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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 1,657 records · Page 92
All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

Enabling Additive Manufacturing Technologies for Advanced Aero Propulsion Materials & Components

Additive manufacturing (AM) technologies are enabling for advanced high performance, propulsion component designs in electric motors1-2 and turbine engine systems in future electrified aircraft. AM offers significant benefits over conventional manufacturing to fabricate components that are more compact, lighter weight, geometrically complex, innovatively cooled, integrated, multi-material, and multifunctional. For turbine engine applications, silicon carbide (SiC) based composites are being pursued using binder jetting and laminated object manufacturing (LOM) for components such as shrouds, vanes, and recuperators. For electric motor applications, additive processes are being applied toward optimized component designs to include the housing, rotor, and stators with 3-D printing and wire imbedded coils and with direct printed 3-phase coils. The electrical conductivity of silver conductor coils optimized by evaluating alternate sintering methods and additions of graphene and carbon nanostructures will be presented. Potential benefits of new electric motor components in improving temperature capability, efficiency, and power density for reductions in energy consumption and emissions will be discussed.

Halbig, Michael C.↗
NASA NTRS2019

CAMIEM: Compact Additively Manufactured Innovative Electric Motor

New manufacturing methods are needed to obtain innovative electric motor designs that have much higher power densities and/or efficiencies compared to the current state-of-the-art. Additive manufacturing offers the potential to radically change motor designs so that they have compact designs, multi-material components, innovative cooling, and optimally designed and manufactured components. New component designs enabled by additive manufacturing technologies have been designed and were fabricated to include the housing, rotors, stator cooling ring, a direct printed stator, and a wire embedded stator. The new components were integrated into the motor and tested evaluate the performance gains in comparison to the baseline electric motor configuration. Partners on the sub-project include NASA GRC, NASA LaRC, NASA AFRC, LaunchPoint Technologies, and the University of Texas El Paso.

Halbig, Michael C.↗
NASA NTRSDate not supplied

TPSAS-NF1676L-34884-DND

New manufacturing methods are needed to enable innovative electric motor designs that have much higher power densities and/or efficiencies compared to the current state-of-the-art. Additive manufacturing (AM) offers the potential to radically change motor designs so that they have compact designs, multi-material components, innovative cooling, and optimally designed and manufactured components.

Michael Halbig↗
NASA NTRSDate not supplied

Fabrication of Extruded Polyphenylsulfone – Boron Nitride Composite Tapes

Polyphenylsulfone (PPSU) is a high-temperature, chemically resistant thermoplastic with high impact resistance that is often used in interior aircraft cabin components, medical devices, and membranes. The aforementioned properties have led to interest investigating PPSU’s compatibility with hexagonal boron nitride (hBN) platelets as a thermally conductive, electrical composite insulator for high power-density electric machines. Preliminary trials extruding PPSU-hBN composite tapes showed promising dielectric properties and higher thermal conductivity as a function of hBN concentration compared to their neat analog. On the other hand, only few studies have reported on the extrusion process and resulting thermo-mechanical properties for PPSU and its composites made with chopped fiber reinforcement or fillers, none of which containing boron nitride filler. Prospects may exist for this type of material to be incorporated into extrusion-based additive manufacturing techniques to print other composites bearing unique properties useful for aerospace. Loading levels with up to approximately 23 wt% were achieved using micro-size BN platelets without observing any significant affects to PPSU’s glass-transition temperature. This work includes a description of the rheological properties of PPSU, the extrusion parameters for mixing and compounding the PPSU-hBN composite tapes, and the thermal and thermo-mechanical properties of PPSU-hBN composites.

polyphenylsulfone↗
NASA NTRS2020

A Rapid change in x-ray variability and a jet ejection in the black hole transient MAXI J1820+070

We present Neutron Star Interior Composition Explorer X-ray and Arcminute Microkelvin Imager Large Array radio observations of a rapid hard-to-soft state transition in the black hole X-ray transient MAXI J1820+070. During the transition from the hard state to the soft state a switch between two particular types of quasiperiodic oscillations (QPOs) was seen in the X-ray power density spectra, from type-C to type-B, along with a drop in the strength of the broadband X-ray variability and a brief flare in the 7–12 keV band. Soon after this switch (∼2–2.5 hr) a strong radio flare was observed that corresponded to the launch of superluminal ejecta. Although hints of a connection between QPO transitions and radio flares have been seen in other black hole X-ray transients, our observations constitute the strongest observational evidence to date for a link between the appearance of type-B QPOs and the launch of discrete jet ejections.

