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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

Completing the development of the 12.5 kW Hall Effect Rocket with Magnetic Shielding (HERMeS)

The Hall Effect Rocket with Magnetic Shielding (HERMeS) is a 12.5 kW Hall thruster co-developed by NASA Glenn Research Center and the Jet Propulsion Laboratory. HERMeS incorporates magnetic shielding to eliminate discharge channel erosion in order to reach its design lifetime of 50 kh at specific impulses up to 3000 s. The capabilities of the HERMeS thruster technology transferred to Aerojet Rocketdyne under the Advanced Electric Propulsion System (AEPS) program are described. HERMeS hardware testing is now focused at reducing risk and supporting the qualification of the AEPS thruster. These includes a series of progressively longer wear tests, plasma characterization and modeling supporting life qualification, magnetic field optimization, and environmental testing. Initial results from AEPS thruster testing show operation consistent with the HERMeS thrusters and steady-state operation has been achieved at 600 V, 12.5 kW.

Herman, Daniel↗
NASA NTRSDate not supplied

Extended Wear Testing of the 12-kW Advanced Electric Propulsion System Engineering Test Unit Hall Thruster

This work presents a summary of the first wear test of the 12 kW Advanced Electric Propulsion System (AEPS) intended to isolate the impact of discharge current on component wear rates. Testing was led by Aerojet Rocketdyne and performed with the AEPS Engineering Test Unit 2 (ETU-2) thruster. In total, approximately 860 hours of operation were accumulated split between operating conditions of 600 V/9 kW, 600 V/11 kW, and 600 V/12 kW. Thruster performance and stability were invariant throughout the wear test for all thruster throttle conditions and shown to be equal to the values previously measured with ETU-2. Inner front pole cover erosion rates were found to be invariant to discharge current as the measurements at all three operating conditions were equal to within the empirical uncertainty. Outer front pole cover erosion rates were found to be equal for the 600 V/9 kW and 600 V/12 kW conditions with operation at 600 V/11 kW yielding elevated erosion rates. Overall, the data shows that the AEPS thruster design has a high probability of meeting lifetime and performance requirements as the design proceeds to flight production and qualification.

Jason D Frieman↗
NASA NTRS2018

Preparation for Hollow Cathode Testing for the Advanced Electric Propulsion System at NASA Glenn Research Center

NASA Glenn Research Center is performing activities to support the unique needs of hollow cathode development and testing for the Advanced Electric Propulsion System (AEPS). Three existing vacuum facilities have been outfitted as cathode test facilities, and each will serve a different role in upcoming testing. Vacuum Facility 67 is being developed to serve as a long-duration test facility for the Engineering Development Unit cathode, which is to be delivered by the AEPS contractor. It will feature a thruster-like magnetic field simulator and cold-cycle capability via a liquid nitrogen-cooled cold plate. Vacuum Facility 17 is being developed as a test facility for short- to medium-duration experiments in order to provide auxiliary support for the long-duration testing. It will feature a magnetic field simulator but not cold-cycling. Finally, Vacuum Facility 1 will be a high-pumping speed cathode development environment, and will feature an array of plasma and temperature diagnostics. In addition to the facility preparation work, a new cathode, referred to as the Mark II, has been designed. The Mark II is an evolution of the Technology Demonstration Unit cathodes that better evokes the geometry, fabrication, and construction of the forthcoming Engineering Development Unit. This cathode serves as a transition between the Technology Demonstration Unit cathodes used during early thruster development and the forthcoming Engineering Development Unit cathodes. It will be used as a means of verifying the new test facilities prior to arrival of Engineering Development Unit hardware. Details of the Mark II design and key features are presented, as well as details of future work to be performed.

Advanced Electric Propulsion System (AEPS)↗
NASA NTRSDate not supplied

Characterization Test of the 12.5-kW Advanced Electric Propulsion System Engineering Test Unit Hall Thruster

This work presents a summary of the detailed characterization testof the 12.5 kW Advanced Electric Propulsion System Engineering Test Unit 2 (AEPS ETU-2) thruster produced by Aerojet Rocketdyne. This test campaign had two major goals: to assessthe risk of design compliance with thruster requirements and providea comparison to the previously-tested NASA Hall Effect Rocket with Magnet Shielding Technology Demonstration Units (HERMeS TDUs) from which the AEPS ETU design was derived.

