Engineering Commons^™

Numerical Simulation Of Mixing Processes In Two-Dimensional Channel Flows, Milan Karel Straka

Doctoral Dissertations

"Recently, considerable interest has arisen in the numerical simulation of laminar and turbulent transport phenomena. More knowledge in this field is needed to improve predictions of heat and mass transfer processes in a variety of technical fields.

In this work a new computationally efficient transport model is developed. It consists of partially parabolized time-dependent equations of motion, continuity, and concentration of nonconservative species. Pertinent equations are solved numerically for both laminar and turbulent flow.

Results of calculations of laminar flow in the entry region of a parallel-plate channel agree well with the work of other authors. For turbulent flows, the …

Kinetics And Reactor Design In The Pyrolysis Of Tar Sands, Charles Arthur Lechner

Doctoral Dissertations

"Data from the thermal decomposition of bitumen from Utah tar sands was obtained and analysed with both isothermal and non-isothermal chemical reaction models. The use of a power rate law to describe the complex kinetics of pyrolysis gave agreement with the experimental data that was approximate, but adequate for design purposes. The results indicated a reaction rate that was second order in bitumen content, with an activation energy of about 17 to 20 kcal/gmol.

Data for the boiling point distribution of the products was consistent with a change of mechanism from vaporization to pyrolysis as the samples are heated. Higher …

Electrochemical Evaluation Of Zinc Electrolyte, Rajesh Kumar Singh

Doctoral Dissertations

"The polarization characteristics of acidified zinc sulfate electrolyte with varying solution chemistries were examined by cyclic voltammetry. An attempt was made to correlate the polarization results with the morphological and current efficiency data in order to develop a better understanding of the more fundamental aspects of impurity and additive behavior during the zinc electrodeposition process.

A statistical screening design program was conducted to determine the effects of certain operating parameters on the nucleation potential of zinc from sulfate electrolyte. The variables studied included: solution temperature, H₂SO₄ and Zn concentration, and scan rate. The solution temperature was found to be the …

Mass Transport Considerations In Electrometallurgical Reactions, Jose Rolando Sami Cuzmar

Doctoral Dissertations

"The research program described is divided into three segments. In the first part, the morphology and kinetic studies of Cd²⁺ removal from ZnSO₄ solutions using Zn dust as a reducing agent are presented. In the absence of impurities, the morphology of the Cd deposit shows the formation of two-dimensional or leaf-like dendrites capable of interlocking and forming agglomerates or balls. The size and strength of the agglomerates depend on the initial Cd²⁺ concentration to Zn metal surface area ratio, the rate of Cd ²⁺ removal, and the reactor geometry. The presence of additives, like Cu²⁺ and …

Development Of Dynamic Testing Machine For Laboratory Modeling Of The Rock Fracturing Phenomenon, Mohammad Ali Moghaddass Zadeh Kermani

Theses

The purpose of this thesis is to develop a dynamic testing machine for laboratory modeling of the rock fracturing phenomenon. Bearing stratum fracturing is a construction difficulty which occurs when end-bearing piles are driven to weak rock or weathered sound rock. It is a pile group effect and can result in significantly less pile carrying capacity than the final driving resistance would normally indicate.

A linear scaling factor was derived to establish similitude between the laboratory apparatus and field conditions. This scaling factor is approximate and was used for overall sizing of the apparatus and its components. A more exact …

Negative Corona Current Characteristics Of An Electric Wind System, Aviti Kadete

Tanzania Journal of Engineering and Technology (TJET)

The corona current characteristics of an electric wind system are investigated. First a brief summary of the negative point to plate corona mechanism and characteristics are presented. Then empirical equations for corona currents of an electric wind system are derived. Current waveform characteristics are also discussed. The effects of placing parallel rods in between a point-plate electrode gap to the corona currents are highlighted.

The Eccentric Disc Pitter Planter-A Soil Conservation Tillage Tool For Mechanized Farming., J Dumelow

Tanzania Journal of Engineering and Technology (TJET)

A planting technique which could enhance agricultural production is presented. The Edip planting technique which is discussed has low capital and operating costs. It also has reasonable and reliable yields as well as providing effective moisture and soil conservation.

Engineer Education: Disciplinary Preferences In The Faculty Of Engineering University Of Dar Es Salaam, S Mosha

Tanzania Journal of Engineering and Technology (TJET)

Most practising engineers can hardly recall the days they had to make up their minds on whether engineering was their chosen career. This decision may have been approached with ignorance and very high expectations. Later after registering in a Faculty of Engineering the freshman was given a chance to choose a department; sometimes this had already been done for him by his sponsors so all he had to do was to walk into the preselected department.

