Conditions For Barrel And Clam-Shell Liquid Drops To Move On Bio-Inspired Conical Wires,
2017
University of Texas at Arlington
Conditions For Barrel And Clam-Shell Liquid Drops To Move On Bio-Inspired Conical Wires, Cheng Luo, Xiang Wang
Mechanical and Aerospace Faculty Publications - Archive
It has been reported that, in a foggy environment, water drops with either barrel or clam-shell shapes are capable of self-running on conical wire-like structures, such as cactus spines, spider silk, and water striders’ legs. On the other hand, the corresponding moving mechanisms are still not quite understood. For instance, it is unclear under what conditions clam-shell drops would move from the tip towards the root on a conical wire. In this work, based on the balance of forces, we derive conditions for a drop to self-transport towards or away from the root. We find that, although barrel and clam-shell …
The Study On Shanghai International Air Transportation Hub,
2017
World Maritime University
The Study On Shanghai International Air Transportation Hub, Diandian Li
World Maritime University Dissertations
No abstract provided.
Design And Validation Of Pressure Based Flow Rate Soft Sensor For Freeze-Drying,
2017
Purdue University
Design And Validation Of Pressure Based Flow Rate Soft Sensor For Freeze-Drying, Pasita Pibulchinda, Tong Zhu, Vaibhav Kshirsagar, Alina A. Alexeenko
The Summer Undergraduate Research Fellowship (SURF) Symposium
Lyophilization or freeze drying is a process of removing water by sublimation. It is commonly used to extend the shelf life of drugs in the pharmaceutical industry. Because the process is costly and time consuming, precise and efficient pressure, temperature control and drying time estimation are required. It is the goal of freeze-drying to run at maximum capacity while staying within the safe zone by carefully controlling the sublimation rate. Currently, real time estimation of sublimation rate is still challenging. The technique available called Tunable diode laser absorption spectroscopy (TDLAS) is invasive, and requires major modifications. The current study focuses …
Minimum Induced Power For A Helicopter In High-Speed Forward Flight,
2017
Washington University in St. Louis
Minimum Induced Power For A Helicopter In High-Speed Forward Flight, Junsoo (Sean) Hong
McKelvey School of Engineering Graduate Student Theses & Dissertations
A dynamic inflow model is used to calculate minimum induced power for a helicopter in high-speed forward flight with infinite and finite number of blades. Comparisons between analytical and numerical results are shown and they show good agreement. Different flow conditions (such as with and without reverse flow or inflow feedback) are used to show how each condition affects optimum induced power. Several results confirm the findings of earlier investigations such as a singularity in rotor power in reverse flow and induced power reduction with increase in blade number. Some of the new findings are that greater inflow feedback (due …
Satellite Propulsion Spectral Signature Detection And Analysis For Space Situational Awareness Using Small Telescopes,
2017
Air Force Institute of Technology
Satellite Propulsion Spectral Signature Detection And Analysis For Space Situational Awareness Using Small Telescopes, Pamela L. Wheeler
Theses and Dissertations
Safe satellite operations are of utmost importance. Maintaining precise orbital maintenance places stringent performance requirements on current propulsion systems, which are often electric propulsion systems. Electron temperature is a commonly used diagnostic to determine the performance of a Hall thruster, and recent work has correlated near infrared (NIR) spectral measurements of ionization lines of xenon and krypton to electron temperature measurements. In the research herein, appropriate line spectra ratios are identified for each propellant type when used with remote space-to-ground observations. NIR plume emissions were used to characterize a 600 Watt Hall thruster for a variety of observation angles and …
Tu-Pod: A Cube Satellite (Cubesat) And Tube Satellite Dispenser Produced Via 3d Printing, Successful Launch, Orbit And Dispensing Of Two Tube Satellites,
2017
Morehead State University
Tu-Pod: A Cube Satellite (Cubesat) And Tube Satellite Dispenser Produced Via 3d Printing, Successful Launch, Orbit And Dispensing Of Two Tube Satellites, Robert J. Twiggs, Matt Craft, Amin Djamshidpour, Chantal Cappelletti, Ken Biba, Stewart Davis
Robert "Bob" Twiggs STEM Education Collection
A PowerPoint Presentation created by Matt Craft, Amin Djamshidpour, Chantal Cappelletti, Bob Twiggs, Ken Biba, and Stewart Davis titled "TU-POD: A Cube Satellite (CubeSat) and Tube Satellite Dispenser Produced via 3D Printing, Successful Launch, Orbit and Dispensing of Two Tube Satellites" from August 6, 2017.
