WorldWideScience

Sample records for nuclear pulse propulsion

  1. Nuclear Pulse Propulsion

    OpenAIRE

    Atanas, Dilov; Hasan, Osman; Nickolai, Larsen; Tom, Edwards

    2015-01-01

    This project aims to provide the reader with a comprehensive insight into the potential of nuclear fuels to accelerate spacecraft propulsion, shorten journey times and broaden our exploration of space. The current methods of space propulsion offer little in the way of efficiency in terms of cost, time and henceforth investment and research. The dwindling resources of the planet plus the exponential rise of overpopulation will ultimately push us towards exploration of worlds further afield ...

  2. Nuclear Cryogenic Propulsion Stage

    Science.gov (United States)

    Houts, Michael G.; Borowski, S. K.; George, J. A.; Kim, T.; Emrich, W. J.; Hickman, R. R.; Broadway, J. W.; Gerrish, H. P.; Adams, R. B.

    2012-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progress made under the NCPS project could help enable both advanced NTP and advanced NEP.

  3. Nuclear thermal propulsion program overview

    Science.gov (United States)

    Bennett, Gary L.

    1991-01-01

    Nuclear thermal propulsion program is described. The following subject areas are covered: lunar and Mars missions; national space policy; international cooperation in space exploration; propulsion technology; nuclear rocket program; and budgeting.

  4. Nuclear electric propulsion

    International Nuclear Information System (INIS)

    Keaton, P.W.; Tubb, D.J.

    1986-01-01

    The feasibility is investigated of using nuclear electric propulsion (NEP) for slow freighter ships traveling from a 500 km low Earth orbit (LEO) to the Moon's orbit about the Earth, and on to Mars. NEP is also shown to be feasible for transporting people to Mars on long conjunction-class missions lasting about nine months one way, and on short sprint missions lasting four months one way. Generally, it was not attempted to optimize ion exhaust velocities, but rather suitable parameters to demonstrate NEP feasibility were chosen. Various combinations of missions are compared with chemical and nuclear thermal propulsion (NTR) systems. Typically, NEP and NTR can accomplish the same lifting task with similar mass in LEO. When compared to chemical propulsion, NEP was found to accomplish the same missions with 40% less mass in LEO. These findings are sufficiently encouraging as to merit further studies with optimum systems

  5. Nuclear rocket propulsion

    International Nuclear Information System (INIS)

    Clark, J.S.; Miller, T.J.

    1991-01-01

    NASA has initiated planning for a technology development project for nuclear rocket propulsion systems for Space Exploration Initiative (SEI) human and robotic missions to the Moon and to Mars. An Interagency project is underway that includes the Department of Energy National Laboratories for nuclear technology development. This paper summarizes the activities of the project planning team in FY 1990 and FY 1991, discusses the progress to date, and reviews the project plan. Critical technology issues have been identified and include: nuclear fuel temperature, life, and reliability; nuclear system ground test; safety; autonomous system operation and health monitoring; minimum mass and high specific impulse

  6. Nuclear propulsion systems engineering

    International Nuclear Information System (INIS)

    Madsen, W.W.; Neuman, J.E.: Van Haaften, D.H.

    1992-01-01

    The Nuclear Energy for Rocket Vehicle Application (NERVA) program of the 1960's and early 1970's was dramatically successful, with no major failures during the entire testing program. This success was due in large part to the successful development of a systems engineering process. Systems engineering, properly implemented, involves all aspects of the system design and operation, and leads to optimization of theentire system: cost, schedule, performance, safety, reliability, function, requirements, etc. The process must be incorporated from the very first and continued to project completion. This paper will discuss major aspects of the NERVA systems engineering effort, and consider the implications for current nuclear propulsion efforts

  7. Brief review on pulse laser propulsion

    Science.gov (United States)

    Yu, Haichao; Li, Hanyang; Wang, Yan; Cui, Lugui; Liu, Shuangqiang; Yang, Jun

    2018-03-01

    Pulse laser propulsion (PLP) is an advanced propulsion concept can be used across a variety of fields with a wide range of applications. PLP reflects superior payload as well as decreased launch costs in comparison with other conventional methods of producing thrust, such as chemical propulsion or electric propulsion. Numerous researchers have attempted to exploit the potential applications of PLP. This paper first reviews concepts relevant to PLP, including the propulsion modes, breakdown regimes, and propulsion efficiency; the propulsion targets for different materials with the pulse laser are then discussed in detail, including the propulsion of solid and liquid microspheres. PLP applications such as the driven microsatellite, target surface particle removal, and orbital debris removal are also discussed. Although the PLP has been applied to a variety of fields, further research is yet warranted to establish its application in the aerospace field.

  8. The Nuclear Cryogenic Propulsion Stage

    Science.gov (United States)

    Houts, Michael G.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Broadway, Jeramie W.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Borowski, Stanley K.; Scott, John

    2014-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progress made under the NCPS project could help enable both advanced NTP and advanced Nuclear Electric Propulsion (NEP). Nuclear propulsion can be affordable and viable compared to other propulsion systems and must overcome a biased public fear due to hyper-environmentalism and a false perception of radiation and explosion risk.

  9. Reactors for nuclear electric propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Buden, D.; Angelo, J.A. Jr.

    1981-01-01

    Propulsion is the key to space exploitation and power is the key to propulsion. This paper examines the role of nuclear fission reactors as the primary power source for high specific impulse electric propulsion systems for space missions of the 1980s and 1990s. Particular mission applications include transfer to and a reusable orbital transfer vehicle from low-Earth orbit to geosynchronous orbit, outer planet exploration and reconnaissance missions, and as a versatile space tug supporting lunar resource development. Nuclear electric propulsion is examined as an indispensable component in space activities of the next two decades.

  10. Reactors for nuclear electric propulsion

    International Nuclear Information System (INIS)

    Buden, D.; Angelo, J.A. Jr.

    1981-01-01

    Propulsion is the key to space exploitation and power is the key to propulsion. This paper examines the role of nuclear fission reactors as the primary power source for high specific impulse electric propulsion systems for space missions of the 1980s and 1990s. Particular mission applications include transfer to and a reusable orbital transfer vehicle from low-Earth orbit to geosynchronous orbit, outer planet exploration and reconnaissance missions, and as a versatile space tug supporting lunar resource development. Nuclear electric propulsion is examined as an indispensable component in space activities of the next two decades

  11. NASA's Nuclear Thermal Propulsion Project

    Science.gov (United States)

    Houts, Michael G.; Mitchell, Doyce P.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Clement, Steven; Borowski, Stanley K.; hide

    2015-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation NTP system could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of a first generation NTP in the development of advanced nuclear propulsion systems could be analogous to the role of the DC- 3 in the development of advanced aviation. Progress made under the NTP project could also help enable high performance fission power systems and Nuclear Electric Propulsion (NEP).

  12. Nuclear thermal propulsion workshop overview

    International Nuclear Information System (INIS)

    Clark, J.S.

    1991-01-01

    NASA is planning an Exploration Technology Program as part of the Space Exploration Initiative to return U.S. astronauts to the moon, conduct intensive robotic exploration of the moon and Mars, and to conduct a piloted mission to Mars by 2019. Nuclear Propulsion is one of the key technology thrust for the human mission to Mars. The workshop addresses NTP (Nuclear Thermal Rocket) technologies with purpose to: assess the state-of-the-art of nuclear propulsion concepts; assess the potential benefits of the concepts for the mission to Mars; identify critical, enabling technologies; lay-out (first order) technology development plans including facility requirements; and estimate the cost of developing these technologies to flight-ready status. The output from the workshop will serve as a data base for nuclear propulsion project planning

  13. LASL nuclear rocket propulsion program

    Energy Technology Data Exchange (ETDEWEB)

    Schreiber, R.E.

    1956-04-01

    The immediate objective of the LASL nuclear propulsion (Rover) program is the development of a heat exchanger reactor system utilizing uranium-graphite fuel elements and ammonia propellant. This program is regarded as the first step in the development of nuclear propulsion systems for missiles. The major tasks of the program include the investigation of materials at high temperatures, development of fuel elements, investigation of basic reactor characteristics, investigation of engine control problems, detailed engine design and ground testing. The organization and scheduling of the initial development program have been worked out in some detail. Only rather general ideas exist concerning the projection of this work beyond 1958.

  14. Nuclear Thermal Propulsion Development Risks

    Science.gov (United States)

    Kim, Tony

    2015-01-01

    There are clear advantages of development of a Nuclear Thermal Propulsion (NTP) for a crewed mission to Mars. NTP for in-space propulsion enables more ambitious space missions by providing high thrust at high specific impulse ((is) approximately 900 sec) that is 2 times the best theoretical performance possible for chemical rockets. Missions can be optimized for maximum payload capability to take more payload with reduced total mass to orbit; saving cost on reduction of the number of launch vehicles needed. Or missions can be optimized to minimize trip time significantly to reduce the deep space radiation exposure to the crew. NTR propulsion technology is a game changer for space exploration to Mars and beyond. However, 'NUCLEAR' is a word that is feared and vilified by some groups and the hostility towards development of any nuclear systems can meet great opposition by the public as well as from national leaders and people in authority. The public often associates the 'nuclear' word with weapons of mass destruction. The development NTP is at risk due to unwarranted public fears and clear honest communication of nuclear safety will be critical to the success of the development of the NTP technology. Reducing cost to NTP development is critical to its acceptance and funding. In the past, highly inflated cost estimates of a full-scale development nuclear engine due to Category I nuclear security requirements and costly regulatory requirements have put the NTP technology as a low priority. Innovative approaches utilizing low enriched uranium (LEU). Even though NTP can be a small source of radiation to the crew, NTP can facilitate significant reduction of crew exposure to solar and cosmic radiation by reducing trip times by 3-4 months. Current Human Mars Mission (HMM) trajectories with conventional propulsion systems and fuel-efficient transfer orbits exceed astronaut radiation exposure limits. Utilizing extra propellant from one additional SLS launch and available

  15. Nuclear gas core propulsion research program

    Science.gov (United States)

    Diaz, Nils J.; Dugan, Edward T.; Anghaie, Samim

    1993-01-01

    Viewgraphs on the nuclear gas core propulsion research program are presented. The objectives of this research are to develop models and experiments, systems, and fuel elements for advanced nuclear thermal propulsion rockets. The fuel elements under investigation are suitable for gas/vapor and multiphase fuel reactors. Topics covered include advanced nuclear propulsion studies, nuclear vapor thermal rocket (NVTR) studies, and ultrahigh temperature nuclear fuels and materials studies.

  16. Legal Implications of Nuclear Propulsion for Space Objects

    Science.gov (United States)

    Pop, V.

    2002-01-01

    This paper is intended to examine nuclear propulsion concepts such as "Project Orion", "Project Daedalus", NERVA, VASIMIR, from the legal point of view. The UN Principles Relevant to the Use of Nuclear Power Sources in Outer Space apply to nuclear power sources in outer space devoted to the generation of electric power on board space objects for non-propulsive purposes, and do not regulate the use of nuclear energy as a means of propulsion. However, nuclear propulsion by means of detonating atomic bombs (ORION) is, in principle, banned under the 1963 Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space, and Under Water. The legality of use of nuclear propulsion will be analysed from different approaches - historical (i.e. the lawfulness of these projects at the time of their proposal, at the present time, and in the future - in the light of the mutability and evolution of international law), spatial (i.e. the legal regime governing peaceful nuclear explosions in different spatial zones - Earth atmosphere, Earth orbit, Solar System, and interstellar space), and technical (i.e, the legal regime applicable to different nuclear propulsion techniques, and to the various negative effects - e.g. damage to other space systems as an effect of the electromagnetic pulse, etc). The paper will analyse the positive law, and will also come with suggestions "de lege ferenda".

  17. Philosophy for nuclear thermal propulsion

    International Nuclear Information System (INIS)

    Buden, D.; Madsen, W.; Redd, L.

    1993-01-01

    The philosophy used for development of nuclear thermal propulsion will determine the cost, schedule and risk associated with the activities. As important is the impression of the decision makers. If the development cost is higher than the product value, it is doubtful that funding will ever be available. On the other hand, if the development supports the economic welfare of the country with a high rate of return, the probability of funding greatly increases. The philosophy is divided into: realism, design, operations and qualification. ''Realism'' addresses such items as political acceptability, potential customers, robustness-flexibility, public acceptance, decisions as needed, concurrent engineering, and the possible role of the CIS. ''Design'' addresses ''minimum requirement,'' built in safety and reliability redundancy, emphasize on eliminating risk at lowest levels, and the possible inclusion of electric generation. ''Operations'' addresses sately, environment, operations, design margins and degradation modes. ''Qualification'' addresses testing needs and test facilities

  18. NASA program planning on nuclear electric propulsion

    Science.gov (United States)

    Bennett, Gary L.; Miller, Thomas J.

    1992-01-01

    As part of the focused technology planning for future NASA space science and exploration missions, NASA has initiated a focused technology program to develop the technologies for nuclear electric propulsion and nuclear thermal propulsion. Beginning in 1990, NASA began a series of interagency planning workshops and meetings to identify key technologies and program priorities for nuclear propulsion. The high-priority, near-term technologies that must be developed to make NEP operational for space exploration include scaling thrusters to higher power, developing high-temperature power processing units, and developing high power, low-mass, long-lived nuclear reactors.

  19. Nuclear Thermal Propulsion for Advanced Space Exploration

    Science.gov (United States)

    Houts, M. G.; Borowski, S. K.; George, J. A.; Kim, T.; Emrich, W. J.; Hickman, R. R.; Broadway, J. W.; Gerrish, H. P.; Adams, R. B.

    2012-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progress made under the NCPS project could help enable both advanced NTP and advanced Nuclear Electric Propulsion (NEP).

  20. Nuclear Cryogenic Propulsion Stage for Mars Exploration

    Science.gov (United States)

    Houts, M. G.; Borowski, S. K.; George, J. A.; Kim, T.; Emrich, W. J.; Hickman, R. R.; Broadway, J. W.; Gerrish, H. P.; Adams, R. B.

    2012-01-01

    The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progress made under the NCPS project could help enable both advanced NTP and advanced Nuclear Electric Propulsion (NEP).

  1. Space Nuclear Thermal Propulsion (SNTP) program

    Science.gov (United States)

    Bleeker, Gary A.

    1993-01-01

    An overview of the Space Nuclear Thermal Propulsion program is presented in graphic form. A program organizational chart is presented that shows the government and industry participants. Enabling technologies and test facilities and approaches are also addressed.

  2. Performance Criteria of Nuclear Space Propulsion Systems

    Science.gov (United States)

    Shepherd, L. R.

    Future exploration of the solar system on a major scale will require propulsion systems capable of performance far greater than is achievable with the present generation of rocket engines using chemical propellants. Viable missions going deeper into interstellar space will be even more demanding. Propulsion systems based on nuclear energy sources, fission or (eventually) fusion offer the best prospect for meeting the requirements. The most obvious gain coming from the application of nuclear reactions is the possibility, at least in principle, of obtaining specific impulses a thousandfold greater than can be achieved in chemically energised rockets. However, practical considerations preclude the possibility of exploiting the full potential of nuclear energy sources in any engines conceivable in terms of presently known technology. Achievable propulsive power is a particularly limiting factor, since this determines the acceleration that may be obtained. Conventional chemical rocket engines have specific propulsive powers (power per unit engine mass) in the order of gigawatts per tonne. One cannot envisage the possibility of approaching such a level of performance by orders of magnitude in presently conceivable nuclear propulsive systems. The time taken, under power, to reach a given terminal velocity is proportional to the square of the engine's exhaust velocity and the inverse of its specific power. An assessment of various nuclear propulsion concepts suggests that, even with the most optimistic assumptions, it could take many hundreds of years to attain the velocities necessary to reach the nearest stars. Exploration within a range of the order of a thousand AU, however, would appear to offer viable prospects, even with the low levels of specific power of presently conceivable nuclear engines.

  3. A development approach for nuclear thermal propulsion

    International Nuclear Information System (INIS)

    Buden, D.

    1992-01-01

    The cost and time to develop nuclear thermal propulsion systems are very approach dependent. The objectives addressed are the development of an ''acceptable'' nuclear thermal propulsion system that can be used as part of the transportation system for people to explore Mars and the enhancement performance of other missions, within highly constrained budgets and schedules. To accomplish this, it was necessary to identify the cost drivers considering mission parameters, safety of the crew, mission success, facility availability and time and cost to construct new facilities, qualification criteria, status of technologies, management structure, and use of such system engineering techniques as concurrent engineering

  4. Nuclear Propulsion for Space (Rev.)

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, William R; Schwenk, Francis C

    1971-01-01

    The operation of nuclear rockets and a description of the development of nuclear rockets in the U.S. is given. Early developments and Project Rover, Project Pluto, and the NERVA (Nuclear Engine for Rocket Vehicle Application) Program are detailed. The Nuclear Rocket Development Station facilities in Nevada are described. The possibilities and advantages of using nuclear rockets for missions beginning from an earth orbit and moving outward toward higher earth orbits, the moon, and the planets are discussed.

  5. Nuclear thermal propulsion engine cost trade studies

    International Nuclear Information System (INIS)

    Paschall, R.K.

    1993-01-01

    The NASA transportation strategy for the Mars Exploration architecture includes the use of nuclear thermal propulsion as the primary propulsion system for Mars transits. It is anticipated that the outgrowth of the NERVA/ROVER programs will be a nuclear thermal propulsion (NTP) system capable of providing the propulsion for missions to Mars. The specific impulse (Isp) for such a system is expected to be in the 870 s range. Trade studies were conducted to investigate whether or not it may be cost effective to invest in a higher performance (Isp>870 s) engine for nuclear thermal propulsion for missions to Mars. The basic cost trades revolved around the amount of mass that must be transported to low-earth orbit prior to each Mars flight and the cost to launch that mass. The mass required depended on the assumptions made for Mars missions scenarios including piloted/cargo flights, number of Mars missions, and transit time to Mars. Cost parameters included launch cost, program schedule for development and operations, and net discount rate. The results were very dependent on the assumptions that were made. Under some assumptions, higher performance engines showed cost savings in the billions of dollars; under other assumptions, the additional cost to develop higher performance engines was not justified

  6. Nuclear Thermal Propulsion (prior to FY15: Nuclear Cryogenic Propulsion Stage)

    Data.gov (United States)

    National Aeronautics and Space Administration — A key goal of the project is to address critical, long-term nuclear thermal propulsion (NTP) technology challenges and issues through development, analysis, and...

  7. Nuclear Cryogenic Propulsion Stage Affordable Development Strategy

    Science.gov (United States)

    Doughty, Glen E.; Gerrish, H. P.; Kenny, R. J.

    2014-01-01

    The development of nuclear power for space use in nuclear thermal propulsion (NTP) systems will involve significant expenditures of funds and require major technology development efforts. The development effort must be economically viable yet sufficient to validate the systems designed. Efforts are underway within the National Aeronautics and Space Administration's (NASA) Nuclear Cryogenic Propulsion Stage Project (NCPS) to study what a viable program would entail. The study will produce an integrated schedule, cost estimate and technology development plan. This will include the evaluation of various options for test facilities, types of testing and use of the engine, components, and technology developed. A "Human Rating" approach will also be developed and factored into the schedule, budget and technology development approach.

  8. Disposal modes for Mars transfer nuclear propulsion

    Science.gov (United States)

    Stancati, Michael L.; Friedlander, Alan L.

    1991-01-01

    A managed disposal approach is proposed that would place the nuclear stage or vehicle in a highly stable orbit at modest cost to mission performance. The approach requires only a small increase in initial mass in LEO, but should be included in preliminary trajectory design and performance calculations. The mass penalty is expected to be larger for all-up flight profiles, or in cases of high-thrust propulsion systems for the cargo vehicle.

  9. Hydrogen Wave Heater for Nuclear Thermal Propulsion Component Testing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA has identified Nuclear Thermal Propulsion (NTP) as a propulsion concept which could provide the fastest trip times to Mars and as the preferred concept for...

  10. MSFC nuclear thermal propulsion technology program

    Science.gov (United States)

    Swint, Shane

    1993-01-01

    Viewgraphs on non-nuclear materials assessment, nuclear thermal propulsion (NTP) turbomachinery technologies, and high temperature superconducting magnetic bearing technology are presented. The objective of the materials task is to identify and evaluate candidate materials for use in NTP turbomachinery and propellant feed system applications. The objective of the turbomachinery technology task is to develop and validate advanced turbomachinery technologies at the component and turbopump assembly levels. The objective of the high temperature superconductors (HTS) task is to develop and validate advanced technology for HTS passive magnetic/hydrostatic bearing.

  11. Nuclear Propulsion for Space Applications

    Science.gov (United States)

    Houts, M. G.; Bechtel, R. D.; Borowski, S. K.; George, J. A.; Kim, T.; Emrich, W. J.; Hickman, R. R.; Broadway, J. W.; Gerrish, H. P.; Adams, R. B.

    2013-01-01

    Basics of Nuclear Systems: Long history of use on Apollo and space science missions. 44 RTGs and hundreds of RHUs launched by U.S. during past 4 decades. Heat produced from natural alpha (a) particle decay of Plutonium (Pu-238). Used for both thermal management and electricity production. Used terrestrially for over 65 years. Fissioning 1 kg of uranium yields as much energy as burning 2,700,000 kg of coal. One US space reactor (SNAP-10A) flown (1965). Former U.S.S.R. flew 33 space reactors. Heat produced from neutron-induced splitting of a nucleus (e.g. U-235). At steady-state, 1 of the 2 to 3 neutrons released in the reaction causes a subsequent fission in a "chain reaction" process. Heat converted to electricity, or used directly to heat a propellant. Fission is highly versatile with many applications.

