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Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James 2019 Utah State University

Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James

All Graduate Theses and Dissertations

Expanders allow pressurized fluids to undergo a pressure decrease in a controlled environment via volumetric growth to extract fluid energy. There are many types of expanders, and the objective of this thesis is to model the efficiencies of the planetary rotor expander (PRE), a century-old design undeveloped due to insufficient manufacturing capabilities (until recently). Geometric relationships are derived and mathematical models are generated to determine the efficiency of the PRE as a function of design variables. Two industrially relevant case studies show that, to maximize isentropic efficiency, the planetary rotor expander (PRE) rotational frequency is maximized and rotor geometry optimized.


Calibration Of Hot-Film X-Probes For High Accuracy Angle Alignment In Wind Tunnels, Dallin L. Jackson 2019 Utah State University

Calibration Of Hot-Film X-Probes For High Accuracy Angle Alignment In Wind Tunnels, Dallin L. Jackson

All Graduate Theses and Dissertations

This thesis investigates the use of hot-film thermal anemometers to align a plate on a wind tunnel at Hill Air Force Base that is used to calibrate Angle of Attack Transmitters on F-16s. A reoccuring problem with this wind tunnel is that no two instruments can verify an angle reading of the the mounting plate for the Angle of Attack Transmitters to the air stream in the wind tunnel. Multiple thermal anemometer calibration methods, such as Jorgensen’s equation and a look-up table are implemented to attemp to achieve consistent measurements between multiple probes. The results show that it is ...


Fracture Toughness Improvement Of 𝐀𝐥𝟐𝐎𝟑 Ceramics By Grain Size Control And Ductile Phase Reinforcement, Kesong Wang 2019 Washington University in St. Louis

Fracture Toughness Improvement Of 𝐀𝐥𝟐𝐎𝟑 Ceramics By Grain Size Control And Ductile Phase Reinforcement, Kesong Wang

Engineering and Applied Science Theses & Dissertations

This study used grain size control and ductile phase reinforcement to improve fracture toughness of 𝐀𝐥𝟐𝐎𝟑 ceramics. Alpha alumina particles of 100 nm, 0.5-1 micrometers, and 10 micrometers were coated with 1-5 nm nickel by electroless nickel plating (ENP). The coated powders were consolidated at 1200℃-1500℃ by spark plasma sintering (SPS). The sintered samples were annealed at 1100 oC for 1.5 hours and 10 hours to determine the effect of post sintering annealing on hardness and fracture toughness. Density of the samples were measured by the standard Archimedes method using a 5 mL pycnometer. Hardness values were ...


Using Complex Orthogonal Decomposition To Extract Dispersion Relationships For Mass Chain, Nicholas A. Valente, Rickey A. Caldwell 2019 Merrimack College

Using Complex Orthogonal Decomposition To Extract Dispersion Relationships For Mass Chain, Nicholas A. Valente, Rickey A. Caldwell

Across the Bridge: The Merrimack Undergraduate Research Journal

Complex orthogonal decomposition (COD) was used to determine the extracted dispersion relationship of a traveling wave in a mass chain. When COD extracts a wavenumber it will produce M values for each wavenumber, γi, and N values for each frequency, ωi; where M is the number of masses and N is the number of time samples. In this work, least squares and a simple mean of the M-γi’s and N-ωi’s extracted values were used to determine each γi and ωi, respectively. An analytical dispersion relationship for the mass-chain is derived in addition to an approximate dispersion relationship. The ...


Modeling And Computation Of The Maximum Braking Energy Speed For Transport Category Airplanes, Nihad E. Daidzic 2019 AAR Aerospace Consulting, LLC

Modeling And Computation Of The Maximum Braking Energy Speed For Transport Category Airplanes, Nihad E. Daidzic

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

Transport-category or FAR/CS 25 certified airplanes may occasionally become braking energy capacity limited. Such limitation may exist when heavy airplanes are departing airports at high-density altitudes, on relatively long runways, and/or possibly with some tailwind component. A maximum braking energy VMBE speed exists which may limit the maximum allowable takeoff decision/action speed V1. The ever-existing possibility of high-speed rejected takeoff in such conditions may also limit the airplane gross weight for declared available distances. To gain deeper insights and acquire better understanding of the topic, a theoretical model of the maximum braking energy and the related VMBE ...


