Engineering Commons^™

Characteristics Of The Background Emission Spectrum From A Miniature Inductively-Coupled Plasma, Richard N. Savage, G. M. Hieftje

Materials Engineering

The spectral characteristics of the background radiation emitted by a miniature inductively-coupled plasma (i.c.p.) are carefully examined and methods for reducing undesirable features discussed. The complex nature of the background emission spectrum for the mini-i.c.p. indicates that careful line selection criteria and background correction procedures should be employed. Extending the torch coolant tube to the bottom of the region being observed in the plasma proved to be the most effective method for reducing undesirable spectral band features. Acute changes in background emission levels with r.f. power and nebulizer gas flow rates emphasize the need for careful control of these parameters …

The Performance Of Crossed-Vane Swirl Meters, H. L. Lee, William W. Durgin

Office of the Provost Scholarship

Vortimeters consisting of vanes rotating about pipe axes are frequently used to indicate the swirl present in pump columns and feedlines from sumps and in piping networks. Since the design of such devices varies widely, the study described herein was undertaken to identify salient design parameters and to evaluate a device designed according to information available in the literature.

An apparatus which could produce known amounts of angular momentum in a pipeline was verified by direct measurement of axial and tangential velocity profiles. By using the assumption that a vortimeter, with vanes spanning only the rotational core, responded to an …

Thermal Gasification Of Densified Sewage Sludge And Solid Waste, Samuel A. Vigil, George Tchobanoglous

Civil and Environmental Engineering

The disposal of sewage sludge in an economic and environmentally acceptable manner is a problem common to all communities that have municipal wastewater treatment facilities. Similarly, all communities are faced with the disposal of increasing quantities of solid waste. The co-disposal of sludge and solid waste in a common facility is a potential solution to both of these problems. The results of an experimental program to verify the feasibility of the gasification process for the co-disposal of densified sludge and source separated solid waste are presented in this paper.

Lower Mode Response Of Circular Cylinders In Cross-Flow, William W. Durgin, P. A. March, Paul J. Lefebvre

Office of the Provost Scholarship

Transverse amplitude responses of a circular cylinder in cross-flow were determined as a function of reduced velocities for a variety of spring constants and damping coefficients. Maxima were found at reduced velocities of 5 and 16, and were of comparable amplitude. The first resonance, designated the "fundamental mode, " was due to normal vortex street excitation of the spring-mass system. The second resonance, designated the "lower mode," occurred when the natural frequency was approximately one-third of the normal vortex shedding frequency. By assuming that the driving force was sinusoidal, it was possible to evaluate the lift coefficients at resonance. Lift …

Electronic Fuel Injection Techniques For Hydrogen Powered I.C. Engines, Art Maccarley, W. D. Van Vorst

Electrical Engineering

Numerous studies have demonstrated the advantages of hydrogen as a fuel for Otto Cycle engines due to high thermal efficiency and low exhaust pollutant levels. Characteristic of hydrogen engine operation using premixed intake charge formation is a problem of pre-ignition resulting in an intake manifold “backfire”. Additional problems include high NO_x production when using certain equivalence ratios and power output degradation due to low fuel energy/volume density.

Techniques for direct and port fuel injection are discussed as means for overcoming these problems. Emphasis is placed on the need for total engine control, integrating control of fuel injection, ignition timing, …

An Integrated System Employing Alternate Technologies For Liquid And Solid Waste Managment For Intermediate And Small Communities, George Tchobanoglous, John E. Colt, Robert G. Smith, Samuel A. Vigil

Civil and Environmental Engineering

Over the past 20 years , a variety of alternative, and in many cases innovative, technologies have been proposed for use in waste management systems. If alternative technologies are to be adopted they must, 1) be technologically feasible, 2) minimize the use of energy and resources, 3) maximize the recovery of the energy and nutrients contained in wastewater, 4) be cost-effective, and 5) not be unnecessarily disruptive of the existing order in their implementation. Although a number of the proposed technologies have met some or all of these requirements , few of them have been widely adopted. The principal reason …

Application Of Packed Bed Gasifiers To The Reduction Of Solid Wastes And The Recovery Of Energy, Samuel A. Vigil, George Tchobanoglous, Edward D. Schroeder

Civil and Environmental Engineering

No abstract provided.

Careers In Air Pollution Control, Harold M. Cota

Civil and Environmental Engineering

No abstract provided.

University Programs In Air Pollution Control: Review And Outlook, August T. Rossano, Harold M. Cota

Civil and Environmental Engineering

From the inception of the National Air Pollution Control program, the U. S. Congress has been mindful of the need and importance of adequate manpower. The challenging technical problems which lie ahead in enforcement, monitoring, testing and research can be effectively dealt with only by individuals with specialized knowledge, skills and experience. In this paper the authors look at undergraduate and graduate training that is being carried out, employment opportunities and the way these may change in the future. A recently completed survey of college level air pollution training in the United States and Canada is included in the report.