  12. Shielding Development for Nuclear Thermal Propulsion

    Science.gov (United States)

    Caffrey, Jarvis A.; Gomez, Carlos F.; Scharber, Luke L.

    2015-01-01

    Radiation shielding analysis and development for the Nuclear Cryogenic Propulsion Stage (NCPS) effort is currently in progress and preliminary results have enabled consideration for critical interfaces in the reactor and propulsion stage systems. Early analyses have highlighted a number of engineering constraints, challenges, and possible mitigating solutions. Performance constraints include permissible crew dose rates (shared with expected cosmic ray dose), radiation heating flux into cryogenic propellant, and material radiation damage in critical components. Design strategies in staging can serve to reduce radiation scatter and enhance the effectiveness of inherent shielding within the spacecraft while minimizing the required mass of shielding in the reactor system. Within the reactor system, shield design is further constrained by the need for active cooling with minimal radiation streaming through flow channels. Material selection and thermal design must maximize the reliability of the shield to survive the extreme environment through a long duration mission with multiple engine restarts. A discussion of these challenges and relevant design strategies are provided for the mitigation of radiation in nuclear thermal propulsion.

  13. NASA's progress in nuclear electric propulsion technology

    Science.gov (United States)

    Stone, James R.; Doherty, Michael P.; Peecook, Keith M.

    1993-01-01

    The National Aeronautics and Space Administration (NASA) has established a requirement for Nuclear Electric Propulsion (NEP) technology for robotic planetary science mission applications with potential future evolution to systems for piloted Mars vehicles. To advance the readiness of NEP for these challenging missions, a near-term flight demonstration on a meaningful robotic science mission is very desirable. The requirements for both near-term and outer planet science missions are briefly reviewed, and the near-term baseline system established under a recent study jointly conducted by the Lewis Research Center (LeRC) and the Jet Propulsion Laboratory (JPL) is described. Technology issues are identified where work is needed to establish the technology for the baseline system, and technology opportunities which could provide improvement beyond baseline capabilities are discussed. Finally, the plan to develop this promising technology is presented and discussed.

  14. Ultrahigh Specific Impulse Nuclear Thermal Propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Anne Charmeau; Brandon Cunningham; Samim Anghaie

    2009-02-09

    Research on nuclear thermal propulsion systems (NTP) have been in forefront of the space nuclear power and propulsion due to their design simplicity and their promise for providing very high thrust at reasonably high specific impulse. During NERVA-ROVER program in late 1950's till early 1970's, the United States developed and ground tested about 18 NTP systems without ever deploying them into space. The NERVA-ROVER program included development and testing of NTP systems with very high thrust (~250,000 lbf) and relatively high specific impulse (~850 s). High thrust to weight ratio in NTP systems is an indicator of high acceleration that could be achieved with these systems. The specific impulse in the lowest mass propellant, hydrogen, is a function of square root of absolute temperature in the NTP thrust chamber. Therefor optimizing design performance of NTP systems would require achieving the highest possible hydrogen temperature at reasonably high thrust to weight ratio. High hydrogen exit temperature produces high specific impulse that is a diret measure of propellant usage efficiency.

  15. Oxygen Containment System Options for Nuclear Thermal Propulsion Testing

    Data.gov (United States)

    National Aeronautics and Space Administration — All nuclear thermal propulsion (NTP) ground testing conducted in the 1950s and 1960s during the ROVER/(Nuclear Engine Rocket Vehicle Application (NERVA) program...

  16. Nuclear propulsion in high yield vessels

    International Nuclear Information System (INIS)

    Vergara Aimone, Julio

    2000-01-01

    Current developments in advanced ship design brings high-speed maritime transportation closer to reality, aiming to create new markets and to recover a fraction of the high value goods now shipped only by air. High-speed transport is growing at a rate of 15% per year, higher than air transport and at a fraction of air tariffs. Although such growth rate is restricted to passengers and automobiles, there is a potential for high-speed cargo in some routes. A recent proposal is Fast Ship, a 260 m long, 40 m wide concept designed to cruise from Philadelphia to Cherbourg in less that 4 days, for a door-to-door timely cargo delivery of 7 days, thanks to an advanced hull design, and a high power propulsion plant to compensate for weather-related delays. However, almost 40% of the total operation cost would be fuel. This appears to be a natural application for nuclear power, in a similar way to the golden age of this technology. A nuclear Fast Ship would save almost 5000 tons of a fuel per trip, and about half of such spare might be available for additional cargo. Furthermore, operation costs would be smaller and very stable to resource price fluctuation, plus a few other advantages. For other ocean markets, such as the Asia-America route, nuclear power would become a much better choice. This paper discusses the reactor type and layout suitable for such application. The ship designer is aware of the current proposal, although the power pack is not readily available today and its political aspects have not been dealt with. The economy of our nation relies on exports and almost 90% of such flow goes by sea. It is also possible that in the future, Mercosur might have a dependency on such high-speed transport mode and propulsion system (au)

  17. Nuclear modules for space electric propulsion

    International Nuclear Information System (INIS)

    Difilippo, F.C.

    1998-01-01

    Analysis of interplanetary cargo and piloted missions requires calculations of the performances and masses of subsystems to be integrated in a final design. In a preliminary and scoping stage the designer needs to evaluate options iteratively by using fast computer simulations. The Oak Ridge National Laboratory (ORNL) has been involved in the development of models and calculational procedures for the analysis (neutronic and thermal hydraulic) of power sources for nuclear electric propulsion. The nuclear modules will be integrated into the whole simulation of the nuclear electric propulsion system. The vehicles use either a Brayton direct-conversion cycle, using the heated helium from a NERVA-type reactor, or a potassium Rankine cycle, with the working fluid heated on the secondary side of a heat exchanger and lithium on the primary side coming from a fast reactor. Given a set of input conditions, the codes calculate composition. dimensions, volumes, and masses of the core, reflector, control system, pressure vessel, neutron and gamma shields, as well as the thermal hydraulic conditions of the coolant, clad and fuel. Input conditions are power, core life, pressure and temperature of the coolant at the inlet of the core, either the temperature of the coolant at the outlet of the core or the coolant mass flow and the fluences and integrated doses at the cargo area. Using state-of-the-art neutron cross sections and transport codes, a database was created for the neutronic performance of both reactor designs. The free parameters of the models are the moderator/fuel mass ratio for the NERVA reactor and the enrichment and the pitch of the lattice for the fast reactor. Reactivity and energy balance equations are simultaneously solved to find the reactor design. Thermalhydraulic conditions are calculated by solving the one-dimensional versions of the equations of conservation of mass, energy, and momentum with compressible flow. 10 refs., 1 tab

  18. Nuclear modules for space electric propulsion

    Science.gov (United States)

    Difilippo, F. C.

    1998-01-01

    Analysis of interplanetary cargo and piloted missions requires calculations of the performances and masses of subsystems to be integrated in a final design. In a preliminary and scoping stage the designer needs to evaluate options iteratively by using fast computer simulations. The Oak Ridge National Laboratory (ORNL) has been involved in the development of models and calculational procedures for the analysis (neutronic and thermal hydraulic) of power sources for nuclear electric propulsion. The nuclear modules will be integrated into the whole simulation of the nuclear electric propulsion system. The vehicles use either a Brayton direct-conversion cycle, using the heated helium from a NERVA-type reactor, or a potassium Rankine cycle, with the working fluid heated on the secondary side of a heat exchanger and lithium on the primary side coming from a fast reactor. Given a set of input conditions, the codes calculate composition. dimensions, volumes, and masses of the core, reflector, control system, pressure vessel, neutron and gamma shields, as well as the thermal hydraulic conditions of the coolant, clad and fuel. Input conditions are power, core life, pressure and temperature of the coolant at the inlet of the core, either the temperature of the coolant at the outlet of the core or the coolant mass flow and the fluences and integrated doses at the cargo area. Using state-of-the-art neutron cross sections and transport codes, a database was created for the neutronic performance of both reactor designs. The free parameters of the models are the moderator/fuel mass ratio for the NERVA reactor and the enrichment and the pitch of the lattice for the fast reactor. Reactivity and energy balance equations are simultaneously solved to find the reactor design. Thermalhydraulic conditions are calculated by solving the one-dimensional versions of the equations of conservation of mass, energy, and momentum with compressible flow.

  19. System model development for nuclear thermal propulsion

    International Nuclear Information System (INIS)

    Walton, J.T.; Perkins, K.R.; Buksa, J.J.; Worley, B.A.; Dobranich, D.

    1992-01-01

    A critical enabling technology in the evolutionary development of nuclear thermal propulsion (NTP) is the ability to predict the system performance under a variety of operating conditions. Since October 1991, US (DOE), (DOD) and NASA have initiated critical technology development efforts for NTP systems to be used on Space Exploration Initiative (SEI) missions to the Moon and Mars. This paper presents the strategy and progress of an interagency NASA/DOE/DOD team for NTP system modeling. It is the intent of the interagency team to develop several levels of computer programs to simulate various NTP systems. An interagency team was formed for this task to use the best capabilities available and to assure appropriate peer review. The vision and strategy of the interagency team for developing NTP system models will be discussed in this paper. A review of the progress on the Level 1 interagency model is also presented

  20. A novel nuclear-powered propulsion system for ship

    International Nuclear Information System (INIS)

    Liu Tao; Han Weishi

    2003-01-01

    A novel nuclear-powered propulsion system for ship is presented in this paper. In this system, a minitype liquid sodium-cooled reactor is used as power; alkali-metal thermal-to-electric conversion (AMTEC) cells are utilized to transform the heat energy to electric energy and superconducting magneto-hydrodynamic (MHD) work as propulsion. This nuclear-powered propulsion system has great advantages in low noise, high speed, long survivability and simple manipulation. It has great significance for the development of propulsion system. (author)

  1. Modular Pulsed Plasma Electric Propulsion System for Cubesats

    Science.gov (United States)

    Perez, Andres Dono; Gazulla, Oriol Tintore; Teel, George Lewis; Mai, Nghia; Lukas, Joseph; Haque, Sumadra; Uribe, Eddie; Keidar, Michael; Agasid, Elwood

    2014-01-01

    Current capabilities of CubeSats must be improved in order to perform more ambitious missions. Electric propulsion systems will play a key role due to their large specific impulse. Compared to other propulsion alternatives, their simplicity allows an easier miniaturization and manufacturing of autonomous modules into the nano and pico-satellite platform. Pulsed Plasma Thrusters (PPTs) appear as one of the most promising technologies for the near term. The utilization of solid and non-volatile propellants, their low power requirements and their proven reliability in the large scale make them great candidates for rapid implementation. The main challenges are the integration and miniaturization of all the electronic circuitry into a printed circuit board (PCB) that can satisfy the strict requirements that CubeSats present. NASA Ames and the George Washington University have demonstrated functionality and control of three discrete Micro-Cathode Arc Thrusters (CAT) using a bench top configuration that was compatible with the ARC PhoneSat Bus. This demonstration was successfully conducted in a vaccum chamber at the ARC Environmental Test Laboratory. A new effort will integrate a low power Plasma Processing Unit and two plasma thrusters onto a single printed circuit board that will utilize less than 13 U of Bus volume. The target design will be optimized for the accommodation into the PhoneSatEDISON Demonstration of SmallSatellite Networks (EDSN) bus as it uses the same software interface application, which was demonstrated in the previous task. This paper describes the design, integration and architecture of the proposed propulsion subsystem for a planned Technology Demonstration Mission. In addition, a general review of the Pulsed Plasma technology available for CubeSats is presented in order to assess the necessary challenges to overcome further development.

  2. Nuclear Electric Propulsion for Outer Space Missions

    Science.gov (United States)

    Barret, Chris

    2003-01-01

    Today we know of 66 moons in our very own Solar System, and many of these have atmospheres and oceans. In addition, the Hubble (optical) Space Telescope has helped us to discover a total of 100 extra-solar planets, i.e., planets going around other suns, including several solar systems. The Chandra (X-ray) Space Telescope has helped us to discover 33 Black Holes. There are some extremely fascinating things out there in our Universe to explore. In order to travel greater distances into our Universe, and to reach planetary bodies in our Solar System in much less time, new and innovative space propulsion systems must be developed. To this end NASA has created the Prometheus Program. When one considers space missions to the outer edges of our Solar System and far beyond, our Sun cannot be relied on to produce the required spacecraft (s/c) power. Solar energy diminishes as the square of the distance from the Sun. At Mars it is only 43% of that at Earth. At Jupiter, it falls off to only 3.6% of Earth's. By the time we get out to Pluto, solar energy is only .066% what it is on Earth. Therefore, beyond the orbit of Mars, it is not practical to depend on solar power for a s/c. However, the farther out we go the more power we need to heat the s/c and to transmit data back to Earth over the long distances. On Earth, knowledge is power. In the outer Solar System, power is knowledge. It is important that the public be made aware of the tremendous space benefits offered by Nuclear Electric Propulsion (NEP) and the minimal risk it poses to our environment. This paper presents an overview of the reasons for NEP systems, along with their basic components including the reactor, power conversion units (both static and dynamic), electric thrusters, and the launch safety of the NEP system.

  3. Recent Advances in Nuclear Powered Electric Propulsion for Space Exploration

    Science.gov (United States)

    Cassady, R. Joseph; Frisbee, Robert H.; Gilland, James H.; Houts, Michael G.; LaPointe, Michael R.; Maresse-Reading, Colleen M.; Oleson, Steven R.; Polk, James E.; Russell, Derrek; Sengupta, Anita

    2007-01-01

    Nuclear and radioisotope powered electric thrusters are being developed as primary in-space propulsion systems for potential future robotic and piloted space missions. Possible applications for high power nuclear electric propulsion include orbit raising and maneuvering of large space platforms, lunar and Mars cargo transport, asteroid rendezvous and sample return, and robotic and piloted planetary missions, while lower power radioisotope electric propulsion could significantly enhance or enable some future robotic deep space science missions. This paper provides an overview of recent U.S. high power electric thruster research programs, describing the operating principles, challenges, and status of each technology. Mission analysis is presented that compares the benefits and performance of each thruster type for high priority NASA missions. The status of space nuclear power systems for high power electric propulsion is presented. The paper concludes with a discussion of power and thruster development strategies for future radioisotope electric propulsion systems,

  4. Test facilities for evaluating nuclear thermal propulsion systems

    International Nuclear Information System (INIS)

    Beck, D.F.; Allen, G.C.; Shipers, L.R.; Dobranich, D.; Ottinger, C.A.; Harmon, C.D.; Fan, W.C.; Todosow, M.

    1992-01-01

    Interagency panels evaluating nuclear thermal propulsion (NTP) development options have consistently recognized the need for constructing a major new ground test facility to support fuel element and engine testing. This paper summarizes the requirements, configuration, and baseline performance of some of the major subsystems designed to support a proposed ground test complex for evaluating nuclear thermal propulsion fuel elements and engines being developed for the Space Nuclear Thermal Propulsion (SNTP) program. Some preliminary results of evaluating this facility for use in testing other NTP concepts are also summarized

  5. Superconducting Electric Boost Pump for Nuclear Thermal Propulsion, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A submersible, superconducting electric boost pump sized to meet the needs of future Nuclear Thermal Propulsion systems in the 25,000 lbf thrust range is proposed....

  6. Book no.9. Nuclear naval propulsion: a comprehensive inventory

    International Nuclear Information System (INIS)

    2002-04-01

    This document presents the nuclear reactors and fuels used for ship propulsion. A review is made of the present day condition of the fleet of nuclear submarines and other ships worldwide with an assessment of the related risks. An inventory is given of the known submarine accidents between 1960 and 2002. Finally the design of the future nuclear submarines is presented. (J.S.)

  7. Laser-supported detonation waves and pulsed laser propulsion

    International Nuclear Information System (INIS)

    Kare, J.

    1990-01-01

    A laser thermal rocket uses the energy of a large remote laser, possibly ground-based, to heat an inert propellant and generate thrust. Use of a pulsed laser allows the design of extremely simple thrusters with very high performance compared to chemical rockets. The temperatures, pressures, and fluxes involved in such thrusters (10 4 K, 10 2 atmospheres, 10 7 w/cm 2 ) typically result in the creation of laser-supported detonation (LSD) waves. The thrust cycle thus involves a complex set of transient shock phenomena, including laser-surface interactions in the ignition of the LSD wave, laser-plasma interactions in the LSD wave itself, and high-temperature nonequilibrium chemistry behind the LSD wave. The SDIO Laser Propulsion Program is investigating these phenomena as part of an overall effort to develop the technology for a low-cost Earth-to-orbit laser launch system. We will summarize the Program's approach to developing a high performance thruster, the double-pulse planar thruster, and present an overview of some results obtained to date, along with a discussion of the many research question still outstanding in this area

  8. Space Nuclear Thermal Propulsion (SNTP) Air Force facility

    Science.gov (United States)

    Beck, David F.

    The Space Nuclear Thermal Propulsion (SNTP) Program is an initiative within the US Air Force to acquire and validate advanced technologies that could be used to sustain superior capabilities in the area or space nuclear propulsion. The SNTP Program has a specific objective of demonstrating the feasibility of the particle bed reactor (PBR) concept. The term PIPET refers to a project within the SNTP Program responsible for the design, development, construction, and operation of a test reactor facility, including all support systems, that is intended to resolve program technology issues and test goals. A nuclear test facility has been designed that meets SNTP Facility requirements. The design approach taken to meet SNTP requirements has resulted in a nuclear test facility that should encompass a wide range of nuclear thermal propulsion (NTP) test requirements that may be generated within other programs. The SNTP PIPET project is actively working with DOE and NASA to assess this possibility.

  9. Radioisotope Electric Propulsion (REP): A Near-Term Approach to Nuclear Propulsion

    Science.gov (United States)

    Schmidt, George R.; Manzella, David H.; Kamhawi, Hani; Kremic, Tibor; Oleson, Steven R.; Dankanich, John W.; Dudzinski, Leonard A.

    2009-01-01

    Studies over the last decade have shown radioisotope-based nuclear electric propulsion to be enhancing and, in some cases, enabling for many potential robotic science missions. Also known as radioisotope electric propulsion (REP), the technology offers the performance advantages of traditional reactor-powered electric propulsion (i.e., high specific impulse propulsion at large distances from the Sun), but with much smaller, affordable spacecraft. Future use of REP requires development of radioisotope power sources with system specific powers well above that of current systems. The US Department of Energy and NASA have developed an advanced Stirling radioisotope generator (ASRG) engineering unit, which was subjected to rigorous flight qualification-level tests in 2008, and began extended lifetime testing later that year. This advancement, along with recent work on small ion thrusters and life extension technology for Hall thrusters, could enable missions using REP sometime during the next decade.

  10. Tutorial on nuclear thermal propulsion safety for Mars

    International Nuclear Information System (INIS)

    Buden, D.

    1992-01-01

    Safety is the prime design requirement for nuclear thermal propulsion (NTP). It must be built in at the initiation of the design process. An understanding of safety concerns is fundamental to the development of nuclear rockets for manned missions to Mars and many other applications that will be enabled or greatly enhanced by the use of nuclear propulsion. To provide an understanding of the basic issues, a tutorial has been prepared. This tutorial covers a range of topics including safety requirements and approaches to meet these requirements, risk and safety analysis methodology, NERVA reliability and safety approach, and life cycle risk assessments

  11. Nuclear Propulsion and Power Non-Nuclear Test Facility (NP2NTF): Preliminary Analysis and Feasibility Assessment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Nuclear reactors, which power nuclear propulsion and power systems, and the nuclear radiation and residual radioactivity associated with these systems, impose...

  12. Effluent treatment options for nuclear thermal propulsion system ground tests

    International Nuclear Information System (INIS)

    Shipers, L.R.; Brockmann, J.E.

    1992-01-01

    A variety of approaches for handling effluent from nuclear thermal propulsion system ground tests in an environmentally acceptable manner are discussed. The functional requirements of effluent treatment are defined and concept options are presented within the framework of these requirements. System concepts differ primarily in the choice of fission-product retention and waste handling concepts. The concept options considered range from closed cycle (venting the exhaust to a closed volume or recirculating the hydrogen in a closed loop) to open cycle (real time processing and venting of the effluent). This paper reviews the strengths and weaknesses of different methods to handle effluent from nuclear thermal propulsion system ground tests

  13. Engine cycle design considerations for nuclear thermal propulsion systems

    International Nuclear Information System (INIS)

    Pelaccio, D.G.; Scheil, C.M.; Collins, J.T.

    1993-01-01

    A top-level study was performed which addresses nuclear thermal propulsion system engine cycle options and their applicability to support future Space Exploration Initiative manned lunar and Mars missions. Technical and development issues associated with expander, gas generator, and bleed cycle near-term, solid core nuclear thermal propulsion engines are identified and examined. In addition to performance and weight the influence of the engine cycle type on key design selection parameters such as design complexity, reliability, development time, and cost are discussed. Representative engine designs are presented and compared. Their applicability and performance impact on typical near-term lunar and Mars missions are shown

  14. Nuclear propulsion: an indispensable know-how to national sovereignty

    International Nuclear Information System (INIS)

    Picard, Michel; Tertrais, Bruno

    2006-01-01

    This report proposes a detailed presentation of the role nuclear-powered submarines in the French defence strategy, policy and security, and also a focus on the role of nuclear propulsion in these respects. The first part presents an overview of the role of submarines in the French strategy. It addresses the choice and interest of a deterrence policy for France, describes the role of submarines in this deterrence, and the role of SSNs in the French defence and security policy (support to deterrence, other strategic functions, protection). In the second part, the authors highlight the crucial role of nuclear propulsion by proposing an overview of a century of submarine evolution, by outlining their stealth and detection in above water and underwater warfare, by presenting SSBNs, by giving an overview of the different capacities of modern SSNs (weapons, above water warfare, under water warfare, ground strike capacities, special operations). It finally proposes an assessment of submarine operations. The last part addresses perspectives of evolution of operational requirements within the framework of the French strategy, its consequences on submarine acquisition programmes (for France and for the USA), its consequences in terms of numbers of SSNs and SSBNs, and its consequences in terms necessity of an industrial background. It also addresses European perspectives in terms of design, construction and abilities in the field of nuclear propulsion, and briefly other applications in marine nuclear propulsion. Issues of export and proliferation are also briefly addressed. Appendices propose presentations of the existing fleet of SSNs and SSBNs in the world

  15. Nuclear Electric Propulsion for the Exploration of the Outer Planets

    Science.gov (United States)

    Noca, M.; Polk, J. E.; Lenard, R.

