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Measurement And Prediction Of The Onset Of Intermittent Dryout During Blowdown Transients For Upward Annular Flow, Bradley A. Statham 2014 McMaster University

Measurement And Prediction Of The Onset Of Intermittent Dryout During Blowdown Transients For Upward Annular Flow, Bradley A. Statham

Open Access Dissertations and Theses

The effect of pressure transients on the onset of intermittent dryout in upward annular flow was experimentally investigated in order to resolve the conflict between the observations drawn from two major data sets in the literature. A delay in time to the onset of dryout at the test section exit relative to the time predicted based on steady-state data was observed in the R-12 experiments of Celata et al (1988; 1991). Steady-state prediction methods were sufficient to predict the upstream progression of a pre-existing dryout front in the water experiments of Lyons and Swinnerton (1983). Steady state and pressure transient ...


Educational Programmes For Spatial Information Sciences In The Dublin Institute Of Technology, William Prendergast, Eamonn Donnelly, Audrey A. Martin, Avril Behan 2014 Dublin Institute of Technology

Educational Programmes For Spatial Information Sciences In The Dublin Institute Of Technology, William Prendergast, Eamonn Donnelly, Audrey A. Martin, Avril Behan

Conference Papers

The ever increasing spatial information needs of society, the rapid development of new surveying technologies, and the global demand for appropriately qualified surveyors, have triggered a radical re-evaluation of geomatics education worldwide. Significant enhancements have been made to the educational programmes in the spatial information science discipline in the Dublin Institute of Technology’s (DIT) during the last decade including the provision of a BSc in Geomatics and various masters’ programmes to cater for the increasingly specialised needs of the Geographic Information sector in Ireland.


Implications Of Rough Dielectric Surfaces On Charging-Adjusted Actuation Of Rf-Mems, Sambit Palit, Xin Xu, Arvind Raman, Muhammad Ashraful Alam 2014 Purdue University

Implications Of Rough Dielectric Surfaces On Charging-Adjusted Actuation Of Rf-Mems, Sambit Palit, Xin Xu, Arvind Raman, Muhammad Ashraful Alam

Birck and NCN Publications

Actuation voltage shifts due to dielectric charging is a leading reliability concern in Radio-Frequency Micro-Electro-Mechanical Systems (RF-MEMS) capacitive switches. The inability to correlate dielectric surface roughness to charge accumulation makes predictive design difficult. We apply a sophisticated dielectric charging model on representative surfaces based on Atomic Force Microscopy (AFM) data, and show that there are significant, but predictable actuation voltage shifts due to surface roughness. The results suggest that surface roughness should be considered for accurate lifetime predictions, and simple metal-insulator-metal (MIM) capacitors may serve as a useful test structure for this phenomenon.


Msu Xtreme: Minnesota State University, Mankato's Entry Into The "Clean Snowmobile Challenge 2001", Scott Betcher, Allen Caldwell, Nathan Lindeman, Brian Mandelkow, Dave Maniak, Randy Rohlf, James Skuya, Dennis Swanson, Aaron Wolff, Mark Brandl, Dan Dobesh, Ryan Erickson, Jeff Gillen, Jan Smith, Jason Wilkie 2014 Minnesota State University, Mankato

Msu Xtreme: Minnesota State University, Mankato's Entry Into The "Clean Snowmobile Challenge 2001", Scott Betcher, Allen Caldwell, Nathan Lindeman, Brian Mandelkow, Dave Maniak, Randy Rohlf, James Skuya, Dennis Swanson, Aaron Wolff, Mark Brandl, Dan Dobesh, Ryan Erickson, Jeff Gillen, Jan Smith, Jason Wilkie

Journal of Undergraduate Research at Minnesota State University, Mankato

Minnesota State University, Mankato’s Automotive Engineering Technology program formed a team to enter the Clean Snowmobile Challenge 2001. Selections for the organization’s machine included a 2001 Polaris Edge Chassis specially outfitted with a 2000 500 cc two-stroke Polaris engine. Modifications to the snowmobile were made specifically for Clean Snowmobile Challenge 2001 events. Acceleration, emissions, cold start, noise, fuel economy/range, handling/drivability, hill climb, and static display made up the list of events featured in the competition. MSU Xtreme has modified the snowmobile in every area with special emphasis on emissions and handling. Testing and analysis of the ...


