Engineering Commons^™

Experimental Investigations Of Bio-Syngas Production Using Microwave Pyrolysis Of Uae’S Palm Date Seeds, Mahmmoud Muhammed Syam

Mechanical Engineering Theses

From the start of the industrial revolution, the continued need for energy has been the most crucial issue in human history. An energy crisis started at the beginning of the 1970s when the number of machines, which became an essential part of our life, increased rapidly. Scientists made a huge effort to discover new sources of energy, with ‘biomass’ being one of the main focuses of researchers as a new renewable source of energy. In this thesis, a non conventional method of heating, using microwave power in a pyrolysis process of biomass waste from palm trees (Allig’s date seeds) for …

A Discovery Of Social Impact Categories For The Sustainable Design Of Engineered Products And Their Consideration By Industry Professionals, Andrew Taylor Pack

Theses and Dissertations

Sustainable design is often practiced and assessed through the consideration of three essential areas: economic sustainability, environmental sustainability, and social sustainability. For even the simplest of products, the complexities of these three areas and their trade-offs cause decision making transparency to be lost in most practical situations. Additionally, the models and tools available to consider social sustainability are severely underdeveloped. This thesis is separated into three parts: 1) a design tool to consider all three aspects of sustainability simultaneously, 2) a literature survey to characterize social impact as it relates to products, and 3) interviews with engineering professionals regarding how …

Low Temperature Multi Effects Desalination-Mechanical Vapor Compression Powered By Supercritical Organic Rankine Cycle, Eydhah Almatrafi

USF Tampa Graduate Theses and Dissertations

Utilizing low grade heat sources such as geothermal, solar or waste heat has received a high attention in recent years. A lot of research has discussed using Organic Rankine Cycle (ORC) as subcritical or supercritical in power generation. However, very few studies extend their research in utilizing ORC in other applications such as desalination. For reverse osmosis (RO) desalination, which is considered a membrane technology, the use of supercritical-ORC in low grade heat sources is more favorable than subcritical-ORC. Thus, studies of utilizing either subcritical-ORC or supercritical-ORC for thermal desalination that use power and heat from Rankine cycle are rare …

Plenum-To-Plenum Heat Transfer Characteristics Under Natural Circulation In A Scaled-Down Prismatic Modular Reactor, Salman Mohammed Alshehri

Doctoral Dissertations

“Gas-cooled reactor (GCR) is being developed under the Next Generation Nuclear Plant Program (NGNP) in nuclear engineering studies. As the world searches for an energy source with high energy density, clean, abundant, and storable nature to avoid global warming issues, GCR seems to be a promising solution, particularly the possibility of producing hydrogen. Studying and developing the safety analysis and GCR technologies are required for the optimum design and safety of GCR system. Multiphase Reactors Engineering and Applications Laboratory (mReal) at Missouri University of Science and Technology (S&T) has developed a natural convection heat transfer test facility with one riser …

Design And Testing Of A Wind Energy Harnessing System For Forced Convective Drying Of Grain In Low Wind Speed, Warm And Humid Climates, Francis Akumabi Agbali

Theses and Dissertations--Biosystems and Agricultural Engineering

Forced convective drying using a wind turbine mechanically connected to a ventilation fan was hypothesized for low cost and rapid grain drying in developing countries. The idea was tested using an expandable wind turbine blade system with variable pitch, at low wind speeds in a wind tunnel. The design was based on empirical and theoretical models embedded in a graphical user interface (GUI) created to estimate airflow-power requirements for drying ear corn. Output airflow (0.0016 - 0.0052 m³kg^-1s^-1) increased within the study wind speed range (2.0 - 5.5 m/s). System efficiency peak (8.6%) was …

Modelling Of Aerodynamic Process For Coal Waste Dump Located In Geodynamically Dangerous Zone, Elena Vishnevskaya, Alexander Kobylkin, Valeriya Musina, Andrian Batugin, Vladimir Ponomarev, Oksana Vorobyeva

