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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 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Phase-Free Orbital Element Model Designed to Enable Rapid Assessment of Eclipse and Radiation Profiles for Low-Thrust Spiral Transfers Around the Earth

The Gateway Power and Propulsion Element (PPE) will be the first low-thrust solar electric ion propulsion mission to transfer from a highly elliptical Earth-bound orbit to a southern near-rectilinear halo orbit (NRHO) at the Earth-Moon L2 point. Due to the low thrust nature of the transfer orbit, it is desirable to locate viable trajectories that minimize the time spent in the Van Allen radiation belts to reduce solar array degradation and keep radiation dosages below design limits. In addition to radiation, low thrust trajectories which spiral around the Earth will pass through at least one or more seasons of Earth eclipses. The solar electric propulsion system relies on sunlight to generate the power necessary to operate the ion thrusters. Therefore, it is advantageous to find trajectories which also minimize the amount of time spent in eclipse and avoid excessive battery draw-down periods. We present an analytical method which rapidly approximates low-thrust spiral trajectories, fit to high-fidelity simulated data and parameterized to allow for changes in vehicle thrust characteristics, that is post-processed to determine eclipse profiles and time spent in the belts using a novel approach that estimates the geometry of the belts using a first-order dipole approximation of the Earth’s magnetic field. This method can be used to find satisfactory launch dates and orbit orientations that can serve as initial guesses when optimizing such missions in high-fidelity software.

low thrust trajectory design↗
NASA NTRS1999

The Mars Development of a Micro-Isolation Valve

A feasibility investigation for a newly proposed microfabricated, normally-closed isolation valve was initiated. The micro-isolation valve is silicon based and relies on the principle of melting a silicon plug, opening an otherwise sealed flow passage. This valve may thus serve a similar role as a conventional pyrovalve and is intended for use in micropropulsion systems onboard future microspacecraft, having wet masses of no more than 10-20 kg, as well as in larger scale propulsion systems having only low flow rate requirements, such as ion propulsion or Hall thruster systems. Two key feasibility issues - melting of the plug and pressure handling capability - were addressed. Thermal finite element modeling showed that valves with plugs having widths between 10 and 50 gm have power requirements of only 10 . 30 Watts to open over a duration of 0.5 ms or less. Valve chips featuring 5 0 micron plugs were burst pressure tested and reached maximum pressure values o f 2900 psig (19.7 Mpa).

Mueller, Juergen↗
NASA NTRS1976

Electron bombardment propulsion system characteristics for large space systems

The results of an anlaysis of electron bombardment ion propulsion systems for use in the transportation and on-orbit operations of large space systems are presented. Using baseline technology from the ongoing primary propulsion program and other sources, preliminary estimates of the expected characteristics of key system elements such as thrusters and propellant storage systems were performed. Projections of expected thruster performance on argon are presented based on identified constraints which limit the achievable thrust and/or power density of bombardment thrusters. System characteristics are then evaluated as a function of thruster diameter and specific impulse.

Byers, D. C.↗
NASA NTRS1999

Thermal Environmental Testing of NSTAR Engineering Model Ion Thrusters

NASA's New Millenium program will fly a xenon ion propulsion system on the Deep Space 1 Mission. Tests were conducted under NASA's Solar Electric Propulsion Technology Applications Readiness (NSTAR) Program with 3 different engineering model ion thrusters to determine thruster thermal characteristics over the NSTAR operating range in a variety of thermal environments. A liquid nitrogen-cooled shroud was used to cold-soak the thruster to -120 C. Initial tests were performed prior to a mature spacecraft design. Those results and the final, severe, requirements mandated by the spacecraft led to several changes to the basic thermal design. These changes were incorporated into a final design and tested over a wide range of environmental conditions.

Rawlin, Vincent K.↗
NASA NTRS1976

Electron bombardment propulsion system characteristics for large space systems

Presented are the results of an analysis of electron bombardment ion propulsion systems for use in the transportation and on-orbit operations of large space systems. Using baseline technology from the ongoing primary propulsion program and other sources, preliminary estimates of the expected characteristics of key system elements such as thrusters and propellant storage systems have been performed. Projections of expected thruster performance on argon are presented based on identified constraints which limit the achievable thrust and/or power density of bombardment thrusters. System characteristics are then evaluated as a function of thruster diameter and specific impulse.

