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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 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

Commercialization and Human Settlement of the Moon and Cislunar Space Using ISRU, Fission Surface Power, and Advanced In-Space Propulsion Systems

Over 50 years have passed since themovie 2001: A Space Odyssey debuted in April 1968. In the film, Dr. Heywood Floyd flies to a large artificial gravity space station orbiting Earth aboard a commercial space plane. He then embarks on a commuter flight to the Moon arriving there 25 hours later. Today, on the 50th anniversary of the Apollo 11lunar landing, the images portrayed in 2001 remain well beyond our capabilities and 2100: A Space Odyssey seems a more appropriate title for Kubrick and Clarke's film. This paper looks at the key technologies, systems, and supporting infrastructure (in-situ resource utilization (ISRU), fission surface power (FSP), nuclear thermal propulsion (NTP), andorbiting propellant depots), that could be developed by NASA and the private sector over the next 30years allowing the operational capabilities presented in 2001 to be achieved, albeit on a more spartan scale.

Borowski, Stan↗
NASA NTRS2003

A fission powered Mars Telecommunications Orbiter mission concept

This paper details the objectives of the mission, the key constraints that influenced the mission design, and the flight and ground system implementation. Issues that influenced the mission architecture are discussed, as well as the technology assumptions.

space↗
NASA NTRSDate not supplied

ENABLING ARCHITECTURE TRADES AND DESIGN EXPLORATION FOR NUCLEAR ELECTRIC PROPULSION

Recent renewed interest in Nuclear Electric Propulsion (NEP) at NASA has driven the need for design space exploration and analysis of alternative architectures to evaluate performance and feasibility of NEP concepts. It has been over a decade since NASA last invested in Nuclear Electric Propulsion development efforts, and the landscape has shifted in both mission objectives and technology readiness levels. This also means that many of the engineering analyses and design frameworks tailored to NEP date back to the Jupiter Icy Moons Orbiter (JIMO) days of the early 2000s. Thus, a need was identified for updating and modernizing the modeling and simulation toolsets for NEP. This paper will detail the development efforts in the Marshall Space Flight Center’s Advanced Concepts Office, with a particular focus on the development of the NEP stage of the NEP-Chem vehicle. The paper will cover the various models used, and their current development status, as well as provide an overview of the integrated vehicle model and plans for further development.

Nuclear↗
NASA NTRSDate not supplied

Enabling Architecture Trades and Design Exploration for Nuclear Electric Propulsion

Recent renewed interest in Nuclear Electric Propulsion (NEP) at NASA has driven the need for design space exploration and analysis of alternative architectures to evaluate performance and feasibility of NEP concepts. It has been over a decade since NASA last invested in Nuclear Electric Propulsion development efforts, and the landscape has shifted in both mission objectives and technology readiness levels. This also means that many of the engineering analyses and design frameworks tailored to NEP date back to the Jupiter Icy Moons Orbiter (JIMO) days of the early 2000s. Thus, a need was identified for updating and modernizing the modeling and simulation toolsets for NEP. This paper will detail the development efforts in the Marshall Space Flight Center’s Advanced Concepts Office, with a particular focus on the development of the NEP stage of the NEP-Chem vehicle. The paper will cover the various models used, and their current development status, as well as provide an overview of the integrated vehicle model and plans for further development.

Nuclear↗
NASA NTRSDate not supplied

Production and Characterization of Additively Manufactured Radiator Panels with Integral Branching Heat Pipes for High-Temperature Heat Rejection