Jeroen Homan↗
NASA NTRS2020

NICER Observations Reveal that the X-ray Transient MAXI J1348-630 is a Black Hole X-ray Binary

We studied the outburst evolution and timing properties of the recently discovered X-ray transient MAXI J1348−630 as observed with NICER. We produced the fundamental diagrams commonly used to trace the spectral evolution, and power density spectra to study the fast X-ray variability. The main outburst evolution of MAXI J1348−630 is similar to that commonly observed in blackhole transients. The source evolved from the hard state (HS), through hard- and soft-intermediate states, into the soft state in the outburst rise, and back to the HS in reverse during the outburst decay. At the end of the outburst, MAXI J1348−630 underwent two reflares with peak fluxes approximately one and two orders of magnitude fainter than the main outburst, respectively. During the reflares, the source remained in the HS only, without undergoing any state transitions, which is similar to the so-called ‘failed outbursts’. Different types of quasi-periodic oscillations (QPOs) are observed at different phases of the outburst. Based on our spectral-timing results, we conclude that MAXI J1348−630 is a black hole candidate.

L Zhang↗
NASA NTRSDate not supplied

Fabrication of Extruded Polyphenylsulfone – Boron Nitride Composite Tapes

Polyphenylsulfone (PPSU) is a high-temperature, chemically resistant thermoplastic with high impact resistance that is often used in interior aircraft cabin components, medical devices, and membranes. The aforementioned properties have led to interest investigating PPSU’s compatibility with hexagonal boron nitride (hBN) platelets as a thermally conductive, electrical composite insulator for high power-density electric machines. Preliminary trials extruding PPSU-hBN composite tapes showed promising dielectric properties and higher thermal conductivity as a function of hBN concentration compared to their neat analog. On the other hand, only few studies have reported on the extrusion process and resulting thermo-mechanical properties for PPSU and its composites made with chopped fiber reinforcement or fillers, none of which contained boron nitride filler. Prospects may exist for this type of material to be incorporated into extrusion-based additive manufacturing techniques to print other composites bearing unique properties useful for aerospace. Loading levels with up to approximately 23 wt% were achieved using micro-size BN platelets without observing any significant affects to PPSU’s glass-transition temperature. This work includes a description of the rheological properties of PPSU, the extrusion parameters for mixing and compounding the PPSU-hBN composite tapes, and the thermal and thermo-mechanical properties of PPSU-hBN composites.

Tiffany Williams↗
NASA NTRSDate not supplied

Potential of Materials to Impact Megawatt-Scale Electric Machines

High specific power density, megawatt-scale electric machines (motors and generators) are needed to enable megawatt-scale electric aircraft propulsion systems for single isle aircraft. Thermally insulating electrical insulation materials in the stator windings limits the ability to thermally manage the heat produced in these machines. Polymer-ceramic composites along with novel processing techniques offer viable options to improve the thermal conductivity of the electrical insulation system. This paper outlines current National Aeronautics and Space Administration’s Glenn Research Center efforts of developing several polymer-ceramic systems and processing techniques as they relate to electric machine insulation (including potting). There is also analysis of how these factors relate to machine performance.

electric macnhine↗
NASA NTRSDate not supplied

MAB Phase Ceramics for Lunar Applications

During the ten-week internship my work focused on designing characterization protocol for 3D printed MAB phase ceramics on steel and Tiplates. I was mentored by Dr. Samuel Hocker of NASA and advised by Dr. Gupta from University of North Dakota. I also collaborated with Mackenzie Short from the University of North Dakota. The characterization protocol was divided into following steps; initially, we performed visual inspection of the plates. During this process, the coatings which spalled or delaminated were discarded for further evaluation. During the next step, we performed optical microscopy to discern and document surface features and porosities of the samples. We also noted some decomposition under the optical microscope as well. Thereafter, profilometry analysis was performed to understand the effect of power density on the surface roughness. Due to the deposited powder over the samples, the profilometry was inconclusive. We then cleaned the samples on the steel plate using ethanol and cotton swabs to wipe up the loose powder covering the samples. Detailed SEM analysis was then performed on the cleaned specimens. In parallel, the 3D printed samples on the Tiplate were cleaned by using an ultrasonic bath for 1h. Optical imaging showed that this cleaning process was more effective for cleaning except that small cracks propagated through the layered ceramics. The profilometry data gathered on the titanium plate after cleaning was more conclusive. The SEM data on the steel plate showed that there is decomposition at all wattages although at 100 W the extent of decomposition was lower. We are planning to characterize the steel samples after cleaning in ultrasonic bath for 5-10 min to minimize cracking during the cleaning process. In addition, we are also planning to study the fractured surface by SEM analysis.

