Mechanical Engineering Commons^™

Cryogenic System Development For Lox/ Hydrocarbon Propulsion Research, Francisco Pineda

Open Access Theses & Dissertations

A propulsion research facility is being developed at the Center for Space Exploration Technology Research (cSETR) at the University of Texas at El Paso (UTEP). These facilities were developed in order to meet new research demand for Liquid Oxygen (LOX)/Liquid methane (LCH4) experiments. The main goal of this system is to produce in-house liquid methane and supply propellants to their respective test set up in a cryogenic state. The work presented describes the design, development, and operation of a liquid methane condensation system and a cryogenic delivery feed system. The condensation system design will allow for a production of methane …

Oxidation Of Borides And Carbides With Y2o3 And Ta Additions, Salvador Manuel Rodriguez

Open Access Theses & Dissertations

The study presented here describes an investigation of an oxidation scale of a fully-sintered Y2O3-ZrB2-TiC composite exposed in air at 1173K. Upon oxidation of the boride/carbide, a ZrO2-TiO2 was expected to form similar to the ZrO2-SiO2 dual scale of an oxidized ZrB2-SiC. The 47wt% Y2O3-38wt%ZrB2-16wt%TiC composite formed a dual scale consisting primarily of an Y2O3-ZrO2-TiC inner scale with an outer scale of ZrO2-TiO2-Y2O3.

The samples oxidized with a parabolic layer growth allowing the calculation of the effective diffusion coefficient indicating that the oxidation was controlled by oxygen ingress through primarily the ZrO2-Y2O3 phase. The oxygen potential between the inner layer …

Investigation On A Gas-Solid Fluidized Bed Hydrodynamics Using A Non-Intrusive Technology To Visualize Flow Field, Md Rashedul Hasan Sarker

Open Access Theses & Dissertations

The biggest challenge for 21st century is to fulfill global energy demand and at the same time reduce detrimental impact on environment. Gasification technology can meet the requirement and also reduce emission without compromising its performance. In coal gasification, instead of burning coal completely a partial combustion takes place with presence of steam and limited amount of oxygen. In this controlled environment a chemical reaction takes place and produces a mixture of clean synthetic gas. Gas-solid fluidized bed is one type of gasification technology. During gasification mixing behavior of solid (coal) and gas and their flow pattern very complicated to …

Investigation Of A Water Desalination Method Via A Humidification-Dehumidification Process Using Hvac Technology, Juan A. Cornejo

Open Access Theses & Dissertations

Potable water is becoming a scarce resource in many arid regions of the world. An experimental unit was designed and constructed to examine and characterize the production capabilities of a humidification-dehumidification (HDH) desalination process. An HDH cycle offers a viable, technologically light, alternative for producing fresh water from brackish water because the low relative humidity air is infused with water vapor through evaporation by means of conventional heating, ventilation and air conditioning (HVAC) components. The evaporation process effectively separates salts and suspended solids from the brackish feed-water. Desalinated water is subsequently recovered by extracting the water vapor from the moist …

Impact Testing Of Zirconium Diboride, Mark David Flores

Open Access Theses & Dissertations

Refractory ceramic materials such as zirconium diborides (ZrB2) have been excellent candidate materials for application in turbine blades, leading edge surfaces of high mach aircraft and high temperature applications. This is due to their good strength at high temperatures (T>1800°C). But questions on their ultimate durability at such temperatures remains an issue, especially with respect to foreign object impact damage as well as oxidation. Little characterization of such materials of the impact durability of such materials at very high temperatures has been performed - In this talk an experimental approach for the impact testing of ceramic materials at elevated …

Numerical Analysis Of Single Tank Thermocline Thermal Storage System For Concentrated Solar Power Plant, Samia Afrin

Open Access Theses & Dissertations

The overall efficiency of a Concentrating Solar Power (CSP) plant depends on the effectiveness of Thermal Energy Storage (TES) system. A Single tank TES system has potential to provide effective solution. In a single tank TES system, a thermocline region, which produces the temperature gradient between hot and cold storage fluid by density difference, is used. Preservation of this thermocline region in the tank during charging and discharging cycles depends on the uniformity of the velocity profile at any horizontal plane. One of the major challenges for the single tank thermocline is actually maintaining the thermocline region in the tank, …

Instrumentation, Control And Torch Ignition Systems Development For Lox/Methane Propulsion Research, Jesus Betancourt-Roque