AEPS↗
NASA NTRSDate not supplied

NASA Progress on the Development and Qualification of a 12-kW Hall-Effect, Solar Electric Propulsion Thruster

The National Aeronautics and Space Administration (NASA) continues to evolve the human exploration approach for beyond low-Earth orbit and in a manner involving international, academic, and industry partners. The center of this approach is NASA’s Gateway program that will establish a permanent human presence in lunar orbit for human cislunar science, operations, and lunar surface access to eventually land the next American astronauts on the south pole of the Moon. In support of the effort, NASA’s Space Technology Mission Directorate (STMD) began a project to increase the state of the art for the Hall-Effect Solar Electric Propulsion (SEP) technology. The resulting Advanced Electric Propulsion System (AEPS) project has developed a 12 kW Hall-effect thruster in support of the Gateway program. The project is managed by the NASA Glenn Research Center (GRC), supported by the NASA Jet Propulsion Laboratory (JPL) with development, qualification & flight hardware all supplied by L3 Harris Aerojet Rocketdyne (AR). Development of the 12-kW Hall thruster electric propulsion system began with maturation of the Hall Effect Rocket with Magnetic Shielding (HERMeS) Technology Demonstration Units (TDUs). The technology development was then transitioned to AR via the AEPS contract, which built and tested two Engineering Test Unit (ETU) thrusters and multiple critical components. The project transitioned to the production of the three flight thrusters and entered qualification testing at the component and thruster levels.

Electric Propulsion↗
NASA NTRSDate not supplied

NASA Progress on the Development and Qualification of a 12-kW Hall-Effect, Solar Electric Propulsion Thruster

The National Aeronautics and Space Administration (NASA) continues to evolve the human exploration approach for beyond low-Earth orbit and in a manner involving international, academic, and industry partners. The center of this approach is NASA’s Gateway program that will establish a permanent human presence in lunar orbit for human cislunar science, operations, and lunar surface access to eventually land the next American astronauts on the south pole of the Moon. In support of the effort, NASA’s Space Technology Mission Directorate (STMD) began a project to increase the state of the art for the Hall-Effect Solar Electric Propulsion (SEP) technology. The resulting Advanced Electric Propulsion System (AEPS) project has developed a 12 kW Hall-effect thruster in support of the Gateway program. The project is managed by the NASA Glenn Research Center (GRC), supported by the NASA Jet Propulsion Laboratory (JPL) with development, qualification & flight hardware all supplied by L3 Harris Aerojet Rocketdyne (AR). Development of the 12-kW Hall thruster electric propulsion system began with maturation of the Hall Effect Rocket with Magnetic Shielding (HERMeS) Technology Demonstration Units (TDUs). The technology development was then transitioned to AR via the AEPS contract, which built and tested two Engineering Test Unit (ETU) thrusters and multiple critical components. The project transitioned to the production of the three flight thrusters and entered qualification testing at the component and thruster levels.

Electric Propulsion↗
NASA NTRS1972

Advanced extravehicular protective systems study, volume 2

The results of the subsystem studies are presented. Initial identification and evaluation of candidate subsystem concepts in the area of thermal control, humidity control, CO2 control/O2 supply, contaminant control and power supply are discussed. The candidate concepts that were judged to be obviously noncompetitive were deleted from further consideration and the remaining candidate concepts were carried into the go/no go evaluation. A detailed parametric analysis of each of the thermal/humidity control and CO2 control/O2 supply subsystem concepts which passed the go/no go evaluation is described. Based upon the results of the parametric analyses, primary and secondary evaluations of the remaining candidate concepts were conducted. These results and the subsystem recommendations emanating from these results are discussed. In addition, the parametric analyses of the recommended subsystem concepts were updated to reflect the final AEPS specification requirements. A detailed discussion regarding the selection of the AEPS operating pressure level is presented.

Sutton, J. G.↗
NASA NTRS2018

Preparation for Hollow Cathode Testing for the Advanced Electric Propulsion System at NASA Glenn Research Center

NASA Glenn Research Center is performing activities to support the unique needs of hollow cathode development and testing for the Advanced Electric Propulsion System (AEPS). Three existing vacuum facilities have been outfitted as cathode test facilities, and each will serve a different role in upcoming testing. Vacuum Facility 67 is being developed to serve as a long-duration test facility for the Engineering Development Unit cathode, which is to be delivered by the AEPS contractor. It will feature a thruster-like magnetic field simulator and cold-cycle capability via a liquid nitrogen-cooled cold plate. Vacuum Facility 17 is being developed as a test facility for short- to medium-duration experiments in order to provide auxiliary support for the long-duration testing. It will feature a magnetic field simulator but not cold-cycling. Finally, Vacuum Facility 1 will be a high-pumping speed cathode development environment, and will feature an array of plasma and temperature diagnostics. In addition to the facility preparation work, a new cathode, referred to as the Mark II, has been designed. The Mark II is an evolution of the Technology Demonstration Unit cathodes that better evokes the geometry, fabrication, and construction of the forthcoming Engineering Development Unit. This cathode serves as a transition between the Technology Demonstration Unit cathodes used during early thruster development and the forthcoming Engineering Development Unit cathodes. It will be used as a means of verifying the new test facilities prior to arrival of Engineering Development Unit hardware. Details of the Mark II design and key features are presented, as well as details of future work to be performed.

