the hydrofoil, and linear and non-linear excitation by vortex street formation in the wake. Co-ordinated aerodynamic and hydrodynamic measurements are used in Reynolds number - scaled experiments to determine both the flow induced forces and the hydro-elastic behavior on cantilever struts. An analytical formulation based on normal mode theory is used to combine the results.

An Investigation Of The Criteria Controlling Sustained Self-Excited Oscillations Of Cylinders In Flowing Water, R. King

Symposia on Turbulence in Liquids

In this paper, water channel experimental data are discussed and compared with conventional wind-tunnel data. Stability criteria are proposed for the cross-flow and flow directions of oscillation. Fluctuating drag force coefficients are deduced from a linear mathematical representation of the cylinder located in flowing water and oscillating in the flow direction.

Local Mass Transfer In Turbulent Flow By Electrochemical Methods, C. Deslouis, I. Epelboin, B. Tribollet, L. Viet

Symposia on Turbulence in Liquids

Mass transfer to the surface of rotating electrodes during turbulent flow was studied by electrochemical methods under steady and non-steady state diffusion conditions.

The flow was due to a large rotating disk made from insulating material, flush with the surface of which was mounted a ring shaped electrode of platinum or nickel.

A local study of the radial component of the convective diffusion in turbulent flow was carried out with very thin ring electrodes (width ΔR ~ 0,05 mm). The diffusion layer thickness was varied relatively to the diffusion sublayer thickness by changing the ring width or the rotation speed …

Experimental Study Of Turbulence In Plane Separated Flows, R. Smyth

Symposia on Turbulence in Liquids

Some recent attempts at predicting turbulent two- dimensional recirculating flows have concentrated on modelling the turbulent energy equations used in the finite difference analysis methods of solutions of the elliptic partial differential equations governing these flows. These attempts have to some extent been restricted by the lack of experimental studies of the high turbulence intensities found in separated flows. The improvement of the pulsed hot-wire anemometer and the laser Doppler anemometer have made possible such studies and this paper describes an investigation using the laser Doppler anemometer in a separated flow situation. Results are given of an experimental study of …

Some Observations Of Wake Behavior In Laminar And Turbulence Free Stream Flow, L. E. Seeley, R. L. Hummel, J. W. Smith

Symposia on Turbulence in Liquids

Visual observations of the sphere wake have been obtained using the flash photolysis technique. Free stream turbulence of 7 and 10% was found to progressively reduce the size of the wake but no turbulence was found in the attached shear layer nor was the position of the separation point affected. A separation bubble was identified as predicted by Son and Hanratty (1969). Evidence is presented to show that drag reduction in turbulent free streams is not due to turbulence in the attached boundary layer but to enhanced momentum transfer in the wake.

The Roles Of Large Scale Structures In The Initial Development Of Circular Jets, F. K. Browand, J. Laufer

Symposia on Turbulence in Liquids

Experimental results are presented describing the flow field surrounding the potential core of a circular water jet in the Reynolds number region between 5,000 and 15,000. This field is divided into three regions: 1) the shear layer instability zone; 2) the vortex interaction region; and 3) the zone of higher order instability mode and turbulence generation. It is shown that the origin of the large scale structures just downstream of the potential cone can be traced to the upstream vortices, but their statistical behaviour (passage frequency, spatial coherence) seems to be independent of the initial shear layer instability.

Stereoscopic Photography Of Shear Flow Turbulence, A. K. Praturi, H. C. Hershey, R. S. Brodkey

Symposia on Turbulence in Liquids

The last several years have seen numerous advances in the understanding of the coherent motions that exist in turbulent shear flows. These studies have provided the underlying basis of most of the experimental investigations of coherent motions using conditional sampling, quadrant splitting, pattern recognition, etc. Lacking, however, in the visual work is a true three- dimensional view of the processes, which are known to be three-dimensional in nature. Possible means of providing information about the third dimension are reviewed. Details of an evaluation of a stereoscopic-photographic, high-speed motion picture system are given. The system utilizes the boundary layer flow channel …

Computer Program For Binary Distillation Using The Method Of Pochon-Savarit With Enthalpy Data Calculated By Lagrange Interpolation, Joseph J. Rogus

Theses

This thesis presents a Fortran Computer Program to solve binary distillation problems. The solution is obtained by the method of Pochon-Savarit which is based upon graphical use of an enthalpy-concentration diagram. The enthalpy data in this program is calculated using Lagrange interpolation. This is accomplished by utilizing the Lagrange interpolation to get values for the enthalpy of the vapor until we find that value which lies on the same line as the enthalpy of the liquid from the preceding tray and its corresponding del point.