Additive Manufacturing, Laser Powder Bed Fusion, S↗
NASA NTRSDate not supplied

Overview of Fuel System Options for Nuclear Thermal Propulsion

An in-space propulsion technology, nuclear thermal propulsion (NTP) has the potential to enable faster interplanetary transit times compared to traditional chemical propulsion methods due to its capacity for high specific impulse (900+ s) and thrust (~10 – 100 klbf). Because of these performance attributes, NTP is currently one of several advanced propulsion technologies currently under consideration by the National Aeronautics and Space Administration (NASA) for future crewed Mars missions. The performance of NTP systems is directly contingent upon the development of a robust fuel form capable of withstanding high-power densities and operation in a hydrogen environment at temperatures in excess of 2500 K. This presentation will overview development needs for fuels in NTP systems, historic and current NTP fuel system options, and their remaining challenges prior to successful implementation.

nuclear thermal propulsion↗
NASA NTRS2021

NICER Observations of the Black Hole Candidate MAXI J0637-430 during the 2019-2020 Outburst

We present detailed timing and spectral studies of the black hole candidate MAXI J0637–430 during its 2019–2020 outburst using observations with the Neutron Star Interior Composition Explorer (NICER)and the Neil Gehrels Swift Observatory. We find that the source evolves through the soft-intermediate, high-soft, hard-intermediate, and low-hard states during the outburst. No evidence of quasi-periodic oscillations is found in the power-density spectra of the source. Weak variability with fraction alarms amplitude<5 per cent is found in the softer spectral states. In the hard-intermediate and hard states, high variability with the fractional rms amplitude of>20 per cent is observed. The 0.7–10 keV spectra with NICER are studied with a combined disc-black-body and nth comp model along with the interstellar absorption. The temperature of the disc is estimated to be 0.6 keV in the rising phase and decreased slowly to 0.1 keV in the declining phase. The disc component was not detectable or absent during the low-hard state. From the state-transition luminosity and the inner edge of the accretion flow, we estimate the mass of the black hole to be in the range of 5–12 M, assuming the source distance of d<10 kpc.

Arghajit Jana↗
NASA NTRSDate not supplied

Solid-state Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) for Electric Aircraft

All-electric vertical take-off and landing vehicles (eVTOL) for urban air mobility (UAM) concepts face numerous challenging technical barriers before their introduction into the consumer marketplace. The primary barrier to overcome is developing an energy storage system capable of meeting the rigorous aerospace safety and performance criteria. The performance metrics for eVTOL vehicles are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for safe operation of commercial electric aerovehicles. The SABERS concept proposes a battery that meets the key performance criteria through development of a solid-state architecture battery utilizing high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. This hybrid cathode will be developed by implementing NASA patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte will be used as a safe, non-flammable replacement to the highly flammable liquid organic electrolytes currently used in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed into a serial stacking configuration to enable dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C which provides the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. This presentation will demonstrate a feasible path for solid-state cells that possess a specific energy of greater than 400 Wh/kg to enable electric aircraft.

Urban Air Mobility (UAM) Vehicles↗
NASA NTRSDate not supplied

Solid-state Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) Beyond Li-Ion: Technology to Enable Sustainable Electric Aviation

All-electric vertical take-off and landing vehicles (eVTOL) for urban air mobility (UAM) concepts face numerous challenging technical barriers before their introduction into the consumer marketplace. The primary barrier to overcome is developing an energy storage system capable of meeting the rigorous aerospace safety and performance criteria. The performance metrics for eVTOL vehicles are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for safe operation of commercial electric aerovehicles. The SABERS concept proposes a battery that meets the key performance criteria through development of a solid-state architecture battery utilizing high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. This hybrid cathode will be developed by implementing NASA patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte will be used as a safe, non-flammable replacement to the highly flammable liquid organic electrolytes currently used in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed into a serial stacking configuration to enable dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C which provides the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. This presentation will demonstrate a feasible path for solid-state cells that possess a specific energy of greater than 400 Wh/kg to enable electric aircraft.

