Mechanical Engineering Commons^™

In Situ Method Of Measuring Atmosphere Neutral Winds With A Rigid Falling Sphere, Joshua F. Martineau

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The new falling sphere instruments will measure lower E-region winds and density, which are critical for many of the electrodynamics and plasma physics studies that are carried out as part of the NASA suborbital rocket program. The new falling sphere design will take advantage of modern commercially available electronic components and materials. Of primary importance, it is proposed to fly an in-situ instrument that targets the measurement of neutral wind profiles over the altitude range from 80 to 150 km, with accuracy better than that achieved in previous implementations of the falling sphere technique and those typically obtained with the …

A Validation And Comparison About Vabs-Ide And Vabs-Gui, Teng Hu

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Variational Asymptotic Beam Section (VABS) analysis is a computer code for design and analysis of slender structure such as rotor blades, wind turbine blades, missiles, and rockets more efficiently than a full three-dimensional finite element analysis. VABS enables a rigorously a dimensional reduction of the original three-dimensional nonlinear analysis into a one-dimensional nonlinear beam analysis and a two-dimensional linear cross-sectional analysis. The VABS code has been extensively used in academia and industry for comput- ing the sectional properties and recovering three-dimensional fields of composite slender structures. Recently two graphic user interface, namely VABS-IDE and VABS-GUI, have been developed to automatic …

Using Stereo Particle Image Velocimetry To Quantify And Optimize Mixing In An Algae Raceway Using Delta Wings, Blake W. Lance

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Biofuel research has been continually growing over the past six decades. Of the potential sources for biofuels, microalgae is the most promising, and circulating (raceway) ponds are the most cost-effective method for growing microalgae in abundance. Nevertheless, biofuel production from algae must be more efficient to be competitive with traditional fuels. Previous studies using several airfoils, triangles, and squares at high angles to the flow direction (angle of attack) show an increase in mixing in raceways and can improve productivity by up to a factor of 2.2. Researchers show that increasing growth by increasing mixing is a repeatable effect that …

Simulation Of Counterintuitive Pressure Drop In A Parallel Flow Design For A Specimen Basket For Use In The Advanced Test Reactor, Adam X. Zabriskie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To continue improving nuclear energy, new materials must be tested in testing reactors such as the Advanced Test Reactor (ATR) at Idaho National Laboratory. A new test cap section allowed coolant to contact specimens tested in the ATR. A parallel channel test cap section should reduce the pressure drop across this section compared to a single channel. A fluid experiment conducted by Idaho State University showed the pressure drop was actually greater. A Computation Fluid Dynamics simulation using STAR-CCM+ was conducted of the fluid experiment to explain the abnormal pressure drop. The simulation provided evidence of ow through the test …

Computational Fluid Dynamics Analysis Of Butterfly Valve Performance Factors, Adam Del Toro

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Butterfly valves are commonly used to control fluid flow inside of piping systems. A butterfly valve typically consists of a metal disc formed around a central shaft, which acts as its axis of rotation. As a butterfly valve is rotated open, fluid is able to more readily flow past the valve. A butterfly valve’s design is important to understand and is commonly characterized by its own performance factors. How a butterfly valve will perform, while in operation at different opening angles and under different types of flow, is critical information for individuals planning and installing piping systems involving the valve. …

Bubble Coalescence And Breakup Modeling For Computing Mass Transfer Coefficient, Ryan A. Mawson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Modeling fluid behavior with computer numerical models can be very difficult due to the physical phenomenon which can be present in complex fluid systems. One difficult situation to model is when there is more than one type of fluid in a system. Some of these systems include fluids which do not mix, such as is the case when a liquid and a gas are present. In this situation, the gas phase will form bubbles which are dispersed throughout the liquid phase. Modeling the breakup and coalescence of these bubbles is critical to correctly model this type of situation.

There exist …

Effective Thermal Conductivity Of Tri-Isotropic (Triso) Fuel Compacts, Charles P. Folsom

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Next Generation Nuclear Plant (NGNP) program objective is to develop a new type of nuclear reactor that produces process heat instead of electricity. The process heat can be used in the production of hydrogen and many other industrial processes. As part of the NGNP program a new type of nuclear fuel is being developed. The fuel is a composite construction of specially coated fuel particles and graphite pressed together in a cylindrical compact.

