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Gearbox Baffle Optimization, Megan Arduin Dec 2019

Gearbox Baffle Optimization, Megan Arduin

Master's Theses

Current literature reveals there is limited consensus on the placement of baffles within a gearbox to reduce churning losses. Thus, there is a need for a process to identify baffle clearances that result in maximum and minimum churning losses. There are two types of baffles: axial and radial. While both axial and radial baffles cause reductions in churning losses to various degrees, the focus is on the effect of radial baffles. The effect of a board (rectangular plate) baffle location on the churning losses of a single gear gearbox are evaluated using computational fluid dynamics (CFD) implemented in Ansys. Several ...


Estimation Of The Fatigue Life Of Additively Manufactured Metallic Components Using Modified Strain Life Parameters Based On Surface Roughness, Peter Grohs Dec 2019

Estimation Of The Fatigue Life Of Additively Manufactured Metallic Components Using Modified Strain Life Parameters Based On Surface Roughness, Peter Grohs

Master's Theses

In this study, a method is developed to estimate the effects of surface roughness on the fatigue life of additively manufactured titanium Ti6Al4V, aluminum 7075–T6, and steel 4340 alloys through modified strain life parameters using finite element analysis (FEA). This method is highly beneficial to the fatigue analysis of as-built additively manufactured metal components, which possess rough surfaces that reduce fatigue life significantly but are challenging to analyze directly using finite element simulation because of complex geometries, i.e., modeling an exact surface profile is arduous.

An effective stress concentration factor, incorporating roughness data, is defined to quantify their ...


Application Of Elastodynamic Finite Integration Technique (Efit) To Three-Dimensional Wave Propagation And Scattering In Arbitrary Geometries, Sean M. Raley Aug 2019

Application Of Elastodynamic Finite Integration Technique (Efit) To Three-Dimensional Wave Propagation And Scattering In Arbitrary Geometries, Sean M. Raley

Master's Theses

Over several decades, railroad Ultrasonic Testing (UT) industry techniques have primarily been developed through simple analytical modelling and experimental approaches. However, with present-day computational capabilities, we can use numerical techniques like the Elastodynamic Finite Integration Technique (EFIT) to fine-tune systems for complex applications before the fabrication process begins. EFIT is well-established as a useful method in numerical analysis of ultrasonic wave propagation with distinct advantages over the Finite Difference Time Domain method. Several software packages exist that use EFIT as the primary method for simulating the behavior of ultrasonic waves over time in 2 or 3 dimensions, but none of ...


A Study Of The Mono-Stable And Bi-Stable Magnetic Spring Based Vibration Energy Harvesters Subject To Harmonic Excitation, Hieu Tri Nguyen Aug 2019

A Study Of The Mono-Stable And Bi-Stable Magnetic Spring Based Vibration Energy Harvesters Subject To Harmonic Excitation, Hieu Tri Nguyen

Master's Theses

Continuous improvement in electronics manufacturing has led to the deployment of low-power sensors, which has resulted in an urgent need for developing energy harvesters capable of generating electric power using abundant and free energy sources such as ambient vibrations. The work presented here is motivated by the growing interest in targeting nonlinear energy harvesting through magnetic interactions, which are compatible with ambient vibration energy sources that are often characterized by a broadband frequency spectrum and can be particularly rich with low frequencies. In this work, experimental and theoretical studies were performed to investigate a magnetic- levitation-based vibration energy harvester that ...


Surface Engineering Solutions For Immersion Phase Change Cooling Of Electronics, Brendon M. Doran May 2019

Surface Engineering Solutions For Immersion Phase Change Cooling Of Electronics, Brendon M. Doran

Master's Theses

Micro- and nano-scale surface modifications have been a subject of great interest for enhancing the pool boiling heat transfer performance of immersion cooling systems due to their ability to augment surface area, improve wickability, and increase nucleation site density. However, many of the surface modification technologies that have been previously demonstrated show a lack of evidence concerning scalability for use at an industrial level. In this work, the pool boiling heat transfer performance of nanoporous anodic aluminum oxide (AAO) films, copper oxide (CuO) nanostructure coatings, and 1D roll-molded microfin arrays has been studied. Each of these technologies possess scalability in ...


Effects On Strength And Corrosive Characteristics Of Hardened Cement Paste Using Rice Husk And Sugarcane Bagasse, Travis D. Garrett May 2019

Effects On Strength And Corrosive Characteristics Of Hardened Cement Paste Using Rice Husk And Sugarcane Bagasse, Travis D. Garrett

Master's Theses

Cement is one of the most used building materials in the world. The production of ordinary Portland cement contributes to the release of harmful greenhouse gasses. In an effort to reduce these emissions, different materials are being evaluated for their use as partial replacements for ordinary Portland cement. Rice husk and sugarcane bagasse are agricultural waste products and large amounts of these are currently landfilled, making them inexpensive and available. When combusted at high temperatures they form rice husk ash and sugarcane bagasse ash that have pozzolanic characteristics. The high silicon dioxide in these products makes them good options to ...


Training Set Density Estimation For Trajectory Predictions Using Artificial Neural Networks, Zachary Reinke Apr 2019

Training Set Density Estimation For Trajectory Predictions Using Artificial Neural Networks, Zachary Reinke

Master's Theses

Demand on earth orbiting surveillance systems in increasing as more equipment is put into orbit. These systems rely on predictive techniques to periodically track objects. The demand on these systems may be reduced if object trajectory data to develop scalable training sets used for training artificial neural networks (ANNs) to predict trajectories of a dynamic system. These methods use multi-variable statistics to analyze data energy content to provide the ANN with low density, feature-rich, training data. The developed techniques have been shown to increase ANN prediction accuracy while reducing the size of the training set when applied to a linear ...


Modeling And Simulation With Optimal Gear Ratio For A Forward-Looking, Velocity-Driven, Power-Split Hybrid Electric Vehicle, Sonal Babasaheb Kanap Apr 2019

Modeling And Simulation With Optimal Gear Ratio For A Forward-Looking, Velocity-Driven, Power-Split Hybrid Electric Vehicle, Sonal Babasaheb Kanap

Master's Theses

Increases in vehicle demand and fossil fuel consumption are major contributors to environmental problems, such as air pollution and climate change. This has led to research on alternative, energy-efficient vehicle technologies. Automobile users are now preferring comfortable vehicles with minimal fuel consumption and with more efficient engines. Hybrid cars are becoming common because of their advantage of running cleaner and with better gas mileage. A hybrid car runs on the power of both an electric motor and a gasoline engine. This mechanism helps cut fuel consumption and conserve energy. An additional advantage is a regenerative braking system that helps recharge ...


Optimal Energy Management For Forward-Looking Serial-Parallel Hybrid Electric Vehicle Using Rule-Based Control Strategy, Abhijit Bhaskar Jadhav Apr 2019

Optimal Energy Management For Forward-Looking Serial-Parallel Hybrid Electric Vehicle Using Rule-Based Control Strategy, Abhijit Bhaskar Jadhav

Master's Theses

In today’s sophisticated era of technology, resolving environmental problems is a matter of grave concern. Developing hybrid electric vehicles is a good step towards environmental preservation, since they use less fuel compared to conventional vehicles because of the combination of electric and mechanical energy. A hybrid electric vehicle reduces dependence on fossil fuels and hence lowers emissions. Specifically, a hybrid powertrain that includes a conventional gasoline engine and a brushless DC motor offers great potential to meet stringent CO2 regulations and fuel economy requirements. This thesis focuses on the effects of initial state of charge (SOC) stored in ...