    2001-01-01

    New power and propulsion technology efforts such as the DS-1 ion propulsion system demonstration and renewed interest in space nuclear power sources call for a reassessment of the mission benefits of Nuclear Electric Propulsion (NEP). In this study, a large emphasis has been placed in defining the NEP vehicle configuration and corresponding subsystem elements in order to produce an estimate of the vehicle's payload delivery capability which is as credible as possible. Both a 100 kWe and a 1 MWe system are defined. Various Outer Planet missions are evaluated using NEP, such as a Pluto Orbiter, a Europa Lander and Sample Return, attain/Saturn Sample Return and a Neptune Orbiter. Additional information is contained in the original extended abstract.

  16. Numerical analysis of a nuclear fuel element for nuclear thermal propulsion

    Science.gov (United States)

    Wang, Ten-See; Schutzenhofer, Luke

    1991-01-01

    A computational fluid dynamics model with porosity and permeability formulations in the transport equations has been developed to study the concept of nuclear thermal propulsion through the analysis of a pulsed irradiation of a particle bed element (PIPE). The numerical model is a time-accurate pressure-based formulation. An adaptive upwind scheme is employed for spatial discretization. The upwind scheme is based on second- and fourth-order central differencing with adaptive artificial dissipation. Multiblocked porosity regions have been formulated to model the cold frit, particle bed, and hot frit. Multiblocked permeability regions have been formulated to describe the flow shaping effect from the thickness-varying cold frit. Computational results for several zero-power density PIPEs and an elevated-particle-temperature PIPE are presented. The implications of the computational results are discussed.

  17. Nuclear reactor plant development for submarine propulsion system

    International Nuclear Information System (INIS)

    Gladkov, G.A.

    1992-01-01

    History of creating nuclear submarines in the USSR is considered. The above-mentioned works began in 1952. Water cooled and moderated reactor was chosen for the submarine propulsion system. Small-sized high-intensity and high-mobile power facility meeting the submarine requirements was created

  18. An historical collection of papers on nuclear thermal propulsion

    Science.gov (United States)

    The present volume of historical papers on nuclear thermal propulsion (NTP) encompasses NTP technology development regarding solid-core NTP technology, advanced concepts from the early years of NTP research, and recent activities in the field. Specific issues addressed include NERVA rocket-engine technology, the development of nuclear rocket propulsion at Los Alamos, fuel-element development, reactor testing for the Rover program, and an overview of NTP concepts and research emphasizing two decades of NASA research. Also addressed are the development of the 'nuclear light bulb' closed-cycle gas core and a demonstration of a fissioning UF6 gas in an argon vortex. The recent developments reviewed include the application of NTP to NASA's Lunar Space Transportation System, the use of NTP for the Space Exploration Initiative, and the development of nuclear rocket engines in the former Soviet Union.

  19. Scoping calculations of power sources for nuclear electric propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Difilippo, F.C. [Oak Ridge National Lab., TN (United States)

    1994-05-01

    This technical memorandum describes models and calculational procedures to fully characterize the nuclear island of power sources for nuclear electric propulsion. Two computer codes were written: one for the gas-cooled NERVA derivative reactor and the other for liquid metal-cooled fuel pin reactors. These codes are going to be interfaced by NASA with the balance of plant in order to making scoping calculations for mission analysis.

  20. Scoping calculations of power sources for nuclear electric propulsion

    International Nuclear Information System (INIS)

    Difilippo, F.C.

    1994-05-01

    This technical memorandum describes models and calculational procedures to fully characterize the nuclear island of power sources for nuclear electric propulsion. Two computer codes were written: one for the gas-cooled NERVA derivative reactor and the other for liquid metal-cooled fuel pin reactors. These codes are going to be interfaced by NASA with the balance of plant in order to making scoping calculations for mission analysis

  1. Nuclear radiation problems, unmanned thermionic reactor ion propulsion spacecraft

    Science.gov (United States)

    Mondt, J. F.; Sawyer, C. D.; Nakashima, A.

    1972-01-01

    A nuclear thermionic reactor as the electric power source for an electric propulsion spacecraft introduces a nuclear radiation environment that affects the spacecraft configuration, the use and location of electrical insulators and the science experiments. The spacecraft is conceptually configured to minimize the nuclear shield weight by: (1) a large length to diameter spacecraft; (2) eliminating piping penetrations through the shield; and (3) using the mercury propellant as gamma shield. Since the alumina material is damaged by the high nuclear radiation environment in the reactor it is desirable to locate the alumina insulator outside the reflector or develop a more radiation resistant insulator.

  2. Vehicle configuration options using nuclear propulsion for Mars missions

    Science.gov (United States)

    Emrich, William J.

    1993-01-01

    The solid core nuclear thermal rocket (NTR) provides an attractive means of providing the propulsive force needed to accomplish a wide array of space missions. With its factor of two or more advantage in Isp over chemical engines, nuclear propulsion provides the opportunity to accomplish space missions which are impractical by other means. This paper focuses on the use of a nuclear thermal rocket to accomplish a variety of space missions with emphasis on the manned Mars mission. The particle bed reactor (PBR) type nuclear engine was chosen as the baseline engine used to conduct the present study because of its perceived versatility over other nuclear propulsion systems in conducting a wide variety of tasks. This study baselines a particle bed reactor engine with an engine thrust-to-weight ratio (~11.5) and a specific impulse of ~950 s. It is shown that a PBR engine of this type will offer distinct advantages over the larger and heavier NERVA type nuclear engines.

  3. Design considerations for Mars transfer vehicles using nuclear thermal propulsion

    Science.gov (United States)

    Emrich, William J.

    1995-01-01

    The design of a Mars Transfer Vehicle (MTV) utilizing nuclear propulsion will require that careful consideration be given to the nuclear radiation environment in which it will operate. The extremely high neutron and gamma fluxes characteristic of nuclear thermal propulsion systems will cause significant heating of the fluid systems in close proximity to the reactor, especially in the lower propellant tanks. Crew radiation doses are also a concern particularly late in a mission when there is less shielding from the propellant tanks. In this study, various vehicle configuration and shielding strategies were examined and the resulting time dependent radiation fields evaluated. A common cluster of three particle bed reactor (PBR) engines were used in all configurations examined. In general, it appears that long, relatively narrow vehicles perform the best from a radiation standpoint, however, good shield optimization will be critical in maintaining a low radiation environment while minimizing the shield weight penalty.

  4. Assessment of Space Nuclear Thermal Propulsion Facility and Capability Needs

    Energy Technology Data Exchange (ETDEWEB)

    James Werner

    2014-07-01

    The development of a Nuclear Thermal Propulsion (NTP) system rests heavily upon being able to fabricate and demonstrate the performance of a high temperature nuclear fuel as well as demonstrating an integrated system prior to launch. A number of studies have been performed in the past which identified the facilities needed and the capabilities available to meet the needs and requirements identified at that time. Since that time, many facilities and capabilities within the Department of Energy have been removed or decommissioned. This paper provides a brief overview of the anticipated facility needs and identifies some promising concepts to be considered which could support the development of a nuclear thermal propulsion system. Detailed trade studies will need to be performed to support the decision making process.

  5. Revisiting Nuclear Thermal Propulsion for Human Mars Exploration

    Science.gov (United States)

    Percy, Thomas K.; Rodriguez, Mitchell

    2017-01-01

    Nuclear Thermal Propulsion (NTP) has long been considered as a viable in-space transportation alternative for delivering crew and cargo to the Martian system. While technology development work in nuclear propulsion has continued over the year, general interest in NTP propulsion applications has historically been tied directly to the ebb and flow of interest in sending humans to explore Mars. As far back as the 1960’s, plans for NTP-based human Mars exploration have been proposed and periodically revisited having most recently been considered as part of NASA Design Reference Architecture (DRA) 5.0. NASA has been investigating human Mars exploration strategies tied to its current Journey to Mars for the past few years however, NTP has only recently been added into the set of alternatives under consideration for in-space propulsion under the Mars Study Capability (MSC) team, formerly the Evolvable Mars Campaign (EMC) team. The original charter of the EMC was to find viable human Mars exploration approaches that relied heavily on technology investment work already underway, specifically related to the development of large Solar Electric Propulsion (SEP) systems. The EMC team baselined several departures from traditional Mars exploration ground rules to enable these types of architectures. These ground rule changes included lower energy conjunction class trajectories with corresponding longer flight times, aggregation of mission elements in cis-Lunar space rather than Low Earth Orbit (LEO) and, in some cases, the pre-deployment of Earth return propulsion systems to Mars. As the MSC team continues to refine the in-space transportation trades, an NTP-based architecture that takes advantage of some of these ground rule departures is being introduced.

  6. Mars mission performance enhancement with hybrid nuclear propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Dagle, J. E. [Pacific Northwest Lab., Richland, WA (United States); Noffsinger, K. E. [Pacific Northwest Lab., Richland, WA (United States); Segna, D. R. [USDOE Richland Operations Office, WA (United States)

    1992-01-01

    Nuclear electric propulsion (NEP), compared with chemical and nuclear thermal propulsion (NTP), can effectively deliver the same mass to Mars using much less propellant, consequently requiring less mass delivered to Earth orbit. The lower thrust of NEP requires a spiral trajectory near planetary bodies, which significantly increases the travel time. Although the total travel time is long, the portion of the flight time spent during interplanetary transfer is shorter, because the vehicle is thrusting for much longer periods of time. This has led to the supposition that NEP, although very attractive for cargo missions, is not suitable for piloted missions to Mars. However, with the application of a hybrid application of a hybrid approach to propulsion, the benefits of NEP can be utilized while drastically reducing the overall travel time required. Development of a dual-mode system, which utilizes high-thrust NTP to propel the spacecraft from the planetary gravitational influence and low-thrust NEP to accelerate in interplanetary space, eliminates the spiral trajectory and results in a much faster transit time than could be obtained by either NEP or NTP alone. This results in a mission profile with a lower initial mass in low Earth orbit. In addition, the propulsion system would have the capability to provide electrical power for mission applications.

  7. Electric propulsion. [pulsed plasma thruster and electron bombardment ion engine for MSAT attitude control and stationkeeping

    Science.gov (United States)

    1982-01-01

    An alternative propulsion subsystem for MSAT is presented which has a potential of reducing the satellite weight by more than 15%. The characteristics of pulsed plasma and ion engines are described and used to estimate of the mass of the propellant and thrusters for attitude control and stationkeeping functions for MSAT. Preliminary estimates indicate that the electric propulsion systems could also replace the large momentum wheels necessary to counteract the solar pressure; however, the fine pointing wheels would be retained. Estimates also show that either electric propulsion system can save approximately 18% to 20% of the initial 4,000 kg mass. The issues that require further experimentation are mentioned.

  8. Robotic planetary mission benefits from nuclear electric propulsion

    International Nuclear Information System (INIS)

    Kelley, J.H.; Yen, C.L.

    1992-01-01

    Several interesting planetary missions are either enabled or significantly enhanced by nuclear electric propulsion (NEP) in the 50 to 100 kW power range. These missions include a Pluto Orbiter/Probe with an 11-year flight time and several years of operational life in orbit versus a ballistic very fast (13 km/s) flyby which would take longer to get to Pluto and would have a very short time to observe the planet. (A ballistic orbiter would take about 40 years to get to Pluto.) Other missions include a Neptune Orbiter/Probe, a Jupiter Grand Tour orbiting each of the major moons in order, a Uranus Orbiter/Probe, a Multiple Mainbelt Asteroid Rendezvous orbiting six selected asteroids, and a Comet Nucleus Sample Return. This paper discusses potential missions and compares the nuclear electric propulsion option to the conventional ballistic approach on a parametric basis

  9. Nuclear propulsion control and health monitoring

    Science.gov (United States)

    Walter, P. B.; Edwards, R. M.

    1993-11-01

    An integrated control and health monitoring architecture is being developed for the Pratt & Whitney XNR2000 nuclear rocket. Current work includes further development of the dynamic simulation modeling and the identification and configuration of low level controllers to give desirable performance for the various operating modes and faulted conditions. Artificial intelligence and knowledge processing technologies need to be investigated and applied in the development of an intelligent supervisory controller module for this control architecture.

  10. Reactor physics in support of the naval nuclear propulsion programme

    International Nuclear Information System (INIS)

    Lisley, P.G.; Beeley, P.A.

    1994-01-01

    Reactor physics is a core component of all courses but in particular two postgraduate courses taught at the department in support of the naval nuclear propulsion programme. All of the courses include the following elements: lectures and problem solving exercises, laboratory work, experiments on the Jason zero power Argonaut reactor, demonstration of PWR behavior on a digital computer simulator and project work. This paper will highlight the emphasis on reactor physics in all elements of the education and training programme. (authors). 9 refs

  11. Democritos: preparing demonstrators for high power nuclear electric space propulsion

    OpenAIRE

    Masson, Frederic; Ruault, Jean-Marc; Worms, Jean-Claude; Detsis, Emmanouil; Beaurain, André; Lassoudiere, Francois; Gaia, Enrico; Tosi, Maria -Christina; Jansen, Frank; Bauer, Waldemar; Semenkin, Alexander; Tinsley, Tim; Hodgson, Zara

    2015-01-01

    The Democritos project aims at preparing demonstrators for a megawatt class nuclearelectric space propulsion. It is funded by Horizon 2020, the R&T program of the European Community. It is a new European and Russian project, including as partners: Nuclear National Laboratory (U.K.), DLR (Germany), The Keldysh Research Center (Russia), Thales Alenia Space Italia (Italy), Snecma (France), ESF (France) and CNES (France). IEAV (Brazil) will join as an observer. Democritos is the follo...

  12. Cycle Trades for Nuclear Thermal Rocket Propulsion Systems

    Science.gov (United States)

    White, C.; Guidos, M.; Greene, W.

    2003-01-01

    Nuclear fission has been used as a reliable source for utility power in the United States for decades. Even in the 1940's, long before the United States had a viable space program, the theoretical benefits of nuclear power as applied to space travel were being explored. These benefits include long-life operation and high performance, particularly in the form of vehicle power density, enabling longer-lasting space missions. The configurations for nuclear rocket systems and chemical rocket systems are similar except that a nuclear rocket utilizes a fission reactor as its heat source. This thermal energy can be utilized directly to heat propellants that are then accelerated through a nozzle to generate thrust or it can be used as part of an electricity generation system. The former approach is Nuclear Thermal Propulsion (NTP) and the latter is Nuclear Electric Propulsion (NEP), which is then used to power thruster technologies such as ion thrusters. This paper will explore a number of indirect-NTP engine cycle configurations using assumed performance constraints and requirements, discuss the advantages and disadvantages of each cycle configuration, and present preliminary performance and size results. This paper is intended to lay the groundwork for future efforts in the development of a practical NTP system or a combined NTP/NEP hybrid system.

  13. Hydrogen Wave Heater for Nuclear Thermal Propulsion Component Testing, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA has identified Nuclear Thermal Propulsion (NTP) as a propulsion concept which could provide the fastest trip times to Mars and as the preferred concept for...

  14. Virtual experiment instrument of nuclear pulse measuring

    International Nuclear Information System (INIS)

    Shan Jian; Zhao Xiuliang; Yu Hong; Zhang Meiqin

    2009-01-01

    Study on the scheme of application of virtual instrument(VI) technique in measuring of nuclear pulse. The system of Counter based on technology of LabVIEW and NI company's products USB-6009-DAQ is developed. Virtual nuclear instrument-Virtual Counter is realized. This system extends the application of technology of virtual instrument. The experimental results indicate that the system of Counter had the good counting measuring function of Nuclear Pulse. (authors)

  15. Nuclear Cryogenic Propulsion Stage Fuel Design and Fabrication

    Science.gov (United States)

    Hickman, Robert; Broadway, Jeramie; Mireles, Omar; Webb, Jon; Qualls, Lou

    2012-01-01

    Nuclear Cryogenic Propulsion Stage (NCPS) is a game changing technology for space exploration. Goal of assessing the affordability and viability of an NCPS includes these overall tasks: (1) Pre-conceptual design of the NCPS and architecture integration (2) NCPS Fuel Design and Testing (3) Nuclear Thermal Rocket Element Environmental Simulator (NTREES) (4) Affordable NCPS Development and Qualification Strategy (5) Second Generation NCPS Concepts. There is a critical need for fuels development. Fuel task objectives are to demonstrate capabilities and critical technologies using full scale element fabrication and testing.

  16. Space nuclear power, propulsion, and related technologies.

    Energy Technology Data Exchange (ETDEWEB)

    Berman, Marshall

    1992-01-01

    Sandia National Laboratories (Sandia) is one of the nation's largest research and development (R&D) facilities, with headquarters at Albuquerque, New Mexico; a laboratory at Livermore, California; and a test range near Tonopah, Nevada. Smaller testing facilities are also operated at other locations. Established in 1945, Sandia was operated by the University of California until 1949, when, at the request of President Truman, Sandia Corporation was formed as a subsidiary of Bell Lab's Western Electric Company to operate Sandia as a service to the U.S. Government without profit or fee. Sandia is currently operated for the U.S. Department of Energy (DOE) by AT&T Technologies, Inc., a wholly-owned subsidiary of AT&T. Sandia's responsibility is national security programs in defense and energy with primary emphasis on nuclear weapon research and development (R&D). However, Sandia also supports a wide variety of projects ranging from basic materials research to the design of specialized parachutes. Assets, owned by DOE and valued at more than $1.2 billion, include about 600 major buildings containing about 372,000 square meters (m2) (4 million square feet [ft2]) of floor space, located on land totalling approximately 1460 square kilometers (km2) (562 square miles [mi]). Sandia employs about 8500 people, the majority in Albuquerque, with about 1000 in Livermore. Approximately 60% of Sandia's employees are in technical and scientific positions, and the remainder are in crafts, skilled labor, and administrative positions. As a multiprogram national laboratory, Sandia has much to offer both industrial and government customers in pursuing space nuclear technologies. The purpose of this brochure is to provide the reader with a brief summary of Sandia's technical capabilities, test facilities, and example programs that relate to military and civilian objectives in space. Sandia is interested in forming partnerships with industry and government

  17. The United States Naval Nuclear Propulsion Program - Over 151 Million Miles Safely Steamed on Nuclear Power

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2015-03-01

    NNSA’s third mission pillar is supporting the U.S. Navy’s ability to protect and defend American interests across the globe. The Naval Reactors Program remains at the forefront of technological developments in naval nuclear propulsion and ensures a commanding edge in warfighting capabilities by advancing new technologies and improvements in naval reactor performance and reliability. In 2015, the Naval Nuclear Propulsion Program pioneered advances in nuclear reactor and warship design – such as increasing reactor lifetimes, improving submarine operational effectiveness, and reducing propulsion plant crewing. The Naval Reactors Program continued its record of operational excellence by providing the technical expertise required to resolve emergent issues in the Nation’s nuclear-powered fleet, enabling the Fleet to safely steam more than two million miles. Naval Reactors safely maintains, operates, and oversees the reactors on the Navy’s 82 nuclear-powered warships, constituting more than 45 percent of the Navy’s major combatants.

  18. High-temperature turbopump assembly for space nuclear thermal propulsion

    Science.gov (United States)

    Overholt, David M.

    1993-01-01

    The development of a practical, high-performance nuclear rocket by the U.S. Air Force Space Nuclear Thermal Propulsion (SNTP) program places high priority on maximizing specific impulse (ISP) and thrust-to-weight ratio. The operating parameters arising from these goals drive the propellant-pump design. The liquid hydrogen propellant is pressurized and pumped to the reactor inlet by the turbopump assembly (TPA). Rocket propulsion is effected by rapid heating of the propellant from 100 K to thousands of degrees in the particle-bed reactor (PBR). The exhausted propellant is then expanded through a high-temperature nozzle. One approach to achieve high performance is to use an uncooled carbon-carbon nozzle and duct turbine inlet. The high-temperature capability is obtained by using carbon-carbon throughout the TPA hot section. Carbon-carbon components in development include structural parts, turbine nozzles/stators, and turbine rotors. The technology spinoff is applicable to conventional liquid propulsion engines plus a wide variety of other turbomachinery applications.

  19. Carbon-carbon turbopump concept for Space Nuclear Thermal Propulsion

    Science.gov (United States)

    Overholt, David M.

    1993-06-01

    The U.S. Air Force Space Nuclear Thermal Propulsion (SNTP) program is placing high priority on maximizing specific impulse (ISP) and thrust-to-weight ratio in the development of a practical high-performance nuclear rocket. The turbopump design is driven by these goals. The liquid hydrogen propellant is pressurized and pumped to the reactor inlet by the turbopump assembly (TPA). Rocket propulsion is from rapid heating of the propellant from 180 R to thousands of degrees in the particle bed reactor (PBR). The exhausted propellant is then expanded through a high-temperature nozzle. A high-performance approach is to use an uncooled carbon-carbon nozzle and duct turbine inlet. Carbon-carbon components are used throughout the TPA hot section to obtain the high-temperature capability. Several carbon-carbon components are in development including structural parts, turbine nozzles/stators, and turbine rotors. The technology spinoff is applicable to conventional liquid propulsion engines and many other turbomachinery applications.