Formula-Sae Wireless Data Logger, Eric Holland 2014 Minnesota State University, Mankato

Formula-Sae Wireless Data Logger, Eric Holland

Journal of Undergraduate Research at Minnesota State University, Mankato

The Formula-SAE (Society of Automotive Engineers) race car requires an onboard data logger to obtain and record the performance information received from the Fuel Injection Controller. This data is needed for analyzing the engine performance of the race car. It is advantageous to have this unit transmit the data via a wireless link to a handheld monitoring tool. Having user interface, like a LCD screen and a keypad, would make the monitoring tool easy to use. Also making the monitoring tool communicate with a PC would offer the beneficial features of saving and printing data. By having the PC connectivity ...


Applied Energy Systems - Rudimentary Thermodynamics, Jim McGovern 2014 Dublin Institute of Technology

Applied Energy Systems - Rudimentary Thermodynamics, Jim Mcgovern

Book/Book Chapters

This is a compact textbook for a module addressing rudimentary thermodynamics within the context of applied energy systems. It is at an introductory level for engineers or technologists. The book does not attempt to cover the principles of thermodynamics comprehensively. Rather, it provides a practical but theoretically sound foundation, linked to some key areas. Energy, heat and work are all introduced, as are units and dimensions. Ideal gases and properties of liquids and vapours are treated. Non-flow and steady flow processes are described. Simple theory is provided for pumps and for the reciprocating compressor. Rudimentary steam and refrigeration or heat ...


Surface Modification Of Aluminum Alloys By Plasma Electrolytic Oxidation, Vahid Dehnavi 2014 Western University

Surface Modification Of Aluminum Alloys By Plasma Electrolytic Oxidation, Vahid Dehnavi

University of Western Ontario - Electronic Thesis and Dissertation Repository

Plasma Electrolytic Oxidation (PEO) is a surface treatment for the production of ceramic oxide coatings with great properties, such as high wear and corrosion resistance, on metal substrates, particularly aluminum and magnesium alloys. Formation of PEO coatings involves complex processes and mechanisms that are difficult to study. Currently, the PEO process is in a transition phase from research to commercial application, with a primary focus on the corrosion and wear protection of light alloys, and has recently generated interest as a promising surface treatment for biomedical applications.

To justify the industrial application of PEO, a more systematic and in-depth study ...


Uncertainty Quantification For A Class Of Mems-Based Vibratory Angular Rate Sensors, Nujhat Abedin 2014 Western University

Uncertainty Quantification For A Class Of Mems-Based Vibratory Angular Rate Sensors, Nujhat Abedin

University of Western Ontario - Electronic Thesis and Dissertation Repository

Numerical schemes that are suitable for predicting response statistics of mass-spring and ring gyroscopes are developed when this class of vibratory gyroscopes are subjected to certain system parameters as well as environment uncertainties. The emphasis is placed on the steady-state part of the response since it is more critical to the operation of a gyroscope. A peak-picking approach which simulates the demodulation process which is used in practice is employed first before applying the Monte Carlo simulation method to predict the response statistics. A number of simulation trials to predict response statistics have been performed for mass-spring and ring-type gyroscopes ...


Numerical Analysis Of Two Phase Flow And Heat Transfer In Condensers, Pooya Mirzabeygi 2014 Western University

Numerical Analysis Of Two Phase Flow And Heat Transfer In Condensers, Pooya Mirzabeygi

University of Western Ontario - Electronic Thesis and Dissertation Repository

Steam surface condensers are commonly used in the power generation industry and their performance significantly affects the efficiency of the power plant. Therefore, it is vital to acquire a better understanding of the complex phenomena occurring inside condensers. A general three-dimensional numerical model is developed in this study to simulate the two-phase flow and heat transfer inside full-scale industrial condensers with irregular tube bundle shapes. The Eulerian-Eulerian two-phase model is selected to simulate gas and liquid flows and the interaction between them. A porous media approach is adopted to model the presence of large number of tubes in the condenser ...


