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Nuclear Thermal Propulsion Reactor Shutdown And Residual Heating, Samantha B. Rawlins 2019 University of Alabama in Huntsville

Nuclear Thermal Propulsion Reactor Shutdown And Residual Heating, Samantha B. Rawlins

Research Horizons Day Posters

No abstract provided.


Development Of A Magnetic Nozzle Model For Puff, Nathan Schilling 2019 University of Alabama in Huntsville

Development Of A Magnetic Nozzle Model For Puff, Nathan Schilling

Research Horizons Day Posters

No abstract provided.


Rotor Wing Interaction Of The Low Reynolds Numbers, Darnisha Crane, Mingtai Chen 2019 University of Alabama in Huntsville

Rotor Wing Interaction Of The Low Reynolds Numbers, Darnisha Crane, Mingtai Chen

Research Horizons Day Posters

No abstract provided.


An Enhanced Fuel Cell Dynamic Model With Electrochemical Phenomena Parameterization As Test Bed For Control System Analysis, Victor M. Fontalvo, George J. Nelson, Humberto A. Gomez, Marco E. Sanjuan 2019 University of Alabama in Huntsville

An Enhanced Fuel Cell Dynamic Model With Electrochemical Phenomena Parameterization As Test Bed For Control System Analysis, Victor M. Fontalvo, George J. Nelson, Humberto A. Gomez, Marco E. Sanjuan

PRC-Affiliated Research

In this work, a model of a proton exchange membrane fuel cell (PEMFC) is presented. A dynamic performance characterization is performed to assess the cell transient response to input variables. The model used in the simulation considers three different phenomena: mass transfer, thermodynamics, and electrochemistry. The main sources of voltage loss are presented: activation, electrical resistance, and concentration. The model is constructed to avoid the use of fitted parameters, reducing the experimentation required for its validation. Hence, the electrochemical model is parameterized by physical variables, including material properties and geometrical characteristics. The model is demonstrated as a test-bed for PEMFC …


An Enhanced Fuel Cell Dynamic Model With Electrochemical Phenomena Parameterization As Test Bed For Control System Analysis, Victor M. Fontalvo, George J. Nelson, Humberto A. Gomez, Marco E. Sanjuan 2019 University of Alabama in Huntsville

An Enhanced Fuel Cell Dynamic Model With Electrochemical Phenomena Parameterization As Test Bed For Control System Analysis, Victor M. Fontalvo, George J. Nelson, Humberto A. Gomez, Marco E. Sanjuan

PRC-Affiliated Research

In this work, a model of a proton exchange membrane fuel cell (PEMFC) is presented. A dynamic performance characterization is performed to assess the cell transient response to input variables. The model used in the simulation considers three different phenomena: mass transfer, thermodynamics, and electrochemistry. The main sources of voltage loss are presented: activation, electrical resistance, and concentration. The model is constructed to avoid the use of fitted parameters, reducing the experimentation required for its validation. Hence, the electrochemical model is parameterized by physical variables, including material properties and geometrical characteristics. The model is demonstrated as a test-bed for PEMFC …


An Enhanced Fuel Cell Dynamic Model With Electrochemical Phenomena Parameterization As Test Bed For Control System Analysis, Victor M. Fontalvo, George J. Nelson, Humberto A. Gomez, Marco E. Sanjuan 2019 University of Alabama in Huntsville

An Enhanced Fuel Cell Dynamic Model With Electrochemical Phenomena Parameterization As Test Bed For Control System Analysis, Victor M. Fontalvo, George J. Nelson, Humberto A. Gomez, Marco E. Sanjuan

PRC-Affiliated Research

In this work, a model of a proton exchange membrane fuel cell (PEMFC) is presented. A dynamic performance characterization is performed to assess the cell transient response to input variables. The model used in the simulation considers three different phenomena: mass transfer, thermodynamics, and electrochemistry. The main sources of voltage loss are presented: activation, electrical resistance, and concentration. The model is constructed to avoid the use of fitted parameters, reducing the experimentation required for its validation. Hence, the electrochemical model is parameterized by physical variables, including material properties and geometrical characteristics. The model is demonstrated as a test-bed for PEMFC …


Incidence Of An Astronaut Not Sealing The Pressure Garment Visor On Reentry, Cameron M. Smith, Trent Tresch 2019 Portland State University