Emerging concepts for fission surface power and nuclear electric propulsion necessitate lightweight, mechanically robust, and thermally efficient heat rejection radiators. State-of-the-art intermediate-temperature (~400 K) composite radiator assemblies have been developed based on titanium-water heat pipes bonded to metal, graphite, and carbon-fiber-based panels. NASA has identified a need for new radiator concepts that can operate at even higher temperatures (500 – 600 K), minimize thermal resistances and thermal stress failures at bond interfaces, and approach areal densities of 2 – 3 kg m -2 . To meet these needs, our team is developing additively manufactured (AM) radiator panels with integral branching wicking heat pipe networks. Water is selected as the working fluid for this temperature range. Based on simulations and thermal vacuum experiments, these branching embedded heat pipe networks can efficiently distribute heat over panels for finned surface efficiencies of η f >70% at T H = 500 K input heat. This paper first presents laser powder-bed fusion AM strategies to produce embedded porous structures for wicking heat pipes in Inconel 718 and titanium alloys (commercially pure and Ti-6Al-4V alloys). Post-build chemical and thermal treatments are described that yield hydrophilic wicking surfaces for operation with water. Transient rate-of-rise experiments with water and acetone are reported that yield estimates for AM wick porosity (ϵ), permeability (K), and effective pore radius (r pore ). Based on the wick characterization results, small prototype radiator panels (75 × 125 mm) with integrated heat pipe networks were manufactured. Heat rejection performance data are presented from cold thermal vacuum testing, with heat input temperatures up to ~510 K. Future efforts will focus on improving heat pipe performance, optimizing radiator mass, and evaluating larger panels to assess scalability.

thermal management↗
NASA NTRS2024

Production and Characterization of Additively Manufactured Radiator Panels With Integral Branching Heat Pipes for High-Temperature Heat Rejection

Emerging concepts for fission surface power and nuclear electric propulsion necessitate lightweight, mechanically robust, and thermally efficient heat rejection radiators. State-of-the-art intermediate-temperature (~400 K) composite radiator assemblies have been developed based on titanium-water heat pipes bonded to metal, graphite, and carbon-fiber-based panels. NASA has identified a need for new radiator concepts that can operate at even higher temperatures (500 – 600 K), minimize thermal resistances and thermal stress failures at bond interfaces, and approach areal densities of 2 – 3 kg m -2 . To meet these needs, our team is developing additively manufactured (AM) radiator panels with integral branching wicking heat pipe networks. Water is selected as the working fluid for this temperature range. Based on simulations and thermal vacuum experiments, these branching embedded heat pipe networks can efficiently distribute heat over panels for finned surface efficiencies of η f >70% at T H = 500 K input heat. This paper first presents laser powder-bed fusion AM strategies to produce embedded porous structures for wicking heat pipes in Inconel 718 and titanium alloys (commercially pure and Ti-6Al-4V alloys). Post-build chemical and thermal treatments are described that yield hydrophilic wicking surfaces for operation with water. Transient rate-of-rise experiments with water and acetone are reported that yield estimates for AM wick porosity (ϵ), permeability (K), and effective pore radius ( r pore ). Based on the wick characterization results, small prototype radiator panels (75 × 125 mm) with integrated heat pipe networks were manufactured. Heat rejection performance data are presented from cold thermal vacuum testing, with heat input temperatures up to ~510 K. Future efforts will focus on improving heat pipe performance, optimizing radiator mass, and evaluating larger panels to assess scalability.

nuclear electric propulsion↗
NASA NTRS1971

Symposium on Uranium Plasmas: Research and Applications, 2nd, Atlanta, Ga., November 15-17, 1971, Collection of Technical Papers.

Results of theoretical and applied research related to fissioning uranium plasmas. Topics examined include uranium plasma instabilities, diagnostic techniques, radiant heat transfer characteristics, nuclear pumping of lasers, and various fission engine concepts. Engineering aspects considered for open-cycle gas core engines include effects of buoyancy on fuel containment, flow and criticality problems, effects of injection conditions, and radiation hazards. The nuclear light bulb engine, the mini-cavity reactor, the dust-bed reactor, and the colloid core reactor are also examined in terms of design and control considerations. Individual items are abstracted in this issue.

