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Life-Cycle Cost Analysis Of Alternative Reinforcement Materials For Bridge Superstructures Considering Cost And Maintenance Uncertainties, Christopher D. Eamon, Elin A. Jensen, Nabil F. Grace, Xiuwei Shi

Civil and Environmental Engineering Faculty Research Publications

A life cycle cost analysis (LCCA) was conducted on prestressed concrete bridges using carbon fiber reinforced polymer (CFRP) bars and strands. Traditional reinforcement materials of uncoated steel with cathodic protection and epoxy-coated steel were also considered for comparison. A series of deterministic LCCAs were first conducted to identify a range of expected cost outcomes for different bridge spans and traffic volumes. Then, a probabilistic LCCA was conducted on selected structures that included activity timing and cost random variables. It was found that although more expensive initially, the use of CFRP reinforcement has the potential to achieve significant reductions in life …

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 …

Contact Pressure Distribution Of Osteochondral Defects Of The Knee: Effects Of Non-Vertical Walls, Scott Ensminger

Wayne State University Theses

Purpose: To examine the relationship between well-shouldered osteochondral defects and

defects of different geometries by studying their effects on rim stress concentration and

load redistribution in the human knee.

Methods: Ten fresh-frozen cadaveric knees were mounted at 30° of flexion in a materials

testing machine. Digital electronic pressure sensors were placed in the medial and lateral

compartments of the knee. Dynamic pressure readings were recorded throughout the

loading and holding phases as each knee was loaded to 700N and held for 5 seconds.

Artificial defects were created in each knee to simulate well-shouldered defects and

beveled-defects. Loading was repeated for …

Free Vibration Analyses Of Abs (Acrylonitrile-Butadiene-Styrene) Rectangular Plates With Completely Free Boundary Conditions, Mehmet Akif Dundar

Wayne State University Theses

Acrylonitrile-Butadiene-Styrene (ABS) represents a family of engineering thermoplastics with a wide field of performance characteristics. ABS materials have been receiving a great deal of attention because of their unique properties, such as outstanding formability, high tensile strength and stiffness, very high impact strength, excellent ductility, excellent high and low temperature performance, and resistant to many chemicals and plasticizers. Particularly, ABS exhibits really high impact strength; therefore, it is used in industry products which require high impact strength materials, such as military helmets and construction safety helmets. The vibration analyses of ABS rectangular plates are incredibly significant for design in military …

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 …

Linear And Non-Linear Deformations Of A Wind Turbine Blade Considering Warping And All Aeroelastic Load Couplings, Fouad Mohammad Mohammad

Wayne State University Dissertations

The structural dynamics behavior of the blade of a horizontal axis wind turbine that reacts to the different components of the aerodynamic loading were studied by many researchers using different approaches and assumptions. In the present research, the author considered all the extensional, torsional and flexural loadings acting on the blade with their couplings, variable airfoil cross sections with warping effects, shear deflection, rotary inertia and with or without blade's pretwist for both the linear small deformation case and the nonlinear large deformation case. To the best knowledge of the author the simultaneous inclusion of all these factors has not …

Optical Investigation Of Ethanol And N-Heptane Dual-Fuel Partially Premixed Combution In S Reciprocating Engine, Radu Catalin Florea

Wayne State University Dissertations

The details of the dual-fuel combustion of n-heptane and ethanol were investigated in an optically accessible engine representative of light-duty applications. Experimental work involved the application of optical diagnostics such as high-speed imaging of combustion chemiluminescence and soot radiation, spectral measurements and laser induced fluorescence. At the same time, the experimental conditions have been replicated using numerical simulation of chemically reactive in-cylinder flow.

The numerical simulation results, which showed good agreement with the experimental data across several validation approaches, provided an improved understanding of the mechanism responsible for the control of the rate of combustion for dual-fuel operation. The comparison …

Investigation And Improvment Of Noise, Vibration And Harshness(Nvh) Properties Of Automotive Panels, Mohammad Al Zubi

Wayne State University Dissertations

ABSTRACT

INVESTIGATION AND IMPROVEMENT OF NOISE, VIBRATION AND HARSHNESS (NVH) PROPERTIES OF AUTOMOTIVE PANELS

by

MOHAMMAD AL-ZUBI

July 2012

Advisor: Dr. Emmanuel Ayorinde

Major: Mechanical Engineering

Degree: Doctor of Philosophy

The reduction of noise and vibration in and across several components and modules of the automotive, such as the panels, doors, engine covers, seats, and others, is of primary importance. The NVH performance may be a crucial factor in the purchase decisions of numerous buyers. This work investigates through experimental, analytical and computational methods, six groups of sample materials - fabric, foam, honeycomb, monolithic and sandwich, periodic cellular material structures …

Gapped Cantilever For The Enhancement Of Strain Sensitivity And Energy Efficiency, Qinglong Zheng

Wayne State University Dissertations

Cantilever structures have been widely used in a large variety of transducer applications. For cantilever based transducers, piezoresistive/piezoelectric mechanisms has always been a popular choice due to the advantages of being low cost, simple structure and portability. However, low sensitivity is recognized as a major disadvantage of these transducers compared with optical based measurement. In this research, a gapped cantilever structure is proposed to potentially increase the sensitivity by orders of magnitude. In order to guide the design, an advanced analytical model is developed, and the increased strain sensitivity is theoretically demonstrated. In addition, optimizations with this model interestingly reveal …

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 …

The Effect Of Biodiesel Blends On A Multi-Cylinder Engine And The Impact On Aftertreatment, Amy Peterson

Wayne State University Dissertations

Recently, topics including global warming, increased environmental awareness, recycling, and organically produced meat and vegetables have been prevalent in the media and research arenas. The rapidly increasing cost for fossil fuels and the pursuit of environmental conservation has brought about the interest in a renewable and clean burning fuel, specifically biodiesel. Biodiesel, or vegetable oil ester as it was originally referred to, has been improving and progressing since the early 1900's. Fortunately, significant advancement in the understanding of raw vegetable oil as a fuel as well as converting it to ethyl or methyl esters, now known as biodiesel, has been …