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| University of Puerto Rico at Rio Piedras |
| 2011 |
| Diffusional Effects in Nanomaterials |
| The dissusion of molecular species through nanoporous systems in microgravity conditions is of interest due to the implications of nanotechnology in aerospace technologies. The herein proposed study will provide insights on the diffusion processes in enabling technologies such as Li batteries, Fuel Cells, and nano-based wastewater purification systems. In general, the fundamental experiment to be studied is the ammonia oxidation at Pt nanoparticles/nano-supporting electrode systems. This system is currently being studied at the NASA-URC Center for Advanced Nanoscale Materials interdisciplinary research group in nanomaterials for Life Support Systems. The microgravity experiment will involve the measurement of current as a function of time at an applied potential needed for the oxidation of ammonia. The diffusional coefficient (Do) of ammonia/ammonium ion will be assessed under different supporting materials such as: Carbon Vulcan XC-72R, Carbon Nano-onions (CNO) and Carbon Nanotubes (CNT's). These materials will provide both different pore size and structure and also electronic and chemical properties that will be correlated to the diffusion of species. Due to the truly diffusional environment under micro-g conditions the diffusion of species through the nonmaterial network is expected to change and will be quantified. The electrochemical cell to be employed consists of a working electrode, an Ag quasi-reference electrode, and a Pt mesh counter electrode. The working electrode consists of an ionomer/carbon powder/Pt nanoparticle paste on the 1cm2 glassy carbon electrode. A secondarycontainment will be used for any possible spill. This experiment will shed light on the diffusion of ammonia/ammonium ions under microgravity conditions for state-of-the art materials currently at the frontier of science. |
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| University of Texas @ El Paso |
| 2011 |
| SEED - Feasibility and Reliability of Construction Techniques |
| SEED - Feasibility and Reliability of Construction Techniques |
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| University of Texas @ El Paso |
| 2011 |
| Structural Materials from Lunar Regolith |
| In-situ resource utilization is an enabling technology for future missions to the Moon, Mars, and beyond. Construction materials for landing/launching pads, radiation shielding, and other structures on the lunar/planetary surface can be produced from regolith. The project deals with the production of ceramic composites from lunar regolith simulant using combustion synthesis, also called self-propagating high-temperature synthesis (SHS). In this method, the regolith simulant is mixed with metals that can react exothermically with the simulant. Thus, upon ignition, self-sustained combustion occurs, leading to the formation of ceramic composites. This process may be affected by gravity due to the presence of liquid metal in the combustion front and natural convection in gas phase around the sample. The project will investigate the gravity effect on the combustion wave propagation and the product structure for the mixtures of lunar regolith simulant with magnesium. During parabolic flights, the mixture samples will be burned in a closed chamber filled with argon. The combustion front velocity will be measured using video recording. After the flights, the product composition and microstructure will be investigated. The obtained data will be compared with the front velocities and product structures obtained in 1-g experiments. Based on this comparison, the conclusion on the effect of gravity on the combustion of regolith/magnesium mixtures will be made. |
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| University of Washington |
| 2011 |
| Reduced-Gravity Fluid Transfer Experiment |
| Often, equipment intended for terrestrial applications do not work as designed when subjected to microgravity conditions. This presents a unique problem to engineers and designers when creating hardware from which functionality in space is required. Liquid containment systems require special consideration in this regard. Major problems associated with fluid handling in microgravity include the transfer and volume measurement of the contained liquids. The current technologies used to measure and transfer fuel in many terrestrial vehicles include basic fuel pumps and floats. However, these devices were not designed to function in microgravity, and therefore do not operate properly under these conditions. Students at the University of Washington have identified a method to potentially solve many of the problems experienced with the transfer and measurement of liquid in microgravity. Building off the success of our colleagues' experiment in developing the Rotational Damping of Slosh in Microgravity (RDSM) mechanism [5] in the 2009-2010 NASA- Microgravity University program, we have designed a system that transfers and measures liquid in a rotating fluid tank. This experiment utilizes the physical principle that the centripetal force induced by the rotating tank in reduced gravity causes the liquid inside to stabilize and gather on the inner wall of the tank. By [INVALID]ing capacitance sensors through the walls of the tank, the difference between the dielectric constants of the air and liquid inside the tank allow for the liquid volume in the tank to be determined. Furthermore, the rotating tank and its tapered geometry cause the liquid to accumulate towards one end of the tank. Because of this, a tube can be [INVALID]ed into this reservoir and the liquid can be extracted via a small pump and transferred to a secondary collection tank. The flow out of the tank will be measured using a volume flow rate meter, and verified by measuring the fluid collected in the secondary collection tank once gravity is restored. This fairly simple system allows for measurement and transfer of large or small quantities of liquid. |
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| University of Wisconsin @ Madison |
| 2011 |
| SEED - Electric Capacitance Volumetric Tomography for Fuel Gauging |
