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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 73 records · Page 4
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NASA NTRS2009

Cascade Distillation Subsystem Development: Early Results From the Exploration Life Support Distillation Technology Comparison Test

In 2009, the Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell International, Torrance, CA) was assessed in the National Aeronautics and Space Administration (NASA) Exploration Life Support (ELS) distillation comparison test. The purpose of the test was to collect data to support down-selection and development of a primary distillation technology for application in a lunar outpost water recovery system. The CDS portion of the comparison test was conducted between May 6 and August 19, 2009. The system was challenged with two pretreated test solutions, each intended to represent a feasible wastewater generated in a surface habitat. The 30-day equivalent wastewater loading volume for a crew of four was processed for each wastewater solution. Test Solution 1 consisted of a mixed stream containing human-generated urine and humidity condensate. Test Solution 2 contained the addition of human-generated hygiene wastewater to the solution 1 waste stream components. Approximately 1500 kg of total wastewater was processed through the CDS during testing. Respective recoveries per solution were 93.4 +/- 0.7 and 90.3 +/- 0.5%. The average specific energy of the system was calculated to be less than 130 W-hr/kg. The following paper provides detailed information and data on the performance of the CDS as challenged per the ELS distillation comparison test.

Callahan, Michael R.↗
NASA NTRS2009

A Lunar Surface System Supportability Technology Development Roadmap

This paper discusses the establishment of a Supportability Technology Development Roadmap as a guide for developing capabilities intended to allow NASA's Constellation program to enable a supportable, sustainable and affordable exploration of the Moon and Mars. Presented is a discussion of "supportability", in terms of space facility maintenance, repair and related logistics and a comparison of how lunar outpost supportability differs from the International Space Station. Supportability lessons learned from NASA and Department of Defense experience and their impact on a future lunar outpost is discussed. A supportability concept for future missions to the Moon and Mars that involves a transition from a highly logistics dependent to a logistically independent operation is discussed. Lunar outpost supportability capability needs are summarized and a supportability technology development strategy is established. The resulting Lunar Surface Systems Supportability Strategy defines general criteria that will be used to select technologies that will enable future flight crews to act effectively to respond to problems and exploit opportunities in a environment of extreme resource scarcity and isolation. This strategy also introduces the concept of exploiting flight hardware as a supportability resource. The technology roadmap involves development of three mutually supporting technology categories, Diagnostics Test & Verification, Maintenance & Repair, and Scavenging & Recycling. The technology roadmap establishes two distinct technology types, "Embedded" and "Process" technologies, with different implementation and thus different criteria and development approaches. The supportability technology roadmap addresses the technology readiness level, and estimated development schedule for technology groups that includes down-selection decision gates that correlate with the lunar program milestones. The resulting supportability technology roadmap is intended to develop a set of technologies with widest possible capability and utility with a minimum impact on crew time and training and remain within the time and cost constraints of the Constellation program

Oeftering, Richard C.↗
NASA NTRS2010

Portable Diagnostics Technology Assessment for Space Missions: General Technology Capabilities for NASA Exploration Missions - Part 1

The changes in the scope of NASA s mission in the coming decade are profound and demand nimble, yet insightful, responses. On-board clinical and environmental diagnostics must be available for both mid-term lunar and long-term Mars exploration missions in an environment marked by scarce resources. Miniaturization has become an obvious focus. Despite solid achievements in lab-based devices, broad-based, robust tools for application in the field are not yet on the market. The confluence of rapid, wide-ranging technology evolution and internal planning needs are the impetus behind this work. This report presents an analytical tool for the ongoing evaluation of promising technology platforms based on mission- and application-specific attributes. It is not meant to assess specific devices, but rather to provide objective guidelines for a rational down-select of general categories of technology platforms. In this study, we have employed our expertise in the microgravity operation of fluidic devices, laboratory diagnostics for space applications, and terrestrial research in biochip development. A rating of the current state of technology development is presented using the present tool. Two mission scenarios are also investigated: a 30-day lunar mission using proven, tested technology in 5 years; and a 2- to 3-year mission to Mars in 10 to 15 years.