Incidence Of An Astronaut Not Sealing The Pressure Garment Visor On Reentry, Cameron M. Smith, Trent Tresch

Journal of Human Performance in Extreme Environments

Audiovisual records of a Project Mercury pilot’s activities during an orbital flight indicate that his visor was left open during reentry and descent to the sea surface, phases of flight during which cabin pressure loss was to be mitigated by suit pressurization; however, the suit could not have been pressurized with the visor open. Thus, for a presently unknown reason, a critical safety step—sealing the visor and making a pressure suit integrity test before reentry—was overlooked in this flight. Later, Space Shuttle flights were carried out with visors unsealed for much of the launch and landing phases, with the false …


The Potential Science And Engineering Value Of Samples Delivered To Earth By Mars Sample Return, David W. Beaty, Monica M. Grady, Harry Y. McSween, Elliot Sefton-Nash, B. L. Carrier, Francesca Altieri, Yuri Amelin, Eleonora Ammannito, Mahesh Anand, Liane G. Benning, Janice L. Bishop, Lars E. Borg, Dale Boucher, John R. Brucato, Henner Busemann, Kathleen A. Campbell, Andrew D. Czaja, Vinciane Debaille, David J. Des Marais, Michael Dixon, Bethany L. Ehlmann, Jack D. Farmer, David C. Fernandez-Remolar, Justin Filiberto, Jennifer Fogarty, Daniel P. Galvin, Y. S. Goreva, Lydia J. Hallis, Andrea Dawn Harrington, Elisabeth M. Hausrath, Chris D.K. Herd 2019 California Institute of Technology

The Potential Science And Engineering Value Of Samples Delivered To Earth By Mars Sample Return, David W. Beaty, Monica M. Grady, Harry Y. Mcsween, Elliot Sefton-Nash, B. L. Carrier, Francesca Altieri, Yuri Amelin, Eleonora Ammannito, Mahesh Anand, Liane G. Benning, Janice L. Bishop, Lars E. Borg, Dale Boucher, John R. Brucato, Henner Busemann, Kathleen A. Campbell, Andrew D. Czaja, Vinciane Debaille, David J. Des Marais, Michael Dixon, Bethany L. Ehlmann, Jack D. Farmer, David C. Fernandez-Remolar, Justin Filiberto, Jennifer Fogarty, Daniel P. Galvin, Y. S. Goreva, Lydia J. Hallis, Andrea Dawn Harrington, Elisabeth M. Hausrath, Chris D.K. Herd

Geoscience Faculty Research

Executive summary provided in lieu of abstract.


Nasa Mars Greenhouse, Alexa Escalona, Thomas Lee Hodsden III, Zoe Ault Rivas, Grace Genszler, Morgan McGonagle, David Dick, Christopher Yu, Peter Mahoney Jr. 2019 Dartmouth College

Nasa Mars Greenhouse, Alexa Escalona, Thomas Lee Hodsden Iii, Zoe Ault Rivas, Grace Genszler, Morgan Mcgonagle, David Dick, Christopher Yu, Peter Mahoney Jr.

ENGS 89/90 Reports

NASA conducts an annual BIG (Breakthrough, Innovative, Game-Changing) Idea Challenge for university-level students across the country. This ENGS 90 Group competed and was chosen as one of the five finalists with a low-cost, low-risk design of an inflatable greenhouse which can support a human mission to Mars. This greenhouse features a hydroponic growing system to grow eight different food crops to meet the nutritional requirements of a four-person crew.


Sweep And Taper Analysis Of Surfboard Fins Using Computational Fluid Dynamics, Brandon James Baldovin 2019 California Polytechnic State University, San Luis Obispo

Sweep And Taper Analysis Of Surfboard Fins Using Computational Fluid Dynamics, Brandon James Baldovin

Master's Theses

The research presented here provides a basis for understanding the hydrodynamics of surfboard fin geometries. While there have been select studies on fins there has been little correlation to the shape of the fin and its corresponding hydrodynamic performance. This research analyzes how changing the planform shape of a surfboard fin effects its performance and flow field. This was done by isolating the taper and sweep distribution of a baseline geometry and varying each parameter individually whilst maintaining a constant span and surface area. The baseline surfboard fin was used as a template in Matlab to generate a set of …


End-To-End Development Of A High-Altitude Pressure Vessel, Matthew Haskell, Erik Korzon, Elena Pradhan 2019 University of Alabama in Huntsville

End-To-End Development Of A High-Altitude Pressure Vessel, Matthew Haskell, Erik Korzon, Elena Pradhan

Research Horizons Day Posters

No abstract provided.