A generation later, University entrants are faced with a similar predicament. This paper high-lights the procedures involved and proceeds to recommend the necessary fundamental …

Hydraulic Rams For Rural Water Supply Schemes In Selected Areas In Tanzania, T Mbwette

Tanzania Journal of Engineering and Technology (TJET)

This paper presents one of the many efforts made by the Faculty of Engineering and the Institute of Production Innovation of the University of Dar es Salaam towards the realization of the International Water Supply and Sanitation Decade. Special reference is made to the use of hydraulic rams along with some simple water treatment methods. Besides the account of theoretical and practical work done to-date in the field of water supply, a further evaluation of the theoretical model presented is recommended so as to enable a judgement of the present hydraulic ram designs to be done. Tests on a typical …

A Light Transmission Model For Biological Materials, R. A. Cavaletto, Shrinivasa Upadhyaya, Michael O'Brien

BioResource and Agricultural Engineering

This paper describes a model to predict light transmission in biological materials. The model can be used for any shaped sample. Scattering and absorption coefficients are used in the model and may be varied throughout the sample, thus allowing both uniformly distributed and concentrated defects to be modelled.

Guarding Of Table Saws With Light Beams: The Light Guard Concept, R. A. Cavaletto, M. S. Kaminaka, C. M. Zahner

BioResource and Agricultural Engineering

This paper describes a unique type of psychological safety guard for hazardous tools such as table saws, presses. and other tools with areas and components which are dangerous to human fingers, hands, and limbs. It is not a piece of hardware but rather a shalt of light which defines a danger zone around the saw blade or cutting area.

Designing And Installing Radiant Barrier Systems, Florida Solar Energy Center, Philip W. Fairey

FSEC Energy Research Center®

A radiant barrier system is, in general, a layer of foil facing an airspace, installed in the envelope of a building. Such systems are very effective in impeding radiant heat transfer and consequent heat gain, especially in southern residences. Before designing and installing a radiant barrier system, you should become familiar with the concept of radiant energy transfer. Design Note 6, Radiant Energy Transfer and Radiant Barrier Systems in Buildings, is required reading if you are not familiar with this concept.

Load Flow And Contingency Analysis In Power Systems, Kianfar Sorooshian

Dissertations and Theses

A load flow and contingency analysis program for secure design, planning and operation of power systems. Depending on the application either Newton-Raphson or Fast-Decoupled method is employed to solve the load flow. Fault analysis is done by Z bus method. Contingency analysis may be done following the load flow solution by Fast-Decoupled method. The program is also interfaced with a graphic system which displays a single line diagram of the system on the graphic screen along with relevant data and informs the operator of any change by flashing the faulted bus or the line outage.

Acuta Enews December 1984, Vol. 13, No. 12

ACUTA Newsletters

In This Issue

CABLING SYSTEMS FOR THE TELECOMMUNICATIONS EXPLOSION

PARTY LINE

GETTING OVER YOUR TELEPHONE HANG-UPS

POTPOURRI

A Review And Analysis Of Pile Design, David L. Allen

Kentucky Transportation Center Research Report

A review of lateral load design of piles is presented. It appears many different methods and allowable lateral loads are permitted by the states. One particular method is discussed in detail, and from that method two charts are presented that relate pile deflection to lateral load. Recommendations are given on design criteria for lateral loads.

A review of allowable axial stresses is also presented. The results of a brief finite element analysis of pile tip settlement versus load for various conditions are also presented. These results are compared to data obtained from the literature. Recommendations on maximum allowable axial stress …

Evaluation Of Durable Crosswalk And Stopbar Marking Materials (Interim Report), Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

The objective of this study is to find the most cost-effective durable marking material to provide long-lasting stop bars and crossbars. Three materials were tested: 1) 3M Stamark tape, 2) Prismo preformed tape, and 3) extruded thermoplastic. The evaluation concerned the durability, reflectivity, and appearance of the materials. Test installations have been in place for about 18 months, and this interim report summarizes findings for that period. The evaluation will continue for another 18 months, and recommendations will be presented in a final report.

Based on current evaluations, the extruded thermoplastic material would be considered the most cost-effective material for …

Evaluation Of Durable Lane Delineation Materials (Interim Report), Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

The objective of the study is to evaluate the cost-effectiveness of available marking materials by means of field tests and to develop a policy for material selection of lane delineation based on these tests. Materials tested included: 100 percent solid epoxy paint, polyester paint, extruded thermoplastic, 3M Stamark tape, 3M Bisymmetric tape, EPOFLEX, solvent epoxy paint, and chlorinated rubber paint. Most test installations have been in place for over two years, and this interim report summarizes findings for that period. The evaluation will continue for another 18 months with recommendations presented in a final report.