Publications

Previously made evaluations show confinement of fire coal waste dumps to geodynamically dangerous zones which in this work are considered as borders of active blocks of the earth crust. According to the hypothesis under development, when disposing the dumps in geodynamically dangerous zones (GDZ), which have a high penetrating, aerodynamic relation of the dumps with the environment occurs, making the dumps firing possible. Firing of the dumps inflicts environmental, social and material damage. This research is aimed to study possible mechanism of gas mass transfer through GDZ into the body of dump on the base of computer modeling of aerodynamic …

Dynamic Discrepancy Reduced Order Modeling For Fischer-Tropsch Synthesis Over Cobalt-Based Catalyst, Jose Miguel Bohorquez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Advances in carbon capture techniques and demands in alternative fuel sources have increased over the past couple of decades. The Fischer-Tropsch Synthesis (FTS) provides a viable way to produce hydrocarbons from natural gas, coal, CO₂, or biomass. However, current comprehensive models for FTS encompass large number of reacting species, readsorption and conversion of primary products, surface intermediates, and coverage-dependent reaction rates. To accurately predict the products obtained through the process a reduced order model has been developed. By reducing the number of parameters of an existing comprehensive model, uncertainty is introduced. The uncertainty can be quantified by using …

Hemodynamic Interference Of Serial Stenoses And Its Impact On Ffr And Ifr Measurements, Siyeong Ju, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

The hemodynamic interference of serial stenoses poses challenges for identifying the functional severity using the fractional flow reserve (FFR) method. The instantaneous wave-free ratio (iFR), i.e., the distal-to-proximal pressure ratio at 75% of diastole, was recently proposed to overcome the disadvantages of the FFR. However, the underlying mechanism remained ambiguous due to the lack of quantitative definition of hemodynamic interference. The objective of this study is to quantitatively define the hemodynamic interference and then examine its role on the FFR and iFR measurements. Pressure distributions, velocity fields, and Q-criterion which identifies vortices, were obtained through the computational fluid dynamics (CFD) …

Solar Tracker Renewable Energy, Stephanie Christie, Annabeth Helmly, Matthew Smith, Katrina Vaughan

ENgaging Educators in Renewable enerGY (ENERGY): Lesson Plans & Slideshows (2017-2019)

No abstract provided.

3d Printing In Low Resource Healthcare Settings: Analysis Of Potential Implementations, Alenna Beroza

Dissertations, Master's Theses and Master's Reports

3D printing has gained significant momentum in the past ten years, and its unique advantages make it especially ideal for use in low resource healthcare settings, where many designs have already been successfully implemented. Yet, little has been studied on how 3D printing can be sustainably and functionally implemented in low resource healthcare systems as a manufacturing practice. In this report, three business models are proposed for this implementation: In-House Operator, Independent Operator, and Print Farm. These models were then tested over four months in Kisumu county, Kenya, at two workshops and seven public hospitals. I worked with local medical …

Assessment Of Cooling And Heat Transfer Properties Of Quenchants With Matlab, Lemmy Meekisho, Rosa L. Simencio Otero, Jônatas M. Viscaino, D. Scott Mackenzie, George Totten, Lauralice C.F. Canale

Mechanical and Materials Engineering Faculty Publications and Presentations

There is ongoing interest for evaluating the potential of renewable base stocks, such as vegetable oils, to replace petroleum oils as metal quenchants. Perhaps the most critical part of this process is characterizing and comparing the cooling and heat transfer performance of potential quenchant candidates. In this work, cooling curves of two vegetable oils, palm oil and canola oil, were obtained along with a commercially available conventional and an accelerated petroleum quenchant using the so-called Tensi multiple thermocouple probe, with emphasis on the center probe emulating a small probe concept. The lumped-parameter approach was implemented in the MATLAB environment (Mathworks …

Quenchant Cooling Curves, Rewetting, And Surface Heat Flux Properties Of Vegetable Oils, Rosa L. Simencio Otero, Jônatas M. Viscaino, Jun Xu, Jianfeng Wu, George Totten, Lauralice C.F. Canale

