Mechanical Engineering Commons^™

Assessment Of Critical Technologies For Gas Turbine Engines Using Numerical Tools, Vinicius Pessoa Mapelli, Guillermo Paniagua, Jorge Sousa

The Summer Undergraduate Research Fellowship (SURF) Symposium

In 2014 gas turbine engine has reached a market value of 82.5 billion dollars, of which 59.5% are related to aircraft propulsion. The continuous market expansion attracts more and more the interest of researchers and industries towards the development of accurate numerical techniques to model thermodynamically the entire engine. This practice allows a performance and optimization analysis before the actual experimental testing, reducing the time and required investment in the design of a new engine. In this paper, a recently developed open source numerical tool named “Toolbox for the Modeling and Analysis of Thermodynamic Systems” (T-MATS) is used to assess …

Powder Compaction Simulation, Yuqi Fang, Caroline Baker, Marcial Gonzalez

The Summer Undergraduate Research Fellowship (SURF) Symposium

Powders are one of most manipulated materials in many industries such as food, pharmaceutical, energy and metallurgical industries. An important process for the powders is the compaction into solids with small porosity or high relative density. However, powders exhibit complex behavior during this process. After rearrangement and jamming of the powder bed, many types of deformation mechanisms dominate the compaction of granular materials, including elastic and plastic deformation of each individual particle. Therefore, having a better understanding of macroscale and microscale properties of powder beds and single particles during the compaction process is necessary. In addition, to reduce cost and …

Simulation And Validation Of Radio Frequency Heating Of Shell Eggs, Soon Kiat Lau

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Finite element models were developed with the purpose of finding an optimal radio frequency (RF) heating setup for pasteurizing shell eggs. Material properties of the yolk, albumen, and shell were measured and fitted into equations that were used as inputs for the model. When the egg was heated by itself, heating tend to be focused at the air cell to result in a “coagulation ring.” The focused heating near the air cell of the egg prevented satisfactory pasteurization of the egg, but deeper analysis of the simulation results offered a new perspective on how non-uniform RF heating could occur in …

Traction-Separation Relationships For Hydrogen-Induced Grain Boundary Embrittlement In Nickel Via Molecular Dynamics Simulations, Wesley Allen Barrows

Graduate Theses and Dissertations

The deleterious effects of atomic and molecular hydrogen on the mechanical properties of metals have long been observed. Although several theories exist describing the mechanisms by which hydrogen negatively influences the failure of materials, a consensus has yet to be reached regarding the exact mechanism or combination of mechanisms. Two mechanisms have gained support in explaining hydrogen’s degradative role in non-hydride forming metals: hydrogen-enhanced localized plasticity and hydrogen-enhanced decohesion. Yet, the interplay between these mechanisms and microstructure in metallic materials has not been explained. Accordingly, for this thesis, the three main objectives are: (i) to develop a numerical methodology to …

An Experimental Investigation On A Single Tubular Sofc For Renewable Energy Based Cogeneration System

Faculty of Engineering University of Malaya

Having negative impacts on environment and the scarcity of resources of conventional fossil fuels, fuel cell technology draws more attention as an alternative for providing the electrical energy in parallel with thermal energy. In this study, a single tubular solid oxide fuel cell (SOFC) with an electrolyte of Yttria-Stabilized Zirconia 8 mol% ceramic powder was experimentally investigated. The investigation illustrated the effects of three different fuel flow-rates (175 ml/min, 250 ml/min and 325 ml/min) and two operating temperatures (650 degrees C and 750 degrees C) on the output electrical and thermal powers. The highest electrical voltage (open circuit) and overall …

Optimizing The Robot Arm Movement Time Using Virtual Reality Robotic Teaching System

Faculty of Engineering University of Malaya

Robots play an important role in performing operations such as welding, drilling and screwing parts in manufacturing. Optimizing the robot arm movement time between different points is an important task which will minimize the make-span and maximize the production rate. But robot programming is a complex task whereby the user needs to teach and control the robot in order to perform a desired action. In order to address the above problem, an integrated 3-dimensional (3D) simulation software and virtual reality (VR) system is developed to simplify and speed up tasks and therefore enhance the quality of manufacturing processes. This system …

Aerospike Rocket Motor Structural Webbing, Andrew Brock

Master's Theses

A labscale hybrid rocket motor test stand has been developed for research at Cal Poly. The primary focus of research using this rig has been the development of regenerative cooling techniques using nitrous oxide as coolant and oxidizer, as well as validation of technologies relating to the annular aerospike nozzle. In order to prevent undesirable deflection of the cantilevered spike, a structural stiffening web, referred to as “The Spider,” is proposed. The Spider resembles a three-spoked wheel, with the aerospike held by the inner hub and the chamber walls abutting the outer radius.

