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Measurement and Analysis of Indoor Air Quality Conditions

Description: More than 80% of the people in urban regions and about 98% of cities in low and middle income countries have poor air quality according to the World Health Organization. People living in such environment suffer from many disorders like a headache, shortness of breath or even the worst diseases like lung cancer, asthma etc. The main objective of the thesis is to create awareness about the air quality and the factors that are causing air pollution to the people which is really important and provide tools at their convenience to measure and analyze the air quality. Taking real time air quality scenarios, various experiments were made using efficient sensors to study both the indoor and outdoor air quality. These experimental results will eventually help people to understand air quality better. An outdoor air quality data measurement system is developed in this research using Python programming to provide people an opportunity to retrieve and manage the air quality data and get the concentrations of the leading pollutants. The entire designing of the program is made to run with the help of a graphical user interface tool for the user, as user convenience is considered as one of the objectives of the thesis. A graphical user interface is made for the user convenience to visualize graphically the data from the database. The designed system is tested and used for the measurement and analysis of the outdoor air quality. This data will be available in the database so it can be used for analyzing the air quality data for several days or months or years. Using the GrayWolf system and the designed outdoor air quality data measurement system, both the indoor and outdoor air quality was measured to analyze and correlate.
Date: August 2016
Creator: Chidurala, Veena
Partner: UNT Libraries

AC 2007-1844: An Innovative Mechanical and Energy Engineering Curriculum

Description: This paper discusses the addition of a new Department of Mechanical and Energy Engineering at the University of North Texas (UNT). Those involved see the curriculum for this new program as a new model of engineering education that parallels the innovations of UNTs current Learning to Learn (L2L) project-oriented concept course with the addition of innovative approaches for mechanical engineering and emphasis on energy engineering education.
Date: 2007
Creator: Michaelides, Efstathios & Mirshams, Reza
Partner: UNT College of Engineering

ASME Material Challenges for Advanced Reactor Concepts

Description: This study presents the material Challenges associated with Advanced Reactor Concept (ARC) such as the Advanced High Temperature Reactor (AHTR). ACR are the next generation concepts focusing on power production and providing thermal energy for industrial applications. The efficient transfer of energy for industrial applications depends on the ability to incorporate cost-effective heat exchangers between the nuclear heat transport system and industrial process heat transport system. The heat exchanger required for AHTR is subjected to a unique set of conditions that bring with them several design challenges not encountered in standard heat exchangers. The corrosive molten salts, especially at higher temperatures, require materials throughout the system to avoid corrosion, and adverse high-temperature effects such as creep. Given the very high steam generator pressure of the supercritical steam cycle, it is anticipated that water tube and molten salt shell steam generators heat exchanger will be used. In this paper, the ASME Section III and the American Society of Mechanical Engineers (ASME) Section VIII requirements (acceptance criteria) are discussed. Also, the ASME material acceptance criteria (ASME Section II, Part D) for high temperature environment are presented. Finally, lack of ASME acceptance criteria for thermal design and analysis are discussed.
Date: July 1, 2013
Creator: Sabharwall, Piyush & Siahpush, Ali
Partner: UNT Libraries Government Documents Department

A Study of Vertical Gas Jets in a Bubbling Fluidized Bed

Description: A detailed experimental study of a vertical gas jet impinging a fluidized bed of particles has been conducted with the help of Laser Doppler Velocimetry measurements. Mean and fluctuating velocity profiles of the two phases have been presented and analyzed for different fluidization states of the emulsion. The results of this work would be greatly helpful in understanding the complex two-phase mixing phenomenon that occurs in bubbling beds, such as in coal and biomass gasification, and also in building more fundamental gas-solid Eulerian/Lagrangian models which can be incorporated into existing CFD codes. Relevant simulations to supplement the experimental findings have also been conducted using the Department of Energy’s open source code MFIX. The goal of these simulations was two-fold. One was to check the two-dimensional nature of the experimental results. The other was an attempt to improve the existing dense phase Eulerian framework through validation with the experimental results. In particular the sensitivity of existing frictional models in predicting the flow was investigated. The simulation results provide insight on wall-bounded turbulent jets and the effect frictional models have on gas-solid bubbling flows. Additionally, some empirical minimum fluidization correlations were validated for non-spherical particles with the idea of extending the present study to non-spherical particles which are more common in industries.
Date: January 18, 2011
Creator: Ceccio, Steven & Curtis, Jennifer
Partner: UNT Libraries Government Documents Department

