Engineering Commons^™

College Of Engineering Senior Design Competition Fall 2010, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge.

The senior design competition helps to focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects …

Experimental And Computational Analysis Of An Energy Storage Composite Ankle Foot Orthosis, Michelle C. Hawkins

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ankle Foot Orthotics (AFOs) are used by individuals presenting with Charcot-Marie-Tooth (CMT) to assist with improving gait. Mitch Warner, CPO, has developed a composite AFO made from woven carbon-Kevlar and carbon fiber lamina. The overall goals of the research are to characterize the HELIOS brace and to determine its effect on the gait of CMT subjects. Human motion analysis, experimental mechanical testing, and Finite Element Analysis (FEA) are used to gain a better understanding of how the materials and geometric design of the HELIOS AFO contribute to gait.

Human motion experiments are performed to determine the relationship between ground reaction …

Computational Analysis For Improved Design Of An Sae Baja Frame Structure, Nagurbabu Noorbhasha

UNLV Theses, Dissertations, Professional Papers, and Capstones

Baja SAE is an intercollegiate competition to design, fabricate, and race a small, single passenger, off-road vehicle powered by a 10 HP Briggs & Stratton 4-Stroke gasoline engine. All Baja SAE vehicles for the competition are powered by a small engine, thus large part of vehicle performance depends on the acceleration and maneuverability of the vehicle which is proportional to the weight of the chassis and rollcage. As weight is critical to achieve the greater performance of the vehicle, a balance must be found between the strength and weight of the rollcage to ensure the safety of the driver.

The …

Impact Investigation Of Reactor Fuel Operating Parameters On Reactivity For Use In Burnup Credit Applications, Tanya N. Sloma

UNLV Theses, Dissertations, Professional Papers, and Capstones

When representing the behavior of commercial spent nuclear fuel (SNF), credit is sought for the reduced reactivity associated with the net depletion of fissile isotopes and the creation of neutron-absorbing isotopes, a process that begins when a commercial nuclear reactor is first operated at power. Burnup credit accounts for the reduced reactivity potential of a fuel assembly and varies with the fuel burnup, cooling time, and the initial enrichment of fissile material in the fuel. With regard to long-term SNF disposal and transportation, tremendous benefits, such as increased capacity, flexibility of design and system operations, and reduced overall costs, provide …

User's Guide To Mbc3: Multi-Blade Coordinate Transformation Code For 3-Bladed Wind Turbine, G. S. Bir

Publications (E)

The dynamics of wind turbine rotor blades are conventionally expressed in rotating frames attached to the individual blades. The tower-nacelle subsystem though, sees the combined effect of all rotor blades, not the individual blades. Also, the rotor responds as a whole to excitations such as aerodynamic gusts, control inputs, and tower-nacelle motion—all of which occur in a nonrotating frame. Multi-blade coordinate transformation (MBC) helps integrate the dynamics of individual blades and express them in a fixed (nonrotating) frame. MBC involves two steps: transforming the rotating degrees of freedom and transforming the equations of motion. Reference 1 details the MBC operation. …

Wind Flow Modeling For Wind Energy Analysis Of The Nellis Dunes Area In Nevada, Upendra Rangegowda

UNLV Theses, Dissertations, Professional Papers, and Capstones

A wind energy analysis of the Nellis Dunes area in Nevada was conducted. A DEM file which contains the elevation data was used to generate the surface model and to create a 3-D mesh of the region. Local meteorological tower data collected for a period of one year was used to generate the diagnostic initial wind fields. Upper level wind fields were created using a surface boundary layer technique along with linear interpolation of the tower level wind fields. The vertical components of the velocities were adjusted using the equation of continuity. Mass consistent 3-D wind fields were then calculated …

Optimal Design Of Vehicle With Internal Space Frame Structure Subjected To High Impact Load, Jagadeep Thota