The Spider, placed upstream of the nozzle, …

Advancement And Validation Of A Plug-In Hybrid Electric Vehicle Model Utilizing Experimental Data From Vehicle Testing, Kevin Lloyd Snyder

Wayne State University Theses

The objective of the research into modeling and simulation was to provide an iterative improvement to the Wayne State EcoCAR 2 team's math-based design tools for use in evaluating different outcomes based on hybrid powertrain architecture tweaks, controls code development and testing. This thesis includes the results of the team's work in the EcoCAR 2 competition for university student teams to create and test a plug-in hybrid electric vehicle for reducing petroleum oil consumption, pollutant emissions, and Green House Gas (GHG) emissions.

Plant model validations and advancements brought the vehicle plant model directionally closer to the actual vehicle's experimental data …

Eulerian-Lagrangian Analysis Of Solid Particle Distribution In An Internally Heated And Cooled Air-Filled Cavity

Faculty of Engineering University of Malaya

A parametric study has been conducted to investigate particle deposition on solid surfaces during free convection flow in an internally heated and cooled square cavity filled with air. The cavity walls are insulated while several pairs of heaters and coolers (HACs) inside the cavity lead to free convection flow. The HACs are assumed to be isothermal heat source and sinks with temperatures T-h and T-c (T-h > T-c). The problem is numerically investigated using the Eulerian-Lagrangian method. Two-dimensional Navier-Stokes and energy equations are solved using finite volume discretization method. Applying the Lagrangian approach, 5000 particles, distributed randomly in the enclosure, were …

Analytical And Numerical Validation Of Nozzle Spray Measurement Data Obtained From A Newly Developed Production System, Iddrisu Seidu

ETD Archive

A newly developed production test stand for measuring the spray angle of a pressure swirl atomizer was constructed and used to measure a product line of these pressure swirl atomizers -- the macrospray atomizer. This new test stand, utilizing constant temperature hot wire anemometers, captures the spray angle data based on the voltage drop the hot wire probes see as they traverse the spray cone of the atomizer and as fluid droplets impinge upon the wire. Datasets acquired from the experiments are compared and correlated with computational fluid dynamics (CFD) simulation data. In addition, angles obtained from another type of …

Dynamic Model Of A Non-Linear Pneumatic Pressure Modulating Valve Using Bond Graphs, Christopher L. Brubaker

ETD Archive

This research develops a mathematical model of the dynamic pressure response to a variable travel input of a pneumatic pressure modulating valve intended for use in a vehicle air brake system. Generically, the valve is a multi-domain system consisting of a mechanical portion and a pneumatic portion. Included in the mechanical portion of the model are compliance of the springs, inertia of the components, and resistance of the sliding components. The pneumatic portion of the model includes capacitance due to the compressibility of the gas, flow resistance through connected plumbing, and flow resistance through the valve control orifices. The development …

Combustion Kinetics Of Advanced Biofuels, Ghazal Barari

Electronic Theses and Dissertations

Use of biofuels, especially in automotive applications, is a growing trend due to their potential to lower greenhouse gas emissions from combustion. Ketones are a class of biofuel candidates which are produced from cellulose. However, ketones received rather scarce attention from the combustion community compared to other classes such as, alcohols, esters, and ethers. There is little knowledge on their combustion performance and pollutant generation. Hence their combustion chemistry needs to be investigated in detail. Diisopropyl ketone (DIPK) is a promising biofuel candidate, which is produced using endophytic fungal conversion. A detailed understanding of the combustion kinetics of the oxidation …

Modeling Crabbing Dynamics In An Electron-Ion Collider, A. Castilla, V. S. Morozov, T. Satogata, J. R. Delayen

Physics Faculty Publications

A local crabbing scheme requires π/2 (mod π) horizontal betatron phase advances from an interaction point (IP) to the crab cavities on each side of it. However, realistic phase advances generated by sets of quadrupoles, or Final Focusing Blocks (FFB), between the crab cavities located in the expanded beam regions and the IP differ slightly from π/2. To understand the effect of crabbing on the beam dynamics in this case, a simple model of the optics of the Medium Energy Electron-Ion Collider (MEIC) including local crabbing was developed using linear matrices and then studied numerically over multiple turns (1000 passes) …