Nelson, Emily S.↗
NASA NTRS2010

Cascade Distillation Subsystem Development: Early Results from the Exploration Life Support Distillation Technology Comparison Test

In 2009, the Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell International, Torrance, California) was assessed in the National Aeronautics and Space Administration (NASA) Exploration Life Support (ELS) distillation comparison test. The purpose of the test was to collect data to support down-selection and development of a primary distillation technology for application in a lunar outpost water recovery system. The CDS portion of the comparison test was conducted between May 6 and August 19, 2009. The system was challenged with two pretreated test solutions, each intended to represent a feasible wastewater generated in a surface habitat. The 30-day equivalent wastewater loading volume for a crew of four was intended to be processed for each wastewater solution. Test Solution 1 consisted of a mixed stream containing human-generated urine and humidity condensate. Test Solution 2 contained the addition of human-generated hygiene wastewater to the solution 1 waste stream components. Approximately 1500 kg of total wastewater was processed through the CDS during testing. Respective recoveries per solution were 93.4 +/- 0.7 and 90.3 +/- 0.5 percent. The average specific energy of the system during testing was calculated to be less than 120 W-hr/kg. The following paper provides detailed information and data on the performance of the CDS as challenged per the ELS distillation comparison test.

Callahan, Michael R.↗
NASA NTRS2010

A Densified Liquid Methane Delivery System for the Altair Ascent Stage

The Altair Lunar Lander is currently carrying options for both cryogenic and hypergolic ascent stage propulsion modules. The cryogenic option uses liquid methane and liquid oxygen to propel Altair from the lunar surface back to rendezvous with the Orion command module. Recent studies have determined that the liquid methane should be densified by subcooling it to 93 K in order to prevent over-pressurization of the propellant tanks during the 210 day stay on the lunar surface. A trade study has been conducted to determine the preferred method of producing; loading, and maintaining the subcooled, densified liquid methane onboard Altair from a ground operations perspective. The trade study took into account the limitations in mass for the launch vehicle and the mobile launch platform as well as the historical reliability of various components and their thermal efficiencies. Several unique problems were encountered, namely delivering a small amount of a cryogenic propellant to a flight tank that is positioned over 350 ft above the launch pad as well as generating the desired delivery temperature of the methane at 93 K which is only 2.3 K above the methane triple point of 90.7 K. Over 20 methods of subcooled liquid methane production and delivery along with the associated system architectures were investigated to determine the best solutions to the problem. The top four cryogenic processing solutions were selected for further evaluation and detailed thermal modeling. This paper describes the results of the preliminary trade analysis of the 20 plus methane densification methods considered. The results of the detailed analysis will be briefed to the Altair Project Office and their propulsion team as well as the Ground Operations Project Office before the down-select is made between cryogenic and hypergolic ascent stages in August 2010.

Tomsik, Thomas M.↗
NASA NTRS2010

Impact of Water Recovery from Wastes on the Lunar Surface Mission Water Balance

Future extended lunar surface missions will require extensive recovery of resources to reduce mission costs and enable self-sufficiency. Water is of particular importance due to its potential use for human consumption and hygiene, general cleaning, clothes washing, radiation shielding, cooling for extravehicular activity suits, and oxygen and hydrogen production. Various water sources are inherently present or are generated in lunar surface missions, and subject to recovery. They include: initial water stores, water contained in food, human and other solid wastes, wastewaters and associated brines, ISRU water, and scavenging from residual propellant in landers. This paper presents the results of an analysis of the contribution of water recovery from life support wastes on the overall water balance for lunar surface missions. Water in human wastes, metabolic activity and survival needs are well characterized and dependable figures are available. A detailed life support waste model was developed that summarizes the composition of life support wastes and their water content. Waste processing technologies were reviewed for their potential to recover that water. The recoverable water in waste is a significant contribution to the overall water balance. The value of this contribution is discussed in the context of the other major sources and loses of water. Combined with other analyses these results provide guidance for research and technology development and down-selection.

Fisher, John W.↗
NASA NTRS2010

Braze Development of Graphite Fiber for Use in Phase Change Material Heat Sinks

Hamilton Sundstrand (HS), together with NASA Johnson Space Center, developed methods to metallurgically join graphite fiber to aluminum. The goal of the effort was to demonstrate improved thermal conductance, tensile strength and manufacturability compared to existing epoxy bonded techniques. These improvements have the potential to increase the performance and robustness of phase change material heat sinks that use graphite fibers as an interstitial material. Initial work focused on evaluating joining techniques from 4 suppliers, each consisting of a metallization step followed by brazing or soldering of one inch square blocks of Fibercore graphite fiber material to aluminum end sheets. Results matched the strength and thermal conductance of the epoxy bonded control samples, so two suppliers were down-selected for a second round of braze development. The second round of braze samples had up to a 300% increase in strength and up to a 132% increase in thermal conductance over the bonded samples. However, scalability and repeatability proved to be significant hurdles with the metallization approach. An alternative approach was pursued which used nickel and active braze allows to prepare the carbon fibers for joining with aluminum. This approach was repeatable and scalable with improved strength and thermal conductance when compared with epoxy bonding.