Thermal conductivity is an important thermophysical property of the fuel that needs to be measured. Knowledge of the thermal conductivity of the fuel will provide accurate …

Evaluation Of Turbulence Variable Distributions For Incompressible Fully Rough Pipe Flows, Emilie B. Fowler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The specific turbulent kinetic energy, root-mean-square fluctuating vorticity, and mean-vortexwavelength distributions are presented for fully rough pipe flow. The distributions of these turbulence variables are obtained from a proposed turbulence model. Many of the turbulence models commonly used for computational fluid dynamics are based on an analogy between molecular and turbulent transport. However, traditional k-ε and k-ω models fail to exhibit proper dependence on the molecular viscosity. Based on a rigorous application of the Boussinesq’s hypothesis, Phillips proposed a vorticity-based transport equation for the turbulent kinetic energy. The foundation for this vorticity-based transport equation is presented. In future development of …

Autocorrelation-Based Estimate Of Particle Image Density In Particle Image Velocimetry, Scott O. Warner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In Particle Image Velocimetry (PIV), the number of particle images per interrogation region, or particle image density, impacts the strength of the correlation and, as a result, the number of valid vectors and the measurement uncertainty. Therefore, any a-priori estimate of the accuracy and uncertainty of PIV requires knowledge of the particle image density. An autocorrelation-based method for estimating the local, instantaneous, particle image density is presented. Synthetic images were used to develop an empirical relationship based on how the autocorrelation peak magnitude varies with particle image density, particle image diameter, illumination intensity, interrogation region size, and background noise.

This …

Water Main Break Rates In The Usa And Canada: A Comprehensive Study, April 2012, Steven Folkman

Mechanical and Aerospace Engineering Faculty Publications

Modern societies base their economic prosperity on a standard of living which includes a complex network of infrastructure, both above and below ground. Quality drinking water brought to the tap through elaborate underground distribution systems is a critical component to our public health and economic well-being. In the USA and Canada, it has been the hallmark of our industry and cooperation.

EVIDENCE OF DECLINE

Our water infrastructure is now in decline after decades of service. The signs of distress surface daily as water mains break, creating floods and sink holes. The loss of water service is more than an inconvenience, …

Geographical Assessment Of Microalgae Biofuels Potential Incorporating Resource Availability, Jason C. Quinn, Kimberly Catton, Sara Johnson, Thomas H. Bradley

Mechanical and Aerospace Engineering Faculty Publications

Previous assessments of the economic feasibility and large-scale productivity of microalgae biofuels have not considered the impacts of land and carbon dioxide (CO2) availability on the scalability of microalgae-based biofuels production. To accurately assess the near-term productivity potential of large-scale microalgae biofuel in the US, a geographically realized growth model was used to simulate microalgae lipid yields based on meteorological data. The resulting lipid productivity potential of Nannochloropsis under large-scale cultivation is combined with land and CO2 resource availability illustrating current geographically feasible production sites and corresponding productivity in the US. Baseline results show that CO2 transport constraints will limit …

Spatially Localized Measurement Of Thermal Conductivity Using A Hybrid Photothermal Technique, Zilong Hua, Heng Ban, Marat Khafizov, Robert Schley, Rory Kennedy, David H. Hurley

Mechanical and Aerospace Engineering Faculty Publications

A photothermal technique capable of measuring thermal conductivity with micrometer lateral resolution is presented. This technique involves measuring separately the thermal diffusivity, D, and thermal effusivity, e, to extract the thermal conductivity, k = (e²/D)^1/2. To generalize this approach, sensitivity analysis is conducted for materials having a range of thermal conductivities. Application to nuclear fuel is consider by performing experimental validation using two materials (CaF₂ and SiO₂) having thermal properties representative of fresh and high burnup nuclear fuel. The measured conductivities compare favorably with literature values.

Parametric Study Of The Frequency-Domain Thermoreflectance Technique, C. Xing, C. Jensen, Z. Hua, Heng Ban, D. H. Hurley, M. Khafizov, J. R. Kennedy

Mechanical and Aerospace Engineering Faculty Publications

Without requiring regression for parameter determination, one-dimensional (1D) analytical models are used by many research groups to extract the thermal properties in frequency-domain thermoreflectance measurements. Experimentally, this approach involves heating the sample with a pump laser and probing the temperature response with spatially coincident probe laser. Micron order lateral resolution can be obtained by tightly focusing the pump and probe lasers. However, small laser beam spot sizes necessarily bring into question the assumptions associated with 1D analytical models. In this study, we analyzed the applicability of 1D analytical models by comparing to 2D analytical and fully numerical models. Specifically, we …

Frequency Response Of A Gas-Filled Tube With Minor Losses, Brian M. West

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A thesis on the study of the frequency response of a pneumatic system designed to provide pulsed flow for flow control applications is presented. The system consists of a high pressure air source, a high-frequency solenoid valve, a length of tube and a minor loss. The experiment mimics the pneumatic drive for our Coanda-Assisted Spray Manipulation actuator and applies to many flow control applications involving pulsed flow. Square wave signals of various frequency are fed to the solenoid valve. The flow at the exit of the system is measured with a single hot wire and compared to steady flow through …

Reduced Gravity Landing Research Vehicle Design, Sarah Isert

Undergraduate Honors Capstone Projects

Human and robotic missions beyond low earth orbit (LEO) are key components of NASA's currently emerging strategy for space exploration. These missions will inevitably include humancrewed lunar and planetary surface landings. Trips to near-earth asteroids are also in the incipient planning stages. A permanent presence on the surface of an extra terrestrial body like Mars or the Moon will require many landings by both human-crewed and robotic spacecraft.