Hall, Scott J.↗
NASA NTRS2018

Preparation for Hollow Cathode Testing for the Advanced Electric Propulsion System at NASA Glenn Research Center

NASA Glenn Research Center is performing activities to support the unique needs of hollow cathode development and testing for the Advanced Electric Propulsion System (AEPS). Three existing vacuum facilities have been outfitted as cathode test facilities, and each will serve a different role in upcoming testing. Vacuum Facility 67 is being developed to serve as a long-duration test facility for the Engineering Development Unit cathode, which is to be delivered by the AEPS contractor. It will feature a thruster-like magnetic field simulator and cold-cycle capability via a liquid nitrogen-cooled cold plate. Vacuum Facility 17 is being developed as a test facility for short- to medium-duration experiments in order to provide auxiliary support for the long-duration testing. It will feature a magnetic field simulator but not cold-cycling. Finally, Vacuum Facility 1 will be a high-pumping speed cathode development environment, and will feature an array of plasma and temperature diagnostics. In addition to the facility preparation work, a new cathode, referred to as the Mark II, has been designed. The Mark II is an evolution of the Technology Demonstration Unit cathodes that better evokes the geometry, fabrication, and construction of the forthcoming Engineering Development Unit. This cathode serves as a transition between the Technology Demonstration Unit cathodes used during early thruster development and the forthcoming Engineering Development Unit cathodes. It will be used as a means of verifying the new test facilities prior to arrival of Engineering Development Unit hardware. Details of the Mark II design and key features are presented, as well as details of future work to be performed.

Hall, Scott J.↗
NASA NTRS2019

The Application of Advanced Electric Propulsion on the NASA Power and Propulsion Element (PPE)

NASA is charged with landing the first American woman and next American man on the South Pole of the Moon by 2024. To meet this challenge, NASA's Gateway will develop and deploy critical infrastructure required for operations on the lunar surface and that enables a sustained presence on and around the moon. NASA's Power and Propulsion Element (PPE), the first planned element of NASA's cis-lunar Gateway, leverages prior and ongoing NASA and U.S. industry investments in high-power, long-life solar electric propulsion technology investments. NASA awarded a PPE contract to Maxar Technologies to demonstrate a 2,500 kg xenon capacity, 50 kW-class SEP spacecraft that meets Gateway's needs, aligns with industry's heritage spacecraft buses, and allows extensibility for NASA's Mars exploration goals. Maxar's PPE concept design, is based directly on their high heritage, modular, highly reliable 1300-series bus architecture. The electric propulsion system features two 13 kW Advanced Electric Propulsion (AEPS) strings from Aerojet Rocketdyne and a Maxar-developed system comprised of four Busek 6 kW Hall-effect thrusters mounted in pairs on large range of motion pointing arms with four 6 kW-class, SPT-140-based PPUs. NASA is continuing to develop the 13 kW AEPS system through a contract with Aerojet Rocketdyne. In addition to the flight demonstration of an advanced electric propulsion system on PPE, a government-furnished plasma diagnostics package is planned to assess on-orbit performance characteristics and vehicle interactions. The paper will present overviews of NASA's Gateway and the PPE Project, the Maxar ion propulsion subsystem, the status of the two electric propulsion system developments, and the implementation of the plasma diagnostics package on the Maxar PPE spacecraft. The project is currently heading into SRR, with the propulsion build scheduled for 2021, and launch in 2022.