Source record↗
NASA NTRS1972

Development of a model and test equipment for cold flow tests at 500 atm of small nuclear light bulb configurations

A model and test equipment were developed and cold-flow-tested at greater than 500 atm in preparation for future high-pressure rf plasma experiments and in-reactor tests with small nuclear light bulb configurations. With minor exceptions, the model chamber is similar in design and dimensions to a proposed in-reactor geometry for tests with fissioning uranium plasmas in the nuclear furnace. The model and the equipment were designed for use with the UARL 1.2-MW rf induction heater in tests with rf plasmas at pressures up to 500 atm. A series of cold-flow tests of the model was then conducted at pressures up to about 510 atm. At 504 atm, the flow rates of argon and cooling water were 3.35 liter/sec (STP) and 26 gal/min, respectively. It was demonstrated that the model is capable of being operated for extended periods at the 500-atm pressure level and is, therefore, ready for use in initial high-pressure rf plasma experiments.

Jaminet, J. F.↗
NASA NTRS1972

What can nuclear energy do for society.

It is pointed out that the earth's crust holds 30,000 times as much energy in the form of fissionable atoms as fossil fuel. Moreover, nuclear fuel costs less per unit of energy than fossil fuel. Capital equipment used to release nuclear energy, on the other hand, is expensive. For commercial electric-power production and marine propulsion, advantages of nuclear power have outweighed disadvantages. As to nuclear submarines, applications other than military may prove feasible. The industry has proposed cargo submarines to haul oil from the Alaskan North Slope beneath the Arctic ice. Other possible applications for nuclear power are in air-cushion-vehicles, aircraft, and rockets.-

Rom, F. E.↗
NASA NTRS2011

Optical Sensors for Monitoring Gamma and Neutron Radiation

For safety and efficiency, nuclear reactors must be carefully monitored to provide feedback that enables the fission rate to be held at a constant target level via adjustments in the position of neutron-absorbing rods and moderating coolant flow rates. For automated reactor control, the monitoring system should provide calibrated analog or digital output. The sensors must survive and produce reliable output with minimal drift for at least one to two years, for replacement only during refueling. Small sensor size is preferred to enable more sensors to be placed in the core for more detailed characterization of the local fission rate and fuel consumption, since local deviations from the norm tend to amplify themselves. Currently, reactors are monitored by local power range meters (LPRMs) based on the neutron flux or gamma thermometers based on the gamma flux. LPRMs tend to be bulky, while gamma thermometers are subject to unwanted drift. Both electronic reactor sensors are plagued by electrical noise induced by ionizing radiation near the reactor core. A fiber optic sensor system was developed that is capable of tracking thermal neutron fluence and gamma flux in order to monitor nuclear reactor fission rates. The system provides near-real-time feedback from small- profile probes that are not sensitive to electromagnetic noise. The key novel feature is the practical design of fiber optic radiation sensors. The use of an actinoid element to monitor neutron flux in fiber optic EFPI (extrinsic Fabry-Perot interferometric) sensors is a new use of material. The materials and structure used in the sensor construction can be adjusted to result in a sensor that is sensitive to just thermal, gamma, or neutron stimulus, or any combination of the three. The tested design showed low sensitivity to thermal and gamma stimuli and high sensitivity to neutrons, with a fast response time.

Boyd, Clark D.↗
NASA NTRS1967

Computer program FPIP-REV calculates fission product inventory for U-235 fission

Computer program calculates fission product inventories and source strengths associated with the operation of U-235 fueled nuclear power reactor. It utilizes a fission-product nuclide library of 254 nuclides, and calculates the time dependent behavior of the fission product nuclides formed by fissioning of U-235.