  20. Nuclear electric propulsion for planetary science missions: NASA technology program planning

    Science.gov (United States)

    Doherty, Michael P.

    1993-01-01

    This paper presents the status of technology program planning to develop those Nuclear Electric Propulsion technologies needed to meet the advanced propulsion system requirements for planetary science missions in the next century. The technology program planning is based upon technologies with significant development heritage: ion electric propulsion and the SP-100 space nuclear power technologies. Detailed plans are presented for the required ion electric propulsion technology development and demonstration. Closer coordination between space nuclear power and space electric propulsion technology programs is a necessity as technology plans are being further refined in light of NEP concept definition and possible early NEP flight activities.

  1. Space nuclear thermal propulsion test facilities accommodation at INEL

    Science.gov (United States)

    Hill, Thomas J.; Reed, William C.; Welland, Henry J.

    1993-01-01

    The U.S. Air Force (USAF) has proposed to develop the technology and demonstrate the feasibility of a particle bed reactor (PBR) propulsion system that could be used to power an advanced upper stage rocket engine. The U.S. Department of Energy (DOE) is cooperating with the USAF in that it would host the test facility if the USAF decides to proceed with the technology demonstration. Two DOE locations have been proposed for testing the PBR technology, a new test facility at the Nevada Test Site, or the modification and use of an existing facility at the Idaho National Engineering Laboratory. The preliminary evaluations performed at the INEL to support the PBR technology testing has been completed. Additional evaluations to scope the required changes or upgrade needed to make the proposed USAF PBR test facility meet the requirements for testing Space Exploration Initiative (SEI) nuclear thermal propulsion engines are underway.

  2. Space nuclear thermal propulsion test facilities accommodation at INEL

    International Nuclear Information System (INIS)

    Hill, T.J.; Reed, W.C.; Welland, H.J.

    1993-01-01

    The U.S. Air Force (USAF) has proposed to develop the technology and demonstrate the feasibility of a particle bed reactor (PBR) propulsion system that could be used to power an advanced upper stage rocket engine. The U.S. Department of Energy (DOE) is cooperating with the USAF in that it would host the test facility if the USAF decides to proceed with the technology demonstration. Two DOE locations have been proposed for testing the PBR technology, a new test facility at the Nevada Test Site, or the modification and use of an existing facility at the Idaho National Engineering Laboratory. The preliminary evaluations performed at the INEL to support the PBR technology testing has been completed. Additional evaluations to scope the required changes or upgrade needed to make the proposed USAF PBR test facility meet the requirements for testing Space Exploration Initiative (SEI) nuclear thermal propulsion engines are underway

  3. Feasibility of the recent Russian nuclear electric propulsion concept: 2010

    International Nuclear Information System (INIS)

    Zakirov, Vadim; Pavshook, Vladimir

    2011-01-01

    Highlights: → The paper focuses on feasibility of the Russian nuclear electric propulsion (NEP) concept. → The Russian NEP concept is based on the past experience and is, therefore, technically feasible. → The big concern is that the program will be cancelled due to non-technical issues. - Abstract: The paper introduces recent Russian nuclear electric propulsion (NEP) concept for space exploration. The concept advantages are listed along with future missions. The current development status for the two main enabling technologies is presented and the feasibility analysis of the up-to-date experience is performed. The main features of NEP concept are discussed. Revision of these features and available technologies demonstrates that the NEP concept is a logical continuation of the previous efforts by the former Soviet Union. Because no breakthrough technologies are needed for NEP development while the existing technologies only need to be adapted to the megawatt (MW) class NEP the development is considered technically feasible, low risk program likely to succeed unless cancelled by the listed non-technical reasons. Successful NEP space vehicle development is going to bring practical space exploration of solar system to the new level as well as require supplementary payload program, supporting monitoring and communication radar networks. Nuclear safety during future NEP missions can be ensured by adherence to the United Nations guidelines in the same way it was done during the Soviet Topaz Nuclear Power System (NPS) missions.

  4. Review of Nuclear Thermal Propulsion Ground Test Options

    Science.gov (United States)

    Coote, David J.; Power, Kevin P.; Gerrish, Harold P.; Doughty, Glen

    2015-01-01

    High efficiency rocket propulsion systems are essential for humanity to venture beyond the moon. Nuclear Thermal Propulsion (NTP) is a promising alternative to conventional chemical rockets with relatively high thrust and twice the efficiency of highest performing chemical propellant engines. NTP utilizes the coolant of a nuclear reactor to produce propulsive thrust. An NTP engine produces thrust by flowing hydrogen through a nuclear reactor to cool the reactor, heating the hydrogen and expelling it through a rocket nozzle. The hot gaseous hydrogen is nominally expected to be free of radioactive byproducts from the nuclear reactor; however, it has the potential to be contaminated due to off-nominal engine reactor performance. NTP ground testing is more difficult than chemical engine testing since current environmental regulations do not allow/permit open air testing of NTP as was done in the 1960's and 1970's for the Rover/NERVA program. A new and innovative approach to rocket engine ground test is required to mitigate the unique health and safety risks associated with the potential entrainment of radioactive waste from the NTP engine reactor core into the engine exhaust. Several studies have been conducted since the ROVER/NERVA program in the 1970's investigating NTP engine ground test options to understand the technical feasibility, identify technical challenges and associated risks and provide rough order of magnitude cost estimates for facility development and test operations. The options can be divided into two distinct schemes; (1) real-time filtering of the engine exhaust and its release to the environment or (2) capture and storage of engine exhaust for subsequent processing.

  5. Nuclear propulsion technology development - A joint NASA/Department of Energy project

    Science.gov (United States)

    Clark, John S.

    1992-01-01

    NASA-Lewis has undertaken the conceptual development of spacecraft nuclear propulsion systems with DOE support, in order to establish the bases for Space Exploration Initiative lunar and Mars missions. This conceptual evolution project encompasses nuclear thermal propulsion (NTP) and nuclear electric propulsion (NEP) systems. A technology base exists for NTP in the NERVA program files; more fundamental development efforts are entailed in the case of NEP, but this option is noted to offer greater advantages in the long term.

  6. Systems integration processes for space nuclear electric propulsion systems

    International Nuclear Information System (INIS)

    Olsen, C.S.; Rice, J.W.; Stanley, M.L.

    1991-01-01

    The various components and subsystems that comprise a nuclear electric propulsion system should be developed and integrated so that each functions ideally and so that each is properly integrated with the other components and subsystems in the optimum way. This paper discusses how processes similar to those used in the development and intergration of the subsystems that comprise the Multimegawatt Space Nuclear Power System concepts can be and are being efficiently and effectively utilized for these purposes. The processes discussed include the development of functional and operational requirements at the system and subsystem level; the assessment of individual nuclear power supply and thruster concepts and their associated technologies; the conduct of systems integration efforts including the evaluation of the mission benefits for each system; the identification and resolution of concepts development, technology development, and systems integration feasibility issues; subsystem, system, and technology development and integration; and ground and flight subsystem and integrated system testing

  7. Nuclear thermal propulsion transportation systems for lunar/Mars exploration

    International Nuclear Information System (INIS)

    Clark, J.S.; Borowski, S.K.; Mcilwain, M.C.; Pellaccio, D.G.

    1992-09-01

    Nuclear thermal propulsion technology development is underway at NASA and DoE for Space Exploration Initiative (SEI) missions to Mars, with initial near-earth flights to validate flight readiness. Several reactor concepts are being considered for these missions, and important selection criteria will be evaluated before final selection of a system. These criteria include: safety and reliability, technical risk, cost, and performance, in that order. Of the concepts evaluated to date, the Nuclear Engine for Rocket Vehicle Applications (NERVA) derivative (NDR) is the only concept that has demonstrated full power, life, and performance in actual reactor tests. Other concepts will require significant design work and must demonstrate proof-of-concept. Technical risk, and hence, development cost should therefore be lowest for the concept, and the NDR concept is currently being considered for the initial SEI missions. As lighter weight, higher performance systems are developed and validated, including appropriate safety and astronaut-rating requirements, they will be considered to support future SEI application. A space transportation system using a modular nuclear thermal rocket (NTR) system for lunar and Mars missions is expected to result in significant life cycle cost savings. Finally, several key issues remain for NTR's, including public acceptance and operational issues. Nonetheless, NTR's are believed to be the next generation of space propulsion systems - the key to space exploration

  8. Testing for Nuclear Thermal Propulsion Systems: Identification of Technologies for Effluent Treatment in Test Facilities

    Data.gov (United States)

    National Aeronautics and Space Administration — Key steps to ensure identification of relevant effluent treatment technologies for Nuclear Thermal Propulsion (NTP) testing include the following. 1. Review of...

  9. Smart built-in test for nuclear thermal propulsion

    International Nuclear Information System (INIS)

    Lombrozo, P.C.

    1992-03-01

    Smart built-in test (BIT) technologies are envisioned for nuclear thermal propulsion spacecraft components which undergo constant irradiation and are therefore unsafe for manual testing. Smart BIT systems of automated/remote type allow component and system tests to be conducted; failure detections are directly followed by reconfiguration of the components affected. The 'smartness' of the BIT system in question involves the reduction of sensor counts via the use of multifunction sensors, the use of components as integral sensors, and the use of system design techniques which allow the verification of system function beyond component connectivity

  10. Nuclear thermal rocket propulsion application to Mars missions

    International Nuclear Information System (INIS)

    Emrich, W.J. Jr.; Young, A.C.; Mulqueen, J.A.

    1991-01-01

    Options for vehicle configurations are reviewed in which nuclear thermal rocket (NTR) propulsion is used for a reference mission to Mars. The scenario assumes an opposition-class Mars transfer trajectory, a 435-day mission, and the use of a single nuclear engine with 75,000 lbs of thrust. Engine parameters are examined by calculating mission variables for a range of specific impulses and thrust/weight ratios. The reference mission is found to have optimal values of 925 s for the specific impulse and thrust/weight ratios of 4.0 and 0.06 for the engine and total stage ratios respectively. When the engine thrust/weight ratio is at least 4/1 the most critical engine parameter is engine specific impulse for reducing overall stage weight. In the context of this trans-Mars three-burn maneuver the NTR engine with an expander engine cycle is considered a more effective alternative than chemical/aerobrake and other propulsion options

  11. Forty years on: the UK Naval nuclear propulsion programme

    International Nuclear Information System (INIS)

    Hill, R.

    1997-01-01

    The naval nuclear power propulsion programme in the United Kingdom had its origins in the appointment of navy personnel to the Atomic Energy Research Establishment at Harwell in 1946. Atomic power was seen from the outset to be particularly applicable to submarines. It was not till 1955 that work started in earnest, however, and a naval section was established at Harwell. A land-based prototype was seen to be essential and Dounreay was selected as the site for its development. A PWR reactor system was chosen and submarine plant initial criticality by mid-1962 was the objective. However, an agreement with the USA in 1958 to use an American propulsion plant meant that it was possible to build and launch HMS Dreadnought by October 1960. Subsequent submarines were built to all-British designs and the Dounreay prototype contributed for over 35 years to their successful evolution. These submarines, which culminated in the Trafalgar class, are briefly described. In the early 1980s the decision was taken to replace the Polaris strategic weapon system by the Trident system which required a larger and more powerful submarine. The original Dounreay prototype was too small to be useful for the development of the Trident submarine and a new prototype was installed at Dounreay at the Naval Nuclear Reactor Test Establishment. (UK)

  12. Remote system for counting of nuclear pulses

    International Nuclear Information System (INIS)

    Nieves V, J.A.; Garcia H, J.M.; Aguilar B, M.A.

    1999-01-01

    In this work, it is describe technically the remote system for counting of nuclear pulses, an integral system of the project radiological monitoring in a petroleum distillation tower. The system acquires the counting of incident nuclear particles in a nuclear detector which process this information and send it in serial form, using the RS-485 toward a remote receiver, which can be a Personal computer or any other device capable to interpret the communication protocol. (Author)

  13. Overview of materials technologies for space nuclear power and propulsion

    Science.gov (United States)

    Zinkle, S. J.; Ott, L. J.; Ingersoll, D. T.; Ellis, R. J.; Grossbeck, M. L.

    2002-01-01

    A wide range of different space nuclear systems are currently being evaluated as part of the DOE Special Purpose Fission Technology program. The near-term subset of systems scheduled to be evaluated range from 50 kWe gas-, pumped liquid metal-, or liquid metal heat pipe-cooled reactors for space propulsion to 3 kWe heat pipe or pumped liquid metal systems for Mars surface power applications. The current status of the materials technologies required for the successful development of near-term space nuclear power and propulsion systems is reviewed. Materials examined in this overview include fuels (UN, UO2, UZrH), cladding and structural materials (stainless steel, superalloys, refractory alloys), neutron reflector materials (Be, BeO), and neutron shield materials (B4C,LiH). The materials technologies issues are considerably less demanding for the 3 kWe reactor systems due to lower operating temperatures, lower fuel burnup, and lower radiation damage levels. A few reactor subcomponents in the 3 kWe reactors under evaluation are being used near or above their engineering limits, which may adversely affect the 5 to 10 year lifetime design goal. It appears that most of these issues for the 3 kWe reactor systems can be accommodated by incorporating a few engineering design changes. Design limits (temperature, burnup, stress, radiation levels) for the various materials proposed for space nuclear reactors will be summarized. For example, the temperature and stress limits for Type 316 stainless steel in the 3 kWe Na-cooled heat pipe reactor (Stirling engine) concept will be controlled by thermal creep and CO2 corrosion considerations rather than radiation damage issues. Conversely, the lower operating temperature limit for the LiH shield material will likely be defined by ionizing radiation damage (radiolysis)-induced swelling, even for the relatively low radiation doses associated with the 3 kWe reactor. .

  14. Nuclear Propulsion and Power Non-Nuclear Test Facility (NP2NTF): Preliminary Analysis and Feasibility Assessment

    Data.gov (United States)

    National Aeronautics and Space Administration — Nuclear thermal propulsion (NTP) has been identified as a high NASA technology priority area by the National Research Council because nuclear thermal rockets (NTRs)...

  15. Nuclear Cryogenic Propulsion Stage (NCPS) Fuel Element Testing in the Nuclear Thermal Rocket Element Environmental Simulator (NTREES)

    Science.gov (United States)

    Emrich, William J., Jr.

    2017-01-01

    To support the on-going nuclear thermal propulsion effort, a state-of-the-art non nuclear experimental test setup has been constructed to evaluate the performance characteristics of candidate fuel element materials and geometries in representative environments. The facility to perform this testing is referred to as the Nuclear Thermal Rocket Element Environment Simulator (NTREES). Last year NTREES was successfully used to satisfy a testing milestone for the Nuclear Cryogenic Propulsion Stage (NCPS) project and met or exceeded all required objectives.

  16. Nuclear thermal propulsion technology: Results of an interagency panel in FY 1991

    International Nuclear Information System (INIS)

    Clark, J.S.; Mcdaniel, P.; Howe, S.; Helms, I.; Stanley, M.

    1993-04-01

    NASA LeRC was selected to lead nuclear propulsion technology development for NASA. Also participating in the project are NASA MSFC and JPL. The U.S. Department of Energy will develop nuclear technology and will conduct nuclear component, subsystem, and system testing at appropriate DOE test facilities. NASA program management is the responsibility of NASA/RP. The project includes both nuclear electric propulsion (NEP) and nuclear thermal propulsion (NTP) technology development. This report summarizes the efforts of an interagency panel that evaluated NTP technology in 1991. Other panels were also at work in 1991 on other aspects of nuclear propulsion, and the six panels worked closely together. The charters for the other panels and some of their results are also discussed. Important collaborative efforts with other panels are highlighted. The interagency (NASA/DOE/DOD) NTP Technology Panel worked in 1991 to evaluate nuclear thermal propulsion concepts on a consistent basis. Additionally, the panel worked to continue technology development project planning for a joint project in nuclear propulsion for the Space Exploration Initiative (SEI). Five meetings of the panel were held in 1991 to continue the planning for technology development of nuclear thermal propulsion systems. The state-of-the-art of the NTP technologies was reviewed in some detail. The major technologies identified were as follows: fuels, coatings, and other reactor technologies; materials; instrumentation, controls, health monitoring and management, and associated technologies; nozzles; and feed system technology, including turbopump assemblies

  17. An IKBS approach to surveillance for naval nuclear submarine propulsion

    International Nuclear Information System (INIS)

    Cadas, C.N.; Bowskill, J.; Mayfield, T.; Clarke, J.C.

    1995-01-01

    This Paper describes work being carried out to develop an intelligent knowledge-based system (IKBS) for use in the surveillance of naval nuclear submarine propulsion plant. In recent years, modern process plants have increased automation and installed surveillance equipment while reducing the level of manpower operating and monitoring the plant. As a result, some of the local watchkeeping tasks have been transferred to control room operators, and the data reduction and warning filtering expertise inherent in local plant operators has been lost, while an additional workload has been placed upon operators. The surveillance systems installed to date have therefore been less usable than anticipated. The solution being achieved for submarine power plant is to introduce IKBS into surveillance to replace lost expertise and return to a situation in which operators receive small amounts of high quality information rather than large amounts of low quality information. (author)

  18. An IKBS approach to surveillance for naval nuclear submarine propulsion

    International Nuclear Information System (INIS)

    Cadas, C.N.; Bowskill, J.; Mayfield, T.; Clarke, J.C.

    1993-01-01

    This paper describes work being carried out to develop an IKBS for use in surveillance of naval nuclear submarine propulsion plant. In recent years, modern process plants have increased automation and installed surveillance equipment while reducing the level of manpower operating and monitoring the plant. As a result, some of the local watchkeeping tasks have been transferred to control room operators, and the data reduction and warning filtering expertise inherent in local plant operators has been lost, while an additional workload has been placed upon operators. The surveillance systems installed to date have therefore been less usable than anticipated. The solution being achieved for submarine power plant is to introduce IKBS into surveillance to replace lost expertise, i.e. to return to a situation in which operators receive small amounts of high quality information rather than large amounts of low quality information

  19. IMPULSE---an advanced, high performance nuclear thermal propulsion system

    International Nuclear Information System (INIS)

    Petrosky, L.J.; Disney, R.K.; Mangus, J.D.; Gunn, S.A.; Zweig, H.R.

    1993-01-01

    IMPULSE is an advanced nuclear propulsion engine for future space missions based on a novel conical fuel. Fuel assemblies are formed by stacking a series of truncated (U, Zr)C cones with non-fueled lips. Hydrogen flows radially inward between the cones to a central plenum connected to a high performance bell nozzle. The reference IMPULSE engine rated at 75,000 lb thrust and 1800 MWt weighs 1360 kg and is 3.65 meters in height and 81 cm in diameter. Specific impulse is estimated to be 1000 for a 15 minute life at full power. If longer life times are required, the operating temperature can be reduced with a concomitant decrease in specific impulse. Advantages of this concept include: well defined coolant paths without outlet flow restrictions; redundant orificing; very low thermal gradients and hence, thermal stresses, across the fuel elements; and reduced thermal stresses because of the truncated conical shape of the fuel elements

  20. Integrated System Modeling for Nuclear Thermal Propulsion (NTP)

    Science.gov (United States)

    Ryan, Stephen W.; Borowski, Stanley K.

    2014-01-01

    Nuclear thermal propulsion (NTP) has long been identified as a key enabling technology for space exploration beyond LEO. From Wernher Von Braun's early concepts for crewed missions to the Moon and Mars to the current Mars Design Reference Architecture (DRA) 5.0 and recent lunar and asteroid mission studies, the high thrust and specific impulse of NTP opens up possibilities such as reusability that are just not feasible with competing approaches. Although NTP technology was proven in the Rover / NERVA projects in the early days of the space program, an integrated spacecraft using NTP has never been developed. Such a spacecraft presents a challenging multidisciplinary systems integration problem. The disciplines that must come together include not only nuclear propulsion and power, but also thermal management, power, structures, orbital dynamics, etc. Some of this integration logic was incorporated into a vehicle sizing code developed at NASA's Glenn Research Center (GRC) in the early 1990s called MOMMA, and later into an Excel-based tool called SIZER. Recently, a team at GRC has developed an open source framework for solving Multidisciplinary Design, Analysis and Optimization (MDAO) problems called OpenMDAO. A modeling approach is presented that builds on previous work in NTP vehicle sizing and mission analysis by making use of the OpenMDAO framework to enable modular and reconfigurable representations of various NTP vehicle configurations and mission scenarios. This approach is currently applied to vehicle sizing, but is extensible to optimization of vehicle and mission designs. The key features of the code will be discussed and examples of NTP transfer vehicles and candidate missions will be presented.

  1. Affordable Development and Qualification Strategy for Nuclear Thermal Propulsion

    Science.gov (United States)

    Gerrish, Harold P., Jr.; Doughty, Glen E.; Bhattacharyya, Samit K.