Byers, D. C.↗
NASA NTRS1980

Solar electric propulsion - A versatile stage for earth orbiting missions

The paper examines recent developments in solar array and ion propulsion systems which make possible the utilization of readily available solar energy for spacecraft propulsion and operation. The Solar Electric Propulsion System (SEPS) stage represents a substantial increase in capability to perform interplanetary and earth orbiting missions due to the combination of high performance and low thrust. SEPS is an important augmentation to the Space Transportation System (STS) for numerous earth orbit missions because it can deliver a greatly increased total satellite mass to a geosynchronous orbit or greatly increase the on-orbit delta V capability.

Smith, D. D.↗
NASA NTRS2007

Boeing Low-Thrust Geosynchronous Transfer Mission Experience

Since 2000, Boeing 702 satellites have used electric propulsion for transfer to geostationary orbits. The use of the 25cm Xenon Ion Propulsion System (25cm XIPS) results in more than a tenfold increase in specific impulse with the corresponding decrease in propellant mass needed to complete the mission when compared to chemical propulsion[1]. In addition to more favorable mass properties, with the use of XIPS, the 702 has been able to achieve orbit insertions with higher accuracy than it would have been possible with the use of chemical thrusters. This paper describes the experience attained by using the 702 XIPS ascent strategy to transfer satellite to geosynchronous orbits.

Poole, Mark↗
NASA NTRS2013

The Status of Spacecraft Bus and Platform Technology Development under the NASA In-Space Propulsion Technology Program

NASA's In-Space Propulsion Technology (ISPT) program has been developing technologies for lowering the cost of planetary science missions. The technology areas include electric propulsion technologies, spacecraft bus technologies, entry vehicle technologies, and design tools for systems analysis and mission trajectories. The electric propulsion technologies include critical components of both gridded and non-gridded ion propulsion systems. The spacecraft bus technologies under development include an ultra-lightweight tank (ULTT) and advanced xenon feed system (AXFS). The entry vehicle technologies include the development of a multi-mission entry vehicle, mission design tools and aerocapture. The design tools under development include system analysis tools and mission trajectory design tools.

Anderson, David↗
NASA NTRS2013

Products from NASA's In-Space Propulsion Program Applicable to Low-Cost Planetary Missions

NASAs In-Space Propulsion Technology (ISPT) program has been developing technologies for lowering the cost of planetary science missions. The technology areas include electric propulsion technologies, spacecraft bus technologies, entry vehicle technologies, and design tools for systems analysis and mission trajectories. The electric propulsion technologies include critical components of both gridded and non-gridded ion propulsion systems. The spacecraft bus technologies under development include an ultra-lightweight tank (ULTT) and advanced xenon feed system (AXFS). The entry vehicle technologies include the development of a multi-mission entry vehicle, mission design tools and aerocapture. The design tools under development include system analysis tools and mission trajectory design tools.

Anderson, David↗
NASA NTRS2009

Managing Momentum on the Dawn Low Thrust Mission

Dawn is low-thrust interplanetary spacecraft enroute to the asteroids Vesta and Ceres in an effort to better understand the early creation of the solar system. After launch in September 2007, the spacecraft will flyby Mars in February 2009 before arriving at Vesta in summer of 2011 and Ceres in early 2015. Three solar electric ion-propulsion engines are used to provide the primary thrust for the Dawn spacecraft. Ion engines produce a very small but very efficient force, and therefore must be thrusting almost continuously to realize the necessary change in velocity to reach Vesta and Ceres.

RWA↗
NASA NTRS2003

A Comparison of Electric Propulsion Systems for Mars Exploration

Earth-Mars trajectories for multiple solar-powered spacecraft configurations were generated using Hall and ion propulsion systems utilizing the Direct Trajectory Optimization Method. Payload and power trades versus trip time were examined. Performance was compared for purely interplanetary flight and interplanetary flight with estimated spiral in to Mars orbit. Evaluating current ion and Hall thruster technologies, similar payload masses were delivered by each at equivalent trip times, but with the Hall thruster operating at a power level 10 kilowatts, on average, less than the ion thruster. The power difference for equivalent payload delivered should result in a significant cost savings.