The required input data consist of liquid-vapor equilibrium data, heat of solution data with the …

The Synthesis Of New Maleimide Addition Polymer Precursors, Richard B. Brown

Chemistry & Biochemistry Theses & Dissertations

1H-2,3-dimethylpyrrolo(1,2-a) benzimidazol-l-one (27) and 1H,9H- 2,3,7,8-tetramethyl-bispyrrolo(1,2-a:6,7-a')benzodiimidazo1-1,9-dione (32) have been synthesized from dimethylmaleic anhydride and o-phenylenediamine and 1,2,4,5-tetraaminobenzene, respectively. The presence of reactive olefinic double bonds in the synthesized compounds was of interest as a site for possible addition polymerization.

The synthetic route involved, in both cases, a simple nucleophilic substitution reaction between the diamine(or tetraamine) and the anhydride to form an intermediate amide-acid-amine which rapidly cyclized to the imide amine. The final ring closure required more rigorous conditions and occurred at melt reaction temperatures.

The Thermal Dehydration Of Magnesium Sulfate Hexahydrate (Mgso3.6h2o) And Magnesium Sulfite Trihydrate (Mgso3.3h2o), Raafat F. Abdel-Malek

Theses

The thermal dehydration of MgSO₃.3H₂O and MgSO₃.6H₂O have been studied by differential thermal analysis, differential scanning calorimetry and thermal gravimetric analysis.

Similar studies by other groups led to contradictory conclusions. In this investigation, these results were reconciled and it was concluded that MgSO₃.6H₂O, under equilibrium conditions, dehydrates in two steps through the intermediate formation of MgSO₃.3H₂O.

One consequence of this work is the development of a simple analytical procedure, using TGA, for the quantitative determination of both hydrates in mixtures and in the presence …

The Thermodynamics Of Electrolytic Solutions, Eric Robert Bixon

Theses

The thermodynamic properties of solutions of electrolytes may be accurately determined by the measurement of the activity of the s6lvent. when the. solute is nonvolatile, this quantity may be obtained from measurements of the lowering of the vapor pressure caused by the presence of the dissolved solute.

An experimental method has been devised to measure this effect using a semi-conventional Othmer Still. The experimental apparatus has been constructed. and evaluated. Data has been-obtained for the vapor pressure lowering of methanol due to the presence of dissolved electrolyte for five different electrolyte-methanol systems. An extrapolation technique was developed to make use …

Separation Of Isomers Via Thermal Parametric Pumping, Vincent J. D'Emidio

Theses

Continuous and semicontinuous thermal parametric pumps for separating isomers were experimentally investigated using the model system glucose-fructose-water on a cation exchange resin adsorbent. A comparison was made between the experimental data and the calculated results by a method based on an equilibrium theory. The method invokes the assumptions that a multicomponent mixture contains a series of pseudo binary systems. Each binary system consists of one of the solutes as one component and the common inert solvent as the other component. It has been shown that under certain conditions, the pump with feed at the enriched end has the capacity for …

A Preliminary Study Of The Thermodynamic Limitations Of The Nrtl/Lemf Equations, Robert Petrie

Theses

Analytical evaluations of the second and third derivatives of the molar Gibbs energy of mixing for the NRTL/LEMF equations indicate distinct zones of miscible and inmiscible prediction.

These calculations for a number of different α's have produced approximate miscibility limits for both NRTL/LEMF energy parameters and infinite dilution activity coefficients of a given system.