    2013-01-01

    A number of recent assessments have confirmed the results of several earlier studies that Nuclear Thermal Propulsion (NTP) is a leading technology for human exploration of Mars. It is generally acknowledged that NTP provides the best prospects for the transportation of humans to Mars in the 2030's. Its high Isp coupled with the high thrusts achievable, allow reasonable trip times, thereby alleviating concerns about space radiation and "claustrophobia" effects. NASA has embarked on the latest phase of the development of NTP systems, and is adopting an affordable approach in response to the pressure of the times. The affordable strategy is built on maximizing the use of the large NTP technology base developed in the 1950's and 60's. The fact that the NTP engines were actually demonstrated to work as planned, is a great risk reduction feature in its development. The strategy utilizes non-nuclear testing to the fullest extent possible, and uses focused nuclear tests for the essential qualification and certification tests. The perceived cost risk of conducting the ground tests is being addressed by considering novel testing approaches. This includes the use of boreholes to contain radioactive effluents, and use of fuel with very high retention capability for fission products. The use of prototype flight tests is being considered as final steps in the development prior to undertaking human flight missions. In addition to the technical issues, plans are being prepared to address the institutional and political issues that need to be considered in this major venture. While the development and deployment of NTP system is not expected to be cheap, the value of the system will be very high, and amortized over the many missions that it enables and enhances, the imputed costs will be very reasonable. Using the approach outlined, NASA and its partners, currently the DOE, and subsequently industry, have a good chance of creating a sustained development program leading to human

  2. Effects of nuclear electromagnetic pulse (EMP) on nuclear power plants

    International Nuclear Information System (INIS)

    Barnes, P.R.; Manweiler, R.W.; Davis, R.R.

    1977-09-01

    The electromagnetic pulse (EMP) from a high-altitude nuclear detonation consists of a transient pulse of high intensity electromagnetic fields. These intense fields induce current and voltage transients in electrical conductors. Although most nuclear power plant cables are not directly exposed to these fields, the attenuated EMP fields that propagate into the plant will couple some EMP energy to these cables. The report predicts the probable effects of the EMP transients that could be induced in critical circuits of safety-related systems. It was found that the most likely consequence of EMP for nuclear plants is an unscheduled shutdown. EMP could prolong the shutdown period by the unnecessary actuation of certain safety systems. In general, EMP could be a nuisance to nuclear power plants, but it is not considered a serious threat to plant safety

  3. Space nuclear power system and the design of the nuclear electric propulsion OTV

    International Nuclear Information System (INIS)

    Buden, D.; Garrison, P.W.

    1984-01-01

    Payload increases of three to five times that of the Shuttle/Centaur can be achieved using nuclear electric propulsion. Various nuclear power plant options being pursued by the SP-100 Program are described. These concepts can grow from 100 kW/sub e/ to 1MW/sub e/ output. Spacecraft design aspects are addressed, including thermal interactions, plume interactions, and radiation fluences. A baseline configuration is described accounting for these issues. Safety aspects of starting the OTV transfer from an altitude of 300 km indicate no significant additional risk to the biosphere

  4. Fabrication and Testing of Nuclear-Thermal Propulsion Ground Test Hardware, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Efficient nuclear-thermal propulsion requires heating a low molecular weight gas, typically hydrogen, to high temperature and expelling it through a nozzle. The...

  5. Fabrication and Testing of Nuclear-Thermal Propulsion Ground Test Hardware, Phase II, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Efficient nuclear-thermal propulsion (NTP) requires heating a low molecular weight gas, typically hydrogen, to high temperature and expelling it through a nozzle....

  6. Hydrogen Wave Heater for Nuclear Thermal Propulsion Component Testing, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA has identified Nuclear Thermal Propulsion (NTP) as an approach that can provide the fastest trip times to Mars and as the preferred concept for human space...

  7. Improved CVD Coatings for Carbide Based Nuclear Thermal Propulsion Fuel Elements, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — One of the great hurdles to further development and evaluation of nuclear thermal propulsion systems is the issue surrounding the release of radioactive material...

  8. Extreme Temperature Radiation Tolerant Instrumentation for Nuclear Thermal Propulsion Engines, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this proposal is to develop and commercialize a high reliability, high temperature smart neutron flux sensor for NASA Nuclear Thermal Propulsion...

  9. Fabrication and Testing of Nuclear-Thermal Propulsion Ground Test Hardware Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Efficient nuclear-thermal propulsion requires heating a low molecular weight gas, typically hydrogen, to high temperature and expelling it through a nozzle. The...

  10. Nuclear piston engine and pulsed gaseous core reactor power systems

    International Nuclear Information System (INIS)

    Dugan, E.T.

    1976-01-01

    The investigated nuclear piston engines consist of a pulsed, gaseous core reactor enclosed by a moderating-reflecting cylinder and piston assembly and operate on a thermodynamic cycle similar to the internal combustion engine. The primary working fluid is a mixture of uranium hexafluoride, UF 6 , and helium, He, gases. Highly enriched UF 6 gas is the reactor fuel. The helium is added to enhance the thermodynamic and heat transfer characteristics of the primary working fluid and also to provide a neutron flux flattening effect in the cylindrical core. Two and four-stroke engines have been studied in which a neutron source is the counterpart of the sparkplug in the internal combustion engine. The piston motions which have been investigated include pure simple harmonic, simple harmonic with dwell periods, and simple harmonic in combination with non-simple harmonic motion. The results of the conducted investigations indicate good performance potential for the nuclear piston engine with overall efficiencies of as high as 50 percent for nuclear piston engine power generating units of from 10 to 50 Mw(e) capacity. Larger plants can be conceptually designed by increasing the number of pistons, with the mechanical complexity and physical size as the probable limiting factors. The primary uses for such power systems would be for small mobile and fixed ground-based power generation (especially for peaking units for electrical utilities) and also for nautical propulsion and ship power

  11. Performance assessment of low pressure nuclear thermal propulsion

    Science.gov (United States)

    Gerrish, H. P., Jr.; Doughty, G. E.

    1993-01-01

    A low pressure nuclear thermal propulsion (LPNTP) system, which takes advantage of hydrogen dissociation/recombination, was proposed as a means of increasing engine specific impulse (Isp). The effect of hydrogen dissociation/recombination on LPNTP Isp is examined. A two-dimensional computer model was used to show that the optimum chamber pressure is approximately 100 psia (at a chamber temperature of 3,000 K), with an Isp approximately 15 s higher than at 1,000 psia. At high chamber temperatures and low chamber pressures, the increase in Isp is due to both lower average molecular weights caused by dissociation and added kinetic energy from monatomic hydrogen recombination. Monatomic hydrogen recombination increases the Isp more then hydrogen dissociation. Variations in the mole fraction of monatomic hydrogen are similar to variations in static pressure along the axial nozzle position. Most recombination occurs close to the nozzle throat. Practical variations in nozzle geometry have minimal impact on recombination. Other models which can simulate a wider range of nozzle designs should be used in the future. The uncertainty of the hydrogen kinetic reaction rates at high temperatures (approximately 3,000 K) affects the accuracy of the analysis and should be verified with simple bench tests.

  12. Innovative nuclear thermal propulsion technology evaluation: Results of the NASA/DOE Task Team study

    International Nuclear Information System (INIS)

    Howe, S.; Borowski, S.; Helms, I.; Diaz, N.; Anghaie, S.; Latham, T.

    1991-01-01

    In response to findings from two NASA/DOE nuclear propulsion workshops held in the summer of 1990, six task teams were formed to continue evaluation of various nuclear propulsion concepts. The Task Team on Nuclear Thermal Propulsion (NTP) created the Innovative Concepts Subpanel to evaluate thermal propulsion concepts which did not utilize solid fuel. The Subpanel endeavored to evaluate each of the concepts on a ''level technological playing field,'' and to identify critical technologies, issues, and early proof-of-concept experiments. The concepts included the liquid core fission, the gas core fission, the fission foil reactors, explosively driven systems, fusion, and antimatter. The results of the studies by the panel will be provided. 13 refs., 6 figs., 2 tabs

  13. NSPWG-recommended safety requirements and guidelines for SEI nuclear propulsion

    International Nuclear Information System (INIS)

    Marshall, A.C.; Lee, J.H.; McCulloch, W.H.; Sawyer, J.C. Jr.; Bari, R.A.; Brown, N.W.; Cullingford, H.S.; Hardy, A.C.; Remp, K.; Sholtis, J.A.

    1992-01-01

    An Interagency Nuclear Safety Policy Working Group (NSPWG) was chartered to recommend nuclear safety policy, requirements, and guidelines for the Space Exploration Initiative (SEI) nuclear propulsion program to facilitate the implementation of mission planning and conceptual design studies. The NSPWG developed a top- level policy to provide the guiding principles for the development and implementation of the nuclear propulsion safety program and the development of Safety Functional Requirements. In addition the NSPWG reviewed safety issues for nuclear propulsion and recommended top-level safety requirements and guidelines to address these issues. Safety requirements were developed for reactor start-up, inadvertent criticality, radiological release and exposure, disposal, entry, and safeguards. Guidelines were recommended for risk/reliability, operational safety, flight trajectory and mission abort, space debris and meteoroids, and ground test safety. In this paper the specific requirements and guidelines will be discussed

  14. A pulse amplitude dividing circuit for nuclear applications

    International Nuclear Information System (INIS)

    Ediss, C.; McQuarrie, S.A.

    1981-01-01

    A pulse dividing circuit has been developed to provide analogue and digital outputs proportional to the ratio of the amplitudes of two nuclear pulses. Input pulses ranging from 200 mV to 10 V may be processed by the device. The pulse dividing circuit has been successfully incorporated as part of a small gamma camera. (orig.)

  15. Nuclear Propulsion through Direct Conversion of Fusion Energy

    Data.gov (United States)

    National Aeronautics and Space Administration — The future of manned space exploration and development of space depends critically on the creation of a vastly more efficient propulsion architecture for in-space...

  16. NASA safety program activities in support of the Space Exploration Initiatives Nuclear Propulsion program

    Science.gov (United States)

    Sawyer, J. C., Jr.

    1993-01-01

    The activities of the joint NASA/DOE/DOD Nuclear Propulsion Program Technical Panels have been used as the basis for the current development of safety policies and requirements for the Space Exploration Initiatives (SEI) Nuclear Propulsion Technology development program. The Safety Division of the NASA Office of Safety and Mission Quality has initiated efforts to develop policies for the safe use of nuclear propulsion in space through involvement in the joint agency Nuclear Safety Policy Working Group (NSPWG), encouraged expansion of the initial policy development into proposed programmatic requirements, and suggested further expansion into the overall risk assessment and risk management process for the NASA Exploration Program. Similar efforts are underway within the Department of Energy to ensure the safe development and testing of nuclear propulsion systems on Earth. This paper describes the NASA safety policy related to requirements for the design of systems that may operate where Earth re-entry is a possibility. The expected plan of action is to support and oversee activities related to the technology development of nuclear propulsion in space, and support the overall safety and risk management program being developed for the NASA Exploration Program.

  17. Introduction to the 'CAS' nuclear propulsion plant for ships: specific safety options

    International Nuclear Information System (INIS)

    Verdeau, J.J.; Baujat, J.

    1978-01-01

    After a brief review of the development of nuclear propulsion in FRANCE (Land Based Prototype PAT 1964 - Navy nuclear ships - Advanced Nuclear Boiler Prototype CAP 1975 and now the CAS nuclear plant), the specific safety options of CAS are presented: cold, compartmented fuel (plates); reduced flow during LOCA; permanent cooling of fuel during LOCA; pressurized, entirely passive containment; no control rod ejection and possibility of temporary storage of spent fuel on board [fr

  18. A review of the Los Alamos effort in the development of nuclear rocket propulsion

    International Nuclear Information System (INIS)

    Durham, F.P.; Kirk, W.L.; Bohl, R.J.

    1991-01-01

    This paper reviews the achievements of the Los Alamos nuclear rocket propulsion program and describes some specific reactor design and testing problems encountered during the development program along with the progress made in solving these problems. The relevance of these problems to a renewed nuclear thermal rocket development program for the Space Exploration Initiative (SEI) is discussed. 11 figs

  19. Structural Dynamics of a Pulsed-Jet Propulsion System for Underwater Soft Robots

    Directory of Open Access Journals (Sweden)

    Federico Renda

    2015-06-01

    Full Text Available This paper entails the study of the pulsed-jet propulsion inspired by cephalopods in the frame of underwater bioinspired robotics. This propulsion routine involves a sequence of consecutive cycles of inflation and collapse of an elastic bladder, which, in the robotics artefact developed by the authors, is enabled by a cable-driven actuation of a deformable shell composed of rubber-like materials. In the present work an all-comprehensive formulation is derived by resorting to a coupled approach that comprises of a model of the structural dynamics of the cephalopod-like elastic bladder and a model of the pulsed-jet thrust production. The bladder, or mantle, is modelled by means of geometrically exact, axisymmetric, nonlinear shell theory, which yields an accurate estimation of the forces involved in driving the deformation of the structure in water. By coupling these results with those from a standard thrust model, the behaviour of the vehicle propelling itself in water is derived. The constitutive laws of the shell are also exploited as control laws with the scope of replicating the muscle activation routine observed in cephalopods. The model is employed to test various shapes, material properties and actuation routines of the mantle. The results are compared in terms of speed performance in order to identify suitable design guidelines. Altogether, the model is tested in more than 50 configurations, eventually providing useful insight for the development of more advanced vehicles and bringing evidence of its reliability in studying the dynamics of both man-made cephalopod-inspired robots and live specimens.

  20. S100 lathe bed pulse generator applied to pulsed nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Cernicchiaro, G.R.C.; Rudge, M.G.; Albuquerque, M.P.

    1989-01-01

    The project and construction of four channel pulse generator in the S100 standard plate and its control software for microcomputer are described. The microcomputer has total control on the pulse generator, which has seven programable parameters, defining the position of four pulses and the width for the three first ones. This pulse generator is controlled by a software developed in c language, and is used in pulsed nuclear magnetic resonance experiences. (M.C.K.) [pt

  1. Application of Recommended Design Practices for Conceptual Nuclear Fusion Space Propulsion Systems

    Science.gov (United States)

    Williams, Craig H.

    2004-01-01

    An AIAA Special Project Report was recently produced by AIAA's Nuclear and Future Flight Propulsion Technical Committee and is currently in peer review. The Report provides recommended design practices for conceptual engineering studies of nuclear fusion space propulsion systems. Discussion and recommendations are made on key topics including design reference missions, degree of technological extrapolation and concomitant risk, thoroughness in calculating mass properties (nominal mass properties, weight-growth contingency and propellant margins, and specific impulse), and thoroughness in calculating power generation and usage (power-flow, power contingencies, specific power). The report represents a general consensus of the nuclear fusion space propulsion system conceptual design community and proposes 15 recommendations. This paper expands on the Report by providing specific examples illustrating how to apply each of the recommendations.

  2. Small Reactor Designs Suitable for Direct Nuclear Thermal Propulsion: Interim Report

    Energy Technology Data Exchange (ETDEWEB)

    Bruce G. Schnitzler

    2012-01-01

    Advancement of U.S. scientific, security, and economic interests requires high performance propulsion systems to support missions beyond low Earth orbit. A robust space exploration program will include robotic outer planet and crewed missions to a variety of destinations including the moon, near Earth objects, and eventually Mars. Past studies, in particular those in support of both the Strategic Defense Initiative (SDI) and the Space Exploration Initiative (SEI), have shown nuclear thermal propulsion systems provide superior performance for high mass high propulsive delta-V missions. In NASA's recent Mars Design Reference Architecture (DRA) 5.0 study, nuclear thermal propulsion (NTP) was again selected over chemical propulsion as the preferred in-space transportation system option for the human exploration of Mars because of its high thrust and high specific impulse ({approx}900 s) capability, increased tolerance to payload mass growth and architecture changes, and lower total initial mass in low Earth orbit. The recently announced national space policy2 supports the development and use of space nuclear power systems where such systems safely enable or significantly enhance space exploration or operational capabilities. An extensive nuclear thermal rocket technology development effort was conducted under the Rover/NERVA, GE-710 and ANL nuclear rocket programs (1955-1973). Both graphite and refractory metal alloy fuel types were pursued. The primary and significantly larger Rover/NERVA program focused on graphite type fuels. Research, development, and testing of high temperature graphite fuels was conducted. Reactors and engines employing these fuels were designed, built, and ground tested. The GE-710 and ANL programs focused on an alternative ceramic-metallic 'cermet' fuel type consisting of UO2 (or UN) fuel embedded in a refractory metal matrix such as tungsten. The General Electric program examined closed loop concepts for space or terrestrial

  3. Results of the qualification test campaign of a Pulsed Plasma Thruster for Cubesat Propulsion (PPTCUP)

    Science.gov (United States)

    Ciaralli, S.; Coletti, M.; Gabriel, S. B.

    2016-04-01

    Pulsed Plasma Thruster for Cubesat Propulsion (PPTCUP) is an ablative pulsed plasma thruster designed with the aim of providing translational and orbital control to Cubesat platforms. The qualification model presented in this paper has been developed by Mars Space Ltd, Clyde Space Ltd and the University of Southampton to produce a versatile ;stand-alone; module that can be bolted on the Cubesat structure, allowing the orbital control along the X or Y-axis of the satellite. An extensive and complete test campaign to qualify the unit for space flight, which includes electromagnetic compatibility (EMC) characterization, thermal cycling and mechanical tests, has been performed according to the NASA GEVS procedures. PPTCUP is characterized by an averaged specific impulse of 655±58 s and a deliverable total impulse of 48.2±4.2 Ns. Finally, it has been found that the unit is compliant with the EMC requirements and can successfully withstand the thermal and mechanical loads typical of a Cubesat space mission.

  4. RSMASS-D nuclear thermal propulsion and bimodal system mass models

    Science.gov (United States)

    King, Donald B.; Marshall, Albert C.

    1997-01-01

    Two relatively simple models have been developed to estimate reactor, radiation shield, and balance of system masses for a particle bed reactor (PBR) nuclear thermal propulsion concept and a cermet-core power and propulsion (bimodal) concept. The approach was based on the methodology developed for the RSMASS-D models. The RSMASS-D approach for the reactor and shield sub-systems uses a combination of simple equations derived from reactor physics and other fundamental considerations along with tabulations of data from more detailed neutron and gamma transport theory computations. Relatively simple models are used to estimate the masses of other subsystem components of the nuclear propulsion and bimodal systems. Other subsystem components include instrumentation and control (I&C), boom, safety systems, radiator, thermoelectrics, heat pipes, and nozzle. The user of these models can vary basic design parameters within an allowed range to achieve a parameter choice which yields a minimum mass for the operational conditions of interest. Estimated system masses are presented for a range of reactor power levels for propulsion for the PBR propulsion concept and for both electrical power and propulsion for the cermet-core bimodal concept. The estimated reactor system masses agree with mass predictions from detailed calculations with xx percent for both models.

  5. Versatile pulse programmer for pulsed nuclear magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Adduci, D.J.

    1979-05-01

    A description of the sequence of events and the decisions leading to the design of a versatile pulse programmer for pulsed NMR are presented. Background and application information is discussed in order that the reader might better understand the role of the pulse programmer in a NMR spectrometer. Various other design approaches are presented as a basis for comparison. Specifications for this design are proposed, the hardware implementation of the specifications is discussed, and the software operating system is presented.

  6. Versatile pulse programmer for pulsed nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Adduci, D.J.

    1979-05-01

    A description of the sequence of events and the decisions leading to the design of a versatile pulse programmer for pulsed NMR are presented. Background and application information is discussed in order that the reader might better understand the role of the pulse programmer in a NMR spectrometer. Various other design approaches are presented as a basis for comparison. Specifications for this design are proposed, the hardware implementation of the specifications is discussed, and the software operating system is presented

  7. Summary and recommendations on nuclear electric propulsion technology for the space exploration initiative

    Science.gov (United States)

    Doherty, Michael P.; Holcomb, Robert S.

    1993-01-01

    A project in Nuclear Electric Propulsion (NEP) technology is being established to develop the NEP technologies needed for advanced propulsion systems. A paced approach has been suggested which calls for progressive development of NEP component and subsystem level technologies. This approach will lead to major facility testing to achieve TRL-5 for megawatt NEP for SEI mission applications. This approach is designed to validate NEP power and propulsion technologies from kilowatt class to megawatt class ratings. Such a paced approach would have the benefit of achieving the development, testing, and flight of NEP systems in an evolutionary manner. This approach may also have the additional benefit of synergistic application with SEI extraterrestrial surface nuclear power applications.

  8. Direct Energy Conversion for Nuclear Propulsion at Low Specific Mass

    Science.gov (United States)

    Scott, John H.

    2014-01-01

    The project will continue the FY13 JSC IR&D (October-2012 to September-2013) effort in Travelling Wave Direct Energy Conversion (TWDEC) in order to demonstrate its potential as the core of a high potential, game-changing, in-space propulsion technology. The TWDEC concept converts particle beam energy into radio frequency (RF) alternating current electrical power, such as can be used to heat the propellant in a plasma thruster. In a more advanced concept (explored in the Phase 1 NIAC project), the TWDEC could also be utilized to condition the particle beam such that it may transfer directed kinetic energy to a target propellant plasma for the purpose of increasing thrust and optimizing the specific impulse. The overall scope of the FY13 first-year effort was to build on both the 2012 Phase 1 NIAC research and the analysis and test results produced by Japanese researchers over the past twenty years to assess the potential for spacecraft propulsion applications. The primary objective of the FY13 effort was to create particle-in-cell computer simulations of a TWDEC. Other objectives included construction of a breadboard TWDEC test article, preliminary test calibration of the simulations, and construction of first order power system models to feed into mission architecture analyses with COPERNICUS tools. Due to funding cuts resulting from the FY13 sequestration, only the computer simulations and assembly of the breadboard test article were completed. The simulations, however, are of unprecedented flexibility and precision and were presented at the 2013 AIAA Joint Propulsion Conference. Also, the assembled test article will provide an ion current density two orders of magnitude above that available in previous Japanese experiments, thus enabling the first direct measurements of power generation from a TWDEC for FY14. The proposed FY14 effort will use the test article for experimental validation of the computer simulations and thus complete to a greater fidelity the

  9. Rising time restoration for nuclear pulse using a mathematic model.

    Science.gov (United States)

    Wang, Min; Hong, Xu; Zhou, Jian-Bin; Liu, Ying; Fei, Peng; Wan, Wen-Jie; Zhou, Wei; Ma, Ying-Jie; Liu, Yi; Ding, Wei-Cheng

    2018-01-17

    The rising time of a nuclear pulse is slowed before being digitized because of the effect of distributed capacitance and resistance. This results in the waveform distortion of a shaped pulse. In this study, the effect of distributed capacitance and resistance is equivalent to the result of RC network. The mathematical model of the network is established to restore the rising time of the input nuclear pulse. Experimental results show that the leading edge of the nuclear pulse becomes steep after rising time restoration, and the shape of the shaped pulse is also improved. The energy spectrum obtained with rising time restoration is compared with that without rising time restoration. The comparison result indicates that using rising time restoration can extend the measurement range of pulse amplitude without affecting the energy resolution of the system. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Aircraft Nuclear Propulsion Project Quarterly Progress Report for Period Ending December 31, 1956

    Energy Technology Data Exchange (ETDEWEB)

    NA, NA [ORNL

    1957-03-12

    This quarterly progress report of the Aircraft Nuclear Propulsion Project at ORNL records the technical progress of research on circulating-fuel reactors and other ANP research at the Laboratory. The report is divided into five major parts: 1) Aircraft Reactor Engineering, 2) Chemistry, and 3) Metallurgy, 4) Heat Transfer and Physical Properties, Radiation Damage, and Fuel Recovery and Reprocessing, and 5) Reactor Shielding.