Brown, W. S.↗
NASA NTRS1976

Application of gaseous core reactors for transmutation of nuclear waste

An acceptable management scheme for high-level radioactive waste is vital to the nuclear industry. The hazard potential of the trans-uranic actinides and of key fission products is high due to their nuclear activity and/or chemical toxicity. Of particular concern are the very long-lived nuclides whose hazard potential remains high for hundreds of thousands of years. Neutron induced transmutation offers a promising technique for the treatment of problem wastes. Transmutation is unique as a waste management scheme in that it offers the potential for "destruction" of the hazardous nuclides by conversion to non-hazardous or more manageable nuclides. The transmutation potential of a thermal spectrum uranium hexafluoride fueled cavity reactor was examined. Initial studies focused on a heavy water moderated cavity reactor fueled with 5% enriched U-235-F6 and operating with an average thermal flux of 6 times 10 to the 14th power neutrons/sq cm-sec. The isotopes considered for transmutation were I-129, Am-241, Am-242m, Am-243, Cm-243, Cm-244, Cm-245, and Cm-246.

Schnitzler, B. G.↗
NASA NTRSDate not supplied

Nuclear Power Concepts for High-Power Electric Propulsion Missions to Mars

Under the Mars Transportation Assessment Study, NASA and DOE are performing analyses and generating concepts for crewed Nuclear Electric Propulsion (NEP) missions to Mars. This paper presents the results of trade studies and concept development for the nuclear electric power system, consisting of the fission reactor, radiation shielding, power conversion, heat rejection and power management & distribution (PMAD). The nuclear power team completed trade studies to evaluate different reactor and power conversion technologies and developed preliminary concepts for the crew shielding, waste heat radiators, and PMAD. The initial results suggest that a modified terrestrial microreactor combined with supercritical CO2 Brayton conversion could be used to perform the crew and cargo missions with satisfactory performance and modest risk.

Lee Mason↗
NASA NTRS2010

Advanced Space Fission Propulsion Systems

Fission has been considered for in-space propulsion since the 1940s. Nuclear Thermal Propulsion (NTP) systems underwent extensive development from 1955-1973, completing 20 full power ground tests and achieving specific impulses nearly twice that of the best chemical propulsion systems. Space fission power systems (which may eventually enable Nuclear Electric Propulsion) have been flown in space by both the United States and the Former Soviet Union. Fission is the most developed and understood of the nuclear propulsion options (e.g. fission, fusion, antimatter, etc.), and fission has enjoyed tremendous terrestrial success for nearly 7 decades. Current space nuclear research and technology efforts are focused on devising and developing first generation systems that are safe, reliable and affordable. For propulsion, the focus is on nuclear thermal rockets that build on technologies and systems developed and tested under the Rover/NERVA and related programs from the Apollo era. NTP Affordability is achieved through use of previously developed fuels and materials, modern analytical techniques and test strategies, and development of a small engine for ground and flight technology demonstration. Initial NTP systems will be capable of achieving an Isp of ~900 s at a relatively high thrust-to-weight ratio. The development and use of first generation space fission power and propulsion systems will provide new, game changing capabilities for NASA. In addition, development and use of these systems will provide the foundation for developing extremely advanced power and propulsion systems capable of routinely and affordably accessing any point in the solar system. The energy density of fissile fuel (8 x 10(exp 13) Joules/kg) is more than adequate for enabling extensive exploration and utilization of the solar system. For space fission propulsion systems, the key is converting the virtually unlimited energy of fission into thrust at the desired specific impulse and thrust-to-weight ratio. This presentation will discuss potential space fission propulsion options ranging from first generation systems to highly advanced systems. Ongoing research that shows promise for enabling second generation NTP systems with Isp greater than 1000 s will be discussed, as will the potential for liquid, gas, or plasma core systems. Space fission propulsion systems could also be used in conjunction with simple (water-based) propellant depots to enable routine, affordable missions to various destinations (e.g. moon, Mars, asteroids) once in-space infrastructure is sufficiently developed. As fuel and material technologies advance, very high performance Nuclear Electric Propulsion (NEP) systems may also become viable. These systems could enable sophisticated science missions, highly efficient cargo delivery, and human missions to numerous destinations. Commonalities between NTP, fission power systems, and NEP will be discussed.

Houts, Michael G.↗