Mechanical and Materials Engineering Faculty Publications and Presentations

Vegetable oils are currently used for biodegradable and renewable base stocks for quenchant formulation. However, there are relatively few references relating to their true equivalency, or lack thereof, comparative to the quenching performance of petroleum oil-based quenchant formulations. To obtain an overview of the variability vegetable oil quenching performance, the cooling curves and rewetting properties were determined, and the surface heat flux properties were calculated. The vegetable oils that were studied included canola, coconut, corn, cottonseed, palm, peanut, soybean, and sunflower oils. Cooling curves were obtained using the Tensi multiple-surface thermocouple 15 mm diameter by 45 mm cylindrical Inconel 600 …

Foil Thrust Bearing With Pocket Grooves And Tailored Bump Stiffness Distribution For Improved Static Performance, Nguyen Thao Latray

Mechanical and Aerospace Engineering Dissertations - Archive

Gas foil thrust bearing is one of few axial bearing options for high speed turbomachinery systems. Its advantages include low cost, light weight, generous allowance for component mis-alignment and runout. However, the bearing has low load carrying capacity comparing to other types such as rigid gas bearing and magnetic bearing. This work explores two non-traditional design aspects to improve gas foil thrust bearing’s static performance. The bearing bump foil is redesigned to tailor to the bearing pressure profile; hence induces a more uniform gas film thickness. Simulation using independent elastic foundation model predicts the new tailored bump foil thrust bearing …

Design Of A Portable Biogas Purification And Storage System, Anilkumar Kosna

Masters Theses

Biogas is produced from the decomposition of organic materials like manure, sewage sludge or crop fodders in anaerobic digesters. It consists mainly of 40 – 75 % of methane (CH₄), 15 – 60 % of carbon dioxide (CO₂) and trace amounts of other components. The principle constituents of biogas are similar to natural gas. Natural gas has 87 – 97 % of methane (CH₄) and 0.1 – 1 % of carbon dioxide. Natural gas is known to be an alternative fuel with a wide range of applications. The commercial purification technologies exist for large-scale …

Low Temperature Desiccants In Atmospheric Water Generation., Sunil Gupta

Electronic Theses and Dissertations

Surging global water demand as well as changes to weather patterns and over exploitation of natural water sources, such as ground water, has made potable water a critical resource in many parts of the World already – one rapidly heading towards a crisis situation. Desalination has been adopted as a solution – this is however energy intensive and impractical for most of the developing countries - those most in need of water. A renewable source of energy is solar thermal and solar photovoltaic. A plentiful source of water is the humidity in the atmosphere. This research is to push the …

Use Of Pv/T Panels To Meet The Building Loads Of Light Commercialized Buildings, Sadhvi Arora

Masters Theses and Doctoral Dissertations

This thesis deals with the analysis of a Photo Voltaic Thermal (PV/T) panel that is capable of producing simultaneously electric power and low-grade heat energy by absorbing the solar energy striking on its surface. A simple mathematical model is developed to estimate the electric power and heat energy gained by the PV/T panel. A water-to-water heat pump is employed that operates by absorbing the low-grade heat energy obtained from PV/T panel, in its evaporator, in order to produce high temperature hot water in its condenser. The high temperature hot water thus produced can be employed to meet the winter heating …

Ship-Port Interface : Analysis Of The Cost-Effectiveness Of Cold Ironing At Mombasa Port, Ronald Ssali

World Maritime University Dissertations

No abstract provided.