Urban Air Mobility (UAM) Vehicles↗
NASA NTRSDate not supplied

Additively Manufactured Ink-based Cell Batteries for Flexible Conformational Applications

With the rise of additively manufactured electronics, the importance of thin, flexible printed batteries has increased for shape-conformal electronics. Traditionally, battery cells such as industry-standard lithium-ion batteries, have been rigid and therefore unable to conform to time-variant surfaces such as smart cards/RFID devices, disposable battery-powered skin patches, foldable electronic devices, and IoT nodes. Aligned with the effort to advance technologies on printed electronics for habitat systems and advanced manufacturing, this proof-of-concept will focus on printing a 50 mAh Zn-Ag battery implementing a DIW Technique. After prototype manufacturing, electrical and environmental testing on the flexible battery cell will be conducted to the evaluate energy and power density over 50 charge cycles under standard atmosphere conditions. The project aims to provide PCB designers, fabricators, and assemblers an integrated battery package to eliminate external batteries, external wiring and connectors, and conformational complexity. Potential end uses of the printed battery process will be within Martian and lunar habitat systems, Gateway, and surface vehicles, or aerial robots where space and geometry is a restriction.

Printed Electronics↗
NASA NTRS2023

Solid-State Architecture Batteries for Enhanced Rechargeability and Safety (SABERS): Advanced Battery Technology for Sustainable Aviation

All-electric vertical take-off and landing vehicles (eVTOL) for urban air mobility (UAM) concepts face numerous challenging technical barriers before their introduction into the consumer marketplace. The primary barrier to overcome is developing an energy storage system capable of meeting the rigorous aerospace safety and performance criteria. The performance metrics for eVTOL vehicles are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for safe operation of commercial electric aerovehicles. The SABERS concept proposes a battery that meets the key performance criteria through development of a solid-state architecture battery utilizing high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. This hybrid cathode will be developed by implementing NASA patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte will be used as a safe, non-flammable replacement to the highly flammable liquid organic electrolytes currently used in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed into a serial stacking configuration to enable dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C which provides the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. This presentation will demonstrate a feasible path for solid-state cells that possess a specific energy of greater than 400 Wh/kg to enable electric aircraft. The presentation will also explore novel materials and computational models used to achieve all solid-state cells that operate safely at very high temperatures and specific energies. The cells can withstand damage while operating without an increase in temperature or spontaneous ignition.

Urban Air Mobility (UAM) Vehicles↗
NASA NTRSDate not supplied

Solid-state Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) Beyond Li-Ion: Technology to Enable Sustainable Electric Aviation

All-electric and hybrid electric aerovehicle concepts face numerous technical barriers prior to their introduction into the consumer marketplace in order to meet sustainable aviation goals. One of the primary barriers to overcome is developing an energy dense storage system capable of meeting the rigorous aerospace safety and performance criteria. Additionally, the electric aviation market requires that the batteries be fabricated in a sustainable manner with materials that are readily available and abundant within the U.S. to ensure there are no supply chain issues during manufacturing. The performance metrics to enable electric aviation are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for safe operation of commercial electric aerovehicles. The SABERS concept proposes a battery that meets the key performance criteria through development of a solid-state architecture battery utilizing high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. The hybrid cathode has been developed by implementing NASA patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte has been used as a safe, non-flammable replacement to the highly flammable liquid organic electrolytes currently used in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed into a serial stacking configuration to enable dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C which provides the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. This poster summarizes recent results from battery component optimization to scale-up production of full SABERS pouch cells.

Urban Air Mobility (UAM) Vehicles↗
NASA NTRS2024

X-57 Maxwell High Lift Motor Controller Electromagnetic Interference Test Results

During research and development for NASA’s X-57 Maxwell all-electric aircraft project, the efficiency and power density requirements of its electric propulsion subsystem components were met, but aspects of integrating its powertrain subsystems proved problematic. Electromagnetic interference (EMI) from the cruise motor controller (CMC) was a significant challenge for the project. This problem was exacerbated by the lack of EMI requirements imposed on subsystem powertrain components. This report presents the results of EMI testing of the X-57 high lift motor controller (HLMC) at the NASA Glenn Research Center’s EMI Laboratory. For reference, the conducted emissions are compared to DO–160G and MIL–STD–61G conducted emissions limits. After the EMI test, mitigation of the conducted emissions using lightweight EMI chokes produced at NASA Glenn was evaluated using the Fast Fourier Transform (FFT) capability of an oscilloscope in the hardware development laboratory. This process can contribute to the rapid prototyping of electric powertrain components and EMI filters and improve the likelihood of successful EMI qualification at the component and system levels.

Silicon carbide↗