UNLV Theses, Dissertations, Professional Papers, and Capstones

Armored military vehicles are heavily used in modern warfare. These vehicles are subjected to lethal attacks from projectiles and land mines. The shocks from these attacks may risk the safety of the occupants and damage the electronic instruments within the vehicle. Extensive research on the analysis and reduction of shocks on civilian vehicles has been performed. Fewer researchers addressed these problems in the case of military vehicles. Space frames are usually used to enhance structural strength of the vehicle while reducing its overall weight. These frames comprise of beams connected together at joints. Recently, space frames were incorporated in military …

Field Measurement & Verification Of Residential Duct Leakage Methods And Cfd Analysis Of Hvac Mixing Box, Uday Vadlamani

UNLV Theses, Dissertations, Professional Papers, and Capstones

The research work in this thesis is subdivided to providing the initial results of the experimental work followed by simulation work at the end. The experimental work proposes a new measurement technique for measuring total and local leakages in ducts. The experimental work in this research tries to focus effort on finding the approximate locations of leaks in the HVAC residential duct systems to direct better the effort of duct sealing. This technique can provide several advantages over existing techniques. It will eventually have a greater potential to locate leaks so that retrofitting in ducts can be focused on leaky …

Development Of Hydrogen Direct Injection For Conversion Of Internal Combustion Engines, Maxwell A. Wilson

UNLV Theses, Dissertations, Professional Papers, and Capstones

The trend toward usage of vehicles that operate on alternative, renewable forms of energy storage has generated areas for development of new products that will facilitate implementation of new automotive fuel systems. As the reality of a hydrogen-fueled economy emerges, intermediate technologies may be necessary for the transition between hydrocarbon fueled internal combustion engines and hydrogen powered fuel cells. The University of Nevada Las Vegas Center for Energy Research has developed a method for converting the common hydrocarbon fueled internal combustion engine to hydrogen direct injected fueling. This thesis describes the second phase of development and involves the design, fabrication …

Mechanical Behavior Of Alloy 230 At Temperatures Relevant To Ngnp Program, Sudin Chatterjee

UNLV Theses, Dissertations, Professional Papers, and Capstones

Identification and selection of suitable structural materials for heat exchanger application within the purview of the next generation nuclear plant (NGNP) program constitute a major challenge. This challenge stems from the lack of many desired metallurgical and mechanical properties of conventional metallic materials and alloys for applications at temperatures approaching 950 oC. Nickel (Ni)-base Alloy 230 has been highly recommended as a suitable structural material for such application due to its excellent resistance to high-temperature plastic deformation and superior corrosion resistance in many hostile environments. Systematic studies on tensile, fracture toughness, creep, stress-rupture and creep-fatigue behavior of this alloy have …

Experimental And Numerical Analysis Of Structures With Bolted Joints Subjected To Impact Load, Kumarswamy K. Nakalswamy

UNLV Theses, Dissertations, Professional Papers, and Capstones

The aim of this study is to analyze the transient behavior of structures with bolted joints subjected to impact or shock loads using experimental methods and Finite Element Analysis (FEA). Various factors that affect the response of the bolted joint structures for shock loading were studied, such as damping, preload, intensity of impact load and type of FE modeling. The objective of this work was to develop computational modeling procedures that provide structural analysts an improved physics-based shock model for combat vehicles focusing mainly on shock transmission across bolted joints. There is only a limited amount of published literature describing …

College Of Engineering Senior Design Competition Spring 2010, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Each student in his or her senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. The senior design project encourages the student to use everything learned in the engineering program to create a practical, real-world solution to an engineering challenge.

A highlight of the year-long senior design project is the senior design competition. This competition, which usually takes place the week before finals each semester, helps focus the senior students on increasing the quality and potential for commercial application for their design projects.