Transient Phenomena Of Polymer Solutions, Nikolaus Zwetkow

Theses

With the aid of a rotational viscometer, several transient phenomena were studied with different polymer solutions. In order to be acquainted with the operations of the rotational viscometer, viscosity measurements were made on polystyrene solution of a 7.14 wt. % NBS-2-35967 in a 35 - 65 mixture of aroclor and TCP, polyisobutylene (16.5% in mineral spirits), Indopol H-1900 (polyisobutylene) and 4.5% polyisobutylene in Primol 355. All these were done at a temperature of 77°F, except for Indopol H-1900 which was done at different temperatures. The results are listed in the section of tables and graphs.

Viscosity was measured with a …

Use Of Sodium Chloride Windows In The Infrared Spectral Analyses Of Irradiated Thin Insoluble Polymer Films, W. F. Oberbeck, Kenneth G. Mayhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

A Kinetic Study Of Lysine And Lysine Derivatives, Stephen Joseph Stanley

Theses

The kinetics of the reaction of iodoacetamide with lysine, polylysine, N-α-Acetyl lysine, and N-ε-Acetyl lysine, have been studied. The investigation was done at 23° C ± 123° C, as a function of pH, and concentration. In all cases it was noted that the rate of reaction increased as the pH increased. The rate data was analyzed in order to obtain the second order rate constants. In addition, the effects of the reactive site's environment on the rate was demonstrated.

Steady State Heat Transfer From A Double Ring Of Identical Spheres In A Regular Orientation, Evelio A. Melo

Theses

Solutions to Laplace's equation are obtained by the method of reflections for the problem of heat transfer from two parallel rings of spheres arranged in regular polygonal arrays. The mathematical models developed describe the rate of heat transfer and spatial temperature distribution due to an arbitrary number of identical spheres of equal surface temperature correcting Fourier's heat transfer equation for the interference caused by a multiparticle array. Although the method of solution is quite rigorous and can be used to obtain as accurate a solution as desired, only the second reflection was obtained, yielding a first order correction. The model …

Reactions Of Para-Nitroaniline With Acid Chlorides, Stephen Alan Zapoticzny

Theses

Para-nitroaniline was reacted with acid chlorides forming amides. Their structures were elucidated by the performance of various spectral analyses.

Inhibitors And Retarders For The Free Radical Polymerization Of Alpha-Methylstyrene, Alexander Accetta

Masters Theses

No abstract provided.

Creating The Electric Energy Economy, L. G. Hauser

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

My remarks will be directed to four points:

First, that energy is the life blood of our economy, and that its use or conservation is far from a simple matter of personal habits of waste or frugality. In other words, the vital role energy plays in the production of goods and services should be distinguished from its use in their consumption.

Second, that our excessive dependence on our two scarcest energy resources -- oil and natural gas -- is the core of the energy problem, both U.S. and worldwide.

Third, that limiting our time horizon to this winter, next summer, …

Energy And Transportation Policy, James S. Sagner

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

Energy shortages of recent years suggest a re-examination of national transportation policy. The lack of a coordinated approach to the solution of urban cogestion inhibits potential short-run responses to gasoline shortfalls. Longer-range policy, particularly in the context of severe financial constraints, must be carefully integrated with demonstrated patterns of urban travel and population and employment densities. Given these considerations, metropolitan areas now planning or constructing rapid rail facilities may be selecting inappropriate responses to the problem of urban access.

The Design And Performance Of A Distributed Flow Water-Cooled Solar Collector, Donald L. Spencer, Theodore F. Smith, Herbert R. Flindt

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

Design of a flat plate collector which reduces the temperature differential between the absorber plate and the fluid is described. The reduced temperature differences are shown to yield increase collector performance. Flow characteristics of the collector are examined. Collector thermal performance is illustrated for typical operating and environmental conditions. A cost analysis is presented to demonstrate that material and assembly costs are substantially lower than for any collector presently on the market.

How Might Synthetic Fuels From Coal Affect Natural Resources And Environment?, H. J. Plass Jr.