Herman, Daniel A.↗
NASA NTRSDate not supplied

12.5kW Advanced Electric Propulsion System Thruster Development Testing

Since 2012, NASA has been developing the12.5kW Hall Effect Rocket with Magnetic Shielding (HERMeS)thruster to serve the need for deep space propulsion. Aerojet Rocketdyne (AR)is developing the HERMeS Hall Current Thruster (HCT)into a flight capable design through the Advanced Electric Propulsion System (AEPS) program. In execution of this program, Aerojet Rocketdyne has designed, built and begun test of two Engineering Test Unit (ETU)HCTs, designated ETU-1 and ETU-2. This paper presents some of the preliminary results from theETU-1 thruster and draws comparisons to previous HERMeS Technology Demonstration Units (TDUs)and theETU-2 characterization unit. The ETU-1 thruster serves to evaluate the ETU design against dynamic and thermal environments while ETU-2 undergoes operational characterization and wear testing. The thruster has been exposed to acceptance and qualification-level vibration and shock testing and has undergone acceptance and characterization hot-firing to evaluate thruster performance after exposure to dynamic environments. The results have demonstrated that the dynamic environments have not had an adverse effect on performance and demonstrated that stability and operating characteristics remain unaffected. Together, ETU-1 and ETU-2 HCTs have demonstrated operating performance and characteristics in-family with each other and with the NASA HERMeS Technology Demonstration Units.

AEPS↗
NASA NTRS1987

Effects of combining vertical and horizontal information into a primary flight display

A ground-based aircraft simulation study was conducted to determine the effects of combining vertical and horizontal flight information into a single display. Two display configurations were used in this study. The first configuration consisted of a Primary Flight Display (PFD) format and a Horizontal Situation Display (HSD) with the PFD displayed conventionally above the HSD. For the second display configuration, the HSD format was combined with the PFD format. Four subjects participated in this study. Data were collected on performance parameters, pilot-control inputs, auditory evoked response parameters (AEP), oculometer measurements (eye-scan), and heart rate. Subjective pilot opinion was gathered through questionnaire data and scorings for both the Subjective Workload Assessment Technique (SWAT) and the NASA Task Load Index (NASA-TLX). The results of this study showed that, from a performance and subjective standpoint, the combined configuration was better than the separate configuration. Additionally, both the eye-transition and eye-dwell times for the separate HSD were notably higher than expected, with a 46% increase in available visual time when going from double to single display configuration.

Abbott, Terence S.↗
NASA NTRS2017

Hybrid-PIC Simulation of Backsputtered Carbon Transport in the Near-Field Plume of a Hall Thruster

Magnetic shielding has eliminated boron nitride erosion as the life limiting mechanism in a Hall thruster but has resulted in erosion of the front magnetic field pole pieces. Recent experiments show that the erosion of graphite pole covers, which are added to protect the magnetic field pole pieces, causes carbon to redeposit on other surfaces, such as boron nitride discharge channel and cathode keeper surfaces. As a part of the risk-reduction activities for AEPS thruster development, this study models transport of backsputtered carbon from the graphite front pole covers and vacuum facility walls. Fluxes, energy distributions, and redeposition rates of backsputtered carbon on the anode, discharge channel, and graphite cathode keeper surfaces are predicted.

Choi, Maria↗
NASA NTRSDate not supplied

Wear Test of the 12.5-kW Advanced Electric Propulsion System Engineering Test Unit Hall Thruster

This work presents a summary of the first wear test of the 12.5 kW Advanced Electric Propulsion System Engineering Test Unit 2 (AEPS ETU-2) thruster produced by Aerojet Rocketdyne. The ETU-2 Wear Test accumulated approximately 730 hours of operation split between the nominal 600 V/12.5 kW condition and the 300 V/6.25 kW condition previously identified as the worst-case erosion condition.

Jason D. Frieman↗
NASA NTRSDate not supplied

Development and Qualification Status of the Electric Propulsion Systems for the NASA PPE Mission and Gateway Program

NASA is charged with landing the first American woman and next American man on the South Pole of the Moon and establishing sustainable lunar exploration by the end of the decade. To meet this challenge, NASA’s Gateway will develop and deploy critical infrastructure required for operations on the lunar surface and that enables a sustained presence on and around the moon. NASA’s Power and Propulsion Element (PPE), the first planned element of NASA’s cis-lunar Gateway, leverages prior and ongoing NASA and U.S. industry investments in high-power, long-life solar electric propulsion technology investments. NASA awarded a PPE contract to Maxar Technologies to provide a 50 kW-class SEP spacecraft that meets Gateway’s needs, aligns with industry’s heritage spacecraft buses, and allows extensibility for NASA’s Mars exploration goals. Maxar’s PPE concept design, is based on their high heritage, modular, and highly reliable 1300-series bus architecture. The electric propulsion system features three 12 kW Advanced Electric Propulsion (AEPS) thrusters from Aerojet Rocketdyne and four BHT-6000 thrusters from Busek. Maxar-provided power electronics and xenon flow controllers from Moog are utilized in both the 12kW and 6kW electric propulsion strings on the spacecraft. The paper will present overviews of NASA’s Gateway and the PPE Project, status of the development and qualification activities for the two electric propulsion system, and the planned implementation of PPE electric propulsion system as keystone of NASA’s Gateway. The PPE spacecraft is currently heading into the Critical Design Review, with the qualification and flight electric propulsion hardware fabrication already initiated and significant progress being made toward planned qualifications in support of the planned PPE spacecraft co-manifest launch in 2024.

