Results for “technological readiness” — Page 57

NASA NTRS2018

Measurement of Noise Reduction from Acoustic Casing Treatments Installed over a Subscale High Bypass Ratio Turbofan Rotor

NASA is continuing to develop over-the-rotor acoustic liners for turbofan applications. A series of low Technology Readiness Level experiments were conducted to better understand the acoustic and aerodynamic effects of these acoustic liners. The final experiment included the evaluation of four acoustic casing treatment concepts and two baseline configurations in an internal flow axial compressor facility with a 1.5 pressure-ratio high-bypass turbofan rotor. An inlet in-duct array was utilized to extract sound power levels propagating forward from the turbofan rotor. The effect of a circumferentially grooved relative to a hardwall fan case was found to reduce the in-duct sound power level by about 1.5dB for frequencies less than 2kHz while increasing noise from 4 to 8kHz by as much as 7.5dB at low fan speeds. The four acoustic treatment concepts were incorporated into the bottoms of the circumferential grooves and found to provide an additional 1 to 2dB sound power level reduction under 2kHz. The sound power level reduction was found to be even greater, 2.5 to 3.5dB, when evaluating the reduction on rotor alone duct modes (co-rotating modes). The acoustic treatments also appeared to reduce multiple pure tone noise at transonic fan speeds. Depending on the acoustic treatment concept, the high-frequency noise created by the circumferential grooves was reduced by 1.5 to 5 dB. The total noise reduction from acoustic treatments embedded into the bottoms of circumferential grooves relative to a hardwall baseline was found to be 2.5 to 3.5dB sound power level. The sound power level reduction for rotor alone (co-rotating) modes was found to be 3.5 to 4.5dB. These results show the potential for significant turbofan noise reduction by incorporating acoustic treatments over-the-rotor.

Noise↗

NASA NTRS2017

Design Process of a Pressure Transducer Vibration Fixture

This paper details the iterative design cycle of a fixture used to mount two types of pressure transducers for vibration testing which allows for functional testing without the removal of the transducers. The objective of the fixture is to prove that the pressure transducers can survive vibrations induced during launch. This would increase the Technology Readiness Level of the pressure transducers which is a requirement for the Lunar Advanced Volatile Analysis subsystem preliminary design review. During the design process, additive manufacturing is considered as a manufacturing method of the fixture as a way to investigate the use of additive manufacturing for the final flight version of the Fluid Sub System manifold. It is ultimately shown that the added ability to perform functional testing and optimization for additive manufacturing made the fixture less than ideal for vibration testing. It is determined that the best option is to design and manufacture a traditional vibration fixture without the ability to perform functional testing of components while attached and a separate part to investigate the application of additive manufacturing to the Fluid Subsystem manifold.

Gilstrap, Andrew↗

NASA NTRS2017

100 kW Nested Hall Thruster System Development

Large scale cargo transportation to support human missions to the Moon and Mars will require very high power Solar Electric Propulsion (SEP) systems operating between 200 and 400 kW. Aerojet Rocketdyne's NextSTEP program is developing and demonstrating a 100 kW EP system, the XR-100, using a Nested Hall Thruster (NHT) designed for powers up to 200 kW, a modular power processor and a modular flow controller. The three year program objective is to operate the integrated EP system continuously at 100 kW for 100 h, advancing this very high power Electric Propulsion (EP) system to Technology Readiness Level (TRL) 5. With our University of Michigan, Jet Propulsion Laboratory and NASA Glenn Research Center teammates, Aerojet Rocketdyne has completed the initial phase of the program, including operating the thruster at up to 30 kW to validate the thermal models and developing and operating multiple power processor modules in the required seriesparallel configuration. The current phase includes completing a TRL 4 integrated system test at reduced power to validate all system operating phases. Design upgrades to demonstrate the TRL 5 capabilities are underway. This paper will present the high power XR-100 capabilities, overall program and design approach and the latest test results for the 100 kW EP system demonstration program.

Jackson, Jerry↗

NASA NTRS2018

Fiber-Based Laser Transmitter Technology Maturation for Spectroscopic Measurements from Space

NASA's Goddard Space Flight Center has been developing lidar to remotely measure CO2 in the Earth's atmosphere. We have advanced the tunable laser technology to enable high-fidelity measurements from space. In this paper, we will report on the progress of fiber-based, 1.57-micron wavelength, laser transmitter that has demonstrated the optical performance required for a low earth orbiting instrument. The Laser transmitter has been packaged and is undergoing environmental testing to demonstrate its technology readiness for space.