Determination Of Rejected Landing Roll Runway Point-Of-No-Return And Go-Around In Transport Category Airplanes, Nihad E. Daidzic, Ph.D., Sc.D. 2019 AAR Aerospace Consulting, LLC

Determination Of Rejected Landing Roll Runway Point-Of-No-Return And Go-Around In Transport Category Airplanes, Nihad E. Daidzic, Ph.D., Sc.D.

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

The decelerate-accelerate-takeoff maneuver in transport category airplanes has been discussed. Mathematical model based on total energy conservation has been used to calculate the rejected landing point-of-no-return on a runway which will still enable the airplane to safely execute go-around and achieve regulatory screen heights and takeoff safety speeds. After this point has been exceeded or below the point-of-no-return speed no go-around should ever be considered. Landing long and fast and/or decelerating on slippery runways may very well result in an overrun which could be prevented if the go-around is attempted before reaching this critical runway point. The point-of-no-return on ...


A Contribution Toward Better Understanding Of Overbanking Tendency In Fixed-Wing Aircraft, Nihad E. Daidzic 2019 AAR Aerospace Consulting, LLC

A Contribution Toward Better Understanding Of Overbanking Tendency In Fixed-Wing Aircraft, Nihad E. Daidzic

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

The phenomenon of overbanking tendency for a rigid-body, fixed-wing aircraft is investigated. Overbanking tendency is defined as a spontaneous, unbalanced rolling moment that keeps increasing an airplane’s bank angle in steep turns and must be arrested by opposite aileron action. As stated by the Federal Aviation Administration, the overbanking tendency may lead to a loss of control, especially in instrument meteorological conditions. It was found in this study that the speed differential over wing halves in horizontal turns indeed creates a rolling moment that achieves maximum values for bank angles between 45 and 55 degrees. However, this induced rolling ...


Thermal And Orbital Analysis Of Darkness Cubesat, Katie Dickey 2019 Olivet Nazarene University

Thermal And Orbital Analysis Of Darkness Cubesat, Katie Dickey

Honors Program Projects

Fermi National Accelerator Laboratory is sending a 3U CubeSat into LEO to search for a 3.5 keV photon corresponding to the decay of a theorized dark matter particle called the sterile neutrino. The CubeSat will encounter environmental variations while in orbit that can be computed through an orbital analysis using System’s Tool Kit. In order to minimize thermal noise readout, improve optical resolution, and increase bandwidth, the sensors must be kept below 170K while taking data. This temperature is difficult to achieve due to radiation from the Sun and the Earth’s albedo radiation. Through the thermal analysis ...


Performance Analysis Of An Exhaust Heat Recovery System Utilizing Heat Pipes, Metal Foam, And Thermoelectric Generators, Michael Resciniti 2019 Olivet Nazarene University

Performance Analysis Of An Exhaust Heat Recovery System Utilizing Heat Pipes, Metal Foam, And Thermoelectric Generators, Michael Resciniti

Honors Program Projects

Developing efficient thermoelectric generator systems to recover wasted thermal energy from automotive exhaust gasses has potential to improve engine efficiency and reduce carbon emissions. Due to their high thermal transfer efficiency, heat pipes have been used to assist thermoelectric generator systems in these applications. To aid in additional heat transfer, metal fins are often used with heat pipes to take advantage of extended-surface heat transfer. This paper proposes a thermoelectric generator system that employs metal foam as an extended-surface heat transfer aid used in conjunction with heat pipes. Three test conditions were simulated to evaluate the system performance in terms ...


High Resolution Validation Of Next Generation Turbulent Flow Models Using Neutron Beams, Laser Fluorescence, And Cryogenic Helium, Landen G Mcdonald 2019 University of Tennessee, Knoxville

High Resolution Validation Of Next Generation Turbulent Flow Models Using Neutron Beams, Laser Fluorescence, And Cryogenic Helium, Landen G Mcdonald

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Turbulent fluid flow is an incredibly unpredictable subject that continues to confound scientists and engineers. All of the empirical data that has been the basis of conventional turbulent computational fluid dynamics (CFD) models for decades only extends to roughly the equivalent turbulence created when Michael Phelps swims in a pool. The problem is that this data is then extrapolated out many orders of magnitude in order to design cruise ships, airplanes, and rockets which operate in significantly more turbulent flow regimes. This creates an incredible degree of uncertainty in the design process that demands over-engineering and increased expenditures.