Assessment Of Turbulence Models In A Hypersonic Cold-Wall Turbulent Boundary Layer, Junji Huang, Jorge-Valentino Bretzke, Lian Duan 2019 Missouri University of Science and Technology

Assessment Of Turbulence Models In A Hypersonic Cold-Wall Turbulent Boundary Layer, Junji Huang, Jorge-Valentino Bretzke, Lian Duan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this study, the ability of standard one- or two-equation turbulence models to predict mean and turbulence profiles, the Reynolds stress, and the turbulent heat flux in hypersonic cold-wall boundary-layer applications is investigated. The turbulence models under investigation include the one-equation model of Spalart-Allmaras, the baseline k-ω model by Menter, as well as the shear-stress transport k-ω model by Menter. Reynolds-Averaged Navier-Stokes (RANS) simulations with the different turbulence models are conducted for a flat-plate, zero-pressure-gradient turbulent boundary layer with a nominal free-stream Mach number of 8 and wall-to-recovery temperature ratio of 0.48, and the RANS results are compared with those …


Application Of Metamaterials For Multifunctional Satellite Bus Enabled Via Additive Manufacturing, Michael A. Macchia 2019 Air Force Institute of Technology

Application Of Metamaterials For Multifunctional Satellite Bus Enabled Via Additive Manufacturing, Michael A. Macchia

Theses and Dissertations

Space systems require materials with superior stiffness to weight ratios to provide structural integrity while minimizing mass. Additive manufacturing processes enable the design of metamaterials that exceed the performance of naturally occurring materials in addition to allowing the integration of non-structural functions. This research explored the use of a high stiffness, high density, small melt pool track width AM material, Inconel 718, to enable the production of metamaterials with finer features possible than can possibly be created using a lower density aluminum alloy material. Various metamaterials were designed utilizing thin wall triply periodic minimal surface infilled sandwich structures. The performance …


Emerging Need For A European Approach To Space Traffic Management, Tomas Hrozensky 2019 European Space Policy Institute

Emerging Need For A European Approach To Space Traffic Management, Tomas Hrozensky

Space Traffic Management Conference

The intensification of space activities worldwide, together with the emergence of new actors and disruptive concepts (e.g. miniaturized satellites, mega-constellations, in-orbit operations), create new challenges to ensure the safety and security of space systems and operations as well as the long-term sustainability of space activities. Among policy responses to these challenges, the development of a new approach to space traffic management was recently brought to the forefront by the adoption of a policy directive in this domain by the United States.

A comparable STM policy has not yet been developed in Europe even though considerations for the safety, security and …


End To End Satellite Servicing And Space Debris Management, Aman Chandra, Himangshu Kalita, Roberto Furfaro, Jekan Thanga 2019 Univ. of Arizona

End To End Satellite Servicing And Space Debris Management, Aman Chandra, Himangshu Kalita, Roberto Furfaro, Jekan Thanga

Space Traffic Management Conference

There is growing demand for satellite swarms and constellations for global positioning, remote sensing and relay communication in higher LEO orbits. This will result in many obsolete, damaged and abandoned satellites that will remain on-orbit beyond 25 years. These abandoned satellites and space debris maybe economically valuable orbital real-estate and resources that can be reused, repaired or upgraded for future use. Space traffic management is critical to repair damaged satellites, divert satellites into warehouse orbits and effectively deorbit satellites and space debris that are beyond repair and salvage. Current methods for on-orbit capture, servicing and repair require a large service …


Advanced Inflatable De-Orbit Solutions For Derelict Satellites And Orbital Debris, Aman Chandra, Greg Wilburn, Jekan Thanga 2019 University of Arizona

Advanced Inflatable De-Orbit Solutions For Derelict Satellites And Orbital Debris, Aman Chandra, Greg Wilburn, Jekan Thanga