  11. Nuclear electric propulsion: A better, safer, cheaper transportation system for human exploration of Mars

    International Nuclear Information System (INIS)

    Clark, J.S.; George, J.A.; Gefert, L.P.; Doherty, M.P.; Sefcik, R.J.

    1994-03-01

    NASA has completed a preliminary mission and systems study of nuclear electric propulsion (NEP) systems for 'split-sprint' human exploration and related robotic cargo missions to Mars. This paper describes the study, the mission architecture selected, the NEP system and technology development needs, proposed development schedules, and estimated development costs. Since current administration policy makers have delayed funding for key technology development activities that could make Mars exploration missions a reality in the near future, NASA will have time to evaluate various alternate mission options, and it appears prudent to ensure that Mars mission plans focus on astronaut and mission safety, while reducing costs to acceptable levels. The split-sprint nuclear electric propulsion system offers trip times comparable to nuclear thermal propulsion (NTP) systems, while providing mission abort opportunities that are not possible with 'reference' mission architectures. Thus, NEP systems offer short transit times for the astronauts, reducing the exposure of the crew to intergalactic cosmic radiation. The high specific impulse of the NEP system, which leads to very low propellant requirements, results in significantly lower 'initial mass in low earth orbit' (IMLEO). Launch vehicle packaging studies show that the NEP system can be launched, assembled, and deployed, with about one less 240-metric-ton heavy lift launch vehicle (HLLV) per mission opportunity - a very Technology development cost of the nuclear reactor for an NEP system would be shared with the proposed nuclear surface power systems, since nuclear systems will be required to provide substantial electrical power on the surface of Mars. The NEP development project plan proposed includes evolutionary technology development for nuclear electric propulsion systems that expands upon SP-100 (Space Power - 100 kw(e)) technology that has been developed for lunar and Mars surface nuclear power

  12. Blazing the trailway: Nuclear electric propulsion and its technology program plans

    Science.gov (United States)

    Doherty, Michael P.

    1992-01-01

    An overview is given of the plans for a program in nuclear electric propulsion (NEP) technology for space applications being considered by NASA, DOE, and DOD. Possible missions using NEP are examined, and NEP technology plans are addressed regarding concept development, systems engineering, nuclear fuels, power conversion, thermal management, power management and distribution, electric thrusters, facilities, and issues related to safety and environment. The programmatic characteristics are considered.

  13. Nuclear electric propulsion: A better, safer, cheaper transportation system for human exploration of Mars

    Science.gov (United States)

    Clark, John S.; George, Jeffrey A.; Gefert, Leon P.; Doherty, Michael P.; Sefcik, Robert J.

    1994-01-01

    NASA has completed a preliminary mission and systems study of nuclear electric propulsion (NEP) systems for 'split-sprint' human exploration and related robotic cargo missions to Mars. This paper describes the study, the mission architecture selected, the NEP system and technology development needs, proposed development schedules, and estimated development costs. Since current administration policy makers have delayed funding for key technology development activities that could make Mars exploration missions a reality in the near future, NASA will have time to evaluate various alternate mission options, and it appears prudent to ensure that Mars mission plans focus on astronaut and mission safety, while reducing costs to acceptable levels. The split-sprint nuclear electric propulsion system offers trip times comparable to nuclear thermal propulsion (NTP) systems, while providing mission abort opportunities that are not possible with 'reference' mission architectures. Thus, NEP systems offer short transit times for the astronauts, reducing the exposure of the crew to intergalactic cosmic radiation. The high specific impulse of the NEP system, which leads to very low propellant requirements, results in significantly lower 'initial mass in low earth orbit' (IMLEO). Launch vehicle packaging studies show that the NEP system can be launched, assembled, and deployed, with about one less 240-metric-ton heavy lift launch vehicle (HLLV) per mission opportunity - a very Technology development cost of the nuclear reactor for an NEP system would be shared with the proposed nuclear surface power systems, since nuclear systems will be required to provide substantial electrical power on the surface of Mars. The NEP development project plan proposed includes evolutionary technology development for nuclear electric propulsion systems that expands upon SP-100 (Space Power - 100 kw(e)) technology that has been developed for lunar and Mars surface nuclear power, and small NEP systems

  14. Blazing the trailway - Nuclear electric propulsion and its technology program plans

    Science.gov (United States)

    Doherty, Michael P.

    1991-01-01

    An overview is given of the plans for a program in nuclear electric propulsion (NEP) technology for outer space applications being considered by NASA, DOE, and DOD. Possible missions using NEP are examined, and NEP technology plans are addressed regarding concept development, systems engineering, nuclear fuels, power conversion, thermal management, power management and distribution, electric thrusters, facilities, and issues related to safety and environment. The programmatic characteristics are considered.

  15. Naval nuclear propulsion and the international nonproliferation regime

    International Nuclear Information System (INIS)

    Guimaraes, Leonam dos Santos

    2005-01-01

    Nuclear powered attack submarine (SSN) acquisition by Non-Proliferation Treaty No- Nuclear Weapon State (NPT-NNWS) Navies does not imply nuclear weapon proliferation risks higher than those related to stationary research and power reactors. It must then be recognized that stringent restraints on supplies and political pressures on governments, both exercised very effectively by No-Proliferation Treaty - Nuclear Weapon State (NPT-NWS) against NPT-NNWS indigenous development of SSN and associated fuel cycle facilities, are fundamentally based on geopolitical and military strategic objectives. This practice is far from being related exclusively to the NPT spirit: in fact, it is a matter of freedom at seas and not of nuclear proliferation. (author)

  16. Nuclear Propulsion through Direct Conversion of Fusion Energy: The Fusion Driven Rocket

    Science.gov (United States)

    Slough, John; Pancotti, Anthony; Kirtley, David; Pihl, Christopher; Pfaff, Michael

    2012-01-01

    The future of manned space exploration and development of space depends critically on the creation of a dramatically more proficient propulsion architecture for in-space transportation. A very persuasive reason for investigating the applicability of nuclear power in rockets is the vast energy density gain of nuclear fuel when compared to chemical combustion energy. Current nuclear fusion efforts have focused on the generation of electric grid power and are wholly inappropriate for space transportation as the application of a reactor based fusion-electric system creates a colossal mass and heat rejection problem for space application.

  17. An Economical Fast Discriminator for Nuclear Pulse Counting

    International Nuclear Information System (INIS)

    Issarachai, Opas; Punnachaiya, Suvit

    2009-07-01

    Full text: This research work was aimed to develop a fast discriminator at low cost but high capability for discrimination a nanosecond nuclear pulse. The fast discriminator can be used in association with fast photon counting system. The designed structure consisted of the ultra-fast voltage comparator using ADCMP601 integrated circuit, the monostable multivibrator with controllable pulse width output by propagation delay of logic gate, and the fast response buffer amplifier. The tested results of pulse height discrimination of 0-5 V nuclear pulse with 20 ns (FWHM) pulse width showed the correlation coefficient (R 2 ) between discrimination level and pulse height was 0.998, while the pulse rate more than 10 MHz could be counted. The 30 ns logic pulse width output revealed high stable and could be smoothly driven to low impedance load at 50 Ω. For pulse signal transmission to the counter, it was also found that the termination of reflected signal must be considered because it may cause pulse counting error

  18. Pulse shaping amplifier (PSA) for nuclear spectroscopy system

    International Nuclear Information System (INIS)

    Lombigit, L.; Maslina Mohd Ibrahim; Nolida Yusup; Nur Aira Abdul Rahman; Yong, C.F.

    2014-01-01

    Pulse Shaping Amplifier (PSA) is an essential components in nuclear spectroscopy system. This networks have two functions; to shape the output pulse and performs noise filtering. In this paper, we describes procedure for design and development of a pulse shaping amplifier which can be used for nuclear spectroscopy system. This prototype was developed using high performance electronics devices and assembled on a FR4 type printed circuit board. Performance of this prototype was tested by comparing it with an equivalent commercial spectroscopy amplifier (Model SILENA 7611). The test results show that the performance of this prototype is comparable to the commercial spectroscopic amplifier. (author)

  19. NERVA-Derived Nuclear Thermal Propulsion Dual Mode Operation

    Science.gov (United States)

    Zweig, Herbert R.; Hundal, Rolv

    1994-07-01

    Generation of electrical power using the nuclear heat source of a NERVA-derived nuclear thermal rocket engine is presented. A 111,200 N thrust engine defined in a study for NASA-LeRC in FY92 is the reference engine for a three-engine vehicle for which a 50 kWe capacity is required. Processes are described for energy extraction from the reactor and for converting the energy to electricity. The tie tubes which support the reactor fuel elements are the source of thermal energy. The study focuses on process systems using Stirling cycle energy conversion operating at 980 K and an alternate potassium-Rankine system operating at 1,140 K. Considerations are given of the effect of the power production on turbopump operation, ZrH moderator dissociation, creep strain in the tie tubes, hydrogen permeation through the containment materials, requirements for a backup battery system, and the effects of potential design changes on reactor size and criticality. Nuclear considerations include changing tie tube materials to TZM, changing the moderator to low vapor-pressure yttrium hydride, and changing the fuel form from graphite matrix to a carbon-carbide composite.

  20. Nuclear thermal propulsion engine based on particle bed reactor using light water steam as a propellant

    Science.gov (United States)

    Powell, James R.; Ludewig, Hans; Maise, George

    1993-01-01

    In this paper the possibility of configuring a water cooled Nuclear Thermal Propulsion (NTP) rocket, based on a Particle Bed Reactor (PBR) is investigated. This rocket will be used to operate on water obtained from near earth objects. The conclusions reached in this paper indicate that it is possible to configure a PBR based NTP rocket to operate on water and meet the mission requirements envisioned for it. No insurmountable technology issues have been identified.

  1. Nuclear electric propulsion mission engineering study development program and costs estimates, Phase 2 review

    Science.gov (United States)

    1972-01-01

    The results are presented of the second six-month performance period of the Nuclear Electric Propulsion Mission Engineering Study. A brief overview of the program, identifying the study objectives and approach, and a discussion of the program status and schedule are presented. The program results are reviewed and key conclusions to date are summarized. Planned effort for the remainder of the program is reviewed.

  2. Reactivity variation's analysis in nuclear propulsion considering the operational real conditions requirements

    Energy Technology Data Exchange (ETDEWEB)

    Pires, Leonardo Paredes; Santos, Rubens Souza dos; Lapa, Marcelo Franklin, E-mail: leonardo_paredes@icloud.com, E-mail: lapa@ien.gov.br, E-mail: rsantos@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    The work presented in this paper highlights the need for the study to determine the reactivity variation ramps needed and possible to meet the real operational conditions required by a nuclear submarine in this several operating phases. In accordance with the operational needs and necessary maneuvers in certain tactical situations, large power variations in the propulsion are demanded. As these sudden and severe changes in propulsion come from the thermal power of nuclear origin, the operation of the nuclear island has to know what kind of answers and criticality variations are necessary to meet each demand speed required. It should be noted that these criticality inserts are conditioned, not only by the propulsion needs, but fundamentally by the imperative need to ensure the core integrity and the chain reaction sustainability considering the phenomenons and complex effects, nonlinear and retro-fed involved. It has to be determined what is the past and required time for each criticality insertion is perceived as motor power. Considering the highlighted aspects, this article concludes and indicates to its end, the need to establish a base operating transitional agenda, according to the naval combat doctrine, to be tested and analyzed under the aspects and peculiarities of kinetic reactors, with the purpose of being generated the appropriate criticality curves for each real need and their respective times of anticipated action. (author)

  3. Multiphysics Modeling of a Single Channel in a Nuclear Thermal Propulsion Grooved Ring Fuel Element

    Science.gov (United States)

    Kim, Tony; Emrich, William J., Jr.; Barkett, Laura A.; Mathias, Adam D.; Cassibry, Jason T.

    2013-01-01

    In the past, fuel rods have been used in nuclear propulsion applications. A new fuel element concept that reduces weight and increases efficiency uses a stack of grooved discs. Each fuel element is a flat disc with a hole on the interior and grooves across the top. Many grooved ring fuel elements for use in nuclear thermal propulsion systems have been modeled, and a single flow channel for each design has been analyzed. For increased efficiency, a fuel element with a higher surface-area-to-volume ratio is ideal. When grooves are shallower, i.e., they have a lower surface area, the results show that the exit temperature is higher. By coupling the physics of turbulence with those of heat transfer, the effects on the cooler gas flowing through the grooves of the thermally excited solid can be predicted. Parametric studies were done to show how a pressure drop across the axial length of the channels will affect the exit temperatures of the gas. Geometric optimization was done to show the behaviors that result from the manipulation of various parameters. Temperature profiles of the solid and gas showed that more structural optimization is needed to produce the desired results. Keywords: Nuclear Thermal Propulsion, Fuel Element, Heat Transfer, Computational Fluid Dynamics, Coupled Physics Computations, Finite Element Analysis

  4. Technological requirements of nuclear electric propulsion systems for fast Earth-Mars transfers

    Science.gov (United States)

    Bérend, N.; Epenoy, R.; Cliquet, E.; Laurent-Varin, J.; Avril, S.

    2013-03-01

    Recent advances in electric propulsion technologies such as magnetoplasma rockets gave a new momentum to the study of nuclear electric propulsion concepts for Mars missions. Some recent works have been focused on very short Earth-to-Mars transfers of about 40 days with high-power, variable specific impulse propulsion systems [1]. While the interest of nuclear electric propulsion appears clearly with regard to the payload mass ratio (due to a high level of specific impulse), its interest with regard to the transfer time is more complex to define, as it depends on many design parameters. In this paper, a general analysis of the capability of nuclear electric propulsion systems considering both criteria (the payload mass ratio and the transfer time) is performed, and the technological requirements for fast Earth-Mars transfers are studied. This analysis has been performed in two steps. First, complete trajectory optimizations have been performed by CNES-DCT in order to obtain the propulsion requirements of the mission for different technological hypotheses regarding the engine technology (specific impulse levels and the throttling capability) and different mission requirements. The methodology used for designing fuel-optimal heliocentric trajectories, based on the Pontryagin's Maximum Principle will be presented. Trajectories have been computed for various power levels combined with either variable or fixed Isp. The second step consisted in evaluating a simpler method that could easily link the main mission requirements (the transfer time and the payload fraction) to the main technological requirements (the specific mass of the power generation system and the structure mass ratio of the whole vehicle, excluding the power generation system). Indeed, for power-limited systems, propulsion requirements can be characterized through the "trajectory characteristic" parameter, defined as the integral over time of the squared thrust acceleration. Technological requirements for

  5. Study of a Tricarbide Grooved Ring Fuel Element for Nuclear Thermal Propulsion

    Science.gov (United States)

    Taylor, Brian; Emrich, Bill; Tucker, Dennis; Barnes, Marvin; Donders, Nicolas; Benensky, Kelsa

    2018-01-01

    Deep space exploration, especially that of Mars, is on the horizon as the next big challenge for space exploration. Nuclear propulsion, through which high thrust and efficiency can be achieved, is a promising option for decreasing the cost and logistics of such a mission. Work on nuclear thermal engines goes back to the days of the NERVA program. Currently, nuclear thermal propulsion is under development again in various forms to provide a superior propulsion system for deep space exploration. The authors have been working to develop a concept nuclear thermal engine that uses a grooved ring fuel element as an alternative to the traditional hexagonal rod design. The authors are also studying the use of carbide fuels. The concept was developed in order to increase surface area and heat transfer to the propellant. The use of carbides would also raise the operating temperature of the reactor. It is hoped that this could lead to a higher thrust to weight nuclear thermal engine. This paper describes the modeling of neutronics, heat transfer, and fluid dynamics of this alternative nuclear fuel element geometry. Fabrication experiments of grooved rings from carbide refractory metals are also presented along with material characterization and interactions with a hot hydrogen environment. Results of experiments and associated analysis are discussed. The authors demonstrated success in reaching desired densities with some success in material distribution and reaching a solid solution. Future work is needed to improve distribution of material, minimize oxidation during the milling process, and define a fabrication process that will serve for constructing grooved ring fuel rods for large system tests.

  6. Use of simulators for the continuation training of nuclear propulsion plant operators in the Royal Navy

    International Nuclear Information System (INIS)

    Burbridge, A.J.H.

    1985-01-01

    The Royal Navy now operates 17 submarines which are powered by Pressurised Water Reactors. In the training of the operators of these Nuclear Propulsion Plants, computer simulation is used widely, and ranges from simple analogue devices which present the dynamic response of single plant parameters, through more complex hybrid computers which allow some operator interaction, to the real-time full simulation Manoeuvring Room Trainers. This paper provides information on the use of this latter equipment for the Continuation Training of the Manoeuvring Room Watchkeepers of the Royal Navy's nuclear powered submarines. (author)

  7. Finite-thrust optimization of interplanetary transfers of space vehicle with bimodal nuclear thermal propulsion

    Science.gov (United States)

    Kharytonov, Oleksii M.; Kiforenko, Boris M.

    2011-08-01

    The nuclear thermal rocket (NTR) propulsion is one of the leading promising technologies for primary space propulsion for manned exploration of the solar system due to its high specific impulse capability and sufficiently high thrust-to-weight ratio. Another benefit of NTR is its possible bimodal design, when nuclear reactor is used for generation of a jet thrust in a high-thrust mode and (with an appropriate power conversion system) as a source of electric power to supply the payload and the electric engines in a low-thrust mode. The model of the NTR thrust control was developed considering high-thrust NTR as a propulsion system of limited power and exhaust velocity. For the proposed model the control of the thrust value is accomplished by the regulation of reactor thermal power and propellant mass flow rate. The problem of joint optimization of the combination of high- and low-thrust arcs and the parameters of bimodal NTR (BNTR) propulsion system is considered for the interplanetary transfers. The interplanetary trajectory of the space vehicle is formed by the high-thrust NTR burns, which define planet-centric maneuvers and by the low-thrust heliocentric arcs where the nuclear electric propulsion (NEP) is used. The high-thrust arcs are analyzed using finite-thrust approach. The motion of the corresponding dynamical system is realized in three phase spaces concerning the departure planet-centric maneuver by means of high-thrust NTR propulsion, the low-thrust NEP heliocentric maneuver and the approach high-thrust NTR planet-centric maneuver. The phase coordinates are related at the time instants of the change of the phase spaces due to the relations between the space vehicle masses. The optimal control analysis is performed using Pontryagin's maximum principle. The numerical results are analyzed for Earth-Mars "sprint" transfer. The optimal values of the parameters that define the masses of NTR and NEP subsystems have been evaluated. It is shown that the low

  8. Gas Foil Bearings for Space Propulsion Nuclear Electric Power Generation

    Science.gov (United States)

    Howard, Samuel A.; DellaCorte, Christopher

    2006-01-01

    The choice of power conversion technology is critical in directing the design of a space vehicle for the future NASA mission to Mars. One candidate design consists of a foil bearing supported turbo alternator driven by a helium-xenon gas mixture heated by a nuclear reactor. The system is a closed-loop, meaning there is a constant volume of process fluid that is sealed from the environment. Therefore, foil bearings are proposed due to their ability to use the process gas as a lubricant. As such, the rotor dynamics of a foil bearing supported rotor is an important factor in the eventual design. The current work describes a rotor dynamic analysis to assess the viability of such a system. A brief technology background, assumptions, analyses, and conclusions are discussed in this report. The results indicate that a foil bearing supported turbo alternator is possible, although more work will be needed to gain knowledge about foil bearing behavior in helium-xenon gas.

  9. The rationale/benefits of nuclear thermal rocket propulsion for NASA's lunar space transportation system

    Science.gov (United States)

    Borowski, Stanley K.

    1994-09-01

    The solid core nuclear thermal rocket (NTR) represents the next major evolutionary step in propulsion technology. With its attractive operating characteristics, which include high specific impulse (approximately 850-1000 s) and engine thrust-to-weight (approximately 4-20), the NTR can form the basis for an efficient lunar space transportation system (LTS) capable of supporting both piloted and cargo missions. Studies conducted at the NASA Lewis Research Center indicate that an NTR-based LTS could transport a fully-fueled, cargo-laden, lunar excursion vehicle to the Moon, and return it to low Earth orbit (LEO) after mission completion, for less initial mass in LEO than an aerobraked chemical system of the type studied by NASA during its '90-Day Study.' The all-propulsive NTR-powered LTS would also be 'fully reusable' and would have a 'return payload' mass fraction of approximately 23 percent--twice that of the 'partially reusable' aerobraked chemical system. Two NTR technology options are examined--one derived from the graphite-moderated reactor concept developed by NASA and the AEC under the Rover/NERVA (Nuclear Engine for Rocket Vehicle Application) programs, and a second concept, the Particle Bed Reactor (PBR). The paper also summarizes NASA's lunar outpost scenario, compares relative performance provided by different LTS concepts, and discusses important operational issues (e.g., reusability, engine 'end-of life' disposal, etc.) associated with using this important propulsion technology.

