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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 415 records · Page 23
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Design of propellant acquisition systems for advanced cryogenic space propulsion systems

This paper presents results of work conducted to expand the technology base and evolve practical propellant surface tension acquisition system designs for future cryogenic space vehicles. Surface tension screen device channel flow analysis and supporting tests showed that reasonable mesh sizes could provide the required retention performance. Integrated subsystem studies and development showed that practical and effective screen surface tension acquisition devices could be designed for typical applications, but that other interfacing feed subsystems are often constrained by the design of the particular acquisition device. These constraints may dominate the total feed system performance.

Burge, G. W.↗
NASA NTRS1992

An accelerated development, reduced cost approach to lunar/Mars exploration using a modular NTR-based space transportation system

Benefits and rationale for developing a common, modular lunar/Mars space transporation system (STS) based on nuclear thermal rocket (NTR) are presented. The modular NTR is based on three key components including a 50 klbf NERVA-derived engine used in clusters of 2 or 3, two standardized tank sizes developed for the First Lunar Outpost and Mars cargo vehicle applications, and a preintegrated truss/propellant feed system used for transferring LH2 from the drop tanks into the 'in-line' tank. It is concluded that, by using these components in a 'building block' fashion, a variety of single and multi-engine lunar and Mars vehicles can be configured to satisfy particular mission requirements.

Borowski, S.↗
NASA NTRS2005

An Overview of the VHITAL Program: A Two-Stage Bismuth Fed Very High Specific Impulse Thruster with Anode Layer

The Very High Isp Thruster with Anode Layer (VHITAL) is a two stage Hall thruster program that is a part of NASA's Prometheus Program in NASA's New Exploration Systems Mission Directorate (ESMD). It is a potentially viable low-cost alternative to ion engines for near-term NEP applications with the growth potential to support mid-term and far-term NEP missions... This paper will present an overview of the thruster fabrication, pre-existing TAL 160 demonstration, feed system development, lifetime assessment, contamination assessment, and mission study activities performed to date.

cathodes↗
NASA NTRS2021

Pre-Flight Assessment of Xenon Propellant Usage and Usage Uncertainty for the Psyche Mission

NASA’s Psyche mission will launch in 2022 and begin a 3.6-year cruise to the metallic asteroid Psyche, the largest metal asteroid in the solar system. All primary propulsion will be done with the flight-proven SPT-140 electric propulsion subsystem. The Psyche mission will feature the first use of Hall thrusters for a NASA mission, and the first use of Hall thrusters beyond cis-lunar space, which has presented some unique challenges. In this paper we describe the Psyche propellant feed system architecture, expected propellant usage for the mission, propellant gauging requirements, and challenges associated with propellant gauging. Data from two recent Maxar electric orbit-raising missions with SPT-140 thrusters are reviewed and used to assess in-flight performance. We develop a pressure-volume-temperature gauging method that incorporates the propellant temperature distributions observed in the flight data, and use this method to provide an improved quantitative understanding of in-flight propellant consumption rates and their uncertainties. The results are in excellent agreement with the results of standard Maxar gauging methods and we determine a propellant usage uncertainty of ± 7.1% 3σ based on flight telemetry. Additionally, we demonstrate that the bookkeeping method of propellant gauging accurately predicts the tank pressure flight data. This work has led to design changes in the Psyche spacecraft avionics that will further improve propellant gauging uncertainties, which is particularly important for later phases of the mission. Finally, we statistically combine the predicted propellant mass uncertainties from the two gauging methods and demonstrate that the system will meet the mission requirements for propellant uncertainty. Together, all of this work provides confidence that the Psyche mission can be successfully completed within the existing propellant budget and propellant tank capacity.