Enhancement Of Pneumatic Nebulization Efficiency Through Application Of An Electric Field, Richard N. Savage, G. M. Hieftje

Materials Engineering

A novel technique is described for reducing the size of aerosol droplets produced by a pneumatic nebulizer of the kind commonly used in flame or plasma spectrometry. The technique involves the application of an electric field to the tip of the nebulizer, resulting in an induced surface charge on the liquid being nebulized. In turn, the surface charge reduces the liquid's surface tension and results in the generation of a finer aerosol. In this study, the effect of the electric field is quantified in terms of the spatial dispersion and size distribution of aerosol droplets formed in the presence and …

A Review Of Manpower Training And Future Directions In Air Pollution Control At Universities, August T. Rossano, Harold M. Cota

Civil and Environmental Engineering

No abstract provided.

Electronic Fuel Injection Techniques For Hydrogen Fueled Internal Combustion Engines, Carl Arthur Maccarley

Electrical Engineering

Numerous studies have demonstrated the advantages of hydrogen as a fuel for Otto Cycle engines due to high thermal efficiency and low exhaust pollutant levels. Characteristic of hydrogen engine operation using pre-mixed intake charge formation is a problem of pre-ignition resulting in an intake manifold "backfire." Additional problems include high NO production when using certain equivalence ratios and power output degradation due to low fuel energy/volume density.

Techniques for direct and manifold fuel injection are discussed as means for overcoming these problems. Emphasis is placed on the need for total engine control, integrating control of fuel injection, ignition timing, intake …

Environmental Manpower And Training, Harold M. Cota

Civil and Environmental Engineering

No abstract provided.

Laser Doppler Anemometry For Flow Measurement, William W. Durgin, Lawrence C. Neale

Office of the Provost Scholarship

Laser doppler anemometers are non-invasive, linear, and inherently precise. Calibration, in the usual sense, is not necessary; length and frequency measurements suffice to establish velocity at a spatial point. Measurements were made at points in the cross-sections of two square ducts containing water flow. The points were selected in conformance with a numerical integration scheme to be used for volumetric flow rate determination from the velocity measurements. The experiments were performed in a primary calibration facility at flows up to 1.25 m³/sec using ducts with sides 46 and 92 cm. The anemometer, operating in forward scatter differential mode …

Air Pollution Control Training In Colleges And Universities: A Status Report For The United States And Canada, Harold M. Cota

Civil and Environmental Engineering

The APCA Education and Training Committee surveyed air pollution training at colleges and universities in the United States and Canada in 1975. There were 197 full-time faculty teaching air pollution courses at 75 schools. Graduates from these programs are finding meaningful work in both the public and private sector. Financial support is briefly discussed.

Wave Induced Pressures On Submerged Plates, William W. Durgin, Jong C. Shiau

Office of the Provost Scholarship

The prediction of forces, or more precisely, the pressure distributions, experienced by submerged structures due to the passage of gravity waves has become important with the advent of large offshore structures. If the size of a structure is small compared to the wavelength then the forces can be evaluated by the assignment of suitable drag and inertia coefficients using an approach similar to that of Morison (6) in which case it is necessary to determine the coefficients experimentally for any given geometry (2). If the size of the structure is a significant fraction of the wavelength, the preceding method is …

Problems Of Measurement In The Environmental Field, Harold M. Cota

Civil and Environmental Engineering

No abstract provided.

Air Pollution Control Training In Colleges And Universities In The United States, Harold M. Cota

Civil and Environmental Engineering

A nationwide survey of air pollution control training efforts in the United States at colleges and universities was carried out for the S-ll Education and Training Committee, Air Pollution Control Association. Information from 91 schools having four year or graduate programs and five community colleges was received. Questions include type of course work, backgrounds of participating faculty and students, and eventual placement. At the present time about 70% of those in training are graduate students. It was found that most students taking initial employment in air pollution control activities had the M.S. degree. Recommendations for updating this information are made.

On The Phenomenon Of Vortex Street Breakdown, William W. Durgin, Sture K.F. Karlsson

Office of the Provost Scholarship

A von Kármán vortex street generated in the usual way was subjected to a deceleration, thereby changing the ratio of longitudinal to lateral spacing between the vortices. Distortion of the individual vortices followed which resulted in annihilation of concentrated vortex regions and creation of a stationary wake flow. This wake flow was itself dynamically unstable and developed into a new vortex street of a different frequency from the initial one. The breakdown of the initial vortex street is qualitatively explained by considering the convection of a concentrated vortex region due to the motion imposed by all the other vortices.

Decomposition Of Diulte Hydrogen Peroxide In Alkaline Solutions, Harold M. Cota, T. Katan, M. Chin, F. J. Schoenweis

Civil and Environmental Engineering

No abstract provided.

Worldwide Training In Air Pollution Control, Harold M. Cota

Civil and Environmental Engineering

A survey of academic training in air pollution control was recently conducted for the APCA Education Council. Questionnaires were sent to faculty at over 200 universities in the United States and 150 universities around the world. This paper lists the schools which completed the questionnaire and includes the number of both undergraduate and graduate courses available, the academic department, and the range of research projects presently underway. The findings indicate that air pollution is a subject being taught worldwide. Most schools predict that their current level of instruction will not change in the next five years. Additions and corrections are …

Design Parameters For Fuel Batteries Operating In A Zero G Field, A. P. Hardt, Harold M. Cota, J. L. Fick, T. Katan

Civil and Environmental Engineering

Some design parameters of a hydrazine-oxygen fuel battery operating in a zero G field are described in a digital computer programming treatment. The power balance for a battery employing a gas-producing electrode and an electrolyte pump is treated; optimum power densities and flow rates are established.