Open Access Theses & Dissertations

A liquid propulsion research facility has been developed at the Center for Space Exploration Technology Research at The University of Texas at El Paso. This facility has capabilities for producing up to 25 liters of Liquid Methane, feeding LOX/Methane propellants to 100 N class thrusters and conducting automated steady state and pulsing combustion experiments. This work describes the design, development and testing process of the Data Acquisition and Remote Control System developed to integrate an Altitude Simulation System, a Cryogenic Delivery System, and multiple rocket combustors and thrusters. A Torch Ignition System development is detailed as well as the evaluation …

Dynamic Characterization Of Vocal Fold Virbrations, Zhenyi Wei

LSU Doctoral Dissertations

An emerging trend among voice specialists is the use of quantitative protocols for the diagnosis and treatment of voice disorders. Vocal fold vibrations are directly related to voice quality. This research is devoted to providing an objective means of characterizing these vibrations. Our goal is to develop a dynamic model of vocal fold vibration, and map the parameter space of the model to a class of voice disorders; thus, furthering the assessment and diagnosis of voice disorder in clinical settings.

To this end, this dissertation introduces a new seven-mass biomechanical model for the vibration of vocal folds. The model is …

Ranging Of Aircraft Using Wide-Baseline Stereopsis, Kevin Todd Rigby

Doctoral Dissertations and Master's Theses

The purpose of this research was to investigate the efficacy of wide-baseline stereopsis as a method of ranging aircraft, specifically as a possible sense-and-avoid solution in Unmanned Aerial Systems. Two studies were performed: the first was an experimental pilot study to examine the ability of humans to range in-flight aircraft and the second a wide-baseline study of stereopsis to range in-flight aircraft using a baseline 14.32 meters and two 640 x 480 pixel charge coupled device camera. An experimental research design was used in both studies. Humans in the pilot study ranged aircraft with a mean absolute error of 50.34%. …

Computational Analysis Of Hybrid Norwood Circulation With Distal Aortic Arch Obstruction And Reverse Blalock-Taussig Shunt, Andres Ceballos, I. Ricardo Argueta-Morales, Eduardo Divo, Ruben Osorio, Christopher A. Caldarone, Alain J. Kassab, William M. Decampli

Mechanical Engineering - Daytona Beach

BACKGROUND: The hemodynamics characteristics of the hybrid Norwood (HN) procedure differ from those of the conventional Norwood and are not fully understood. We present a multi-scale model of HN circulation to understand local hemodynamics and effects of aortic arch stenosis and a reverse Blalock-Taussig shunt (RBTS) on coronary and carotid perfusion. METHODS: Four 3-dimensional models of four HN anatomic variants were developed, with and without 90% distal preductal arch stenosis and with and without a 4-mm RBTS. A lumped parameter model of the circulation was coupled to a local 3-dimensional computational fluid dynamics model. Outputs from the lumped parameter model …

High Tech High Touch: Lessons Learned From Project Haiti 2011, Yan Tang, Marc Compere, Yung Lun Wong, Jared Anthony Coleman, Matthew Charles Selkirk

Publications

In this paper, we will share our experiences and lessons learned from a design project for providing clean water to a Haitian orphanage (Project Haiti 2011). Supported by funds from a renewable energy company and the university president’s office, five engineering students and two faculty members from Embry-Riddle Aeronautical University successfully designed and installed a solar powered water purification system for an orphanage located in Chambellan, Haiti. This paper discusses the unique educational experiences gained from unusual design constraints, such as ambiguity of existing facilities due to limited communication, logistics of international construction at a remote village location, and cross-cultural …

Multi-Disciplinary Hands-On Desktop Learning Modules And Modern Pedagogies, Bernard J. Van Wie, David B. Thiessen, Marc Compere, Ximena Toro, Jennifer C. Adam, Et Al.

Publications

Our team’s research focuses on fundamental problems in undergraduate education in terms of how to expand use of well researched, yet still “new”, teaching pedagogies of ‘sensing’ or ‘hands-on’, ‘active’ and ‘problem-based learning’ within engineering courses. It is now widely accepted that traditional lectures ARE NOT best for students – yet that is what the community almost universally does.

To address this issue we are developing new Desktop Learning Modules (DLMs) that contain miniaturized processes with a uniquely expandable electronic system to contend with known sensor systems/removable cartridges, as well as, unknown expansions to the project. We have shown that …

Direct Verification Of The Locking Of Liquid Locking Compounds In Threaded Fasteners, Ryan Hunter

USF Tampa Graduate Theses and Dissertations

The motivation of this research is to explore the viability of a method to directly verify whether or not an anaerobic adhesive within a threaded fastener assembly has cured sufficiently to provide secondary locking. Direct verification was implemented via the application of a test torque in the loosening direction of a fastener assembly with Loctite (given a 24 hour cure time). A three phase test plan was developed with the intent of identifying and utilizing this verification torque value which is unique to a given fastener assembly.