The development ...


Efficient Solar-To-Thermal Energy Conversion And Storage With High-Thermal-Conductivity And Form-Stabilized Phase Change Composite Based On Wood-Derived Scaffolds, Bolin Chen, Meng Han, Bowei Zhang, Gaoyuan Ouyang, Behrouz Shafei, Xinwei Wang, Shan Hu 2019 Iowa State University

Efficient Solar-To-Thermal Energy Conversion And Storage With High-Thermal-Conductivity And Form-Stabilized Phase Change Composite Based On Wood-Derived Scaffolds, Bolin Chen, Meng Han, Bowei Zhang, Gaoyuan Ouyang, Behrouz Shafei, Xinwei Wang, Shan Hu

Shan Hu

Solar-to-thermal energy conversion is one of the most efficient ways to harvest solar energy. In this study, a novel phase change composite with porous carbon monolith derived from natural wood is fabricated to harvest solar irradiation and store it as thermal energy. Organic phase change material n-octadecane is physically adsorbed inside the porous structure of the carbonized wood, and a thin graphite coating encapsulates the exterior of the wood structure to further prevent n-octadecane leakage. The carbonized wood scaffold and the graphite coating not only stabilize the form of the n-octadecane during phase change, but also enhance its thermal conductivity ...


Development Of A One-Equation Turbulence Model Based On K-Ε Closure And Its Extension For Computing Transitional Flows By Including An Intermittency Transport Equation, CHENG PENG 2019 Washington University in St. Louis

Development Of A One-Equation Turbulence Model Based On K-Ε Closure And Its Extension For Computing Transitional Flows By Including An Intermittency Transport Equation, Cheng Peng

Engineering and Applied Science Theses & Dissertations

No abstract provided.


The Effect Of Soil Saturation On The Heat Transfer Rate In A Controlled Environment For Application To Ground Source Heat Pumps, William Barnard 2019 University of Tennessee at Chattanooga

The Effect Of Soil Saturation On The Heat Transfer Rate In A Controlled Environment For Application To Ground Source Heat Pumps, William Barnard

Honors Theses

With the worldwide push for environmentally friendly technology, the topic of geothermal systems has only become more important. Ground Source Heat Pumps (GSHPs) are heat pumps that take advantage of the natural temperature difference between the soil and the air to decrease the amount of power necessary to heat an area. A GSHP has been shown to be capable of increasing efficiency by 3 or 4 times the amount of a conventional heating and cooling system [4]. To take advantage of the full capabilities of a GSHP, one needs to understand what factors can increase or decrease efficiency. While research ...


Computational Simulation Of The Paw-04 Nozzle Configuration, Juan Hernandez 2019 University of Tennessee at Chattanooga

Computational Simulation Of The Paw-04 Nozzle Configuration, Juan Hernandez

Honors Theses

The research was based on the 4th Propulsion Aerodynamics Workshop which was organized by the American Institute of Aeronautics and Astronautics (AIAA) Air Breathing Propulsion System Integration Technical Committee and its objective was to assess the accuracy and numerical prediction capabilities of Computational Fluid Dynamics (CFD). It focused on the work of Behrouzi and McGuirk where they tested two different nozzle configurations under set boundary conditions. The nozzle configurations included a high aspect ratio rectangular nozzle with a clean exit and the same nozzle with an aft-deck attached to the exit. Three different unstructured grids were generated for the clean ...