  10. Lightweight Damage Tolerant, High-Temperature Radiators for Nuclear Power and Propulsion

    Science.gov (United States)

    Craven, Paul D.; SanSoucie, Michael P.

    2015-01-01

    NASA is increasingly emphasizing exploration to bodies beyond near-Earth orbit. New propulsion systems and new spacecraft are being built for these missions. As the target bodies get further out from Earth, high energy density systems, e.g., nuclear fusion, for propulsion and power will be advantageous. The mass and size of these systems, including supporting systems such as the heat exchange system, including thermal radiators, will need to be as small as possible. Conventional heat exchange systems are a significant portion of the total thermal management mass and size. Nuclear electric propulsion (NEP) is a promising option for high-speed, in-space travel due to the high energy density of nuclear fission power sources and efficient electric thrusters. Heat from the reactor is converted to power for use in propulsion or for system power. The heat not used in the power conversion is then radiated to space as shown in figure 1. Advanced power conversion technologies will require high operating temperatures and would benefit from lightweight radiator materials. Radiator performance dictates power output for nuclear electric propulsion systems. Pitch-based carbon fiber materials have the potential to offer significant improvements in operating temperature, thermal conductivity, and mass. These properties combine to allow significant decreases in the total mass of the radiators and significant increases in the operating temperature of the fins. A Center-funded project at NASA Marshall Space Flight Center has shown that high thermal conductivity, woven carbon fiber fins with no matrix material, can be used to dissipate waste heat from NEP systems and because of high specific power (kW/kg), will require less mass and possibly less total area than standard metal and composite radiator fins for radiating the same amount of heat. This project uses an innovative approach to reduce the mass and size required for the thermal radiators to the point that in-space NEP and power

  11. A Crewed Mission to Apophis Using a Hybrid Bimodal Nuclear Thermal Electric Propulsion (BNTEP) System

    Science.gov (United States)

    Mccurdy, David R.; Borowski, Stanley K.; Burke, Laura M.; Packard, Thomas W.

    2014-01-01

    A BNTEP system is a dual propellant, hybrid propulsion concept that utilizes Bimodal Nuclear Thermal Rocket (BNTR) propulsion during high thrust operations, providing 10's of kilo-Newtons of thrust per engine at a high specific impulse (Isp) of 900 s, and an Electric Propulsion (EP) system during low thrust operations at even higher Isp of around 3000 s. Electrical power for the EP system is provided by the BNTR engines in combination with a Brayton Power Conversion (BPC) closed loop system, which can provide electrical power on the order of 100's of kWe. High thrust BNTR operation uses liquid hydrogen (LH2) as reactor coolant propellant expelled out a nozzle, while low thrust EP uses high pressure xenon expelled by an electric grid. By utilizing an optimized combination of low and high thrust propulsion, significant mass savings over a conventional NTR vehicle can be realized. Low thrust mission events, such as midcourse corrections (MCC), tank settling burns, some reaction control system (RCS) burns, and even a small portion at the end of the departure burn can be performed with EP. Crewed and robotic deep space missions to a near Earth asteroid (NEA) are best suited for this hybrid propulsion approach. For these mission scenarios, the Earth return V is typically small enough that EP alone is sufficient. A crewed mission to the NEA Apophis in the year 2028 with an expendable BNTEP transfer vehicle is presented. Assembly operations, launch element masses, and other key characteristics of the vehicle are described. A comparison with a conventional NTR vehicle performing the same mission is also provided. Finally, reusability of the BNTEP transfer vehicle is explored.

  12. The random signal generator of imitated nuclear radiation pulse

    International Nuclear Information System (INIS)

    Li Dongcang; Yang Lei; Yuan Shulin; Yang Yinghui; Zang Fujia

    2007-01-01

    Based in pseudo-random uniformity number, it produces random numbers of Gaussian distribution and exponential distribution by arithmetic. The hardware is the single-chip microcomputer of 89C51. Program language makes use of Keil C. The output pulse amplitude is Gaussian distribution, exponential distribution or uniformity distribution. Likewise, it has two mode or upwards two. The time alternation of output pulse is both periodic and exponential distribution. The generator has achieved output control of multi-mode distribution, imitated random characteristic of nuclear pulse in amplitude and in time. (authors)

  13. SOLID SOLUTION CARBIDES ARE THE KEY FUELS FOR FUTURE NUCLEAR THERMAL PROPULSION

    Science.gov (United States)

    Panda, Binayak; Hickman, Robert R.; Shah, Sandeep

    2005-01-01

    Nuclear thermal propulsion uses nuclear energy to directly heat a propellant (such as liquid hydrogen) to generate thrust for space transportation. In the 1960 s, the early Rover/Nuclear Engine for Rocket Propulsion Application (NERVA) program showed very encouraging test results for space nuclear propulsion but, in recent years, fuel research has been dismal. With NASA s renewed interest in long-term space exploration, fuel researchers are now revisiting the RoverMERVA findings, which indicated several problems with such fuels (such as erosion, chemical reaction of the fuel with propellant, fuel cracking, and cladding issues) that must be addressed. It is also well known that the higher the temperature reached by a propellant, the larger the thrust generated from the same weight of propellant. Better use of fuel and propellant requires development of fuels capable of reaching very high temperatures. Carbides have the highest melting points of any known material. Efforts are underway to develop carbide mixtures and solid solutions that contain uranium carbide, in order to achieve very high fuel temperatures. Binary solid solution carbides (U, Zr)C have proven to be very effective in this regard. Ternary carbides such as (U, Zr, X) carbides (where X represents Nb, Ta, W, and Hf) also hold great promise as fuel material, since the carbide mixtures in solid solution generate a very hard and tough compact material. This paper highlights past experience with early fuel materials and bi-carbides, technical problems associated with consolidation of the ingredients, and current techniques being developed to consolidate ternary carbides as fuel materials.

  14. Circuit processing pulsed signals from nuclear detector

    International Nuclear Information System (INIS)

    Kalfod Nielsen, H.

    1990-01-01

    A circuit for processing signals from a detector and occuring at random time intervals has a pulse-shaper, a delay and a processing circuit. The signal path is divided over part of its extent into parallel part-signal paths, each including an electronic switch and signal modifying circuits, a discriminator to detect a signal in the path and a control circuit for the switches and controlled by the discriminator being connected to the path ahead of the delay. The parallel paths are identical and the switch in each is ahead of the modifying circuits. When the discriminator detects a signal in the path the switch in on part path is made to conduct for at least as long as the duration of the signal as detected by the discriminator. The switches are preferable made to conduct cyclically. Processes increased number of signals, with quality of results not dependent on pulse rate and risk of errors substantially reduced. (au)

  15. Small Fast Spectrum Reactor Designs Suitable for Direct Nuclear Thermal Propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Bruce G. Schnitzler; Stanley K. Borowski

    2012-07-01

    Advancement of U.S. scientific, security, and economic interests through a robust space exploration program requires high performance propulsion systems to support a variety of robotic and crewed missions beyond low Earth orbit. Past studies, in particular those in support of both the Strategic Defense Initiative (SDI) and Space Exploration Initiative (SEI), have shown nuclear thermal propulsion systems provide superior performance for high mass high propulsive delta-V missions. The recent NASA Design Reference Architecture (DRA) 5.0 Study re-examined mission, payload, and transportation system requirements for a human Mars landing mission in the post-2030 timeframe. Nuclear thermal propulsion was again identified as the preferred in-space transportation system. A common nuclear thermal propulsion stage with three 25,000-lbf thrust engines was used for all primary mission maneuvers. Moderately lower thrust engines may also have important roles. In particular, lower thrust engine designs demonstrating the critical technologies that are directly extensible to other thrust levels are attractive from a ground testing perspective. An extensive nuclear thermal rocket technology development effort was conducted from 1955-1973 under the Rover/NERVA Program. Both graphite and refractory metal alloy fuel types were pursued. Reactors and engines employing graphite based fuels were designed, built and ground tested. A number of fast spectrum reactor and engine designs employing refractory metal alloy fuel types were proposed and designed, but none were built. The Small Nuclear Rocket Engine (SNRE) was the last engine design studied by the Los Alamos National Laboratory during the program. At the time, this engine was a state-of-the-art graphite based fuel design incorporating lessons learned from the very successful technology development program. The SNRE was a nominal 16,000-lbf thrust engine originally intended for unmanned applications with relatively short engine

  16. Small Fast Spectrum Reactor Designs Suitable for Direct Nuclear Thermal Propulsion

    Science.gov (United States)

    Schnitzler, Bruce G.; Borowski, Stanley K.

    2012-01-01

    Advancement of U.S. scientific, security, and economic interests through a robust space exploration program requires high performance propulsion systems to support a variety of robotic and crewed missions beyond low Earth orbit. Past studies, in particular those in support of the Space Exploration Initiative (SEI), have shown nuclear thermal propulsion systems provide superior performance for high mass high propulsive delta-V missions. The recent NASA Design Reference Architecture (DRA) 5.0 Study re-examined mission, payload, and transportation system requirements for a human Mars landing mission in the post-2030 timeframe. Nuclear thermal propulsion was again identified as the preferred in-space transportation system. A common nuclear thermal propulsion stage with three 25,000-lbf thrust engines was used for all primary mission maneuvers. Moderately lower thrust engines may also have important roles. In particular, lower thrust engine designs demonstrating the critical technologies that are directly extensible to other thrust levels are attractive from a ground testing perspective. An extensive nuclear thermal rocket technology development effort was conducted from 1955-1973 under the Rover/NERVA Program. Both graphite and refractory metal alloy fuel types were pursued. Reactors and engines employing graphite based fuels were designed, built and ground tested. A number of fast spectrum reactor and engine designs employing refractory metal alloy fuel types were proposed and designed, but none were built. The Small Nuclear Rocket Engine (SNRE) was the last engine design studied by the Los Alamos National Laboratory during the program. At the time, this engine was a state-of-the-art graphite based fuel design incorporating lessons learned from the very successful technology development program. The SNRE was a nominal 16,000-lbf thrust engine originally intended for unmanned applications with relatively short engine operations and the engine and stage design were

  17. A Review of Carbide Fuel Corrosion for Nuclear Thermal Propulsion Applications

    Science.gov (United States)

    Pelaccio, Dennis G.; El-Genk, Mohamed S.; Butt, Darryl P.

    1994-07-01

    At the operation conditions of interest in nuclear thermal propulsion reactors, carbide materials have been known to exhibit a number of life limiting phenomena. These include the formation of liquid, loss by vaporization, creep and corresponding gas flow restrictions, and local corrosion and fuel structure degradation due to excessive mechanical and/or thermal loading. In addition, the radiation environment in the reactor core can produce a substantial change in its local physical properties, which can produce high thermal stresses and corresponding stress fractures (cracking). Time-temperature history and cyclic operation of the nuclear reactor can also accelerate some of these processes. The University of New Mexico's Institute for Space Nuclear Power Studies, under NASA sponsorship has recently initiated a study to model the complicated hydrogen corrosion process. In support of this effort, an extensive review of the open literature was performed, and a technical expert workshop was conducted. This paper summarizes the results of this review.

  18. Fabrication and Testing of CERMET Fuel Materials for Nuclear Thermal Propulsion

    Science.gov (United States)

    Hickman, Robert; Broadway, Jeramie; Mireles, Omar

    2012-01-01

    A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on Nuclear Thermal Propulsion (NTP) is currently being developed for Advanced Space Exploration Systems. The overall goal of the project is to address critical NTP technology challenges and programmatic issues to establish confidence in the affordability and viability of NTP systems. The current technology roadmap for NTP identifies the development of a robust fuel form as a critical near term need. The lack of a qualified nuclear fuel is a significant technical risk that will require a considerable fraction of program resources to mitigate. Due to these risks and the cost for qualification, the development and selection of a primary fuel must begin prior to Authority to Proceed (ATP) for a specific mission. The fuel development is a progressive approach to incrementally reduce risk, converge the fuel materials, and mature the design and fabrication process of the fuel element. A key objective of the current project is to advance the maturity of CERMET fuels. The work includes fuel processing development and characterization, fuel specimen hot hydrogen screening, and prototypic fuel element testing. Early fuel materials development is critical to help validate requirements and fuel performance. The purpose of this paper is to provide an overview and status of the work at Marshall Space Flight Center (MSFC).

  19. A review of the status of, and prospects for, nuclear marine propulsion

    International Nuclear Information System (INIS)

    Edwards, J.

    1976-01-01

    It is stated that the matter of nuclear marine propulsion has been under consideration in the UK since 1957, at which time the Royal Navy commenced studies into the possibility of a nuclear powered 65,000 ton fleet support tanker. Nuclear warship studies started earlier in the USA, where studies were started in 1946 on the application of nuclear power to submarines and surface warships. The present position is that five nuclear merchant ships have been built, whereas 290 nuclear warships are either operational or building. Reference is made to a lecture given by the author in February 1974, in which the position at that time was reviewed, the present lecture up-dating that lecture with regard to subsequent events and their effects on the present prospects for nuclear merchant ships. Headings include the following: situation in early 1974; present situation; economic analyses; the energy situation; problems and prospects (economic assessments, inflation effects, safety requirements, construction time, refuelling requirements, ship residual value and decommissioning costs, training costs, insurance and indemnity, essential documentation, safety acceptance and port entry, licensing and legislative problems, accidents and their consequences); developments in marine reactor designs; and conclusions. The discussions are reproduced in full. (U.K.)

  20. Chemistry and propulsion; Chimie et propulsions

    Energy Technology Data Exchange (ETDEWEB)

    Potier, P. [Maison de la Chimie, 75 - Paris (France); Davenas, A. [societe Nationale des Poudres et des Explosifs - SNPE (France); Berman, M. [Air Force Office of Scientific Research, Arlington, VA (United States)] [and others

    2002-07-01

    During the colloquium on chemistry and propulsion, held in march 2002, ten papers have been presented. The proceedings are brought in this document: ramjet, scram-jet and Pulse Detonation Engine; researches and applications on energetic materials and propulsion; advances in poly-nitrogen chemistry; evolution of space propulsion; environmental and technological stakes of aeronautic propulsion; ramjet engines and pulse detonation engines, automobiles thermal engines for 2015, high temperature fuel cells for the propulsion domain, the hydrogen and the fuel cells in the future transports. (A.L.B.)

  1. High Power MPD Nuclear Electric Propulsion (NEP) for Artificial Gravity HOPE Missions to Callisto

    Science.gov (United States)

    McGuire, Melissa L.; Borowski, Stanley K.; Mason, Lee M.; Gilland, James

    2003-01-01

    This documents the results of a one-year multi-center NASA study on the prospect of sending humans to Jupiter's moon, Callisto, using an all Nuclear Electric Propulsion (NEP) space transportation system architecture with magnetoplasmadynamic (MPD) thrusters. The fission reactor system utilizes high temperature uranium dioxide (UO2) in tungsten (W) metal matrix cermet fuel and electricity is generated using advanced dynamic Brayton power conversion technology. The mission timeframe assumes on-going human Moon and Mars missions and existing space infrastructure to support launch of cargo and crewed spacecraft to Jupiter in 2041 and 2045, respectively.

  2. Nuclear propulsion systems for orbit transfer based on the particle bed reactor

    International Nuclear Information System (INIS)

    Powell, J.R.; Ludewig, H.; Horn, F.L.

    1987-01-01

    The technology of nuclear direct propulsion orbit transfer systems based on the Particle Bed Reactor (PBR) is described. A 200 megawatt illustrative design is presented for LEO to GEO and other high ΔV missions. The PBR-NOTV can be used in a one-way mode with the shuttle or an expendable launch vehicle, e.g., the Titan 34D7, or as a two-way reusable space tug. In the one-way mode, payload capacity is almost three times greater than that of chemical OTV's. PBR technology status is described and development needs outlined

  3. High power MPD Nuclear Electric Propulsion (NEP) for artificial gravity HOPE missions to Callisto

    International Nuclear Information System (INIS)

    McGuire, Melissa L.; Borowski, Stanley K.; Mason, Lee M.; Gilland, James

    2003-01-01

    The following paper documents the results of a one-year multi-center NASA study on the prospect of sending humans to Jupiter's moon, Callisto, using an all Nuclear Electric Propulsion (NEP) space transportation system architecture with magnetoplasmadynamic (MPD) thrusters. The fission reactor system utilizes high temperature uranium dioxide (UO2) in tungsten (W) metal matrix 'cermet' fuel and electricity is generated using advanced dynamic Brayton power conversion technology. The mission timeframe assumes on-going human Moon and Mars missions and existing space infrastructure to support launch of cargo and crewed spacecraft to Jupiter in 2041 and 2045, respectively

  4. Pulse sequence generator for nuclear magnetic resonance spectrometer

    International Nuclear Information System (INIS)

    Bartusek, K.

    1990-01-01

    The hardware and the properties are described of a pulsed sequence generator for a 200 MHz nuclear magnetic resonance spectrometer designed by the Institute for Research of Instrumentation of the Czechoslovak Academy of Sciences in Brno. The universal design of the generator meets the requirements of both NMR tomography and NMR microscopy. (author). 3 figs., 6 refs

  5. A remote maintenance robot system for a pulsed nuclear reactor

    International Nuclear Information System (INIS)

    Thunborg, S.

    1987-01-01

    This paper presents a remote maintenance robot system for use in a hazardous environment. The system consists of turntable, robot and hoist subsystems which operate under the control of a supervisory computer to perform coordinated programmed maintenance operations on a pulsed nuclear reactor. The system is operational

  6. Design of nuclear pulse shaped circuit based on proportional counter

    International Nuclear Information System (INIS)

    Song Qianqian; Cheng Yi; Tuo Xianguo

    2011-01-01

    Use the self-developed proportional to sample gas tritium in environment and make the measurement. For this detector, a kind of pulse shape circuit based on second order active low pass filtering circuit realized filtering and shaping nuclear pulse by high-speed operational amplifier, with less stages that has been approved for filter Gaussian wave. Use Multisim 10.0 to simulate the different parameters of the filter circuit. The simulation result was consistent with the theoretical results. The experiments proved the feasibility of this circuit, and at the same time provided a convenient and reliable method for analysis and optimization of the nuclear pulse waveform in order for discriminating by MCA. (authors)

  7. Space Nuclear Power and Propulsion - a basic Tool for the manned Exploration of the Solar System

    International Nuclear Information System (INIS)

    Frischauf, Norbert; Hamilton, Booz Allen

    2004-01-01

    Humanity has started to explore space more than 40 years ago. Numerous spacecraft have left the Earth in this endeavour, but while unmanned spacecraft were already sent out on missions, where they would eventually reach the outer limits of the Solar System, manned exploration has always been confined to the tiny bubble of the Earth's gravitational well, stretching out at maximum to our closest celestial companion - the Moon - during the era of the Apollo programme in the late 60's and early 70's. When mankind made its giant leap, the exploration of our cosmic neighbour was seen as the initial step for the manned exploration of the whole Solar System. Consequently ambitious research and development programmes were undertaken at that time to enable what seemed to be the next logical steps: the establishment of a permanent settled base on the Moon and the first manned mission to Mars in the 80's. Nuclear space power and propulsion played an important role in these entire future scenarios, hence ambitious development programmes were undertaken to make these technologies available. Unfortunately the 70's-paradigm shift in space policies did not only bring an end to the Apollo programme, but it also brought a complete halt to all of these technology programmes and confined the human presence in space to a tiny bubble including nothing more than the Earth's sphere and a mere shell of a few hundred kilometres of altitude, too small to even include the Moon. Today, after more than three decades, manned exploration of the Solar System has become an issue again and so are missions to Moon and Mars. However, studies and analyses show that all of these future plans are hampered by today's available propulsion systems and by the problematic of solar power generation at distances at and beyond of Mars, a problem, however, that can readily be solved by the utilisation of space nuclear reactors and propulsion systems. This paper intends to provide an overview on the various fission

  8. 'Bimodal' Nuclear Thermal Rocket (BNTR) propulsion for an artificial gravity HOPE mission to Callisto

    International Nuclear Information System (INIS)

    Borowski, Stanley K.; McGuire, Melissa L.; Mason, Lee M.; Gilland, James H.; Packard, Thomas W.

    2003-01-01

    This paper summarizes the results of a year long, multi-center NASA study which examined the viability of nuclear fission propulsion systems for Human Outer Planet Exploration (HOPE). The HOPE mission assumes a crew of six is sent to Callisto. Jupiter's outermost large moon, to establish a surface base and propellant production facility. The Asgard asteroid formation, a region potentially rich in water-ice, is selected as the landing site. High thrust BNTR propulsion is used to transport the crew from the Earth-Moon L1 staging node to Callisto then back to Earth in less than 5 years. Cargo and LH2 'return' propellant for the piloted Callisto transfer vehicle (PCTV) is pre-deployed at the moon (before the crew's departure) using low thrust, high power, nuclear electric propulsion (NEP) cargo and tanker vehicles powered by hydrogen magnetoplasmadynamic (MPD) thrusters. The PCTV is powered by three 25 klbf BNTR engines which also produce 50 kWe of power for crew life support and spacecraft operational needs. To counter the debilitating effects of long duration space flight (∼855 days out and ∼836 days back) under '0-gE' conditions, the PCTV generates an artificial gravity environment of '1-gE' via rotation of the vehicle about its center-of-mass at a rate of ∼4 rpm. After ∼123 days at Callisto, the 'refueled' PCTV leaves orbit for the trip home. Direct capsule re-entry of the crew at mission end is assumed. Dynamic Brayton power conversion and high temperature uranium dioxide (UO2) in tungsten metal ''cermet'' fuel is used in both the BNTR and NEP vehicles to maximize hardware commonality. Technology performance levels and vehicle characteristics are presented, and requirements for PCTV reusability are also discussed

  9. Effect of reactor coolant radioactivity upon configuration feasibility for a nuclear electric propulsion vehicle

    Science.gov (United States)

    Soffer, L.; Wright, G. N.