Stephen, Mark↗

NASA NTRS2018

Power Processing and Flow Control for a 100 kW Hall Thruster System

Aerojet Rocketdyne's NextSTEP program is developing and demonstrating a 100 kW Electric Propulsion (EP) system, the XR-100, which includes a modular power processing unit and modular xenon feed system to operate a Nested Hall Thruster (NHT) designed for powers up to 200 kW. The NextSTEP system is intended for use on large scale cargo transportation to support human missions to the Moon and Mars, which require very high-power Solar Electric Propulsion (SEP) systems operating between 200 and 400 kW. The three-year program objective is to operate the integrated EP system continuously at 100 kW for 100 hours, advancing this very high-power EP system to Technology Readiness Level (TRL) 5. In order to process the power and control propellant flow for this high-power system, Aerojet Rocketdyne has developed a modular concept for the Power Processing Units (PPUs) and Xenon feed system. The program has completed testing of critical elements of the PPU and feed system with a thruster simulator. Design upgrades to demonstrate the TRL 5 capabilities are underway. This paper will present an overview of the program and system design approach, the high power XR-100 capabilities of the PPU and feed system, and the latest test results for the 100 kW EP system demonstration program. In order to successfully execute this contract, there is a close collaboration between the teammates at Aerojet Rocketdyne (AR), the University of Michigan (UM), the NASA Jet Propulsion Laboratory (JPL), and the NASA Glenn Research Center (GRC).

Soendker, Erich↗

NASA NTRS2018

Hydroponics for Food Production in Space: History and Current Efforts

Goals of Food Production in Space: NASA Human Research Program (HRP) near-term food production systems - supplement key nutrients (Vitamins B1,C, K and potassium) that degrade to inadequate levels on exploration class missions; Study behavioral health aspect - caring for plants and improving the acceptability of the astronaut diet by supplementing it with fresh produce (currently anecdotal); Develop sustainable water delivery technologies - current TRL (Technological Readiness Level) 9 particulate based systems (i.e. used in research conducted in plant growth facilities APH (Advanced Plant Habitat), Veggie, BPS (Biomass Production System), LADA/SVET (Russian space plant chamber systems)) require resupply of bulky consumables and generate waste media.

Dreschel, T.↗

NASA NTRS2018

Update on the Nested Hall Thruster Subsystem for the NextSTEP XR-100 Program

Under the NextSTEP program led by Aerojet Rocketdyne in collaboration with NASA Glenn Research Center the University of Michigan, and the Jet Propulsion Laboratory, the XR-100 100 kW Electric Propulsion system is being developed to Technology Readiness Level (TRL) 5. As part of this program, the X3, a Nested Hall Thruster (NHT) designed to operate at powers up to 200kW, is being further developed through parallel modeling and experimental efforts with the ultimate goal of supporting a 100kW-100hr system test in the final year of the NextSTEP program. Recent developments for the X3 subsystem are presented including a summary of testing and modeling results and design updates in anticipation of a risk reduction test scheduled for the summer of 2018.

Jorns, Benjamin A.↗

NASA NTRS2018

A Comparison of Energy Conversion Technologies for Space Nuclear Power Systems

A key element of space nuclear power systems is the energy conversion subsystem that converts the nuclear heat into electrical power. Nuclear systems provide a favorable option for missions that require long-duration power in hostile space environments where sunlight for solar power is absent or limited. There are two primary nuclear power technology options. Radioisotope Power System (RPS) utilize the natural decay heat from Pu238 to generate electric power levels up to about one kilowatt. Fission Power System (FPS) rely on a sustained fission reaction of U235 and offer the potential to supply electric power from kilowatts to megawatts. Example missions for nuclear power include Mars science rovers (e.g. Curiosity, Mars 2020), lunar and Mars surface landers ? including crewed missions, deep space planetary orbiters, Ocean World science landers, and robotic space probes that utilize nuclear electric propulsion. This paper examines the energy conversion technology options that can be used with RPS and FPS, and provides an assessment of their relative performance and technology readiness.