| SEED - Electric Capacitance Volumetric Tomography for Fuel Gauging |
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| UT - Utah State University |
| 2011 |
| FUNBOE 2.0 Follow-Up Nucleate Boiling On-flight Experiment |
| As mankind continues to explore space, there is an increasing need for reliable, more cost-effective thermal management systems. Due to the high heat transfer rates associated with nucleate boiling, this process could prove to be a viable option for such microgravity systems. However, further experimentation in microgravity environments is needed to understand the fundamental effects of system parameters on nucleate boiling dynamics and determine its range of applicability. FUNBOE 2.0 is a follow-up study to the original FUNBOE project that was flown during the 2009-2010 RGSFOP program. FUNBOE provided many insights to the nucleate boiling phenomenon that were previously unreported. While FUNBOE found many interesting boiling characteristics, FUNBOE 2.0 seeks to explore several of these results in more detail, including: i. Investigating a broader range of heat fluxes to completely map the boiling curve and investigating bubble jets especially near the critical heat flux (CHF) ii. Further resolving the minimum heat flux required to initiate boiling for various heating element surface geometries and the associated pre-boiling and boiling characteristics iii. Extrapolating the understandings of thin-wire boiling developed with FUNBOE by testing the effectiveness of creating seed bubbles with a 2-D array of microheaters in order to enhance cooling. |
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| Washington University in Saint Louis |
| 2011 |
| SEED - In-flight Carbon Dioxide Monitoring Capability |
| SEED - In-flight Carbon Dioxide Monitoring Capability |
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| West Virginia University |
| 2011 |
| Electro-Magnetically Enhanced Cylindrical Fluidized Bed in Microgravity |
| Fluidized beds are a current technology used to achieve high levels of contact between a solid particulate and a flowing gas or liquid. This technology has been implemented in various applications ranging from filtering to combustion. While it has proven benefits in an environment where the gravitational force is influential, minimal research of fluidized beds in a microgravity environment has been conducted. This is a critical issue as this technology may have the potential to be utilized in microgravity for the same range of applications as on Earth. Two distinct methodologies have attempted in previous work to simulate the gravitational force in microgravity by: A.) directing a Coulomb force and B.) use of an electromagnetic gradient field on charged particles. The latter demonstrated that it is possible to replace the gravitational force by an electromagnetic force. This current research effort intends to enhance the performance of the previous works by incorporating a rotating time-dependent electromagnetic field. Inducing a rotating magnetic configuration is theorized to increase the amount of mixing between the solid particulate and the fluid, air. Further mixing between the two phases will increase the effective reaction surface area thereby optimizing the efficiency of the fluidized bed when utilized in microgravity applications. A rotating fluidized bed can be enhanced by many variables including, but not limited to, the mass flow rate of the flowing gas or air and the angular rate of the rotating electromagnetic field. Rather than have a physically rotating mechanical device to induce the field, the rotating field will be formed by switching a series of coils on and off at specified time intervals, corresponding to the electromagnetic angular rate. A decrease in the time interval is expected to increase the mixing between the particles and the air up to a threshold, where eventually reducing the time interval any further may negatively impact the mixing. An increase in the flowing gas rate supports an increase in surface area interaction, although is limited by a similar threshold. This work is a culminating effort to create optimized reaction mixture techniques for future space-based microgravity applications in which filtration and/or chemical reactions must be optimized. |
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| Yale University |
| 2011 |
| The Influence of Gravitational Variations on Solidification of Fluids and the Formation of Mushy Layers |
| When fluids are solidified in microgravity, many of the underlying processes that lead to [INVALID]rious effects when the same systems are crystallized on Earth can be avoided. Understanding the fundamental physical processes governing the solidification of multi-component fluids and the formation of so-called mushy layers also has wide application to oceanography, materials science, and planetary science. NASA frequently sponsors experiments on the solidification of ice crystals or binary alloys, some of which have been performed aboard the International Space Station. The proposed experiment aims to quantify the effects of various gravitational conditions on the solidification of a transeutectic sodium acetate solution. This experiment is ideal for parabolic flight because its science goals benefit greatly from data collection in the four different accessible gravity conditions and the solidification time scales are the same as the length of a typical microgravity episode. Video of the solidification and other fluid mechanical processes is collected with a high-speed, high-resolution camera. Solidified samples will be analyzed after the flight to determine crystal grain size and the abundance of channels or macrodefects. The test article is engineered to safely and efficiently achieve the experiment's science goals. An extensive outreach program is proposed to inspire younger students, including historically underrepresented populations, to pursue further education and careers in STEM fields. |
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| Auburn University |
| 2010 |
| Complex Flow of Granular Lunar Soil Simulant |
| SEED Project |
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