Electric Propulsion↗
NASA NTRSDate not supplied

Development and Qualification Status of the Electric Propulsion Systems for the NASA PPE Mission and Gateway Program

NASA is charged with landing the first American woman and next American man on the South Pole of the Moon and establishing sustainable lunar exploration by the end of the decade. To meet this challenge, NASA’s Gateway will develop and deploy critical infrastructure required for operations on the lunar surface and that enables a sustained presence on and around the moon. NASA’s Power and Propulsion Element (PPE), the first planned element of NASA’s cis-lunar Gateway, leverages prior and ongoing NASA and U.S. industry investments in high-power, long-life solar electric propulsion technology investments. NASA awarded a PPE contract to Maxar Technologies to provide a 50 kW-class SEP spacecraft that meets Gateway’s needs, aligns with industry’s heritage spacecraft buses, and allows extensibility for NASA’s Mars exploration goals. Maxar’s PPE concept design, is based on their high heritage, modular, and highly reliable 1300-series bus architecture. The electric propulsion system features three 12 kW Advanced Electric Propulsion (AEPS) thrusters from Aerojet Rocketdyne and four BHT-6000 thrusters from Busek. Maxar-provided power electronics and xenon flow controllers from Moog are utilized in both the 12kW and 6kW electric propulsion strings on the spacecraft. The paper will present overviews of NASA’s Gateway and the PPE Project, status of the development and qualification activities for the two electric propulsion system, and the planned implementation of PPE electric propulsion system as keystone of NASA’s Gateway. The PPE spacecraft is currently heading into the Critical Design Review, with the qualification and flight electric propulsion hardware fabrication already initiated and significant progress being made toward planned qualifications in support of the planned PPE spacecraft co-manifest launch in 2024.

Electric Propulsion↗
NASA NTRS2022

LIF Testing of ETU-2 in VF-5

A visualization of the experimental setup for the Laser-Induced Fluorescence (LIF) diagnostic system applied to AEPS Engineering Test Unit 2 (ETU-2) in the Electric Propulsion and Power Laboratory's (EPPL) Vacuum Facility 5 (VF-5)

LIF↗
NASA NTRSDate not supplied

NASA Gateway Refueling Architecture and Concept of Operation

The Lunar Gateway is a deep space orbiting outpost being developed by NASA in partnership with ESA and other domestic and international partners. It is a critical component of NASA’s Artemis program supporting long-term human exploration of the moon and is designed to be refueled, requiring the on-orbit transfer of propellants. The first two modules of Gateway to be launched will be the Power and Propulsion Element (PPE) and the Habitation and Logistics Outpost (HALO). The PPE contains the bipropellant chemical and electrical propulsion systems that will provide attitude control and orbit raising capability for Gateway. The reaction control system (RCS) utilizes monomethylhydrazine (MMH) and mixed oxides of nitrogen-3 (MON-3) as the fuel and oxidizer, respectively. Helium is used as a pressurant. The Advanced Electric Propulsion Systems (AEPS) and Busek hall thrusters that comprise the solar electric propulsion (SEP) system use xenon as the propellent. The ESPRIT Refueling Module, provided by ESA, will supply the propellant refueling function to Gateway’s propulsion systems. On-orbit refueling is a complex, technically challenging operation that is key to enabling sustainable crewed Lunar and Martian exploration. Numerous systems may be involved in the refueling operation. Also numerous systems are required to enable the successful ability for Gateway to refuel such as, SEP, RCS, Structure & Mechanisms (S&M), Guidance, Navigation and Control (GNC), Thermal, Software, Vehicle System Manager (VSM), Flight Ops, Extra Vehicular Robotics (EVR), Communication and Tracking (C&T), Avionics, and more. This paper will detail the design architecture, concept of operations, and challenges associated with the Gateway refueling system. The methodologies used in Gateway will be compared to those implemented in OSAM-1 and the best practices documented by AIAA and CONFERS (Consortium For Execution Of Rendezvous And Servicing Operations).

Brandie L. Rhodes↗