Engineering Commons^™

Optimization And Comparison Of Over-Expanded And Other High Efficiency Four-Stroke Spark-Ignited Boosted Engines, Zhuyong Yang

Dissertations, Master's Theses and Master's Reports

Recent fuel economy and emission regulations are the major concern of the research and development of modern internal combustion engine. Such technologies include variable valve timing (VVT), direct injection (DI), turbocharging, downsizing, and over-expanded cycle are used by many manufacturers to improve engine fuel economy or increase power density.

Current Atkinson cycle technology in the production engine is mainly realized by an advanced valvetrain system to reduce the effective compression ratio while maintaining the same expansion ratio. Another approach to realize over-expanded cycle engine is to utilize a multi-link cranktrain mechanism. Although the Atkinson cycle was originally patented in the …

A Hybrid-Powered Wireless System For Multiple Biopotential Monitoring, Shawn Li

Dissertations, Master's Theses and Master's Reports

Chronic diseases are the top cause of human death in the United States and worldwide. A huge amount of healthcare costs is spent on chronic diseases every year. The high medical cost on these chronic diseases facilitates the transformation from in-hospital to out-of-hospital healthcare. The out-of-hospital scenarios require comfortability and mobility along with quality healthcare. Wearable electronics for well-being management provide good solutions for out-of-hospital healthcare. Long-term health monitoring is a practical and effective way in healthcare to prevent and diagnose chronic diseases. Wearable devices for long-term biopotential monitoring are impressive trends for out-of-hospital health monitoring. The biopotential signals in …

Influence Of Micro-Nucleate Boiling On Annular Flow Regime Heat Transfer Coefficient Values And Flow Parameters – For High Heat-Flux Flow Boiling Of Water, Soroush Sepahyar

Dissertations, Master's Theses and Master's Reports

Analysis of results from steady and steady-in-the-mean high heat-flux (15 - 70 W/cm², with water as working fluid) shear driven annular flow-boiling experiments presented here - and low heat-flux (0.1- 1 W/cm², with FC-72 as working fluid) experiments presented elsewhere – together lead to a key conclusion. The conclusion is that heat carrying nucleation rates go often undetected by the typically used visualization approaches for flow boiling – as such flows often involve µm- to sub- µm scale bubble diameters in millimeter-scale ducts. These nucleation rates play a significant role in most of the so-called convective …

Modeling Of Thermal Dynamics In Chevrolet Volt Gen Ii Hybrid Electric Vehicle For Integrated Powertrain And Hvac Optimal Operation Through Connectivity, Nehal Doshi

Dissertations, Master's Theses and Master's Reports

Integrated thermal energy management across system level components in electric vehicles (EVs) and hybrid electric vehicles (HEVs) is currently an under explored space. The proliferation of connected vehicles and accompanying infrastructure in recent years provides additional motivation to explore opportunities in optimizing thermal energy management in EVs and HEVs with the help of this newly available connected vehicle data. This thesis aims to examine and analyze the potential to mitigate vehicle energy consumption and extend usable driving range through optimal control strategies which exploit physical system dynamics via controls integration of vehicle subsystems.

In this study, data-driven and physics-based models …

Networked Microgrid Optimization And Energy Management, Robert S. Jane

Dissertations, Master's Theses and Master's Reports

Military vehicles possess attributes consistent with a microgrid, containing electrical energy generation, storage, government furnished equipment (GFE), and the ability to share these capabilities via interconnection. Many military vehicles have significant energy storage capacity to satisfy silent watch requirements, making them particularly well-suited to share their energy storage capabilities with stationary microgrids for more efficient energy management. Further, the energy generation capacity and the fuel consumption rate of the vehicles are comparable to standard diesel generators, for certain scenarios, the use of the vehicles could result in more efficient operation. Energy management of a microgrid is an open area of …

Paddle Mixer-Extrusion Reactor For Torrefaction And Pyrolysis, Stas Zinchik

Dissertations, Master's Theses and Master's Reports

This work is focused on the fundamental understanding and the development of paddle mixer reactors (or modified screw augers). This work will contribute to the effort of the thermal conversion of biomass and wastes. We developed and studied two paddle systems (i) 25-mm lab-scale (up to 1 kg/hr) and (ii) 101-mm pilot-scale (up to 100 kg/hr). Thermal behavior of the two systems was studied and it was estimated that the lab-scale system has a high heating rate of up to 530 °C/s. Residence times were thoroughly measured and were determined as a function of rotation frequency and volume fraction. We …

Development Of A Fused Deposition 3d Printed Buoy And Method For Quantifying Wave Tank Reflections, Samantha G. Swartzmiller

Dissertations, Master's Theses and Master's Reports

Testing model scale prototypes is integral to the development of wave energy converter (WEC) technology. Model scale WECs are tested in wave tanks where they are subjected to repeatable wave fields. Their presence in water creates radiated waves that eventually reflect off tank walls disrupting the intended wave field. Fabrication of model scale WECs is another developing aspect of tank testing. Often model WECs are built of foam. Additive manufacturing is a promising alternative although the most common method, fused deposition modeling (FDM) 3D printing, does not typically produce waterproof parts. The goals of this work were 1) develop a …

Optimization And Control Of Arrays Of Wave Energy Converters, Jianyang Lyu

Dissertations, Master's Theses and Master's Reports

Wave Energy Converter Array is a practical approach to harvest ocean wave energy. To leverage the potential of the WEC array in terms of energy extraction, it is essential to have a properly designed array configuration and control system. This thesis explores the optimal configuration of Wave Energy Converters (WECs) arrays and their optimal control. The optimization of the WEC array allows both dimensions of individual WECs as well as the array layout to varying. In the first optimization problem, cylindrical buoys are assumed in the array where their radii and drafts are optimization parameters. Genetic Algorithms are used for …