It was proved that the direct verification method, as outlined in the test …

Chemical Mechanical Planarization Of Electronic Materials, Fnu Atiquzzaman

USF Tampa Graduate Theses and Dissertations

In the modern semiconductor manufacturing processes, chemical mechanical planarization (CMP) has attained important processing step because of its ability to provide global planarization. CMP is the planarization technique which is used for the removal of excess material, as left over from the previous processing steps. In addition, CMP offers a uniform surface that is essential for subsequent processing steps, especially for the high resolution photolithography processes. In simpler notation, CMP is a process where a chemical reaction enhances in obtaining a planar surface through removal of the mechanical materials from a wafer.

In this study, CMP performance of three electronic …

Design Of Contact Line Friction Measurement Machine Apparatus, Seyed Kamran Najafi

USF Tampa Graduate Theses and Dissertations

The purpose of this project is to design and manufacture a high precision machine to directly measure the surface force of fluids. Knowing how to move droplets easier with less resistance can increase the potential of a wide range of applications and improve the performance of things such as self-assembly applications. This machine has the ability to measure forces of up to 100 N with a MEMS based sensor. The motion system on this machine moves a substrate underneath of a droplet for 100 mm and applies dragging force to the sensor. It moves with a controlled speed with high …

Fluidic Assembly At The Microscale: Progress And Prospects, Nathan B. Crane, Onursal Onen, Jose Carballo, Qi Ni, Rasim Guldiken

Faculty Publications

Assembly permits the integration of different materials and manufacturing processes to increase system functionality. It is an essential step in the fabrication of useful systems across size scales from buildings to molecules. However, at the microscale, traditional “grasp and release” assembly methods and chemically inspired self-assembly processes are less effective due to many scaling effects. Many methods have been developed for improving microscale assembly. Often these methods include fluidic forces or the use a fluidic medium in order to enhance their performance. This paper reviews basic assembly theory and modeling methods. Three basic assembly strategies (tool-directed, process-directed, and part-directed) are …

Factors Impacting Technology Transfer: The Maquiladora Industry In Yucatan, Mexico, Ana Maria Canto, Carlos Blanco, Pilar Pazos

Engineering Management & Systems Engineering Faculty Publications

Technology transfer and knowledge transfer are the building blocks for innovation, efficiency and increased competitiveness. The topic of technology transfer in the context of multinational companies has been the focus of technology management researchers for well over two decades. Developing countries housing twin plans have been exposed to technology transfer from very diverse countries with different approaches to the technology transfer process and different levels of success. This cultural and national diversity adds an additional level of complexity to the technology transfer domain that has been largely unexplored. This paper will explore critical factors that had an impact in successful …

Design Of A Vortex Induced Vibration Based Marine Hydro-Kinetic Energy System, Varun Michael Lobo

Masters Theses

"Hydrokinetic energy harvesting based on vortex induced vibration (VIV) of a bluff body is discussed. VIV is defined as the vibration incurred on a bluff body due to an external fluid flowing over it. These vibrations are the results of boundary layer separation from the surface of the body. An optimized VIV generator has been developed, that utilizes a non-contact type linear magnetic device for generation of energy. The cylinder was chosen such that at the mass ratio (m*) was always lower than the critical mass (m*_critical= 0.52). The studies were based on two complementary …

Applied Energy Systems: Hydrostatic Fluid Power Transmission And Flow In Pipes, Jim Mcgovern

Book/Book Chapters

This is an intentionally compact textbook or set of notes for a module addressing basic Fluid Mechanics for incompressible fluids within the context of Applied Energy Systems. Rather than attempting to cover Fluid Mechanics in a very broad and general way, two practical areas are selected in the use of fluids: hydrostatic power transmission systems and the flow of fluids through pipes and fittings. This allows the two areas to be presented in some detail, but also allows them to be sample application areas that would enable learners to put the principles of fluid mechanics into context, while developing their …

A Simulation Analysis Of Photovoltaic Ac Module Integrated Converters In Parallel, Under Controlled Edge Shading Conditions, Lynette O'Callaghan, Mick Mckeever, Brian Norton

Conference Papers

A DC and AC power simulation comparison of: a Photovoltaic (PV) array with a modular, parallel, AC converter configuration; and a series, string configuration with a central AC converter, is presented. The systems are simulated using a comprehensive range of edge shading scenarios and irradiance conditions. Power control and transformation circuitry must be designed for shade and module mismatch tolerance to prevent over-proportional power to shade losses, as average losses from Building Integrated PV (BIPV) systems are approximately 20 to 25%, due to shade, mismatch, differences in orientation and inclination, and temperature effects. 59.4% of the simulations showed gains in …