Space Traffic Management Conference

The exponential rise in small-satellites and CubeSats in Low Earth Orbit (LEO) poses important challenges for future space traffic management. At altitudes of 600 km and lower, aerodynamic drag accelerates de-orbiting of satellites. However, placement of satellites at higher altitudes required for constellations pose important challenges. The satellites will require on-board propulsion to lower their orbits to 600 km and let aerodynamic drag take-over. In this work we analyze solutions for de-orbiting satellites at altitudes of up to 3000 km. We consider a modular robotic de-orbit device that has stowed volume of a regular CubeSat. The de-orbit device would be …


Satellite Conjunction Assessment Risk Analysis For “Dilution Region” Events: Issues And Operational Approaches, Matthew D. Hejduk 2019 Astrorum Consulting LLC

Satellite Conjunction Assessment Risk Analysis For “Dilution Region” Events: Issues And Operational Approaches, Matthew D. Hejduk

Space Traffic Management Conference

An important activity within Space Traffic Management is the detection and prevention of possible on-orbit collisions between space objects. The principal parameter for assessing collision likelihood is the probability of collision, which is widely accepted among conjunction assessment practitioners; but it possesses a known deficiency in that it can produce a false sense of safety when the orbital position uncertainties for the conjuncting objects are high. The probability of collision is said to be “diluted” in such a situation and to understate the possible risk; certain approaches have been recommended by researchers to provide (largely conservative) risk estimates and remediation …


Astria Ontology: Open, Standards-Based, Data-Aggregated Representation Of Space Objects, Jennie Wolfgang, Kathleen Krysher, Michael Slovenski, Unmil P. Karadkar, Shiva Iyer, Moriba K. Jah 2019 The University of Texas at Austin

Astria Ontology: Open, Standards-Based, Data-Aggregated Representation Of Space Objects, Jennie Wolfgang, Kathleen Krysher, Michael Slovenski, Unmil P. Karadkar, Shiva Iyer, Moriba K. Jah

Space Traffic Management Conference

The necessity for standards-based ontologies for long-term sustainability of space operations and safety of increasing space flights has been well-established [6, 7]. Current ontologies, such as DARPA’s OrbitOutlook [5], are not publicly available, complicating efforts for their broad adoption. Most sensor data is siloed in proprietary databases [2] and provided only to authorized users, further complicating efforts to create a holistic view of resident space objects (RSOs) in order to enhance space situational awareness (SSA).

The ASTRIA project is developing an open data model with the goal of aggregating data about RSOs, parts, space weather, and governing policies in order …


Near Real Time Satellite Event Detection And Characterization With Remote Photoacoustic Signatures, Justin Spurbeck, Moriba K. Jah 2019 University of Texas at Austin

Near Real Time Satellite Event Detection And Characterization With Remote Photoacoustic Signatures, Justin Spurbeck, Moriba K. Jah

Space Traffic Management Conference

Active satellites frequently maneuver to mitigate conjunctions and maintain nominal mission orbits. With an ever-growing Resident Space Object (RSO) population, the need to detect and predict any changes in active RSO trajectories has become increasingly important. There is typically a lag on the order of hours to days from time of maneuver to unmodeled dynamic event detection depending on the magnitude of the delta-v. For uncooperative objects, this detection lag poses a threat to other satellites. Implementing an active photoacoustic signature change detection methodology to detect and predict unmodeled dynamic events would reduce the overall conjunction risk and provide a …


Lasers For Communication And Coordination Control Of Spacecraft Swarms, Himangshu Kalita, Leonard Dean Vance, Vishnu Reddy, Jekan Thanga 2019 University of Arizona

Lasers For Communication And Coordination Control Of Spacecraft Swarms, Himangshu Kalita, Leonard Dean Vance, Vishnu Reddy, Jekan Thanga

Space Traffic Management Conference

Swarms of small spacecraft offer whole new capabilities in Earth observation, global positioning and communications compared to a large monolithic spacecraft. These small spacecraft can provide bigger apertures that increase gain in communication antennas, increase area coverage or effective resolution of distributed cameras and enable persistent observation of ground or space targets. However, there remain important challenges in operating large number of spacecrafts at once. Current methods would require a large number of ground operators monitor and actively control these spacecraft which poses challenges in terms of coordination and control which prevents the technology from scaled up in cost-effective manner. …


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