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

Energy self-sufficiency for the U. S. requires substantially increased use of coal. Direct combustion of coal without adequate environmental controls, as would occur if coal were used as a fuel for homes and offices throughout the country, would result in severe air pollution problems„ Synthetic fuels from coal such as methane, low BTU gas, or hydrogen, when utilized by the homes and businesses as gas or as electricity from gas, will contribute a much smaller amount of air pollution. However, to make these synthetic fuels available, it is necessary to mine more coal than would have to be mined for …

Two-Dimensional Analysis Of The Coherent Instationary Motion Induced By An Obstacle, Using Electrochemical Methods, B. Py, C. Tournier

Symposia on Turbulence in Liquids

The non stationary flow induced by a cylinder with a square cross-section was studied on the cylinder's surface and in the wake with two different electrochemical probes. On the cylinder was mounted split rectangular electrodes with high enough aspect ratio so as to measure the chordwise component of the wall shear stress with its sign. The non-linear response of this transducer was studied. In the wake, the longitudinal component of the velocity was obtained with conical electroactive elementswhich are mainly sensitive to this component.

The fluctuating coherent components are separated from the aleatory part of the signal and then decomposited …

Author Index, University Of Missouri--Rolla

Symposia on Turbulence in Liquids

No abstract provided.

Process Control Of Activated Sludge Treatment, Phase Ii, Richard I. Kermode, Robert W. J. Brett, Joseph D. Pault Jr.

KWRRI Research Reports

Material balances on substrate and microorganisms were derived in conjunction with various mixing configurations thought to accurately describe the activated sludge process. These models include the completely mixed with bypass, plug flow, and plug flow with bypass. Two sets of kinetic mechanisms for substrate utilization and bacterial growth were employed.

A feed forward controller was designed from linear approximations of the material balances derived in the completely mixed with bypass mixing model. Utilizing frequency response methods, the controller was found essentially identical to a completely mixed modeled controller developed in a prior investigation.

Through computer simulation the controller's effectiveness was …

An Experimental Study Of Mass Transfer To Droplets In Aqueous Polymer Solutions., Richard Gerard Schafermeyer

Masters Theses

"Instantaneous and time-average mass transfer coefficients for 1 the free-fall period was obtained for transfer of iodine from nonNewtonian continuous phases to carbon tetrachloride drops. The nonNewtonian continuous phases were aqueous solutions of carboxymethyl cellulose and carboxy polymethylene. Although a few exceptions were found, the continuous phase mass transfer coefficients were, in general, found to decrease with increasing time of drop contact. Comparisons of the experimental data to theoretical relations showed that changes in drop internal circulation probably occurred for that data which showed a time effect for the mass transfer coefficient. Several explanations for the time effect were offered, …

Conference Proceedings Of The 4th Biennial Symposium On Turbulence In Liquids, University Of Missouri--Rolla

Symposia on Turbulence in Liquids

No abstract provided.

On The Role Of Conditional Averages In Turbulence Theory, R. J. Adrian

Symposia on Turbulence in Liquids

It is shown that conditional averages in the form of expected values of functions of the velocity at an arbitrary point given the velocities at a finite number of distinct points, appear naturally in certain types of turbulence theories and that the closure problems in such theories ultimately reduce to the approximation of these averages. Two exemplary theories are considered. The first is characteristic of turbulence models formulated in terms of probability density functions whereas the second is related to the derivation of optimal algorithms for the numerical integration of the turbulent Navier-Stokes equations at large Reynolds numbers. Some mathematical …

Mechanical Degradation Of Dilute Solutions Of High Polymers In Capillary Tube Flow, John D. Culter, Jacques L. Zakin, Gary Kent Patterson

Chemical and Biochemical Engineering Faculty Research & Creative Works

Experimental results on mechanical degradation in capillary tubes of polyisobutylene polymers in dilute solution are described. In laminar flow, degradation is independent of tube length, indicating that entrance effects are dominant. This shows that capillary experiments do not yield explicit information on the effect of shear stress on mechanical degradation. In turbulent flow, large entrance effects are also observed, but some degradation does take place in the fully developed flow region. Copyright © 1975 John Wiley & Sons, Inc.