Fiehler, Douglas↗
NASA NTRS1978

Solar electric propulsion for the Halley's Comet rendezvous mission - Foundation for future missions

Long range and long duration space missions require an inexpensive and powerful means of propulsion. Solar Electric Propulsion (SEP) is considered in terms of cost effectiveness and its present state of the art. An ion propulsion system is described, which will employ solar collectors (preferably bi-flat) to generate an electric current to operate an ion thruster. The expulsion of mercury, and later, argon, ions will provide the impulse to move the spacecraft. SEP in the range of 18-60 kW, and spacecraft velocities of up to 30 km/s are discussed with reference to future exploratory missions, including: asteroid and comet rendezvous, Mars sample return, planetary orbiters, and out-of-the-ecliptic space flight. SEP applicability to earth-orbital missions is also discussed, with attention to its effectiveness in moving large objects, e.g., satellite power stations, from LEO to GEO.

Austin, R. E.↗
NASA NTRS1994

A Segmented Ion Engine Design for Solar Elctric Propulsion Systems

Solar electric xenon ion propulsion can be used to deliver a substantial quantity of science instruments in rendezvous missions to small bodies such as comets and main belt asteroids with an Atlas IIAS launch vehicle. The performance of the ion propulsion system enables it to deliver typically more than twice the total mass to the destination in less than half the trip time relative to a chemical/ballistic approach using the same launch vehicle.

electron bombardment↗
NASA NTRS2014

Status of Propulsion Technology Development Under the NASA In-space Propulsion Technology Program

Since 2001, the In-Space Propulsion Technology (ISPT) program has been developing and delivering in-space propulsion technologies for NASA's Science Mission Directorate (SMD). These in-space propulsion technologies are applicable, and potentially enabling for future NASA Discovery, New Frontiers, Flagship and sample return missions currently under consideration. The ISPT program is currently developing technology in three areas that include Propulsion System Technologies, Entry Vehicle Technologies, and Systems Mission Analysis. ISPT's propulsion technologies include: 1) the 0.6-7 kW NASA's Evolutionary Xenon Thruster (NEXT) gridded ion propulsion system; 2) a 0.3-3.9kW Hall-effect electric propulsion (HEP) system for low cost and sample return missions; 3) the Xenon Flow Control Module (XFCM); 4) ultra-lightweight propellant tank technologies (ULTT); and 5) propulsion technologies for a Mars Ascent Vehicle (MAV). The HEP system is composed of the High Voltage Hall Accelerator (HiVHAc) thruster, a power processing unit (PPU), and the XFCM. NEXT and the HiVHAc are throttle-able electric propulsion systems for planetary science missions. The XFCM and ULTT are two component technologies which being developed with nearer-term flight infusion in mind. Several of the ISPT technologies are related to sample return missions needs like: MAV propulsion and electric propulsion. And finally, one focus of the SystemsMission Analysis area is developing tools that aid the application or operation of these technologies on wide variety of mission concepts. This paper provides a brief overview of the ISPT program, describing the development status and technology infusion readiness.

propellant tanks↗
NASA NTRS2014

Status of Propulsion Technology Development Under the NASA In-space Propulsion Technology Program

Since 2001, the In-Space Propulsion Technology (ISPT) program has been developing and delivering in-space propulsion technologies for NASA's Science Mission Directorate (SMD). These in-space propulsion technologies are applicable, and potentially enabling for future NASA Discovery, New Frontiers, Flagship and sample return missions currently under consideration. The ISPT program is currently developing technology in three areas that include Propulsion System Technologies, Entry Vehicle Technologies, and Systems Mission Analysis. ISPT's propulsion technologies include: 1) the 0.6-7 kW NASA's Evolutionary Xenon Thruster (NEXT) gridded ion propulsion system; 2) a 0.3-3.9kW Hall-effect electric propulsion (HEP) system for low cost and sample return missions; 3) the Xenon Flow Control Module (XFCM); 4) ultra-lightweight propellant tank technologies (ULTT); and 5) propulsion technologies for a Mars Ascent Vehicle (MAV). The HEP system is composed of the High Voltage Hall Accelerator (HiVHAc) thruster, a power processing unit (PPU), and the XFCM. NEXT and the HiVHAc are throttle-able electric propulsion systems for planetary science missions. The XFCM and ULTT are two component technologies which being developed with nearer-term flight infusion in mind. Several of the ISPT technologies are related to sample return missions needs like: MAV propulsion and electric propulsion. And finally, one focus of the SystemsMission Analysis area is developing tools that aid the application or operation of these technologies on wide variety of mission concepts. This paper provides a brief overview of the ISPT program, describing the development status and technology infusion readiness.

