Engineering Commons^™

Spectral Methods For Hamiltonian Systems And Their Applications, Lewei Zhao

Wayne State University Dissertations

Hamiltonian systems typically arise as models of conservative physical systems and have many applications. Our main emphasis is using spectral methods to preserve both symplectic structure and energy up to machine error in long time. An engery error estimation is given for a type of Hamiltonian systems with polynomial nonlinear part, which is numerical verified by solving a Henon-Heiles systems. Three interesting applications are presented : the first one is the N-body problems. The second one is approximation for Weyl's Law and the third one is simulating quantum cooling in an optomechanical system to study the dissipative dynamics. Moreover, nonsmooth …

Developing A Real-World Vehicle Trip Dataset Through Public Travel Surveys And Applying It To Battery Electric Vehicle Performance Study, Nizar Ali Khemri

Wayne State University Dissertations

Real-world second-by-second vehicle driving cycle data is very important for research and development of the traditional fuel-powered vehicles, the emerging electric vehicles, and the hybrid vehicles. A project solely dedicated to generating such information would be extremely costly and time-consuming. Alternatively, we introduce a method to develop such a database by utilizing two publicly available passenger vehicle travel surveys; the 2004-2006 Puget Sound Regional Commission (PSRC) Travel Survey and the 2011 Atlanta Regional Commission (ARC) Travel Survey. The two surveys complement each other – the former is in low time resolution but covers vehicle driving and non-driving operation for over …

An Effective Methodology For Suppressing Structure-Borne Sound Radiation, Lingguang Chen

Wayne State University Dissertations

ABSTRACT

AN EFFECTIVE METHODOLOGY FOR SUPPRESSING

STRUCTURE-BORNE SOUND RADIATION

by

LINGGUANG CHEN

December 2017

Advisor: Dr. Sean F. Wu

Major: Mechanical Engineering

Degree: Doctor of Philosophy

This dissertation is primarily concerned with the development of an effective methodology for reducing structure-borne sound radiation from an arbitrarily shaped vibrating structure. There are three major aspects that separate the present methodology from all the previous ones. Firstly, it is a non-contact and non-invasive approach, which is applicable to a class of vibrating structures encountered in engineering applications. Secondly, the input data consists of a combined normal surface velocity distribution on a portion …

Biomechanics Of Concussion: The Importance Of Neck Tension, Ron Jadischke

Wayne State University Dissertations

Linear and angular velocity and acceleration of the head are typically correlated to concussion. Despite improvements in helmet performance to reduce accelerations, a corresponding reduction in the incidence of concussion has not occurred (National Football League [NFL] 1996 – present).

There is compelling research that forces on and deformation to the brain stem are related to concussion. The brain stem is the center of control for respiration, blood pressure and heart rate and is the root of most cranial nerves. Injury to the brain stem is consistent with most symptoms of concussion reported in the National Football League and the …

Development Of A Finite Element Pelvis And Lower Extremity Model With Growth Plates For Pediatric Pedestrian Protection, Ming Shen

Wayne State University Dissertations

Finite element (FE) model is a useful tool frequently used for investigating the injury mechanisms and designing protection countermeasures. At present, no 10 years old (YO) pedestrian FE model has been developed from appropriate anthropometries and validated against limitedly available impact response data. A 10 YO child FE pelvis and lower extremities (PLEX) model was established to fill the gap of lacking such models in this age group. The baseline model was validated against available pediatric postmortem human subjects (PMHS) test data and additional scaled adult data, then the PLEX model was integrated to build a whole-body FE model representing …

Toward Human-Like Automated Driving: Learning Spacing Profiles From Human Driving Data, Syed Ali

Wayne State University Dissertations

For automated driving vehicles to be accepted by their users and safely integrate with traffic involving human drivers, they need to act and behave like human drivers. This not only involves understanding how the human driver or occupant in the automated vehicle expects their vehicle to operate, but also involves how other road users perceive the automated vehicle’s intentions. This research aimed at learning how drivers space themselves while driving around other vehicles. It is shown that an optimized lane change maneuver does create a solution that is much different than what a human would do. There is a need …

Development Of An Elderly Female Torso Finite Element Model For Restraint System Research And Development Applications, Anil Kalra Kalra

Wayne State University Dissertations

Elderly females are found to be one of the most vulnerable segments of population during motor vehicle crashes and their population is increasing in the coming decades. Current design of restraint systems as well as other passive safety measures are designed based on anthropomorphic details of younger population. Developing another dummy representing elderly female population is a costly effort, while a finite element (FE) model of elderly female with similar anthropomorphic details and age- and gender-specific material properties can be a better alternative solution. The current research focuses on the development of a FE model of an elderly female torso, …

Static And Dynamic Behavior Of Carbon Fiber Reinforced Aluminum (Carall) Laminates, Gurpinder Singh Dhaliwal