Planetary and lunar surface landings are inherently dangerous undertakings, and successful landings are indeed rare events. Since the end of the Apollo era with the completion of the Apollo 17 mission in …

Asymptotic Multiphysics Modeling Of Composite Beams, Qi Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of composite beam models are constructed for efficient high-fidelity beam analysis based on the variational-asymptotic method (VAM). Without invoking any a priori kinematic assumptions, the original three-dimensional, geometrically nonlinear beam problem is rigorously split into a two-dimensional cross-sectional analysis and a one-dimensional global beam analysis, taking advantage of the geometric small parameter that is an inherent property of the structure.

The thermal problem of composite beams is studied first. According to the quasisteady theory of thermoelasticity, two beam models are proposed: one for heat conduction analysis and the other for thermoelastic analysis. For heat conduction analysis, two different …

Axisymmetric Finite Element Modeling Of Adhesive Joint Between A Laminated Composite And Metal Cylinder, Casey A. Talbot

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Because lowering weight as much as possible is desirable in all applications designed to go to space, the use of composite materials is desirable. Composites are materials that are made up of two or more separate materials usually with significantly different characteristics which remain separate and distinct in their completed state. Fiber-reinforced epoxy composites, in general, are very strong and light. Because most space structures cannot solely be made of composites, a method to join them with metals is needed. Adhesive joining, or gluing, has been determined to be the most promising option.

For the joining technique to be used, …

Evaluation Of An Incompressible Energy-Vorticity Turbulence Model For Fully Rough Pipe Flow, Doug F. Hunsaker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Traditional methods of closing the Boussinesq-based Reynolds-averaged Navier-Stokes equations are considered, and suggestions for improving two-equation turbulence models are made. The traditional smooth-wall boundary conditions are shown to be incorrect, and the correct boundary conditions are provided along with sample solutions to traditional models. The correct boundary condition at a smooth wall for dissipation-based turbulence models is that which forces both the turbulent kinetic energy and its first derivative to zero. Foundations for an energy-vorticity model suggested by Phillips are presented along with the near-smooth-wall behavior of the model. These results show that at a perfectly smooth wall, the turbulent …

Optimization Of A Low Reynold's Number 2-D Inflatable Airfoil Section, Todd A. Johansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A stand-alone genetic algorithm (GA) and an surrogate-based optimization (SBO) combined with a GA were compared for accuracy and performance. Comparisons took place using the Ackley Function and Rastrigin's Function, two functions with multiple local maxima and minima that could cause problems for more traditional optimization methods, such as a gradient-based method. The GA and SBO with GA were applied to the functions through a fortran interface and it was found that the SBO could use the same number of function evaluations as the GA and achieve at least 5 orders of magnitude greater accuracy through the use of surrogate …

Low-Thrust Assisted Angles-Only Navigation, Robert W. Gillis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tradition spacecraft proximity operations require large and expensive on-board sensors and significant ground support. Relative angle measurements can be obtained from small, simple, and inexpensive on-board sensors, but have not traditionally been used for proximity operation because of difficulty generating rang information. In this thesis it is shown that useful relative range data can be generated provided that the spacecraft is experiencing a small continuous thrust such as would be provided by a low-thrust propulsion system. In previous work range observability was shown with impulsive maneuvers. This thesis will expand this work to low-thrust spacecraft and will show how range …

Experimental Testing Of The Accuracy Of Attitude Determination Solutions For A Spin-Stabilized Spacecraft, Keegan P. Ryan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spin-stabilized spacecraft generally rely on sun and three-axis magnetic field sensor measurements for attitude determination. This study experimentally determines the total accuracy of attitude determination solutions using modest quality sensors. This was ac- complished by having a test spacecraft collect data during spinning motions. The data was then post-processed to find the attitude estimates, which were then compared to the experimentally measured attitude. This same approach will be used to test the accuracy of the attitude determination system of the DICE spacecraft to be built by SDL/USU.

A Thermomechanical Analysis Of An Ultrasonic Bonding Mechanism, Chunbo Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A systematic experimental and numerical combined study of the thermomechanical bonding mechanisms in the ultrasonic welding (UW) process was conducted. A fully coupled thermomechanical finite element model has been built to fully understand the evolution and coupling between the in-process thermomechanical variables. The severe, localized, plastic deformation at the bond region is believed to be the major phenomenon for bond formation in ultrasonic welding. The influences of substrate dimensions on bond formation were studied and explained with an analytical vibration model. The formation of banded and cyclic stress-strain maxima in the substrate was found to be caused by superposition of …

Dislocation Density-Based Finite Element Method Modeling Of Ultrasonic Consolidation, Deepankar Pal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A dislocation density-based constitutive model has been developed and implemented into a crystal plasticity quasi-static finite element framework. This approach captures the statistical evolution of dislocation structures and grain fragmentation at the bonding interface when sufficient boundary conditions pertaining to the Ultrasonic Consolidation (UC) process are prescribed.