The Correlation Between Energy Cost Share, Human, And Economic Development Using Time Series Data From Australasia, Europe, North America, And The Brics Nations, Ryan Roberts, Josephine Kaviti Musango, Alan Colin Brent, Matthew K. Heun

University Faculty Publications and Creative Works

This paper investigates how a change in a region's energy cost share (ECS), a ratio of a region's energy expenditure as a fraction of its gross domestic product (GDP), affects the region's social and economic development. Nations from four regions of the world, namely Australasia, Europe, North America, and the BRICS nations (Brazil, Russia, India, China, and South Africa) were chosen for this study. Using time series data from the period of 1978 to 2010, the annual ECS of each country was compared to the year-on-year GDP change, as well as the components of the human development index (HDI). High …

Investigations Into The Airside Cooling Of A Heat Exchanger, David Vallet

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this study we investigate the air-side cooling of a flat-plate fin and tube heat transfer condenser with numerical simulations. A new design is proposed which utilises vortex generators to direct the flow in such a way as to remove some of the stagnant heated air that collects in the wake of the pipes. A comparative study of the proposed design and a standard tube and fin condenser is conducted by varying the air side entrance velocities. The Shear Stress Tension, SST $\kappa - \omega$ 2-equation turbulent model is used to solve the RANS model in ANSYS Fluent 18. The …

Design For Maintainability In Developing Communities—A Case Study On The Uros Islands, Thomas Barlow

Undergraduate Honors Theses

Designing products for developing communities has exposed many of the underlying assumptions that engineers from developed nations have during the design process. There has been much written about these underlying assumptions in order to create a better framework for designing for developing communities. One unexplored, yet important area is the universality of common maintainability principles used in developed countries when designing products used in developing communities. Such principles include: simplicity, diagnosability, standardization of parts, modular subassemblies, minimizing assembly and disassembly parts, labeling components, increased life of moving parts, manuals, and simplifying tools needed for repairs [1]–[3]. The purpose of this …

Solar Electric Immersion Heating Element Fabrication, Logan V. Kregness

Industrial and Manufacturing Engineering

Believing that cooking with flame is cheaper and more efficient than cooking with electricity, Ugandan citizens have exposed themselves to several health and safety risks, including major respiratory issues through harmful emissions, pollution, and the burning down of many homes. Even though solar electric cooking is cheaper and healthier than cooking with flames in the long run, many Ugandans lack the resources to invest in cooking with electricity.

The Solar Stove student research team, led by Dr. Pete Schwartz, partnered with Aid Africa to bring solar panels and prototype solar electric cooking units to villages in Uganda. Observing how their …

Increased Energy Yield Through Fast Pyrolysis: Empowering Malawian Villages, Diehl Mutamba

Undergraduate Honors Theses

Biomass contributes to several renewable energy technologies. This project will explore the use of fast pyrolysis to produce fuels by designing an apparatus for fast pyrolysis. Malawian people harvest firewood from the forests, which is a major contributor to deforestation. Furthermore, they convert some of it to charcoal with about 10-15% efficiency to sell to city dwellers. The project will enable herbaceous fuels to replace wood, increase charcoal yields and create new products. Firewood and charcoal produce smoke and carbon monoxide (CO) that compromises the villagers’ health.

This project will address deforestation problems, improve sustainability, decrease health hazards and improve …

Mechanical Team Final Design Report: Same Polytechnic College, Meghan L. Smith, Katie D. Nute, Long T. Hoang

Mechanical Engineering

The purpose of this document is to communicate the research, findings, and recommendations of the mechanical engineering team regarding the Same Polytechnic College project. This report includes a discussion of the design process utilized by the interdisciplinary team to construct preliminary building designs for both classroom and dormitory building modules. The mechanical team conducted testing using the wind tunnel to verify major building envelope design decisions. The following report also includes an explanation of the thermal testing that the team conducted to measure the thermal conductivity, diffusivity, and specific heat of bricks made to mimic those made locally in Same, …

Modelling Of Oxygen Diffusion In Cork, Swapnil Shivputra Rane

Theses

The primary objective of this project is to better understand gas diffusion through natural cork structures by comparing simulations of gas diffusion through natural cork to experimental measurements of oxygen gas diffusion through the same structure. The cork's internal structure is measured using x-ray computed tomography (CT). From the measured internal structure, a simple mapping is assumed converting the measured x-ray computed tomography images into a 3D map of local diffusion coefficient. Specifically, it is assured that the x-ray CT pixel value is inversely proportional to the diffusion coefficient of oxygen through the cork. A diffusion model for the cork …

A Numerical Model Of An Axial Wind Turbine, Andrew Liam Poland

UNLV Theses, Dissertations, Professional Papers, and Capstones

Since the beginning of the industrial revolution, there has never been more of a constant in the world than that of the demand for energy. For years a stable source has been fossil fuels, but with the growing impacts of global warming, it is important to look for renewable sources. Wind energy’s use has become more and more prevalent throughout the world.