Quinn, Gregory↗
NASA NTRS2011

Structural Design of Ares V Interstage Composite Structure

Preliminary and detailed design studies were performed to mature composite structural design concepts for the Ares V Interstage structure as a part of NASA s Advanced Composite Technologies Project. Aluminum honeycomb sandwich and hat-stiffened composite panel structural concepts were considered. The structural design and analysis studies were performed using HyperSizer design sizing software and MSC Nastran finite element analysis software. System-level design trade studies were carried out to predict weight and margins of safety for composite honeycomb-core sandwich and composite hat-stiffened skin design concepts. Details of both preliminary and detailed design studies are presented in the paper. For the range of loads and geometry considered in this work, the hat-stiffened designs were found to be approximately 11-16 percent lighter than the sandwich designs. A down-select process was used to choose the most favorable structural concept based on a set of figures of merit, and the honeycomb sandwich design was selected as the best concept based on advantages in manufacturing cost.

Sleigh, David W.↗
NASA NTRS2006

Potential Alternatives Report for Validation of Alternative Low-Emission Surface PreparationlDepainting Technologies for Structural Steel

For this project, particulates and solvents used during the depainting process of steel structures were the identified hazardous material (HazMat) targeted for elimination or reduction. This Potential Alternatives Report (PAR) provides technical analyses of identified alternatives to the current coating removal processes, criteria used to select alternatives for further analysis, and a list of those alternatives recommended for testing. The initial coating removal alternatives list was compiled using literature searches and center participant recommendations. The involved project participants initially considered fifteen (15) alternatives. In late 2004, stakeholders down-selected the list and identified specific processes as potential alternatives to the current depainting methods. The selected alternatives were: 1. Plastic Blast Media 2. Hard Abrasive Media 3. Sponge Blast Media 4. Mechanical Removal with Vacuum Attachment 5. Liquid Nitrogen 6. Laser Coating Removal Available information about these processes was used to analyze the technical merits and the potential environmental, safety, and occupational health (ESOH) impacts of these methods. A preliminary cost benefit analysis will be performed to determine if implementation of alternative technologies is economically justified. NASA AP2

Lewis, Pattie↗
NASA NTRS2011

Braze Development of Graphite Fiber for Use in Phase Change Material Heat Sinks

Hamilton Sundstrand (HS), together with NASA Johnson Space Center, developed methods to metallurgically join graphite fiber to aluminum. The goal of the effort was to demonstrate improved thermal conductance, tensile strength and manufacturability compared to existing epoxy bonded techniques. These improvements have the potential to increase the performance and robustness of phase change material heat sinks that use graphite fibers as an interstitial material. Initial work focused on evaluating joining techniques from four suppliers, each consisting of a metallization step followed by brazing or soldering of one inch square blocks of Fibercore graphite fiber material to aluminum end sheets. Results matched the strength and thermal conductance of the epoxy bonded control samples, so two suppliers were down-selected for a second round of braze development. The second round of braze samples had up to a 300% increase in strength and up to a 132% increase in thermal conductance over the bonded samples. However, scalability and repeatability proved to be significant hurdles with the metallization approach. An alternative approach was pursued which used a nickel braze allow to prepare the carbon fibers for joining with aluminum. Initial results on sample blocks indicate that this approach should be repeatable and scalable with good strength and thermal conductance when compared with epoxy bonding.