Mason, Lee S.↗

NASA NTRS2018

Measurement of Noise Reduction from Acoustic Casing Treatments Installed Over a Subscale High Bypass Ratio Turbofan Rotor

NASA is continuing to develop over-the-rotor acoustic liners for turbofan applications. A series of low Technology Readiness Level experiments were conducted to better understand the acoustic and aerodynamic effects of these acoustic liners. The final experiment included the evaluation of four acoustic casing treatment concepts and two baseline configurations in an internal flow axial compressor facility with a 1.5 pressure-ratio high-bypass turbofan rotor. An inlet in-duct array was utilized to extract sound power levels propagating forward from the turbofan rotor. The effect of a circumferentially grooved relative to a hardwall fan case was found to reduce the in-duct sound power level by about 1.5dB for frequencies less than 2kHz while increasing noise from 4 to 8kHz by as much as 7.5dB at low fan speeds. The four acoustic treatment concepts were incorporated into the bottoms of the circumferential grooves and found to provide an additional 1 to 2dB sound power level reduction under 2kHz. The sound power level reduction was found to be even greater, 2.5 to 3.5dB, when evaluating the reduction on rotor alone duct modes (co-rotating modes). The acoustic treatments also appeared to reduce multiple pure tone noise at transonic fan speeds. Depending on the acoustic treatment concept, the high-frequency noise created by the circumferential grooves was reduced by 1.5 to 5 dB. The total noise reduction from acoustic treatments embedded into the bottoms of circumferential grooves relative to a hardwall baseline was found to be 2.5 to 3.5dB sound power level. The sound power level reduction for rotor alone (co-rotating) modes was found to be 3.5 to 4.5dB. These results show the potential for significant turbofan noise reduction by incorporating acoustic treatments over-the-rotor.

Aeroacoustics↗

NASA NTRS2018

Polar Volatiles Exploration in Peary Crater Enabled by NASA's Kilopower Project

For more than 50 years, scientists have discussed the possibility of the existence of water ice and other frozen volatiles at the lunar poles [1]. However, it was not until the 1990s when the polar orbiting spacecraft Clementine and Lunar Prospector collected data supporting these hypotheses [2]. Subsequent missions, including the Lunar Reconnaissance Orbiter (LRO) mission [3], and the Lunar Crater Observation and Sensing Satellite (LCROSS) mission [4], provided further evidence that supports the existence of water ice deposits at the lunar poles. During NASA's Constellation Program, several areas at both lunar poles polar were included in 50 Regions of Interest (ROI) for intensive study by the Lunar Reconnaissance Orbiter Camera (LROC) [5]. These polar ROI focused on peaks and craters rims that received high amounts of solar illumination, assuming initial missions back to the lunar surface would utilize solar arrays to generate electricity. Recently, the successful demonstration of NASA's Kilopower Project at the National Nuclear Security Administration (NNSA) Nevada National Security Site makes it possible to consider lunar polar missions at locations other than highly illuminated regions. The Kilopower Project was initiated in 2015 to demonstrate subsystem-level technology readiness of a small space fission power system [6]. This abstract describes the science objectives and operations for a mission concept developed at NASA Glenn Research Center's COMPASS Concurrent Engineering Team for a 1-year exploration of Peary Crater focused on prospecting for lunar polar volatiles.

Gruener, J. E.↗

NASA NTRS2018

Power Processing and Flow Control for a 100 kW Hall Thruster System

Aerojet Rocketdyne's NextSTEP program is developing and demonstrating a 100 kW Electric Propulsion (EP) system, the XR-100, which includes a modular power processing unit and modular xenon feed system to operate a Nested Hall Thruster (NHT) designed for powers up to 200 kW. The NextSTEP system is intended for use on large scale cargo transportation to support human missions to the Moon and Mars, which require very high-power Solar Electric Propulsion (SEP) systems operating between 200 and 400 kW. The three-year program objective is to operate the integrated EP system continuously at 100 kW for 100 hours, advancing this very high-power EP system to Technology Readiness Level (TRL) 5. In order to process the power and control propellant flow for this high-power system, Aerojet Rocketdyne has developed a modular concept for the Power Processing Units (PPUs) and Xenon feed system. The program has completed testing of critical elements of the PPU and feed system with a thruster simulator. Design upgrades to demonstrate the TRL 5 capabilities are underway. This paper will present an overview of the program and system design approach, the high power XR-100 capabilities of the PPU and feed system, and the latest test results for the 100 kW EP system demonstration program. In order to successfully execute this contract, there is a close collaboration between the teammates at Aerojet Rocketdyne (AR), the University of Michigan (UM), the NASA Jet Propulsion Laboratory (JPL), and the NASA Glenn Research Center (GRC).