Baldwin, Jeff↗
NASA NTRS1993

GRYPHON: Air launched space booster

The project chosen for the winter semester Aero 483 class was the design of a next generation Air Launched Space Booster. Based on Orbital Sciences Corporation's Pegasus concept, the goal of Aero 483 was to design a 500,000 pound air launched space booster capable of delivering 17,000 pounds of payload to Low Earth Orbit and 8,000 pounds of payload to Geosynchronous Earth Orbit. The resulting launch vehicle was named the Gryphon. The class of forty senior aerospace engineering students was broken down into eight interdependent groups. Each group was assigned a subsystem or responsibility which then became their field of specialization. Spacecraft Integration was responsible for ensuring compatibility between subsystems. This group kept up to date on subsystem redesigns and informed those parties affected by the changes, monitored the vehicle's overall weight and dimensions, and calculated the mass properties of the booster. This group also performed the cost/profitability analysis of the Gryphon and obtained cost data for competing launch systems. The Mission Analysis Group was assigned the task of determining proper orbits, calculating the vehicle's flight trajectory for those orbits, and determining the aerodynamic characteristics of the vehicle. The Propulsion Group chose the engines that were best suited to the mission. This group also set the staging configurations for those engines and designed the tanks and fuel feed system. The commercial satellite market, dimensions and weights of typical satellites, and method of deploying satellites was determined by the Payloads Group. In addition, Payloads identified possible resupply packages for Space Station Freedom and identified those packages that were compatible with the Gryphon. The guidance, navigation, and control subsystems were designed by the Mission Control Group. This group identified required tracking hardware, communications hardware telemetry systems, and ground sites for the location of the Gryphon's mission control center. The Structures group was responsible for ensuring the structural integrity of the vehicle. Their designs included the payload shroud, payload support structure, exterior hull and engine support struts. The Gryphon's power requirements were determined by the Power/Thermal/Attitude Control Group. This group then selected suitable batteries and other components to meet these requirements. The group also designed heat shielding and cooling systems to ensure subsystem performance. In addition to these responsibilities this group designed the attitude control methods and RCS components for the vehicle. The Aircraft Integration Group was responsible for all aspects of the booster aircraft connection. This included the design of the connection structure and the drop mechanism. This group also designed the vehicle assembly facility and identified possible ground bases for the plane.

Source record↗
NASA NTRS2007

Cryogenic Technology Development for Exploration Missions

This paper reports the status and findings of different cryogenic technology research projects in support of the President s Vision for Space Exploration. The exploration systems architecture study is reviewed for cryogenic fluid management needs. It is shown that the exploration architecture is reliant on the cryogenic propellants of liquid hydrogen, liquid oxygen and liquid methane. Needs identified include: the key technologies of liquid acquisition devices, passive thermal and pressure control, low gravity mass gauging, prototype pressure vessel demonstration, active thermal control; as well as feed system testing, and Cryogenic Fluid Management integrated system demonstration. Then five NASA technology projects are reviewed to show how these needs are being addressed by technology research. Projects reviewed include: In-Space Cryogenic Propellant Depot; Experimentation for the Maturation of Deep Space Cryogenic Refueling Technology; Cryogenic Propellant Operations Demonstrator; Zero Boil-Off Technology Experiment; and Propulsion and Cryogenic Advanced Development. Advances are found in the areas of liquid acquisition of liquid oxygen, mass gauging of liquid oxygen via radio frequency techniques, computational modeling of thermal and pressure control, broad area cooling thermal control strategies, flight experiments for resolving low gravity issues of cryogenic fluid management. Promising results are also seen for Joule-Thomson pressure control devices in liquid oxygen and liquid methane and liquid acquisition of methane, although these findings are still preliminary.