Quinn, Gregory↗
NASA NTRS2011

A Lunar Surface System Supportability Technology Development Roadmap

This paper discusses the establishment of a Supportability Technology Development Roadmap as a guide for developing capabilities intended to allow NASA s Constellation program to enable a supportable, sustainable and affordable exploration of the Moon and Mars. Presented is a discussion of supportability, in terms of space facility maintenance, repair and related logistics and a comparison of how lunar outpost supportability differs from the International Space Station. Supportability lessons learned from NASA and Department of Defense experience and their impact on a future lunar outpost is discussed. A supportability concept for future missions to the Moon and Mars that involves a transition from a highly logistics dependent to a logistically independent operation is discussed. Lunar outpost supportability capability needs are summarized and a supportability technology development strategy is established. The resulting Lunar Surface Systems Supportability Strategy defines general criteria that will be used to select technologies that will enable future flight crews to act effectively to respond to problems and exploit opportunities in an environment of extreme resource scarcity and isolation. This strategy also introduces the concept of exploiting flight hardware as a supportability resource. The technology roadmap involves development of three mutually supporting technology categories, Diagnostics Test and Verification, Maintenance and Repair, and Scavenging and Recycling. The technology roadmap establishes two distinct technology types, "Embedded" and "Process" technologies, with different implementation and thus different criteria and development approaches. The supportability technology roadmap addresses the technology readiness level, and estimated development schedule for technology groups that includes down-selection decision gates that correlate with the lunar program milestones. The resulting supportability technology roadmap is intended to develop a set of technologies with widest possible capability and utility with a minimum impact on crew time and training and remain within the time and cost constraints of the Constellation program.

Oeftering, Richard C.↗
NASA NTRS2011

Optimizing Spacecraft Placement for Liaison Constellations

A navigation and communications network is proposed to support an anticipated need for infrastructure in the Earth-Moon system. Periodic orbits will host the constellations while a novel, autonomous navigation strategy will guide the spacecraft along their path strictly based on satellite-to-satellite telemetry. In particular, this paper investigates the second stage of a larger constellation optimization scheme for multi-spacecraft systems. That is, following an initial orbit down-selection process, this analysis provides insights into the ancillary problem of spacecraft placement. Two case studies are presented that consider configurations of up to four spacecraft for a halo orbit and a cycler trajectory.

lunar cycler orbits↗
NASA NTRS2012

Non-Toxic, Low-Freezing, Drop-In Replacement Heat Transfer Fluids

A non-toxic, non-flammable, low-freezing heat transfer fluid is being developed for drop-in replacement within current and future heat transfer loops currently using water or alcohol-based coolants. Numerous water-soluble compounds were down-selected and screened for toxicological, physical, chemical, compatibility, thermodynamic, and heat transfer properties. Two fluids were developed, one with a freezing point near 0 C, and one with a suppressed freezing point. Both fluids contain an additive package to improve material compatibility and microbial resistance. The optimized sub-zero solution had a freezing point of 30 C, and a freezing volume expansion of 10-percent of water. The toxicity of the solutions was experimentally determined as LD(50) greater than 5g/kg. The solutions were found to produce minimal corrosion with materials identified by NASA as potentially existing in secondary cooling loops. Thermal/hydrodynamic performance exceeded that of glycol-based fluids with comparable freezing points for temperatures Tf greater than 20 C. The additive package was demonstrated as a buffering agent to compensate for CO2 absorption, and to prevent microbial growth. The optimized solutions were determined to have physically/chemically stable shelf lives for freeze/thaw cycles and longterm test loop tests.

Cutbirth, J. Michael↗
NASA NTRS2012

Implementation of a Transition Model in a NASA Code and Validation Using Heat Transfer Data on a Turbine Blade

The purpose of this report is to summarize and document the work done to enable a NASA CFD code to model laminar-turbulent transition process on an isolated turbine blade. The ultimate purpose of the present work is to down-select a transition model that would allow the flow simulation of a variable speed power turbine to be accurately performed. The flow modeling in its final form will account for the blade row interactions and their effects on transition which would lead to accurate accounting for losses. The present work only concerns itself with steady flows of variable inlet turbulence. The low Reynolds number k- model of Wilcox and a modified version of the same model will be used for modeling of transition on experimentally measured blade pressure and heat transfer. It will be shown that the k- model and its modified variant fail to simulate the transition with any degree of accuracy. A case is thus made for the adoption of more accurate transition models. Three-equation models based on the work of Mayle on Laminar Kinetic Energy were explored. The three-equation model of Walters and Leylek was thought to be in a relatively mature state of development and was implemented in the Glenn-HT code. Two-dimensional heat transfer predictions of flat plate flow and two-dimensional and three-dimensional heat transfer predictions on a turbine blade were performed and reported herein. Surface heat transfer rate serves as sensitive indicator of transition. With the newly implemented model, it was shown that the simulation of transition process is much improved over the baseline k- model for the single Reynolds number and pressure ratio attempted; while agreement with heat transfer data became more satisfactory. Armed with the new transition model, total-pressure losses of computed three-dimensional flow of E3 tip section cascade were compared to the experimental data for a range of incidence angles. The results obtained, form a partial loss bucket for the chosen blade. In time the loss bucket will be populated with losses at additional incidences. Results obtained thus far will be discussed herein.