Commercialization of Turbulent Combustion Code CREBCOM for Chemical Industry Safety

Description: This program developed the Kurchatov Institute’s CREBCOM (CRiteria and Experimentally Based COMbustion) code to the point where it could be commercialized and marketed for the special applications described above, as well as for general purpose combustion calculations. The CREBCOM code uses a different approach to model the explosion phenomenon. The code models, with full 3D gas dynamics, the development of an explosion in three characteristics regimes: a) slow flames, b) fast flames, and c) detonation. The transition from one regime to another is governed by a set of empirical criteria and correlations. As part of the commercialization, the code was validated with the use of experimental data. The experimental data covered a range of thermodynamic initial conditions and apparatus scale. Proprietary experimental data were provided to the Kurchatov Institute by the DuPont for this purpose. The flame acceleration and detonation data was obtained from experiments in methane and oxygen enriched air mixtures carried out in two vessels with diameters of 20 and 27 cm. The experimental data covers a wide spectrum of initial temperature (20-525C) and pressure (1-3 atm). As part of this program, the Kurchatov Institute performed experiments in a 52 cm vessel in mixtures of methane-air at room temperature and pressure to be used in the validation of the code. The objective of these tests was to obtain frame acceleration data at a scale close to that found in actual industrial processes. BNL was responsible for managing the DOE/IPP portion of the program, and for satisfying DOE reporting requirements. BNL also participated in an independent assessment of the CREBOM code. DuPont provided proprietary experimental data to the Kurchatov Institute on flame acceleration and detonation in high temperature methane and oxygen enriched air mixtures in addition to the matching fund. In addition, DuPont also supplied to KI instrumentation for ...
Date: June 30, 2007
Creator: Rohatgi, Upendra
Partner: UNT Libraries Government Documents Department


Description: A remote metallographic facility is in operation at Argonne National Laboratory. Techniques relative to better contamination control and equipment operation were developed. The techniques used for microscopic examination of irradiated materials were standardized with variations only in the final polishing steps, and detailed procedures are given for several alloys. The procedures used for macroscopy vary from sample to sample, and new procedures are developed as required to suit each particular problem. (auth)
Date: September 1, 1961
Creator: Carlander, R.
Partner: UNT Libraries Government Documents Department


Description: Two methods were evaluated for removal of 1 to 5 kilowatts from a 1-in.- diam. by 10 in. long bomb to be (W-7405-eng-261. 8O(ph OTS); 70(mf OTS). maintained at 250 to 300 deg C. Conductance control, varying the composition of a helium--air mixture in a 8 mil annulus to give a controlled conduction heat transfer resistance, gave a simple, smooth, flexible control method. Use of water sprayed into air gave the required range of heat fluxes, but sometimes gave uncontrollable instabilities due to progressive vapor binding. (auth)
Date: June 16, 1958
Creator: Holmes, J.M.
Partner: UNT Libraries Government Documents Department


Description: Low-cycle fatigue tests were conducted by tension-compression until rupture, on a 2024-T3 aluminum alloy sheet. Initial crack sizes and orientations in the fatigue specimens were found to be randomly distributed. Acoustic emission was continuously monitored during the tests. Every few hundred cycles, the acoustic signal having the highest peak-amplitude, was recorded as an extremal event for the elapsed period. This high peak-amplitude is related to a fast crack propagation rate through a phenomenological relationship. The extremal peakamplitudes are shown by an ordered statistics treatment, to be extremally distributed. The statistical treatment enables the prediction of the number of cycles left until failure. Predictions performed a-posteriori based on results gained early in each fatigue test are in good agreement with actual fatigue lives. The amplitude distribution analysis of the acoustic signals emitted during cyclic stress appears to be a promising nondestructive method of predicting fatigue life.
Date: May 1, 1980
Creator: Baram, J. & Rosen, M.
Partner: UNT Libraries Government Documents Department

Quarterly Summary Report April-June 1978 Process for Cleaning and Removal of Sulfur Compounds From Low Btu Gases

Description: In this phase of work the Process Development Unit (PDU) is to be remodeled by incorporation of appropriate subsystems to permit operation in continuous process mode. The PDU will be operated for a period of time sufficient to demonstrate process viability.
Date: July 1, 1978
Partner: UNT Libraries Government Documents Department