Chato, David J.↗
NASA NTRS2017

Solar System Exploration Augmented by In-Situ Resource Utilization: Human Planetary Base Issues for Mercury and Saturn

Human and robotic missions to Mercury and Saturn are presented and analyzed with a range of propulsion options. Historical studies of space exploration, planetary spacecraft, and astronomy, in-situ resource utilization (ISRU), and industrialization all point to the vastness of natural resources in the solar system. Advanced propulsion benefitted from these resources in many ways. While advanced propulsion systems were proposed in these historical studies, further investigation of nuclear options using high power nuclear thermal and nuclear pulse propulsion as well as advanced chemical propulsion can significantly enhance these scenarios. Updated analyses based on these historical visions are presented. Nuclear thermal propulsion and ISRU enhanced chemical propulsion landers are assessed for Mercury missions. At Saturn, nuclear pulse propulsion with alternate propellant feed systems and Saturn moon exploration with chemical propulsion and nuclear electric propulsion options are discussed. Issues with using in-situ resource utilization on Mercury missions are discussed. At Saturn, the best locations for exploration and the use of the moons Titan and Enceladus as central locations for Saturn moon exploration is assessed.

Lunar↗
NASA NTRS2015

Solar System Exploration Augmented by In-Situ Resource Utilization: Human Mercury and Saturn Exploration

Human and robotic missions to Mercury and Saturn are presented and analyzed. Unique elements of the local planetary environments are discussed and included in the analyses and assessments. Using historical studies of space exploration, in-situ resource utilization (ISRU), and industrialization all point to the vastness of natural resources in the solar system. Advanced propulsion benefitted from these resources in many way. While advanced propulsion systems were proposed in these historical studies, further investigation of nuclear options using high power nuclear thermal and nuclear pulse propulsion as well as advanced chemical propulsion can significantly enhance these scenarios. Updated analyses based on these historical visions will be presented. Nuclear thermal propulsion and ISRU enhanced chemical propulsion landers are assessed for Mercury missions. At Saturn, nuclear pulse propulsion with alternate propellant feed systems and Titan exploration with chemical propulsion options are discussed.

Palaszewski, Bryan↗
NASA NTRS2016

Solar System Exploration Augmented by In-Situ Resource Utilization: Mercury and Saturn Propulsion Investigations

Human and robotic missions to Mercury and Saturn are presented and analyzed with a range of propulsion options. Historical studies of space exploration, in-situ resource utilization (ISRU), and industrialization all point to the vastness of natural resources in the solar system. Advanced propulsion benefitted from these resources in many ways. While advanced propulsion systems were proposed in these historical studies, further investigation of nuclear options using high power nuclear thermal and nuclear pulse propulsion as well as advanced chemical propulsion can significantly enhance these scenarios. Updated analyses based on these historical visions will be presented. Nuclear thermal propulsion and ISRU enhanced chemical propulsion landers are assessed for Mercury missions. At Saturn, nuclear pulse propulsion with alternate propellant feed systems and Titan exploration with chemical propulsion options are discussed. In-situ resource utilization was found to be critical in making Mercury missions more amenable for human visits. At Saturn, refueling using local atmospheric mining was found to be difficult to impractical, while refueling the Saturn missions from Uranus was more practical and less complex.

space propulsion↗
NASA NTRS2020

Solar System Exploration Augmented by In-Situ Resource Utilization: Human Mercury and Saturn Exploration

Human and robotic missions to Mercury and Saturn are presented and analyzed. Unique elements of the local planetary environments are discussed and included in the analyses and assessments. Historical studies of space exploration, in-situ resource utilization (ISRU), and industrialization all point to the vastness of natural resources in the solar system. Advanced propulsion benefitted from these resources in many ways. While advanced propulsion systems were proposed in these historical studies, further investigation of nuclear options using high power nuclear thermal and nuclear pulse propulsion as well as advanced chemical propulsion can significantly enhance these scenarios. Updated analyses based on these historical visions will be presented. Nuclear thermal propulsion and ISRU enhanced chemical propulsion landers are assessed for Mercury missions. At Saturn, nuclear pulse propulsion with alternate propellant feed systems and Titan exploration with chemical propulsion options are discussed.