Hablitzel, Sam↗

NASA NTRS2018

Update on the Nested Hall Thruster Subsystem for the NextSTEP XR-100 Program

Under the NextSTEP program led by Aerojet Rocketdyne in collaboration with NASA Glenn Research Center the University of Michigan, and the Jet Propulsion Laboratory, the XR-100 100 kW Electric Propulsion system is being developed to Technology Readiness Level (TRL) 5. As part of this program, the X3, a Nested Hall Thruster (NHT) designed to operate at powers up to 200kW, is being further developed through parallel modeling and experimental efforts with the ultimate goal of supporting a 100kW-100hr system test in the final year of the NextSTEP program. Recent developments for the X3 subsystem are presented including a summary of testing and modeling results and design updates in anticipation of a risk reduction test scheduled for the summer of 2018.

Jorns, Benjamin A.↗

NASA NTRS2018

NASA GRC Compass Team Conceptual Point Design and Trades of a Hybrid Solar Electric Propulsion (SEP)/Chemical Propulsion Human Mars Deep Space Transport (DST) Vehicle

NASA has long been conducting studies which apply different in-space propulsion technology assumptions to the mission of sending humans to Mars. Two of the technologies under study that are considered to be the most near-term with respect to technology readiness level (TRL) are traditional chemical propulsion systems and high-power Solar Electric Propulsion (SEP) systems. The benefit of relatively low trip times inherent in using impulsive chemical propulsion systems to perform the full round-trip delta V is hampered by the large propellant mass required to perform these burns for human Mars missions. SEP systems offer the benefit of much lower propellant requirements to perform the same round-trip missions, at the cost of longer trip times. Traditionally, impulsive chemical systems are better suited than SEP when used in a gravity well, and SEP systems are more efficient than traditional impulsive systems when used in interplanetary space. A mission to Mars includes both of these scenarios, and thus several NASA architecture studies performed over the last few years have looked to combine the use of both SEP and chemical propulsion systems where they are the most beneficial to human Mars missions. This combined propulsion system concept has been referred to as a SEP/Chem hybrid Mars Transfer Vehicle and is currently shown as the concept Deep Space Transport (DST) in the March 2017 NASA presentation to the National Aerospace Council (NAC).

human exploration↗

NASA NTRS2014

Thermal Testing of Thermal Protection System (TPS) Materials

High temperature testing of thermal protection system (TPS) materials is a critical aspect of heat-shield materials development, as it determines the suitability and performance envelope of the materials. The present talk provides an overview of different high temperature test facilities that are available for conducting thermal tests for TPS materials. The facilities include arcjet testing, solar tower testing facilities and laser test facility. The facilities are selected based on the requirements and objectives of the tests and each have their benefits and limitations. The paper also describes the process of determining the test environments based on mission profiles and requirements. Some of the recent thermal tests of TPS materials are discussed in this paper. These tests have helped improve the TRL (Technology Readiness Level) level of novel TPS materials and make them viable TPS material candidates for future missions.

Thermal Protection Materials↗

NASA NTRS2019

Electric Sail Tether Deployment System for CubeSats

An Electric Sail (E-Sail) propulsion system consists of long, thin tethers - positively-charged wires extending radially and symmetrically outward from a spacecraft. Tethers must be biased using a high-voltage power supply to ensure that the solar wind produces thrust. While the E-Sail concept shows great promise for flying heliopause missions with higher characteristic acceleration than solar sails, there are significant technical challenges related to deploying and controlling multiple tethers. A typical full-scale design involves a hub and spoke arrangement of 10 to 100 tethers, each 20 km long. In the last 20 years, there have been multiple space mission failures due to tether deployment and control issues, and most configurations involved a single tether. This paper describes an effort to develop and test a simple yet robust single-tether deployment system for a two-6U CubeSat configuration. The project included the following: a) Tether dynamic modeling/simulation b) E-Sail single-tether prototype development and testing c) Space environmental effects testing to identify best materials for further development. These three areas of investigation were needed to provide technical rationale for an E-Sail flight demonstration mission that is expected to be proposed for the 2022 time frame. The project team used an “agile” engineering approach in which E-Sail single-tether prototype designs were iteratively developed and tested to solve problems and identify design improvements. The agile approach was ideal for this low Technology Readiness Level (TRL) project because tether deployer development involved many unknowns in prototype development that could only be discovered through iterative cycles of construction and testing. Extensive modeling and simulation were accomplished for three types of tether deployment: a) Stage 1: propulsive separation with one 6U fixed b) Stage 2: propulsive spin-up with one 6U fixed c) Stage 3: propulsive spin-up with both 6Us free Simulation results were valuable for understanding the propulsive and braking forces needed for controlled tether deployment. This paper describes the evolution, insights, and test/ performance data related to the resultant single-tether two-6U E-Sail test article which has been demonstrated in a test laboratory. The development effort suggests near-term work needed to achieve a useful flight demonstration, and provides ideas for how multiple-tether deployment systems might evolve going forward. A planned next-generation E-Sail prototype will include autonomous propulsive tether deployment while monitoring tether tension, location on the floor, distance between tether ends, acceleration, velocity, and propellant used.