Wayne State University Dissertations

STATIC AND DYNAMIC BEHAVIOUR OF CARBON FIBER REINFORCED ALUMINUM (CARALL) LAMINATES

by

GURPINDER SINGH DHALIWAL

Advisor: Dr. Golam Newaz

Major: Mechanical Engineering

Degree: Doctor of Philosophy

The main aim of this research work was to investigate the static and dynamic properties of carbon fiber reinforced aluminum laminates cured without using any external adhesive and acid treatment of aluminum layers. A comprehensive study was undertaken to study the effect of adding epoxy resin rich polyester synthetic surface veil cloth layers on the failure modes and flexural and tensile response of these fiber metal laminates (FMLs). The main purpose of adding veil …

Arbitrary Lagrangian-Eulerian Method Investigation On Fuel Tank Strap Simulation Under Proving Ground Condition, Guangtian Song

Wayne State University Dissertations

The Arbitrary Lagrangian-Eulerian (ALE) is a hybrid finite element formulation that can alleviate many of the drawbacks from the traditional Lagrangian-based and Eulerian-based finite element simulations, which is developed through combining modern algorithms for Lagrangian hydrodynamics, meshing technology and remap methods developed for high-resolution Eulerian methods. Lagrangian-based finite element formulations is that the computational system moves with the material and main drawback is that it will face severe problems to deal with strong distortions in the computational domain. Eulerian-based finite element formulations is that the computational system is a prior fixed in space and unable to deal easily with fluids …

Pedestrian Head Protection During Car To Pedestrian Accidents: In The Event Of Primary Impact With Vehicle And Secondary Impact With Ground, Vishal Gupta

Wayne State University Dissertations

Current regulations for assessing pedestrian safety use a simplified test setup that ignores many real-world factors. In particular, the level of protection is assessed using a free-motion headform impacting the vehicle's hood at a fixed angle. As such, this test setup does not capture the effect due to the vehicle front-end profile, nor does it comprehend injury due to a possible secondary impact of the pedestrian's head with ground. This thesis aims to numerically simulate vehicle to pedestrian crashes to develop knowledge that may suggest ways to improve safety above and beyond the regulatory tests. Inputs to the simulations include …

Combustion Visualization And Particulate Matter Emission Of A Gdi Engine By Using Gasoline And E85, Po-I Lee

Wayne State University Dissertations

In order to increase engine efficiency as well as to reduce emission, optimizing combustion is always the challenge in research and product development. Gasoline direct injection (GDI) engines have been popularized due to its higher power density, fuel efficiency, and the possibility for advanced engine technologies over conventional port-fuel-injection (PFI) gasoline engines. However, many issues are heavily investigated, such as air-fuel mixing preparation, fuel wall-wetting, higher HC and PM emissions, catalytic convertor efficiency, knocking, and pre-ignition. Besides, advanced technologies represent higher production cost.

Because of the limited resource of petroleum-based fuels, ethanol is deemed as the alternative fuel for gasoline …

Effect Of Intake Temperature And Boost Pressure On The Auto-Ignition Of Fuels With Different Cetane Numbers And Volatilities, Chandrasekharan Jayakumar

Wayne State University Dissertations

The aim of this research is to investigate the effect of air inlet temperature and boost pressure on the auto-ignition of fuels that have different CNs and volatilities in a single cylinder diesel engine. The inlet air temperature is varied over a range of 30°C to 110°C at a constant intake pressure of 1.1 bar. The boost pressure is varied from 1.1 bar to 1.5 bar at a constant intake temperature of 60°C. All engine tests are run at steady-state conditions. The fuels used are ultra-low-sulfur-diesel (ULSD), JP-8 (two blends with CN 50 & 31) and F-T SPK. Detailed analysis …

Simulations And Experiments Of Fuel Injection, Mixing And Combustion In Di Gasoline Engines, Yi Zheng

Wayne State University Dissertations

Direct Injection (DI) has been known for its improved performance and efficiency in gasoline spark-ignition engines. In order to take all the advantages of the GDI technology, it is important to investigate in detail the interactions of fuel spray and combustion system, such as air-fuel mixing, in-cylinder flow development, surface wetting, and turbulence intensity. The characterizations of the internal nozzle flow of DI injector are first studied using the multidimensional computational fluid dynamic (CFD) simulation. In the meanwhile the numerical and experimental studies are carried out to observe the external spray and wall impingements in an optical constant volume vessel. …

Ionization In Diesel Combustion For On-Board Diagnostics And Engine Control, Tamer Hassan Badawy

Wayne State University Dissertations

Diesel engines have been known for their high thermal efficiency and specific power output, but there is concern about engine-out NOx and particulate matter emissions. To meet the current emission standards, advanced diesel engines are fitted with electronically controlled fuel injection systems and sophisticated and expensive after-treatment devices. Further improvements are still needed to meet future goals in better fuel economy and the more stringent emission standards. In order to meet these goals, there is a need for the control of the combustion process to reduce engine-out emissions in real-time and reduce the demand on the after-treatment devices. This requires …

Multi-Fuel Operation Of Modern Engines; On Board Fuel Identification, Florin Mocanu

Wayne State University Dissertations

Modern engines require enhancement of electronic controls to achieve better fuel economy, higher power density and satisfactory emissions levels while operating safely.

