Electro-Mechanical Systems Commons^™

Design And Implementation Of A Small Electric Motor Dynamometer For Mechanical Engineering Undergraduate Laboratory, Aaron Farley

Graduate Theses and Dissertations

This thesis set out to design and implement a new experiment for use in the second lab of the laboratory curriculum in the Mechanical Engineering Department at the University of Arkansas in Fayetteville, AR. The second of three labs typically consists of data acquisition and the real world measurements of concepts learned in the classes at the freshman and sophomore level. This small electric motor dynamometer was designed to be a table top lab setup allowing students to familiarize themselves with forces, torques, angular velocity and the sensors used to measure those quantities, i.e. load cells and optical encoders. The …

Sole Power: Pedal Phone Charger Final Report, Nicole Hensley, Anthony Ruh, Krista Schmidt, Joseph Garcia

Mechanical Engineering

The device design was conceived to meet the energy needs of rural populations in India. These communities have cell phones but lack access to reliable grid power, especially during monsoon season. The charger is designed to be affordable, durable, and easily repairable for each owner family. It uses off-the-shelf components and is intended to be replicated by backyard manufacturing startups in developing countries.

Its purpose is to efficiently transfer human foot motion via a treadle, four-bar-linkage, and sprocket-chain step-up to drive a rotor & stator generator from a common gas scooter. The single-phase alternating current from the generator is passed …

Upgrading Unlv's Astm E477 Test Facility To Meet The Current Standards Of Astm E477, Ronn Fojas

UNLV Theses, Dissertations, Professional Papers, and Capstones

A by-product of Heating, Ventilation, and Air-conditioning (HVAC) systems is noise that is produced by fans, compressors, and other related equipments and the noises from the turbulence that is created by moving air. Sometimes, it is impractical to modify the sources of the noise, which requires designers to modify the path of the noise, the duct system. These modifications might include installing an in-duct silencer or acoustical lining on the inside walls of the ducts. The testing and the precise quantification of the performance of these silencers and duct linings are necessary for any designer to be able to make …

Numerical Modeling Of High Temperature Bayonet Heat Exchanger And Decomposer For Decomposition Of Sulfur Trioxide, Vijaisri Nagarajan, Yitung Chen, Tzu-Chen Hung, Qiuwang Wang, Valery Ponyavin

College of Engineering: Graduate Celebration Programs

Motivation

• Hydrogen is an attractive energy carrier in the future energy technology.

• Hydrogen is produced from splitting of water through various process namely electrolysis, photo-electrolysis, photo-biological production and thermochemical water-splitting.

• The aim of this study is to numerically investigate fluid flow, heat transfer and chemical reaction in bayonet high temperature heat exchanger and decomposer.

• Parametric studies are performed to achieve maximum decomposition with less pressure drop.

A Ceramic-Anode Supported Low Temperature Solid Oxide Fuel Cell, Hanping Ding, Junjie Ge, Xingjian Xue

Faculty Publications

We report the fabrication and evaluation of a ceramic-anode supported button cell LSCM-SDC/SDC/PBSC (thickness 400 μm/20 μm/20 μm). The anode/electrolyte assembly LSCM-SDC/SDC was co-fired at low temperature of 1250°C, where a slight amount of CuO was mixed with LSCM. The CuO (20.3 wt%) were impregnated into the porous substrate to enhance current collecting effect. The cell exhibited power density of 596 mWcm−2 and 381 mWcm−2 at 700°C with wet hydrogen and methane as the fuel respectively, where the silver paste was used as current collectors, the highest performance up to date for the cells with metal oxide anodes at this …

Pedaling And Braking Forces And Their Effect On Suspension Performance, Kathleen Kramer, Nik Goodell, Cesar Giron

Mechanical Engineering

The goal of this project is to produce a quantifiable relationship between pedaling and braking forces and suspension behavior. The test results will serve as a benchmark, against which other suspension designs can be compared in an objective, numerical manner. This report details the work completed towards determining this relationship and is primarily focused on design development of the data acquisition system and analysis of braking forces, pedaling forces and suspension response. A 2011 Specialized Stumpjumper FSR Expert Evo was used as the development platform. The system will be used to measure various rear suspension designs for comparison.

A New Approach For The Preparation Of Variable Valence Rare Earth Alloys From Nano Rare Earth Oxides At A Low Temperature In Molten Salt, Milin Zhang, Yongde Yan, Wei Han, Xing Li, Zhiyao Hou, Yang Tian, Ke Ye, Lihong Bao, Xiaodong Li, Zhijian Zhang

Faculty Publications

The solubility of RE₂O₃ (RE = Eu, Sm, and Yb) with variable valence in molten salts is extremely low. It is impossible to directly obtain variable valence metals or alloys from RE₂O₃ using electrolysis in molten salts. We describe a new approach for the preparation of variable valence rare earth alloys from nano rare earth oxide. The excellent dispersion of nano–Eu₂O₃ in LiCl–KCl melts was clearly observed using a luminescent feature of Eu³⁺ as a probe. The ratio of solubility of nano-Sm₂O₃/common Sm₂O_{3 …}

Electrokinetic Flow In Polyelectrolyte–Modified Nanopores, L. H. Yeh, M. Zhang, Shizhi Qian, J. P. Hsu, S. W. Joo

Mechanical & Aerospace Engineering Faculty Publications

No abstract provided.