Palaszewski, Bryan A.↗
NASA NTRS1990

LARC powder prepreg system

Thermoplastic prepregs of LARC-TPI have been produced in a fluidized bed unit on spread continuous fiber tows. The powders are melted on the fibers by radiant heating to adhere the polymer to the fiber. This process produces tow prepreg uniformly without imposing severe stress on the fibers or requiring long high temperature residence times for the polymer. Unit design theory and operating correlations have been developed to provide the basis for scale up to commercial operation. Special features of the operation are the pneumatic tow spreader, fluidized bed and resin feed systems.

Baucom, Robert M.↗
NASA NTRS1980

Development of methods of producing large areas of silicon sheet by the slicing of silicon ingots using Inside Diameter (I.D.) saws

Modifications to a 16 inch STC automated saw included: a programmable feed system; a crystal rotating system; and a STC dynatrack blade boring and control system. By controlling the plating operation and by grinding the cutting edge, 16 inch I.D. blades were produced with a cutting edge thickness of .22 mm. Crystal rotation mechanism was used to slice 100 mm diameter crystals with a 16 inch blade down to a thickness of .20 mm. Cutting rates with crystal rotation were generally slower than with standard plunge I.D. slicing techniques. Using programmed feeds and programmed rotation, maximum cutting rates were from 0.3 to 1.0 inches per minute.

Aharonyan, P.↗
NASA NTRS1999

Ion Thruster and Power Processor Developed for the Deep Space 1 Mission

The NASA Solar Electric Propulsion Technology Applications Readiness (NSTAR) Program has provided a single-string primary propulsion system to NASA's Deep Space 1 spacecraft. This spacecraft will carry about 81 kg of xenon propellant for the ion thruster, which can be throttled down from 2.3 to 0.5 kW as the spacecraft moves away from the Sun. The propellant load will provide about 20 months of propulsion at the one-half power throttle setpoint of 1.2 kW. This mission will validate the 2.5-kW ion propulsion system and will fly by the asteroid 1992 KD in 1999. If funding permits, Deep Space 1 also will encounter comets Wilson-Harrington and Borrelly in 2001. NASA Lewis Research Center's On-Board Propulsion Branch was responsible for the development of the 30-cm-diameter ion thruster, the 2.5-kW power processor unit (PPU), and the Digital Control and Interface Unit (DCIU) that controls the PPU/thruster/feed system and provides data and recovery from fault conditions. Lewis transferred the thruster and PPU technologies to the Hughes Electron Dynamics Division, which was selected to build two sets of flight thrusters, as well as the PPU's and DCIU's. Hughes subcontracted the DCIU development to Spectrum Astro Incorporated. The Jet Propulsion Laboratory (JPL) was primarily responsible for the NSTAR project management, thruster lifetests, the feed system, diagnostics, and the propulsion subsystem integration. A total of four engineering model thrusters and three breadboard PPU's were built, integrated, and tested. More than 50 development tests were conducted along with thruster design verification tests of 2000 and 1000 hours. In addition, an 8000-hr life demonstration test was successfully completed and demonstrated wear-rates consistent with full-power lifetimes in excess of 12,000 hours.

Sovey, James S.↗
NASA NTRS2015

Low-Mass, Low-Power Hall Thruster System

NASA is developing an electric propulsion system capable of producing 20 mN thrust with input power up to 1,000 W and specific impulse ranging from 1,600 to 3,500 seconds. The key technical challenge is the target mass of 1 kg for the thruster and 2 kg for the power processing unit (PPU). In Phase I, Busek Company, Inc., developed an overall subsystem design for the thruster/cathode, PPU, and xenon feed system. This project demonstrated the feasibility of a low-mass power processing architecture that replaces four of the DC-DC converters of a typical PPU with a single multifunctional converter and a low-mass Hall thruster design employing permanent magnets. In Phase II, the team developed an engineering prototype model of its low-mass BHT-600 Hall thruster system, with the primary focus on the low-mass PPU and thruster. The goal was to develop an electric propulsion thruster with the appropriate specific impulse and propellant throughput to enable radioisotope electric propulsion (REP). This is important because REP offers the benefits of nuclear electric propulsion without the need for an excessively large spacecraft and power system.