Using P-Band Signals Of Opportunity Radio Waves For Root Zone Soil Moisture Remote Sensing,
2017
Rose-Hulman Institute of Technology
Using P-Band Signals Of Opportunity Radio Waves For Root Zone Soil Moisture Remote Sensing, Phillip H. Lipinski, Benjamin R. Nold, James L. Garrison
The Summer Undergraduate Research Fellowship (SURF) Symposium
Retrieval of Root Zone Soil Moisture (RZSM) is important for understanding the carbon cycle for use in climate change research as well as meteorology, hydrology, and precision agriculture studies. A current method of remote sensing, GNSS-R uses GPS signals to measure soil moisture content and vegetation biomass, but it is limited to 3-5 cm of soil penetration depth. Signals of Opportunity (SoOp) has emerged as an extension of GNSS-R remote sensing using communication signals. P-band communication signals (370 MHz) will be studied as an improved method of remote sensing of RZSM. P-band offers numerous advantages over GNSS-R, including stronger signal …
Additive Manufacturing Of High Solids Loading Hybrid Rocket Fuel Grains,
2017
Olivet Nazarene University
Additive Manufacturing Of High Solids Loading Hybrid Rocket Fuel Grains, Stephen P. Johnson, Michael Baier, Ibrahim E. Gunduz, Steven F. Son
The Summer Undergraduate Research Fellowship (SURF) Symposium
Hybrid rocket motors offer many of the benefits of both liquid and solid rocket systems. Like liquid engines, hybrid rocket motors are able to be throttled, can be stopped and restarted, and are safer than solid rocket motors since the fuel and oxidizer are in different physical states. Hybrid rocket motors are similar to solid motors in that they are relatively simple and have a high density-specific impulse. One of the major drawbacks of hybrid rocket motors is a slower burning rate than solid rocket motors. Complex port geometries provide greater burning surface area to compensate for lower burning rates …
Using High Resolution Images To Investigate Fatigue Crack Initiation Of Alloys At The Microstructural Level,
2017
Purdue University
Using High Resolution Images To Investigate Fatigue Crack Initiation Of Alloys At The Microstructural Level, Michael P. Reinhold, Alberto Mello, Michael Sangid
The Summer Undergraduate Research Fellowship (SURF) Symposium
Microstructural features within a material dictate the material’s mechanical behavior and lead to localized strains as the sample is deformed. In order to further understand structural failure, an improved understanding of how microstructural features influence failure is necessary. Fatigue is one common mode of failure for aerospace applications, and a better understanding of the conditions of crack initiation can provide information that ultimately may increase longevity of aerospace systems. This paper investigates the hypothesis that fatigue crack initiation for a cyclically loaded sample is correlated to areas of higher localized strain. The experiment was conducted using a Ti-6Al-4V sample subjected …
Operation Of The T-100 Hall Effect Thruster,
2017
Purdue University
Operation Of The T-100 Hall Effect Thruster, Glynn Smith, Omar Dary, Alexey Shashurin
The Summer Undergraduate Research Fellowship (SURF) Symposium
The introduction of Hall Effect Thrusters from the former Soviet Union to the United States generated considerable interest in using the propulsion system aboard Western spacecraft. The established programs evaluated the SPT-100, and TAL-55 Hall Effect Thrusters for efficiency, lifetime, and performance characteristics. The T-100 model garnered only minor interest during this time compared with the same generation counterparts, the SPT-100, and TAL-55. This gap in knowledge on the efficiency, and performance of the T-100 warrants investigation into the design, and operation of the thruster. Operational characteristics will be measured on a restored T-100 Hall Thruster, using argon as a …
Hazard Assessment Of Meteoroid Impact For The Design Of Lunar Habitats,
2017
Purdue University
Hazard Assessment Of Meteoroid Impact For The Design Of Lunar Habitats, Herta Paola Montoya, Shirley Dyke, Julio A. Ramirez, Antonio Bobet, H. Jay Melosh, Daniel Gomez
The Summer Undergraduate Research Fellowship (SURF) Symposium
The design of self-sustaining lunar habitats is a challenge primarily due to the Moon’s lack of atmospheric protection and hazardous environment. To assure safe habitats that will lead to further lunar and space exploration, it is necessary to assess the different hazards faced on the Moon such as meteoroid impacts, extreme temperatures, and radiation. In particular, meteoroids pose a risk to lunar structures due to their high frequency of occurrence and hypervelocity impact. Continuous meteoroid impacts can harm structural elements and vital equipment compromising the well-being of lunar inhabitants. This study is focused on the hazard conceptualization and quantification of …