This preliminary work runs through the creation of a three-dimensional numerical model of a conventional wind turbine that was created using ANSYS-Fluent© commercial software. This work provides the base wind turbine and a blade element and momentum theory …

Experimental Investigation Of Fischer-Tropsch Synthesis With A Modified Catalyst Support, Pawarat Bootpakdeetam

Mechanical and Aerospace Engineering Dissertations - Archive

Energy demand has been rapidly increasing in the last 30 years due to the population growth and high demand by industries. However, as natural energy sources are limited, they cannot meet this increased energy demand. Therefore, alternative energies have become an option to sustain current and future energy demands. One promising and reliable alternative energy is the Fischer-Tropsch synthesis (FTS), which is a gas-to-liquid (GTL) technology that converts syngas from a low-value feedstock, for example, from coal, biomass, or natural gas, into a high-value liquid hydrocarbon. In addition, FTS is a highly exothermic catalytic reaction that requires careful thermal management …

Single-Stage, Venturi-Driven Desalination System, Brandon Proetto

Mechanical & Aerospace Engineering Theses & Dissertations

Water demand is increasing at a rapid pace due to population increase, industrial expansion, and agricultural development. The use of desalination technology to meet the high water demands has increased global online desalination capacity from 47 million m^3/d in 2007 to 92.5 million m^3/d as of June 2017 [49]. Membrane and thermal processes are the two mainstream desalination categories used worldwide for desalination plants. Reverse Osmosis (RO) is the most widely used membrane process and it has become the dominant technology for building desalination plants over recent decades. Thermal distillation, however, has become less and less competitive due to its …

Prerequisites For Public Acceptance Of Waste-To-Energy Plants: Evidence From Germany And Indonesia, Uwe Lahl, Barbara Zeschmar-Lahl

Makara Journal of Technology

Construction of waste incinerators often encounters resistance from the public. The minimum requirements for the ac- ceptance of these installations include modern air pollution control (APC) technology and safe disposal of residues. Confidence in the statements of government and government agencies as well as on those who support is an important point of acceptance. Independent scientific bodies such as universities can help to make this happen. In the case of the installation of waste into energy (WtE), such scientific support can be the measurement of emissions and their evalua- tion. Many products that enter the waste stream contain heavy metals, …

Industrial Conveyors’ Taxonomy And Its Applications, A. Hoshimov, A. Rustamov, J. Rozzokov

Acta of Turin Polytechnic University in Tashkent

In any manufacturing processes includes a material handling equipment that can transport raw material or semi-finished products from the one workstation to another. Material handling equipment are designed based on the type of manufacturing product or the process. Therefore, engineers can easily make decision anaylsis while the selection of the most preferred type of industrial conveyors among others. This paper focuses on the industrial conveyors that classifies all available conveyor types. In this work is defined a review that covers most of the currently available literatures and conveyors types that describes industrial conveyors, types, characteristics and applications. A taxonomy is …

An Anisotropic Constitutive Model For Nuclear Grade Graphite, James Christopher

ETD Archive

Graphite material is used extensively in nuclear reactors however the material has a limited strain range for elastic behavior. This provides the motivation to derive a constitutive model that captures the inelastic deformations exhibited by this material. This dissertation first presents details of an isotropic constitutive model derived using continuum principles of engineering mechanics that accounts for different inelastic behavior in tension and compression. An inelastic dissipation function was developed using an integrity basis proposed by Green and Mkrtichian (1977) for the isotropic version of the model. This isotropic model was then extended to capture anisotropic stress-strain behavior using directional …