Ameri, Ali A.↗
NASA NTRS2012

Computational Work to Support FAP/SRW Variable-Speed Power-Turbine Development

The purpose of this report is to document the work done to enable a NASA CFD code to model the transition on a blade. The purpose of the present work is to down-select a transition model that would allow the flow simulation of a Variable-Speed Power-Turbine (VSPT) to be accurately performed. The modeling is to be ultimately performed to also account for the blade row interactions and effect on transition and therefore accurate accounting for losses. The present work is limited to steady flows. The low Reynolds number k-omega model of Wilcox and a modified version of same will be used for modeling of transition on experimentally measured blade pressure and heat transfer. It will be shown that the k-omega model and its modified variant fail to simulate the transition with any degree of accuracy. A case is therefore made for more accurate transition models. Three-equation models based on the work of Mayle on Laminar Kinetic Energy were explored and the Walters and Leylek model which was thought to be in a more mature state of development is introduced and implemented in the Glenn-HT code. Two-dimensional flat plate results and three-dimensional results for flow over turbine blades and the resulting heat transfer and its transitional behavior are reported. It is shown that the transition simulation is much improved over the baseline k-omega model.

Ameri, Ali A.↗
NASA NTRS2011

2011 Mars Science Laboratory Launch Period Design

The Mars Science Laboratory mission, set to launch in the fall of 2011, has the primary objective of landing the most advanced rover to date to the surface of Mars to assess whether Mars ever was, or still is today, able to sustain carbon-based life. Arriving at Mars in August 2012, the Mars Science Laboratory will also demonstrate the ability to deliver large payloads to the surface of Mars, land more accurately (than previous missions) in a 20-km by 25-km ellipse, and traverse up to 20 km. Following guided entry and parachute deployment, the spacecraft will descend on a parachute and a Powered Descent Vehicle to safely land the rover on the surface of Mars. The launch/arrival strategy is driven by several key requirements, which include: launch vehicle capability, atmosphere-relative entry speed, communications coverage during Entry, Descent and Landing, latitude accessibility, and dust storm season avoidance. Notable among these requirements is maintaining a telecommunications link from atmospheric entry to landing plus one minute, via a Direct-To-Earth X-band link and via orbital assets using an UHF link, to ensure that any failure during Entry, Descent and Landing can be reconstructed in case of a mission anomaly. Due to concerns related to the lifetime of the relay orbiters, two additional launch/arrival strategies have been developed to improve Entry, Descent, and Landing communications. This paper discusses the final launch/arrival strategy selected prior to the launch period down-selection that is scheduled to occur in August 2011. It is also important to note that this paper is an update to Ref. 1 in that it includes two new Type 1 launch periods and drops the Type 2 launch period that is no longer considered.

mission design↗
NASA NTRS2011

Rotary Wing Deceleration Use on Titan

Rotary wing decelerator (RWD) systems were compared against other methods of atmospheric deceleration and were determined to show significant potential for application to a system requiring controlled descent, low-velocity landing, and atmospheric research capability on Titan. Design space exploration and down-selection results in a system with a single rotor utilizing cyclic pitch control. Models were developed for selection of a RWD descent system for use on Titan and to determine the relationships between the key design parameters of such a system and the time of descent. The possibility of extracting power from the system during descent was also investigated.

Young, Larry A.↗
NASA NTRS2012

MAARSS: Magnet Architectures and Active Radiation Shielding Study

Protecting humans from space radiation is a major hurdle for human exploration of the solar system and beyond. Like on Earth, large magnetic fields surrounding a spaceship would deflect charged particles away from the habitat region and reduce the radiation dose to acceptable limits. The objective of this study is to determine the feasibility of current state of the art (SOA) high temperature superconducting (HTS) magnets as a means to protect crew from space radiation exposure on long duration missions beyond Low Earth Orbit (LEO). The study will look at architecture concepts to deflect high energy Galactic Cosmic Radiation (GCR) and Solar Proton Events (SPEs). Mass, power, and shielding efficiency will be considered and compared with current passive shielding capabilities. This report will walk the reader through several designs considered over the one year study and discuss the multiple parameters that should be evaluated for magnetic shielding. The study team eventually down-selects to a scalable light weight solenoid architecture that is launchable and then deployable using magnetic pressure to expand large diameter coils. Benefitting from the low temperature and high vacuum environment of deep space, existing high-temperature superconductors make such radiation shields realistic, near-term technical developments.

Westover, Shayne C.↗