Using Unmanned Aerial Vehicles (‘Drones’) To Collect Data From Tagged Fishers In The Environment,
2017
California State University, Sacramento
Using Unmanned Aerial Vehicles (‘Drones’) To Collect Data From Tagged Fishers In The Environment, Vu A. Pham, Marc Horney, Aaron Drake
STAR Program Research Presentations
Fisher (Pekania pennant) belongs to the weasel family. In October 2014, the United States Fish and Wildlife Service proposed to list the West Coast Distinct Population Segment of fisher as threatened under the Endangered Species Act. We wish to better define where fishers live within their habitats and use that information to improve conservation efforts. Previously, to track the behavior of wild fishers, researchers put tracker collars on the animals and relied on networks of fixed antennas on the ground in the environment to collect data. We are experimenting with using unmanned aerial vehicles (‘drones’) to collect data …
Advanced Methods Of Nondestructive Inspection Of Composite Structures Based On Limited Angle X-Ray Computed Tomography,
2017
University of Texas at Arlington
Advanced Methods Of Nondestructive Inspection Of Composite Structures Based On Limited Angle X-Ray Computed Tomography, Ekaterina Bostaph
Mechanical and Aerospace Engineering Dissertations - Archive
This research aimed to study the potential for breaking through object size limitations of current X-ray computed tomography (CT) systems by implementing a limited angle scanning technique. CT stands out among other industrial nondestructive inspection (NDI) methods due to its unique ability to perform 3D volumetric inspection, unmatched micro-focus resolution, and objectivity that allows for automated result interpretation. This work attempts to advance NDI technique to enable microstructural material characterization and structural diagnostics of composite structures, where object sizes often prohibit the application of full 360o CT. Even in situations where the objects can be accommodated within existing micro-CT configuration, …
Modeling And Measurements Of Thermal Transport In Li-Ion Based Energy Conversion And Storage Devices,
2017
University of Texas at Arlington
Modeling And Measurements Of Thermal Transport In Li-Ion Based Energy Conversion And Storage Devices, Krishna Shah
Mechanical and Aerospace Engineering Dissertations - Archive
Heat transfer is of significant importance in energy conversion and storage devices such as Lithium-ion batteries for its safe operation and performance. Li-ion batteries are considered to be the state of the art among the energy storage devices due to their very high energy density and high power density. However, the safety of Li-ion batteries has become a concern in light of recent incidents, where there have been catastrophic events reported due to overheating of large battery packs. It is imperative to fully understand the nature of thermal transport in Li-ion cells. However, this has not been explored in detail …
Space Access Systems Design: Synthesis Methodology Development For Conceptual Design Of Future Space Access Systems,
2017
University of Texas at Arlington
Space Access Systems Design: Synthesis Methodology Development For Conceptual Design Of Future Space Access Systems, Loveneesh Rana
Mechanical and Aerospace Engineering Dissertations - Archive
The early Conceptual Design (CD) of a Space Access System (SAS) is the most abstract, innovative, and technologically challenging phase throughout the entire aerospace product development life-cycle. While it is the most important life-cycle phase which influences around 80 percent of the overall life-cycle-cost, it is also the least understood design phase. The history of space access vehicle design provides numerous examples of projects that failed due to lack of a proper technology-hardware-mission assessment in the CD phase. The present dissertation addresses this crucial phase and develops a prototype best practice solution process to advance the current state of the …
Micro/Nanoencapsulated Phase Change Materials (Pcms) Toward High Temperature Thermal Energy Storage Applications,
2017
University of Texas at Arlington
Micro/Nanoencapsulated Phase Change Materials (Pcms) Toward High Temperature Thermal Energy Storage Applications, Hanfei Zhang