The hardening is incorporated using statistically stored and geometrically necessary dislocation densities (SSDs and GNDs), which are dislocation analogs of isotropic and kinematic hardening, respectively. Since the macroscopic global boundary conditions during UC involves cyclic sinosuidal simple shear loading along with constant normal pressure, the cross slip mechanism has been included in the …

Discharge Coefficients Of Oblique Weirs, Samuel Egnew Tingey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Oblique weirs are those weirs placed at an angle with respect to the channel centerline. They can be used in canal applications where more discharge is needed, but there is limited freeboard. The discharge coefficients were determined for 54 different weirs by measuring total head for various flows over each weir. These weirs included sharp, half round and quarter-round-crested weirs. There were 18 weirs for each crest shape with three weir heights for each angle tested. The oblique angles tested were 10°, 15°, 25°, 45°, 60°, and 90° with respect to the channel centerline, with the nominal weir heights being …

Astro Camp Presentation, Get Away Special Team 2011

Education and Outreach

No abstract provided.

Theoretical Approach For Error Estimation Of Temperature And Thermal Conductivity In Uranium Dioxide Fuel, Adam John Gerth

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The knowledge of in-reactor thermophysical properties of nuclear fuel rods, which are usually composed of uranium dioxide (UO2) ceramics, is important for the safe design and operation of nuclear power plants. A two thermocouple method can be utilized to determine the thermal conductivity within the fuel rods by measuring rod centerline temperature and cladding temperature. Using this technique, Halden Reactor Project (HRP) has developed a correlation for thermal conductivity of UO2 as a function of temperature and burnup. This correlation for thermal conductivity was extracted from experimental data based on a constant thermal conductivity assumption of the fuel rod. However, …

Heat Transfer Through A Rotating Ball Bearing At Low Angular Velocities, Sarah Isert

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Bearings are commonly used in mechanical systems when there are rotating parts in the system. For bearings that run at speeds above about 1000 revolutions per minute, such as those used in aircraft turbines, machining tools, and automotive engines, it is important to take into account the heat transfer through the bearing system due to friction. Heat transfer is generally not considered for applications where the bearing is rotating at low speeds, such as clocks and bicycles. However, for certain aerospace applications, such as precision instruments or wind turbines, the heat transfer through the bearing becomes relevant. The case where …

Characteristics Of Combustion Flame Sprayed Nickel Aluminum Using A Coanda Assisted Spray Manipulation Collar For Off-Normal Deposits, Reid S. Archibald

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A novel flame spray collar called the Coanda Assisted Spray Manipulation collar (CSM) has been tested for use on the Sulzer Metco 5P II combustion flame spray gun. A comparison study of the stock nozzle and the CSM has been performed by evaluating the porosity, surface roughness, microhardness, tensile strength and microscopy of normal and off-normal sprayed NiAl deposits. The use of the CSM collar resulted in the need to position the sprayed coupons closer to the gun, which in turn affected the particle impact energy and particle temperatures of the NiAl powder. For the CSM, porosities had a larger …

Investigation Of The Design And Static Behavior Of Cylindrical Tubular Composite Adhesive Joints Utilizing The Finite Element Method And Stress-Based Failure Theories, Michael D. Lambert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The stress and strength behavior of cylindrical tubular adhesive joints composed of dissimilar materials was explored. This was accomplished with the finite element method (FEM) and stress-based failure theories. Also, it was shown how a design of experiments (DOE) based method can be used to objectively organize the process of optimizing joint strength by using stress-based failure criteria.

The finite element program used in this work was written in-house from scratch to implement the FEM for the purpose of solving both axisymmetric and three-dimensional linear elastic governing equations of static equilibrium. The formulation of the three-dimensional model is presented, and …

Automatic Particle Image Velocimetry Uncertainty Quantification, Benjamin H. Timmins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The uncertainty of any measurement is the interval in which one believes the actual error lies. Particle Image Velocimetry (PIV) measurement error depends on the PIV algorithm used, a wide range of user inputs, flow characteristics, and the experimental setup. Since these factors vary in time and space, they lead to nonuniform error throughout the flow field. As such, a universal PIV uncertainty estimate is not adequate and can be misleading. This is of particular interest when PIV data are used for comparison with computational or experimental data.

A method to estimate the uncertainty due to the PIV calculation of …