Three Dimensional Transient Asymmetric Flowfields In Physical Vapor Transport, Joseph Dobmeier 2014 Minnesota State University, Mankato

Three Dimensional Transient Asymmetric Flowfields In Physical Vapor Transport, Joseph Dobmeier

Journal of Undergraduate Research at Minnesota State University, Mankato

Physical Vapor Transport is a manufacturing process used to produce single crystals of semiconductor materials such as mercurous chloride (Hg2Cl2). In the past this time-varying process has been studied with numerical simulation by considering three dimensional flow using an axi-symmetric two dimensional model or by restricting the simulation to asymmetric two dimensional flow and dropping the assumption of axi-symmetry from the model. It is generally agreed that neither of these methods accurately represent the true behavior of the process. The purpose of this research was to extend the asymmetric two dimensional model to three dimensions thereby obtaining a solution which ...


Shape Optimization Of Airfoils Without And With Ground Effect Using A Multi-Objective Genetic Algorithm, Yilei He 2014 Washington University in St. Louis

Shape Optimization Of Airfoils Without And With Ground Effect Using A Multi-Objective Genetic Algorithm, Yilei He

Engineering and Applied Science Theses & Dissertations

The focus of this thesis is on shape optimization using a genetic algorithm. A multi-objective genetic algorithm (MOGA) is employed to optimize the shape of an airfoil to improve its lift and drag characteristics, in particular to achieve two objectives simultaneously that is to increase its lift as well as its lift to drag ratio. The commercially available software FLUENT is employed to calculate the flow field on an adaptive structured mesh, which is generated by the commercial mesh generating software ICEM. The flow field is calculated using the Reynolds-Averaged Navier-Stokes (RANS) equations in conjunction with a two equation k-ω ...


Fluid Powered Miniature In-Vivo Robots For Minimally Invasive Surgery (Mis), Abolfazl Pourghodrat 2014 University of Nebraska - Lincoln

Fluid Powered Miniature In-Vivo Robots For Minimally Invasive Surgery (Mis), Abolfazl Pourghodrat

Mechanical (and Materials) Engineering -- Dissertations, Theses, and Student Research

Minimizing the invasiveness of surgery is believed to improve patient outcomes. Bleeding, infection, and pain are major concerns in surgery afflicting patients for decades. Minimally invasive techniques have come into play to reduce these concerns and smooth the evolution of abdominal surgery to a scarless process where nearly all surgeries can be performed without a skin incision. Technology continually advances the frontier of development of novel surgical devices to implement less invasive surgical techniques.

Fusion of robotics and Minimally Invasive Surgery (MIS) has created new opportunities to develop diagnostic and therapeutic tools. Surgical robotics is advancing from externally actuated systems ...


Foss Big Data Storage Solution, nurdeen salami 2014 California Polytechnic State University

Foss Big Data Storage Solution, Nurdeen Salami

STEM Teacher and Researcher (STAR) Program Posters

NASA projects require a reliable approach to store large volumes of data. Accordingly, it is crucial to adopt a lightweight, reliable, and scalable database. Current NASA databases bear costly license fees with undesirable speed and flexibility. The purpose of utilizing the AERO Institute as an IT test bed, or “Sandbox,” is to design, build, test, and implement software solutions prior to transfer to NASA projects. Cassandra coupled with the Astyanax API is a viable solution for storing big data. Store a minimum of 2GB of C-FOSS data in multiple file formats (.csv, .log, .xml, and .jpg). Use benchmark tests to ...


Space Race: Capturing An Orbiting Sample And A Nation’S Imagination, Stephanie La Liberte, Andrew Chavarin, Shubham Gogna, C. Daniel Thomas, Vy Phung, Gabriel Udomkesmalee 2014 California Polytechnic State University

Space Race: Capturing An Orbiting Sample And A Nation’S Imagination, Stephanie La Liberte, Andrew Chavarin, Shubham Gogna, C. Daniel Thomas, Vy Phung, Gabriel Udomkesmalee

STEM Teacher and Researcher (STAR) Program Posters

A proposed architecture for future planetary sample return missions would consist of capturing on-orbit a sample container (collected from the surface of a planetary body and launched into space) and transferring the sample container into an earth return/reentry capsule. A challenge to this proposed architecture is integrating space applicable sensor technologies with sufficient capturing devices. While useful technologies on Earth, Earth-related rendezvous/capture technologies, such as magnetic field sensors, sound-based sensors, and Earth orbit-based radios like GPS, are not applicable to space. Inspired by the in-orbit sample capture challenge, NASA JPL has designed the Space Rendezvous And Capture Experiment ...