Mechanical and Aerospace Engineering Dissertations - Archive
Thermal energy is one of the most important renewable energy sources because of its abundancy. However, despite the long history of people practically trying to harvest thermal energy, the efficiency of thermal energy storage and application to daily life utilization is still a major limitation, especially for high temperature (>300oC) applications. Concentrating solar power (CSP) is one of the very few technologies that have been used commercially to produce electricity from solar thermal energy. Benefiting from the extra latent heat stored during melting/freezing, phase change materials (PCMs) with a high melting point are commonly used in these systems functioning …
Field-Directed Fabrication Of Hierarchical Structures Toward Electrochemical Applications,
2017
University of Texas at Arlington
Field-Directed Fabrication Of Hierarchical Structures Toward Electrochemical Applications, Anirudh Balram
Mechanical and Aerospace Engineering Dissertations - Archive
The ubiquity of hierarchical structures in nature indicates an inherent advantage to having morphological features comprised of multiple length scales. Such structures help maximize interfacial surface area, allowing for efficient chemical reactions and mass transport despite volumetric constraints. In electrochemical applications such as batteries, supercapacitors, electrolysis, fuel cells, catalysis etc. there is a similar necessity to maximize electrochemically active surface area to facilitate facile charge and mass transport. Inspired by examples in nature, this work seeks to develop scalable fabrication techniques to obtain hierarchically structured high-performance electrodes for electrochemical applications, with a focus on energy applications. Particular emphasis was laid …
Numerical Investigation Of Stability Characteristics Of A Jet In Counterflow,
2017
University of Texas at Arlington
Numerical Investigation Of Stability Characteristics Of A Jet In Counterflow, Siddarth Chintamani
Mechanical and Aerospace Engineering Dissertations - Archive
A jet in counterflow is a configuration in which a jet is issued into an opposing external stream of fluid. Some of the possible applications of this configuration include study of pollutant discharge into body of water, aerodynamic flame holder in after burner, reduction of drag and cooling of bluff body by ejecting a jet of coolant gas into counterflowing stream, thrust vectoring of supersonic jets, sonic boom mitigation. The instability associated with flow reversal which is observed in this configuration of the jet leads to enhanced mixing. However, a detailed understanding of the dynamics and control is needed to …
Multi-Mesh Reduced-Order Basis Method For Finite Element Analysis,
2017
University of Texas at Arlington
Multi-Mesh Reduced-Order Basis Method For Finite Element Analysis, Ashkan Akbariyeh
Mechanical and Aerospace Engineering Dissertations - Archive
Reduced order modeling of differential equations parametrized over a parameter space can be used to accelerate optimization and parameter estimation problems. The method of snapshots or reduced order basis is well established among researchers as a tool to build reduced order models of ordinary differential equations. The reduced order basis method has been utilized for numerical solution of parametric PDE problems by researchers in recent years and has many advantages over response surface methods. The application of ROB to finite element analysis has been restricted to using a fixed mesh for snapshots. In this work, a new method is developed …
Thermal Measurement And Optimization Of Materials And Processes In A Li-Ion Cell,
2017
University of Texas at Arlington
Thermal Measurement And Optimization Of Materials And Processes In A Li-Ion Cell, Vivek Vishwakarma
Mechanical and Aerospace Engineering Dissertations - Archive
Applications of Lithium-ion cells range from consumer electronics to electric cars because of their excellent electrochemical performance and energy density. However, a Li-ion cell also suffers from poor thermal transport characteristics, which reduces performance, causes overheating and thermal runaway. This work contributes towards thermal characterization of key Li-ion battery materials and identifies and improves the rate-limiting, material-level thermal conduction process in a Li-ion cell. Among the various materials within a Li-ion cell, the separator is expected to have the lowest thermal conductivity. In this work, we have carried out first-ever measurements of thermal conductivity and heat capacity of the separator …