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 …

Development Of A Robotic Platform For Upper Limb Rehabilitation, Stephen Curran, Nigel Kent, David Kennedy, James Conlon

Conference Papers

The aim of this project is to develop a rehabilitation robot intended for use in a non-specialised or domestic setting. Robots have been shown to have a positive effect on limb rehabilitation and developing rehabilitation robots for use outside of specialist rehabilitation centres could be beneficial in terms of access to, intensity and cost of treatment. The device is intended for the rehabilitation of the shoulder/elbow region of the upper limbs. The design requirements for such a device mean that it must be low cost, portable, robust and have a detailed focus on safety. Other areas of interest pertaining to …

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 …

A Material System For Reliable Low Voltage Anodic Electrowetting, Mehdi Khodayari, Jose Carballo, Nathan B. Crane

Faculty Publications

Electrowetting on dielectric is demonstrated with a thin spin-coated fluoropolymer over an aluminum electrode. Previous efforts to use thin spin-coated dielectric layers for electrowetting have shown limited success due to defects in the layers. However, when used with a citric acid electrolyte and anodic voltages, repeatable droplet actuation is achieved for 5000 cycles with an actuation of just 10 V. This offers the potential for low voltage electrowetting systems that can be manufactured with a simple low-cost process.

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 …

Robotic Turret, Daniel Romero, Matthew (Matt) Martelle, Scott Mullens, Rachel Diamant

Mechanical Engineering

No abstract provided.

Quantification Of Stochastic Uncertainty Propagation For Monte Carlo Depletion Methods In Reactor Analysis, Quentin Thomas Newell

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Monte Carlo method provides powerful geometric modeling capabilities for large problem domains in 3-D; therefore, the Monte Carlo method is becoming popular for 3-D fuel depletion analyses to compute quantities of interest in spent nuclear fuel including isotopic compositions. The Monte Carlo approach has not been fully embraced due to unresolved issues concerning the effect of Monte Carlo uncertainties on the predicted results.

Use of the Monte Carlo method to solve the neutron transport equation introduces stochastic uncertainty in the computed fluxes. These fluxes are used to collapse cross sections, estimate power distributions, and deplete the fuel within depletion …

Linear Electromagnetic Energy Scavenging Device Designed In Low Temperature Co-Fired Ceramics, Hope A. Bateman

Boise State University Theses and Dissertations

For a soldier deployed in a remote location on the earth or a recreational hiker in the wilderness or a wild land firefighter battling a destructive wildfire, access to a power source is problematic. Local and regional communication systems, navigation, lights, imaging: all of these require a power source. For short time periods, batteries may be sufficient but with extended time periods the weight of the batteries and cost of replacement becomes a problem. Energy scavenging devices could fill this need and be used as a secondary power source when solar or batteries are not available.

A linear electromagnetic generator …

Floating Tube Heat Exchangers, Patrick Harris, Christina Gedeon, Leonel Medrano, George Milam

Mechanical Engineering

With the slowly diminishing supply of fossil fuels across the world and the heightened risk of carbon dioxide pollution leading to global warming, a shift towards renewable energy is gaining momentum. Recent advances in wind and solar power technology have increased the power density of alternative sources while decreasing the cost per kilowatt-hour, but the technology has not become advanced enough yet for large scale deployment. Combined Power Cooperative has developed a revolutionary design for a concentrated solar power plant that utilizes Fresnel reflectors and a large body of water in which to install them. In addition to being low-cost, …

Vibration-Based Health Monitoring Of Multiple-Stage Gear Train And Differential Planetary Transmission Involving Teeth Damage And Backlash Nonlinearity, Andrew Patrick Sommer

Master's Theses

The objective of this thesis is to develop vibration-based fault detection strategies for on-line condition monitoring of gear transmission systems. The study divides the thesis into three sections. First of all, the local stresses created by a root fatigue crack on a pinion spur gear are analyzed using a quasi-static finite element model and non-linear contact mechanics simulation. Backlash between gear teeth which is essential to provide better lubrication on tooth surfaces and to eliminate interference is included as a defect and a necessary part of transmission design. The second section is dedicated to fixed axis power trains. Torsional vibration …

Experimental And Numerical Investigations Of Tubular-Shaped Direct Methanol Fuel Cells (Dmfcs), Travis R. Ward

Master's Theses

This study focuses on both the numerical and experimental investigations of the novel, passively operated, tubular-shaped, Direct Methanol Fuel Cell (DMFC) as an alternative geometry to the traditional planar-shaped fuel cell. The benefit of the tubular geometry compared to the planar geometry is the higher instantaneous volumetric power density provided by the larger active area, which could be beneficial in applications that require a high instantaneous power while occupying a small volume. First, a two-dimensional, two-phase, non-isothermal model was developed to investigate the steady-state performance and design characteristics of a tubular-shaped, passive DMFC. It was found that a higher ambient …

Understanding The Role Of A Bio-Inspired Surface Modification For Delayed Icing, Clayton Schenk

Graduate Theses and Dissertations

Atmospheric icing event is problematic for outdoor structures because it can damage, slow, impede, and danger general routine. For a wind turbine blade, it can damage, disrupt movement, and cause potentially dangerous ice throw. Anti-icing based on a surface texture is advantageous due to the low cost of maintenance and there is no additional requirement of energy output for preventing the icing problem. This work is based on the biomimicry of the superhydrophobic nature of the lotus leaf, whereas the limited wettability supports the water to flow freely from the surface structure. The phenomenon is based on a morphology and …