Tinker, Michael↗

NASA NTRS2019

Development Concepts for Mars Ascent Vehicle (MAV) Solid and Hybrid Vehicle Systems

The Advanced Concepts Office (ACO) at Marshall Space Flight Center (MSFC) has conducted ongoing studies and trades into options for both hybrid and solid vehicle systems for potential Mars Ascent Vehicle (MAV) concepts for the Jet Propulsion Laboratory (JPL). Two MAV propulsion options are being studied for use in a potential Mars Sample Retrieval (MSR) campaign. The following paper describes the current concepts for hybrid and solid propulsion vehicles for MAV as part of a potential MSR campaign, and provides an overview of the ongoing studies and trades for both hybrid and solid vehicle system concepts. Concepts and options under consideration for vehicle subsystems include reaction control system (RCS), separation, and structures will be described in terms of technology readiness level (TRL), benefit to the vehicle design, and associated risk. A hybrid propulsion system, which uses a solid fuel core and liquid oxidizer, is currently being developed by JPL with support from MSFC. This type of hybrid propulsion vehicle would allow the MAV to be more flexible at the cost of higher complexity, in contrast to the solid propulsion vehicle that is simpler, but allows less flexibility. The solid propulsion vehicle study performed by MSFC in 2018 further refined the solid propulsion system sizing as well as added definition to vehicle subsystem concepts, including the RCS, structures and configuration, interstage and separation, aerodynamics, and power/avionics. The studies were performed using an iterative concept design methodology, engaging subject matter experts from across MSFC’s propulsion and vehicle systems disciplines as well as seeking trajectory feedback from analysts at JPL.

McCollum, Lisa Tunstill↗

NASA NTRS2018

Fiber-Based Laser MOPA Transmitter Packaging for Space Environment

NASA’s Goddard Space Flight Center has been developing lidar to remotely measure CO2 and CH4 in the Earth’s atmosphere. The ultimate goal is to make space-based satellite measurements with global coverage. We are working on maturing the technology readiness of a fiber-based, 1.57-micron wavelength laser transmitter designed for use in atmospheric CO2 remote-sensing. To this end, we are building a ruggedized prototype to demonstrate the required power and performance and survive the required environment. We are building a fiber-based master oscillator power amplifier (MOPA) laser transmitter architecture. The laser is a wavelength-locked, single frequency, externally modulated DBR operating at 1.57-micron followed by erbium-doped fiber amplifiers. The last amplifier stage is a polarization-maintaining, very-large-mode-area fiber with ~1000 μm2 effective area pumped by a Raman fiber laser. The optical output is single-frequency, one microsecond pulses with >450 μJ pulse energy, 7.5 KHz repetition rate, single spatial mode, and > 20 dB polarization extinction.

Lasers and Masers↗

NASA NTRS2018

DGEN Aeropropulsion Research Turbofan (DART) Test Plans

This presentation serves as an overview of test plans for an upcoming DGEN Aeropropulsion Research Turbofan (DART) test entry at the NASA GRC AeroAcoustic Propulsion Laboratory (AAPL). The test entry includes: (1) a fan intra-stage velocity field survey, which will be compared to a Computational Fluid Dynamics (CFD) survey of DART, (2) an exploratory noise study of DART with several objectives focused on measurement projection to the far-field, source identification improvements and development of a barrier wall for isolation of various sources, (3) advancement of core/combustor noise research on DART using more extensive engine-mounted instrumentation, and (4) high-temperature pressure sensor technology-readiness-level (TRL) advancement.

Boyle, Devin K.↗