Based on current data, expanded …

Pavement Management In Kentucky, Gary W. Sharpe, Robert C. Deen, Herbert F. Southgate, Rolands L. Rizenbergs, James L. Burchett

Kentucky Transportation Center Research Report

The principal objective of this paper is to summarize current pavement management activities in Kentucky. Early pavement management activities generally were decentralized (involving a number of transportation functions such as planning, design, construction, maintenance, and research) and involved long-term monitoring for skid resistance and ride quality (roughness).

Current pavement management activities may be categorized by evaluation, project selection, and development of recommendations for pavement rehabilitation strategies. Pavement evaluation activities at the statewide system level typically involve assessments of ride quality (ridesbility index) and estimated pavement serviceability, skid resistance, visual condition ratings, and the accumulation of traffic volumes and pavement fatigue. …

Irish H & V News

Building Services Engineering

No abstract provided.

Application Of Combined Jointed Media And Discrete Slip Plane Characteristics To Subsidence Predictions, David W. Basinger

Theses and Dissertations

This thesis presents an application of a numerical formulation incorporating the effects of joints, cracks, and fractures to a soil subsidence predictions problem, and the extension of that formulation to combined discrete slip planes and jointed media continua formulations. The results obtained are compared to each other and to a physical centrifuge simulation performed previously on the same problem.

The Oxidation Of Dilute Alloys Of Magnesium In Aluminium, Hollis P. Leighly, A. Alam

Materials Science and Engineering Faculty Research & Creative Works

The oxide layers developed during the oxidation of aluminum alloys containing 500 and 1000 PPM of magnesium at 850K were examined with the aid of electron spectroscopy for chemical analysis. The magnesium content of the oxide layers was relatively high because of the preferential depletion of the magnesium atoms from the base alloys. Near the outer surfaces of the oxide layers, spinel (MgAl2O4) was the predominant magnesium-bearing compound. At depth, MgO was more dominant. The preferential depletion of magnesium from the alloys injected vacancies into the material. This led to the formation of defect clusters. The presence of these defect …

Solution To Eigenvalue Problems Of Antisymmetric Cross-Ply And Antisymmetric Angle-Ply Laminated Plates Using Affine Transformations, Zaffir A. Chaudry

Theses and Dissertations

Using affine transformations and suitably recasting the buckling vibration differential equations, the eigenvalue problem of anti-symmetric cross-ply and antisymmetric angle-ply laminated rectangular plates has been reduced to a function of two strong material constants, the generalized rigidity ratio, whose range is in the closed interval from 0 to 1, and the ratio of principal lamina stiffness. With the reduction in number of constants an exhaustive parameter study of buckling and vibration solution trends, is possible. The buckling coefficients decrease with decreasing value of generalized rigidity ratio for both antisymmetric cross-ply and antisymmetric angle-ply laminates. For a given aspect ratio, and …

Study Of Longitudinal Landing Flying Qualities Evaluation Using Pilot Model Theory, Eric D. Didomenico

Theses and Dissertations

Control Anticipation Parameter (CAP), used in MIL-SPEC-8785C as a longitudinal handling qualities criterion does not adequately distinguish between different flight phases. Recent flight test data from the Landing Approach Higher Order Systems (LAHOS) study further indicate the inadequacy of the second order approximations for higher order longitudinal landing flying qualities. Nine Aircraft that fall within the Level 1 boundary reveal pilot ratings ranging from 1.5 to 10 (Cooper/Harper). These nine aircraft are studied by combining their longitudinal dynamics with pilot modelling to examine a better method of landing flying quality prediction and evaluation. Pilot model theory (cross-over pilot model) is …

Test 1550: Steiger Panther Iv Sm-325 Diesel 20-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Reliability Verification Using Service Loads, Brent W. Hall, Andrzej S. Nowak

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Non-Uniformly Compressed Stiffened Elements, Venkatakrishnan Kalyanaraman, P. Ramakrishna

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Cold Formed Steel In Folded Truss Decks, Robert W. Dannemann

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Local Buckling In Curved Box Members, Issam E. Harik, Raghuram Ekambaram

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Influence Of Manufacturing Technology On Cold Formed Structural Members, George T. Halmos

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

How To Ensure Quality Construction In Light Steel Framing, Patrick J. Boyd, J. S. Traw, D. R. Wootton, Calvin Robert Clauer

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.