electric propulsion↗
NASA NTRS2014

Status of Propulsion Technology Development Under the NASA In-Space Propulsion Technology Program

Since 2001, the In-Space Propulsion Technology (ISPT) program has been developing and delivering in-space propulsion technologies for NASA's Science Mission Directorate (SMD). These in-space propulsion technologies are applicable, and potentially enabling for future NASA Discovery, New Frontiers, Flagship and sample return missions currently under consideration. The ISPT program is currently developing technology in three areas that include Propulsion System Technologies, Entry Vehicle Technologies, and Systems/Mission Analysis. ISPT's propulsion technologies include: 1) the 0.6-7 kW NASA's Evolutionary Xenon Thruster (NEXT) gridded ion propulsion system; 2) a 0.3-3.9kW Halleffect electric propulsion (HEP) system for low cost and sample return missions; 3) the Xenon Flow Control Module (XFCM); 4) ultra-lightweight propellant tank technologies (ULTT); and 5) propulsion technologies for a Mars Ascent Vehicle (MAV). The NEXT Long Duration Test (LDT) recently exceeded 50,000 hours of operation and 900 kg throughput, corresponding to 34.8 MN-s of total impulse delivered. The HEP system is composed of the High Voltage Hall Accelerator (HIVHAC) thruster, a power processing unit (PPU), and the XFCM. NEXT and the HIVHAC are throttle-able electric propulsion systems for planetary science missions. The XFCM and ULTT are two component technologies which being developed with nearer-term flight infusion in mind. Several of the ISPT technologies are related to sample return missions needs: MAV propulsion and electric propulsion. And finally, one focus of the Systems/Mission Analysis area is developing tools that aid the application or operation of these technologies on wide variety of mission concepts. This paper provides a brief overview of the ISPT program, describing the development status and technology infusion readiness.

systems analysis↗
NASA NTRS2007

NASA's Discovery Program: Moving Toward the Edge (of the Solar System)

NASA's Planetary Science , Division sponsors a competitive program of small spacecraft missions with the goal of performing focused science investigations that complement NASA's larger planetary science explorations at relatively low cost. The goal of the Discovery program is to launch many smaller missions with fast development times to increase our understanding of the solar system by exploring the planets, dwarf planets, their moons, and small bodies such as comets and asteroids. Discovery missions are solicited from the broad planetary science community approximately every 2 years. Active missions within the Discovery program include several with direct scientific or engineering connections to potential future missions to the edge of the solar system and beyond. In addition to those in the Discovery program are the missions of the New Frontiers program. The first New Frontiers mission. is the New Horizons mission to Pluto, which will explore this 38-AU distant dwarf planet and potentially some Kuiper Belt objects beyond. The Discovery program's Dawn mission, when launched in mid-2007, will use ion drive as its primary propulsion system. Ion propulsion is one of only two technologies that appear feasible for early interstellar precursor missions with practical flight times. The Kepler mission will explore the structure and diversity of extrasolar planetary systems, with an emphasis on the detection of Earth-size planets around other stars. Kepler will survey nearby solar systems searching for planets that may fall within the habitable zone,' a region surrounding a star within which liquid water may exist on a planet's surface - an essential ingredient for life as we know it. With its open and competitive approach to mission selections, the Discovery program affords scientists the opportunity to propose missions to virtually any solar system destination. With its emphasis on science and proven openness to the use of new technologies such as ion propulsion, missions flown as part of the program will test out technologies needed for future very deep-space exploration and potentially take us to these difficult and distant destinations.

Johnson, Les↗