Military vehicles should be capable to run safely and efficiently on any fuel available in the field, therefore on-board fuel identification and adaptation of engine controls to the type of fuel becomes extremely important. In these conditions, the use of an inexpensive, nonintrusive sensor is highly desirable.

The development of a technique based on the measurement of the instantaneous crankshaft speed and engine dynamics could be a convenient solution.

Several such methods have been elaborated at the Center …

An Integrated Framework For Configurable Product Assortment Planning, Seyed Ali Taghavi Behbahani

Wayne State University Dissertations

A manufacturer's assortment is the set of products or product configurations that the company builds and offers to its customers. While the literature on assortment planning is growing in recent years, it is primarily aimed at non-durable retail and grocery products. In this study, we develop an integrated framework for strategic assortment planning of configurable products, with a focus on the highly complex automotive industry. The facts that automobiles are highly configurable (with the number of buildable configurations running into thousands, tens of thousands, and even millions) with relatively low sales volumes and the stock-out rates at individual dealerships (even …

Intricate Dynamics And Hydrodynamic Frictional Losses Of The Piston-Ring Assembly In Internal Combustion Engines, Mohannad Hakeem

Wayne State University Dissertations

Frictional losses in internal combustion engines approximately account for 10% of the expended fuel energy. Moreover, forty percent of these losses are attributed to the reciprocating motion of the piston-assembly. Besides the adverse effect of friction on fuel economy, the intricate dynamics of the piston-assembly tend to significantly influence the thermal efficiency through blow-by, the engine durability through wear, and the engine noise through piston-slap. Moreover, 40 to 80% of the lubricant oil consumption has been attributed to the ring-pack dynamics.

In this dissertation, a reliable tool has been developed using MATLAB/SIMULINK and embedded C-S Functions that predicts the intricate …

Numerical Simulation And Experimentation Of Pulsatile Flows In Axisymmetric Arterial Models, Tadesse Gebreegziabher

Wayne State University Dissertations

ABSTRACT

NUMERICAL SIMULATION AND EXPERIMENTATION OF PULSATILE FLOWS IN AXISYMMETRIC ARTERIAL MODELS

by

TADESSE GEBREEGZIABHER

December 2011

Co-advisors: 1. Dr. Emmanuel Ayorinde 2. Dr. Trilochan Singh

Major: Mechanical Engineering

Degree: Doctor of Philosophy

The primary motivation for this dissertation is the fluid flow and structural response to unsteady blood flow in the human body. The research work is a synergistic merging of numerical simulation and experimentation. For the experiments, an all-encompassing, highly flexible experimental apparatus was designed and fabricated to facilitate a wide range of operating conditions, the range of which was chosen to accommodate mammalian cardiovascular system for both …

Spray Characterization Of Flex-Fuel Gasoline Di Injectors And Spray Interaction With Charge Motion In A Variable Valve Actuation Engine, Atsushi Matsumoto

Wayne State University Dissertations

The objective of this study is to understand the characteristics of GDI sprays and behavior of in-cylinder charge motion in a GDI engine which is equipped with variable valve actuation. High speed spray visualization in a spray chamber was conducted for a study of spray development. By Schlieren visualization technique, the effect of different conditions including ambient conditions (temperature, pressure) and injection conditions (fuel type, fuel temperature, nozzle design) on spray formation was discussed in both qualitative and quantitative methods. High-speed visualization of the in-cylinder charge motion was carried out as well using an optical accessible engine. The testing was …

Throughput Analysis And Bottleneck Management Of Production Lines, Hatice Ucar

Wayne State University Dissertations

Companies are increasing their manufacturing excellence in order to stay competitive in the globalizing market. Plants are becoming more complex year by year due to increasing product classes, hardware complexity, etc... The design and operation of manufacturing systems is of greater importance today than it was in the past. Many studies have been carried out on the design and operation of manufacturing systems by academicians and practitioners over the years, however, there is still no agreement on how to best predict and improve the factory performance (Gershwin, 2000). The studies are based on either analytical approaches or simulation-based approaches. Success …

Finite Element Reconstruction Of Real World Aortic Injury In Near-Side Lateral Automotive Crashes With Conceptual Countermeasures, Aditya Neelakanta Belwadi

Wayne State University Dissertations

Traumatic rupture of the aorta (TRA) remains the second most common cause of death associated with motor vehicle crashes after brain injury. On an average, nearly 8,000 people die annually in the United States due to blunt injury to the aorta. It is observed that more than 80% of occupants who suffer an aortic injury die at the scene due to exsanguination into the chest. With the advent of more accurate and established human body finite element (FE) models, FE crash reconstruction methods may become a valuable tool when assessing crash scenarios and occupant injury mechanisms.

The current study is …