Judges from local industry evaluate the projects on innovation, commercial …

Solar Power And The Electric Grid, Energy Analysis, Nrel Energy Analysis

Publications (E)

In today’s electricity generation system, different resources make different contributions to the electricity grid. This fact sheet illustrates the roles of distributed and centralized renewable energy technologies, particularly solar power, and how they will contribute to the future electricity system. The advantages of a diversified mix of power generation systems are highlighted.

Technology Improvement Pathways To Cost-Effective Vehicle Electrification: Preprint, A. Brooker, M. Thornton, J. Rugh

Publications (T)

Electrifying transportation can reduce or eliminate dependence on foreign fuels, emission of green house gases, and emission of pollutants. One challenge is finding a pathway for vehicles that gains wide market acceptance to achieve a meaningful benefit. This paper evaluates several approaches aimed at making plug-in electric vehicles (EV) and plug-in hybrid electric vehicles (PHEVs) cost-effective including opportunity charging, replacing the battery over the vehicle life, improving battery life, reducing battery cost, and providing electric power directly to the vehicle during a portion of its travel. Many combinations of PHEV electric range and battery power are included. For each case, …

Integrated Vehicle Thermal Management For Advanced Vehicle Propulsion Technologies: Preprint., K. Bennion, M. Thornton

Publications (T)

A critical element to the success of new propulsion technologies that enable reductions in fuel use is the integration of component thermal management technologies within a viable vehicle package. Vehicle operation requires vehicle thermal management systems capable of balancing the needs of multiple vehicle systems that may require heat for operation, require cooling to reject heat, or require operation within specified temperature ranges. As vehicle propulsion transitions away from a single form of vehicle propulsion based solely on conventional internal combustion engines (ICEs) toward a wider array of choices including more electrically dominant systems such as plug-in hybrid electric vehicles …

Nrel: A Year In Clean Energy Innovations: A Review Of Nrel's Feature Stories, National Renewable Energy Laboratory

Publications (E)

The National Renewable Energy Laboratory (NREL) is the nation’s primary laboratory for renewable energy and energy efficiency research and development.

NREL’s mission and strategy are focused on advancing the U.S. Department of Energy’s and our nation’s energy goals. The laboratory’s scientists and researchers support critical market objectives to accelerate research from scientific innovations to market-viable alternative energy solutions. At the core of this strategic direction are NREL’s research and technology development competencies. These areas span from understanding renewable resources for energy, to the conversion of these resources to renewable electricity and fuels, and ultimately to the use of renewable electricity …

On The Effect Of Hydrodynamic Slip On The Polarization Of A Nonconducting Spherical Particle In An Alternating Electric Field, Hui Zhao

Mechanical Engineering Faculty Research

The polarization of a charged, dielectric, spherical particle with a hydrodynamically slipping surface under the influence of a uniform alternating electric field is studied by solving the standard model (the Poisson–Nernst–Planck equations). The dipole moment characterizing the strength of the polarization is computed as a function of the double layer thickness, the electric field frequency, the particle’s surface charge, and the slip length. Our studies reveal that two processes contribute to the dipole moment: ion transport inside the double layer driven by the electric field and the particle’s electrophoretic motion. The hydrodynamic slip will simultaneously impact both processes. In the …

Electro-Osmotic Flow Over A Charged Superhydrophobic Surface, Hui Zhao

Mechanical Engineering Faculty Research

Bubbles can be trapped inside textured structures such as grooves, forming a superhydrophobic surface. A superhydrophobic surface has a large effective hydrodynamic slip length compared to a smooth hydrophobic surface and holds the promise of enhancing electrokinetic flows that find many interesting applications in microfluidics. However, recent theoretical studies suggested that electro-osmotic flows over a weakly charged superhydrophobic surface

the zeta potential of the surface is smaller than the thermal potential (25 mV) can only be enhanced when liquid-gas interfaces are charged [T. M. Squires, Phys. Fluids 20, 092105 (2008); Bahga et al., J. Fluid Mech. 644, 245 (2010)]. So …