Analysis And Proposed Improvement Of Hamilton County Vw Elab Equipment, Hiroshi Yanagida 2019 University of Tennessee at Chattanooga

Analysis And Proposed Improvement Of Hamilton County Vw Elab Equipment, Hiroshi Yanagida

Honors Theses

Digital fabrication laboratories have revolutionized project based learning within K-12 STEAM education curriculum. However, classroom utilization of the labs often requires excessive machine hours to accomplish, and this often leads to rapid machine depreciation and disrepair. Many educators do not have the time to repair their equipment while developing curriculum and engaging with their students. This study focuses on building a repair history for common digital fabrication equipment, which includes Prusa i3 Mk2S FDM 3D printers, laser cutters, and CNC routers. Data were collected over a 6 month period to find which machines encountered the most issues. The 3D printers ...


The Analysis Of Erlanger Hospital’S Suture Inventory Management Operations, Amanda George 2019 University of Tennessee at Chattanooga

The Analysis Of Erlanger Hospital’S Suture Inventory Management Operations, Amanda George

Honors Theses

This paper evaluates the impact of using mechanical engineering and operations management principles to an inventory management system in Erlanger Hospital. Erlanger Hospital is a local, nonprofit hospital system in Chattanooga. Erlanger serves as a tertiary referral hospital and a Level I Trauma Center in the region. Therefore, they are heavily depended on during times of crisis or emergency [2]. This study focuses specifically on reducing the loss and ultimate waste of sutures across Erlanger’s surgery wing. A criteria for the appraisal of using mechanical and manufacturing engineering to improve the current system is established based on existing data ...


Solar Tracking Using A Parallel Manipulator Mechanism To Achieve Two-Axis Position Tracking, Joseph Otto Hubach 2019 Rose-Hulman Institute of Technology

Solar Tracking Using A Parallel Manipulator Mechanism To Achieve Two-Axis Position Tracking, Joseph Otto Hubach

Graduate Theses - Mechanical Engineering

A novel solar tracker is presented that uses a parallel manipulator for the tracking mechanism instead of a traditional serial manipulator. The motivation is to create a solar tracker that displays the advantages of two-axis tracking systems (e.g., increased exposure to incident radiation, and enabling the use of efficient concentrating solar cells) while addressing some of the disadvantages of current two-axis tracking systems (e.g., the difficulties associated with having actuators mounted to moving elements within the mechanism). The mobility of the proposed parallel manipulator is examined using Grübler’s Criterion to establish that the manipulator displays the required ...


Predicting The Mechanical Properties Of Nanocomposites Reinforced With 1-D, 2-D And 3-D Nanomaterials, Scott Edward Muller 2019 University of Arkansas, Fayetteville

Predicting The Mechanical Properties Of Nanocomposites Reinforced With 1-D, 2-D And 3-D Nanomaterials, Scott Edward Muller

Theses and Dissertations

Materials with features at the nanoscale can provide unique mechanical properties and increased functionality when included as part of a nanocomposite. This dissertation utilizes computational methods at multiple scales, including molecular dynamics (MD) and density functional theory (DFT), and the coupled atomistic and discrete dislocation multiscale method (CADD), to predict the mechanical properties of nanocomposites possessing nanomaterials that are either 1-D (carbyne chains), 2-D (graphene sheets), or 3-D (Al/amorphous-Si core-shell nanorod).

The MD method is used to model Ni-graphene nanocomposites. The strength of a Ni-graphene nanocomposite is found to improve by increasing the gap between the graphene sheet and ...


Torch Mounted Wire Nipper, Steven D. Patrick, Matt Montgomery, Ben Rouse, Garrett D. Foust 2019 University of Tennessee, Knoxville

Torch Mounted Wire Nipper, Steven D. Patrick, Matt Montgomery, Ben Rouse, Garrett D. Foust

Chancellor’s Honors Program Projects

No abstract provided.


Final Design Report For The Bioburden Pre-Cleaning Device And Dr. Mark Rasnake At The University Of Tennessee Medical Center, Katherine Elizabeth Stiles, Megan Pitz, Kayla Franklin, Simran Dayal, Austin Bullock 2019 University of Tennessee

Final Design Report For The Bioburden Pre-Cleaning Device And Dr. Mark Rasnake At The University Of Tennessee Medical Center, Katherine Elizabeth Stiles, Megan Pitz, Kayla Franklin, Simran Dayal, Austin Bullock

Chancellor’s Honors Program Projects

No abstract provided.


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