Pote, Bruce↗
NASA NTRS1973

Study and design of cryogenic propellant acquisition systems. Volume 1: Design studies

An in-depth study and selection of practical propellant surface tension acquisition system designs for two specific future cryogenic space vehicles, an advanced cryogenic space shuttle auxiliary propulsion system and an advanced space propulsion module is reported. A supporting laboratory scale experimental program was also conducted to provide design information critical to concept finalization and selection. Designs using localized pressure isolated surface tension screen devices were selected for each application and preliminary designs were generated. Based on these designs, large scale acquisition prototype hardware was designed and fabricated to be compatible with available NASA-MSFC feed system hardware.

Burge, G. W.↗
NASA NTRS1980

Development of methods of producing large areas of silicon sheet by the slicing of silicon ingots using Inside-Diameter (I.D.) saws

Inside diametar wafering equipment, blades and processes were used to develop methods to produce large areas of silicon sheet. Modifications to a 16 inch STC automated saw included: programmable feed system, crystal rotating system, and STC dynatrack blade monitoring and control system. By controlling the plating operation and by grinding of the cutting edge, 16 inch ID blades with a cutting edge thickness of .22 mm can be produced. Crystal rotation mechanism was used to slice 100 mm diameter crystals with a 16 inch blade down to a thickness of .20 mm. Cutting rates with crystal rotation were generally slower than with standard plunge ID slicing techniques. Using programmed feeds and programmed rotation, maximum cutting rates were from 0.3 to 1.0 inches per minute.

Aharonyan, P.↗
NASA NTRS1999

Laser Lightcraft Vehicle Design

Current space deployment vehicle research is investigating ways to lower the cost to place payloads into orbit. Beamed energy propulsion is one of the areas that are being studied. The Laser lightcraft concept, which uses a ground based laser as part of its propulsion system, falls into this category. This concept has been developed by previous Strategic Defense Initiative Office (SDIO) research. In this concept, the laser energy is reflected off of a mirror on the craft and is focused inside the cowl to created optical breakdown of the propellant. There are several concerns about the design that must be further studied. These include: 1) Thermodynamic analysis of the cryogenic fuel storage and feed systems, 2) Analysis of the regenerative cooling system for the primary optic, and 3) Analysis of focal blurring of the laser due to off-axis flight.

Buch, Kevin↗
NASA NTRS2004

Multi-Element Unstructured Analyses of Complex Valve Systems

The safe and reliable operation of high pressure test stands for rocket engine and component testing places an increased emphasis on the performance of control valves and flow metering devices. In this paper, we will present a series of high fidelity computational analyses of systems ranging from cryogenic control valves and pressure regulator systems to cavitating venturis that are used to support rocket engine and component testing at NASA Stennis Space Center. A generalized multi-element framework with sub-models for grid adaption, grid movement and multi-phase flow dynamics has been used to carry out the simulations. Such a framework provides the flexibility of resolving the structural and functional complexities that are typically associated with valve-based high pressure feed systems and have been difficult to deal with traditional CFD methods. Our simulations revealed a rich variety of flow phenomena such as secondary flow patterns, hydrodynamic instabilities, fluctuating vapor pockets etc. In the paper, we will discuss performance losses related to cryogenic control valves, and provide insight into the physics of the dominant multi-phase fluid transport phenomena that are responsible for the choking like behavior in cryogenic control elements. Additionally, we will provide detailed analyses of the modal instability that is observed in the operation of the dome pressure regulator valve. Such instabilities are usually not localized and manifest themselves as a system wide phenomena leading to an undesirable chatter at high flow conditions.

Sulyma, Peter↗