Carbon Nanotube Powered Regenerative Braking System, Corbin Ross Martin 2014 Northeastern University

Carbon Nanotube Powered Regenerative Braking System, Corbin Ross Martin

Mechanical Engineering Master's Theses

Regenerative braking systems capture kinetic energy and store it for later use, for example as electrochemical energy in a battery or as kinetic energy in a flywheel. There are currently no commercially available regenerative braking systems that convert kinetic energy into elastic strain energy for storage. Although elastically-deformed springs can permit rapid energy storage during braking and rapid energy release during acceleration, springs made of conventional materials do not have high enough energy densities for practical regenerative braking systems in vehicles. In contrast, carbon nanotubes have incredibly high tensile strength and maximum strain, so that they offer the potential for ...


Influence Of Viscosity Gradient On Bubble Formation At A Submerged Orifice, Leily Majidi 2014 Northeastern University

Influence Of Viscosity Gradient On Bubble Formation At A Submerged Orifice, Leily Majidi

Mechanical Engineering Master's Theses

The objective of the present work was to experimentally investigate bubble formation in different viscosities of Silicone oil. The purpose of these experiments was to try to understand how the shape of the bubbles, formed from a small lower orifice, is affected by aspects of viscosity. The two major directions of investigation involved bubble formation in (i) single and finite liquid layers of varying viscosity and (ii) multiple layers of varying viscosities, to create a viscosity gradient. The experiments were inspired by recent observations of Focused Ion Beam FIB movies of thermal sprayed obsidian splats, in which different elongated `frozen ...


Applied Strength Of Materials For Engineering Technology, Barry Dupen 2014 Indiana University – Purdue University Fort Wayne

Applied Strength Of Materials For Engineering Technology, Barry Dupen

Manufacturing and Construction Engineering Technology and Interior Design Faculty Publications

No abstract provided.


A Systematic Study Of The Process-Structure Relationship For Building Polymer Interphase Regions In Carbon Nanotube Composites, Yiying Zhang 2014 Northeastern University

A Systematic Study Of The Process-Structure Relationship For Building Polymer Interphase Regions In Carbon Nanotube Composites, Yiying Zhang

Mechanical Engineering Dissertations

As the world's demands for new high-performance materials continuously grow, reinforcing polymer materials with carbon nanotubes (CNT) to produce lightweight composites with high properties has been pursued since their discovery. However, to date composites with the anticipated superior properties have not been achieved yet. This is mainly due to the lack of fundamental understanding regarding processing these materials as well as manipulating the nano-scale assemblies, which would dictate the desired macroscopic performance.

This dissertation work focuses on understanding the development of interfacial zones in polymer/CNT composites, which is necessary for producing mechanically outstanding composite materials. Highly crystalline and ...


Large Eddy Simulation Of Turbulent Flow Past A Bluff Body Using Openfoam, David Joseph Hensel 2014 Northeastern University

Large Eddy Simulation Of Turbulent Flow Past A Bluff Body Using Openfoam, David Joseph Hensel

Mechanical Engineering Master's Theses

Numerical simulation of a turbulent bluff-body flow is conducted using large eddy simulation (LES). The open source CFD software package, OpenFOAM, is employed to solve the LES filtered transport equations governing the three-dimensional incompressible flow in the wake of the body. This work is motivated by the importance of bluff-body flows, for example, in flame stabilization in industrial combustors and burners, as well as in aerodynamics applications. The focus of the study is on the proper generation of turbulence at the inlet boundary. Standard boundary conditions available in OpenFOAM are not sufficient for providing an accurate turbulent inlet condition without ...


Design And Analysis Of New Flexible And Safe Forklifts, Yuru Shao 2014 Northeastern University

Design And Analysis Of New Flexible And Safe Forklifts, Yuru Shao

Mechanical Engineering Master's Theses

In today's life, there is a wide variety of forklifts, from the large heavy loading truck to the one that works among narrow aisles. Forklifts have become one of the basic transportation tools we use in our lives. With all the forklifts in existance, we find that there are some improvements that can be made to bring the forklift to a better performance.

Existing forklift design has its limitation in rotation and the structure has potential safety risk. Our new design has 180 degrees rotating forks attached to truck body on both ends. Also, it has a scissor lift ...


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