    1973-01-01

    A preliminary shielding analysis was carried out for a conceptual nuclear electric propulsion vehicle designed to transport payloads from low earth orbit to synchronous orbit. The vehicle employed a thermionic nuclear reactor operating at 1575 kilowatts and generated 120 kilowatts of electricity for a round-trip mission time of 2000 hours. Propulsion was via axially directed ion engines employing 3300 pounds of mercury as a propellant. The vehicle configuration permitted a reactor shadow shield geometry using LiH and the mercury propellant for shielding. However, much of the radioactive NaK reactor coolant was unshielded and in close proximity to the power conditioning electronics. An estimate of the radioactivity of the NaK coolant was made and its unshielded dose rate to the power conditioning equipment calculated. It was found that the activated NaK contributed about three-fourths of the gamma dose constraint. The NaK dose was considered a sufficiently high fraction of the allowable gamma dose to necessitate modifications in configuration.

  10. Pluto/Charon exploration utilizing a bi-modal PBR nuclear propulsion/power system

    Science.gov (United States)

    Venetoklis, Peter S.

    1995-01-01

    The paper describes a Pluto/Charon orbiter utilizing a bi-modal nuclear propulsion and power system based on the Particle Bed Reactor. The orbiter is sized for launch to Nuclear-Safe orbit atop a Titan IV or equivalent launch veicle. The bi-modal system provides thermal propulsion for Earth orbital departure and Pluto orbital capture, and 10 kWe of electric power for payload functions and for in-system maneuvering with ion thrusters. Ion thrusters are used to perform inclination changes about Pluto, a transfer from low Pluto orbit to low Charon orbit, and inclination changes about charon. A nominal payload can be deliverd in as little as 15 years, 1000 kg in 17 years, and close to 2000 kg in 20 years. Scientific return is enormously aided by the availability of up to 10 kWe, due to greater data transfer rates and more/better instruments. The bi-modal system can provide power at Pluto/Charon for 10 or more years, enabling an extremely robust, scientifically rewarding, and cost-effective exploration mission.

  11. Aircraft Nuclear Propulsion Program: Quarterly Progress Report for Period Ending December 31, 1956, Part 1 - 5

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, W. H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Cramer, S. J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Miller, A. J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    1957-03-12

    This quarterly progress report of the Aircraft Nuclear Propulsion Project at ORNL records the technical progress of the research on circulating-fuel reactors and other ANP research at the Laboratory under its Contract W-7405-eng-26. The report is divided into five major parts: 1. Aircraft Reactor Engineering, 2. Chemistry, 3. Metallurgy, 4. Heat Transfer and Physical Properties, Radiation Damage, and Fuel Recovery and Reprocessing, and 5. Reactor Shielding. The ANP Project is comprised of about 550 technical and scientific personnel engaged in many phases of research directed toward the achievement of nuclear propulsion of aircraft. A considerable portion of this research is performed in support of the work of other organizations participating in the national ANP effort. However, the bulk of the ANP research at ORNL is directed toward the development of a circulating-fuel type of reactor. The design, construction, and operation of the Aircraft Reactor Test (ART), with the cooperation of the Pratt & Whitney Aircraft Division, are the current objectives of the project. The ART is to be a power plant system that will include a 60-Mw circulating fuel reflector-moderator reactor and adequate means for heat disposal. Operation of the system will be for the purpose of determining feasibility and for studying the problems associated with the design, construction, and operation of a high-power circulating-fuel refIector-moderated aircraft reactor system.

  12. Mission needs and system commonality for space nuclear power and propulsion

    International Nuclear Information System (INIS)

    Buden, D.; Zuppero, A.; Redd, L.

    1993-01-01

    Nuclear power enables or significantly enhances a variety of space missions whether near-Earth, or for solar system exploration, lunar-Mars exploration and recovery of near-Earth resources. Performance optimizations for individual missions leads to a large number of power and propulsion systems to be developed. However, the realities of the budget and schedules indicates that the number of nuclear systems that will be developed are limited. One needs to seek the ''minimum requirements'' to do a job rather than the last ounce of performance, and areas of commonality. To develop a minimum number of systems to meet the overall DoD, NASA, and commercial needs, the broad spectrum of requirements has been examined along with cost drivers

  13. Discrimination of nuclear-explosion and lightning electromagnetic pulse

    International Nuclear Information System (INIS)

    Qi Shufeng; Li Ximei; Han Shaoqing; Niu Chao; Feng Jun; Liu Daizhi

    2012-01-01

    The discrimination of nuclear-explosion and lightning electromagnetic pulses was studied using empirical mode decomposition and the fractal analytical method. The box dimensions of nuclear-explosion and lightning electromagnetic pulses' original signals were calculated, and the box dimensions of the intrinsic mode functions (IMFs) of nuclear-explosion and lightning electromagnetic pulses' original signals after empirical mode decomposition were also obtained. The discrimination of nuclear explosion and lightning was studied using the nearest neighbor classification. The experimental results show that, the discrimination rate of the box dimension based on the first and second IMF after the original signal empirical mode decomposition is higher than that based on the third and forth IMF; the discrimination rate of the box dimension based on the original signal is higher than that based on any IMF; and the discrimination rate based on two-dimensional and three-dimensional characters is higher and more stable than that based on one-dimensional character, besides, the discrimination rate based on three-dimensional character is over 90%. (authors)

  14. Remote system for counting of nuclear pulses; Sistema remoto de conteo de pulsos nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Nieves V, J.A.; Garcia H, J.M.; Aguilar B, M.A. [Instituto Nacional de Investigaciones Nucleares, Ingenieria Electronica, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1999-07-01

    In this work, it is describe technically the remote system for counting of nuclear pulses, an integral system of the project radiological monitoring in a petroleum distillation tower. The system acquires the counting of incident nuclear particles in a nuclear detector which process this information and send it in serial form, using the RS-485 toward a remote receiver, which can be a Personal computer or any other device capable to interpret the communication protocol. (Author)

  15. Digital pulse processing: a new paradigm of nuclear instrumentation

    International Nuclear Information System (INIS)

    Ribas, Roberto V.

    2009-01-01

    Full text: High speed (100-200 MHz) and precise (12-14 bits) analog to digital converters are now available at relative low cost, the same occurring with devices known as FPGA - Field Programmable Gate Arrays. These facts made possible a large development of a new kind of data acquisition and pulse processing for nuclear physics experiments, where all after the pre-amp is digital. These new systems are already in production by the related industry, mainly for simple and specific applications, but are the very complex applications that gave a large impulse in the development of such systems. In low energy nuclear physics, for instance, new detecting systems now being planed, like the gamma-ray spectrometers GRETA in the US and AGATA in Europe, will have all pulse analysis and data acquisition based in this new technology. In these systems, the signal generated by the pre-amplifier coupled to the detector is the only analogically processed part of the acquisition system. A flash ADC samples the pre-amp pulse at a a rate of 100 millions per second, and with 12-14 bits of precision. Every pulse will then produce about 1-2K samples. All the pulse processing usually performed by analog devices, like spectroscopic amplifiers, fast amplifiers, constant fraction discriminators, etc. are now realized digitally, after the sampling of the pre-amp pulse. A large part of this processing is done in the FPGA devices, that can do it in a continuous flux at about 20-40 Mbytes per second. Several FPGA can work in parallel to process the large number of channels, normally necessary in these systems. We are now learning, testing and evaluating a simple system using this new technology, in order to develop a similar system to be used in our Laboratory. (author)

  16. Brayton Power Conversion System Study to Advance Technology Readiness for Nuclear Electric Propulsion

    Science.gov (United States)

    Allen, Bog; Delventhal, Rex; Frye, Patrick

    2004-01-01

    Recently, there has been significant interest within the aerospace community to develop space based nuclear power conversion technologies especially for exploring the outer planets of our solar system where the solar energy density is very low. To investigate these technologies NASA awarded several contracts under Project Prometheus, the Nuclear Systems Program. The studies described in this paper were performed under one of those contracts, which was to investigate the use of a nuclear power conversion system based on the closed Brayton cycle (CBC).The investigation performed included BPCS (Brayton Power Conversion System) trade studies to minimize system weight and radiator area and advance the state of the art of BPCS technology. The primary requirements for studies were a power level of 100 kWe (to the PPU), a low overall power system mass and a lifetime of 15 years (10 years full power). For the radiation environment, the system was to be capable of operation in the generic space environment and withstand the extreme environments surrounding Jupiter. The studies defined a BPCS design traceable to NEP (Nuclear Electric Propulsion) requirements and suitable for future missions with a sound technology plan for technology readiness level (TRL) advancement identified. The studies assumed a turbine inlet temperature approx. 100 C above the current the state of the art capabilities with materials issues and related development tasks identified. Analyses and evaluations of six different HRS (heat rejection system) designs and three primary power management and distribution (PMAD) configurations will be discussed in the paper.

  17. A review of the status of and prospects for nuclear marine propulsion

    International Nuclear Information System (INIS)

    Edwards, J.

    1976-01-01

    The review relates particularly to commercial nuclear merchant ships. The effects of the oil price escalation on world trade recession and price inflation are shown in relation to the rapid decrease in demand for new shipping and inflation in costs of any new construction. Economic analyses which began to be accepted as in favour of nuclear ships of relatively high power and high load factor have become somewhat less favourable, particularly from the point of view of higher investment costs and the presumed reluctance of shipowners to risk having these ships idle. On the other hand it is pointed out that the overall energy crisis remains and it is considered prudent to identify and seek solutions to those problems in nuclear ship propulsion which either still leave important uncertainties or which are likely to inhibit its use on a wide commercial scale. These are discussed under the following headings: economic assessments; safety acceptance and port entry; licensing and legislative problems; accidents and their consequences; decommissioning a nuclear ship; developments in the marine reactor designs. (U.K.)

  18. NMR magnetic field controller for pulsed nuclear magnetic resonance experiments

    International Nuclear Information System (INIS)

    Scheler, G.; Anacker, M.

    1975-01-01

    A nuclear magnetic resonance controller for magnetic fields, which can also be used for pulsed NMR investigations, is described. A longtime stability of 10 -7 is achieved. The control signal is generated by a modified time sharing circuit with resonance at the first side band of the 2 H signal. An exact calibration of the magnetic field is achieved by the variation of the H 1 - or of the time-sharing frequency. (author)

  19. Nuclear Thermal Rocket (Ntr) Propulsion: A Proven Game-Changing Technology for Future Human Exploration Missions

    Science.gov (United States)

    Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2012-01-01

    The NTR represents the next evolutionary step in high performance rocket propulsion. It generates high thrust and has a specific impulse (Isp) of approx.900 seconds (s) or more V twice that of today s best chemical rockets. The technology is also proven. During the previous Rover and NERVA (Nuclear Engine for Rocket Vehicle Applications) nuclear rocket programs, 20 rocket reactors were designed, built and ground tested. These tests demonstrated: (1) a wide range of thrust; (2) high temperature carbide-based nuclear fuel; (3) sustained engine operation; (4) accumulated lifetime; and (5) restart capability V all the requirements needed for a human mission to Mars. Ceramic metal cermet fuel was also pursued, as a backup option. The NTR also has significant growth and evolution potential. Configured as a bimodal system, it can generate electrical power for the spacecraft. Adding an oxygen afterburner nozzle introduces a variable thrust and Isp capability and allows bipropellant operation. In NASA s recent Mars Design Reference Architecture (DRA) 5.0 study, the NTR was selected as the preferred propulsion option because of its proven technology, higher performance, lower launch mass, simple assembly and mission operations. In contrast to other advanced propulsion options, NTP requires no large technology scale-ups. In fact, the smallest engine tested during the Rover program V the 25,000 lbf (25 klbf) Pewee engine is sufficient for human Mars missions when used in a clustered engine arrangement. The Copernicus crewed spacecraft design developed in DRA 5.0 has significant capability and a human exploration strategy is outlined here that uses Copernicus and its key components for precursor near Earth asteroid (NEA) and Mars orbital missions prior to a Mars landing mission. Initially, the basic Copernicus vehicle can enable reusable 1-year round trip human missions to candidate NEAs like 1991 JW and Apophis in the late 2020 s to check out vehicle systems. Afterwards, the

  20. Nuclear Thermal Propulsion (NTP): A Proven Growth Technology for Human NEO/Mars Exploration Missions

    Science.gov (United States)

    Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2012-01-01

    The nuclear thermal rocket (NTR) represents the next "evolutionary step" in high performance rocket propulsion. Unlike conventional chemical rockets that produce their energy through combustion, the NTR derives its energy from fission of Uranium-235 atoms contained within fuel elements that comprise the engine s reactor core. Using an "expander" cycle for turbopump drive power, hydrogen propellant is raised to a high pressure and pumped through coolant channels in the fuel elements where it is superheated then expanded out a supersonic nozzle to generate high thrust. By using hydrogen for both the reactor coolant and propellant, the NTR can achieve specific impulse (Isp) values of 900 seconds (s) or more - twice that of today s best chemical rockets. From 1955 - 1972, twenty rocket reactors were designed, built and ground tested in the Rover and NERVA (Nuclear Engine for Rocket Vehicle Applications) programs. These programs demonstrated: (1) high temperature carbide-based nuclear fuels; (2) a wide range of thrust levels; (3) sustained engine operation; (4) accumulated lifetime at full power; and (5) restart capability - all the requirements needed for a human Mars mission. Ceramic metal "cermet" fuel was pursued as well, as a backup option. The NTR also has significant "evolution and growth" capability. Configured as a "bimodal" system, it can generate its own electrical power to support spacecraft operational needs. Adding an oxygen "afterburner" nozzle introduces a variable thrust and Isp capability and allows bipropellant operation. In NASA s recent Mars Design Reference Architecture (DRA) 5.0 study, the NTR was selected as the preferred propulsion option because of its proven technology, higher performance, lower launch mass, versatile vehicle design, simple assembly, and growth potential. In contrast to other advanced propulsion options, no large technology scale-ups are required for NTP either. In fact, the smallest engine tested during the Rover program

  1. Mars mission opportunity and transit time sensitivity for a nuclear thermal rocket propulsion application

    International Nuclear Information System (INIS)

    Young, A.C.; Mulqueen, J.A.; Nishimuta, E.L.; Emrich, W.J.

    1993-01-01

    President George Bush's 1989 challenge to America to support the Space Exploration Initiative (SEI) of ''Back to the Moon and Human Mission to Mars'' gives the space industry an opportunity to develop effective and efficient space transportation systems. This paper presents stage performance and requirements for a nuclear thermal rocket (NTR) Mars transportation system to support the human Mars mission of the SEI. Two classes of Mars mission profiles are considered in developing the NTR propulsion vehicle performance and requirements. The two Mars mission classes include the opposition class and conjunction class. The opposition class mission is associated with relatively short Mars stay times ranging from 30 to 90 days and total mission duration of 350 to 600 days. The conjunction class mission is associated with much longer Mars stay times ranging from 500 to 600 days and total mission durations of 875 to 1,000 days. Vehicle mass scaling equations are used to determine the NTR stage mass, size, and performance range required for different Mars mission opportunities and for different Mars mission durations. Mission opportunities considered include launch years 2010 to 2018. The 2010 opportunity is the most demanding launch opportunity and the 2018 opportunity is the least demanding opportunity. NTR vehicle mass and size sensitivity to NTR engine thrust level, engine specific impulse, NTR engine thrust-to-weight ratio, and Mars surface payload are presented. NTR propulsion parameter ranges include those associated with NERVA, particle bed reactor (PBR), low-pressure, and ceramic-metal-type engine design

  2. Mars mission opportunity and transit time sensitivity for a nuclear thermal rocket propulsion application

    Science.gov (United States)

    Young, Archie C.; Mulqueen, John A.; Nishimuta, Ena L.; Emrich, William J.

    1993-01-01

    President George Bush's 1989 challenge to America to support the Space Exploration Initiative (SEI) of ``Back to the Moon and Human Mission to Mars'' gives the space industry an opportunity to develop effective and efficient space transportation systems. This paper presents stage performance and requirements for a nuclear thermal rocket (NTR) Mars transportation system to support the human Mars mission of the SEI. Two classes of Mars mission profiles are considered in developing the NTR propulsion vehicle performance and requirements. The two Mars mission classes include the opposition class and conjunction class. The opposition class mission is associated with relatively short Mars stay times ranging from 30 to 90 days and total mission duration of 350 to 600 days. The conjunction class mission is associated with much longer Mars stay times ranging from 500 to 600 days and total mission durations of 875 to 1,000 days. Vehicle mass scaling equations are used to determine the NTR stage mass, size, and performance range required for different Mars mission opportunities and for different Mars mission durations. Mission opportunities considered include launch years 2010 to 2018. The 2010 opportunity is the most demanding launch opportunity and the 2018 opportunity is the least demanding opportunity. NTR vehicle mass and size sensitivity to NTR engine thrust level, engine specific impulse, NTR engine thrust-to-weight ratio, and Mars surface payload are presented. NTR propulsion parameter ranges include those associated with NERVA, particle bed reactor (PBR), low-pressure, and ceramic-metal-type engine design.

  3. A novel digital pulse processing architecture for nuclear instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Moline, Yoann; Thevenin, Mathieu; Corre, Gwenole [CEA, LIST - Laboratoire Capteurs et Architectures electroniques, F-91191 Gif-sur-Yvette, (France); Paindavoine, Michel [CNRS, Universite de Bourgogne - Laboratoire d' Etude de l' Apprentissage et du Developpement, 21000 DIJON, (France)

    2015-07-01

    The field of nuclear instrumentation covers a wide range of applications, including counting, spectrometry, pulse shape discrimination and multi-channel coincidence. These applications are the topic of many researches, new algorithms and implementations are constantly proposed thanks to advances in digital signal processing. However, these improvements are not yet implemented in instrumentation devices. This is especially true for neutron-gamma discrimination applications which traditionally use charge comparison method while literature proposes other algorithms based on frequency domain or wavelet theory which show better performances. Another example is pileups which are generally rejected while pileup correction algorithms also exist. These processes are traditionally performed offline due to two issues. The first is the Poissonian characteristic of the signal, composed of random arrival pulses which requires to current architectures to work in data flow. The second is the real-time requirement, which implies losing pulses when the pulse rate is too high. Despite the possibility of treating the pulses independently from each other, current architectures paralyze the acquisition of the signal during the processing of a pulse. This loss is called dead-time. These two issues have led current architectures to use dedicated solutions based on re-configurable components like Field Programmable Gate Arrays (FPGAs) to overcome the need of performance necessary to deal with dead-time. However, dedicated hardware algorithm implementations on re-configurable technologies are complex and time-consuming. For all these reasons, a programmable Digital pulse Processing (DPP) architecture in a high level language such as Cor C++ which can reduce dead-time would be worthwhile for nuclear instrumentation. This would reduce prototyping and test duration by reducing the level of hardware expertise to implement new algorithms. However, today's programmable solutions do not meet

  4. A novel digital pulse processing architecture for nuclear instrumentation

    International Nuclear Information System (INIS)

    Moline, Yoann; Thevenin, Mathieu; Corre, Gwenole; Paindavoine, Michel

    2015-01-01

    The field of nuclear instrumentation covers a wide range of applications, including counting, spectrometry, pulse shape discrimination and multi-channel coincidence. These applications are the topic of many researches, new algorithms and implementations are constantly proposed thanks to advances in digital signal processing. However, these improvements are not yet implemented in instrumentation devices. This is especially true for neutron-gamma discrimination applications which traditionally use charge comparison method while literature proposes other algorithms based on frequency domain or wavelet theory which show better performances. Another example is pileups which are generally rejected while pileup correction algorithms also exist. These processes are traditionally performed offline due to two issues. The first is the Poissonian characteristic of the signal, composed of random arrival pulses which requires to current architectures to work in data flow. The second is the real-time requirement, which implies losing pulses when the pulse rate is too high. Despite the possibility of treating the pulses independently from each other, current architectures paralyze the acquisition of the signal during the processing of a pulse. This loss is called dead-time. These two issues have led current architectures to use dedicated solutions based on re-configurable components like Field Programmable Gate Arrays (FPGAs) to overcome the need of performance necessary to deal with dead-time. However, dedicated hardware algorithm implementations on re-configurable technologies are complex and time-consuming. For all these reasons, a programmable Digital pulse Processing (DPP) architecture in a high level language such as Cor C++ which can reduce dead-time would be worthwhile for nuclear instrumentation. This would reduce prototyping and test duration by reducing the level of hardware expertise to implement new algorithms. However, today's programmable solutions do not meet

  5. Kinetic—a system code for analyzing nuclear thermal propulsion rocket engine transients

    Science.gov (United States)

    Schmidt, Eldon; Lazareth, Otto; Ludewig, Hans

    1993-01-01

    A system code suitable for analyzing Nuclear Thermal Propulsion (NTP) rocket engines is described in this paper. The code consists of a point reactor model and nodes to describe the fluid dynamics and heat transfer mechanism. Feedback from the fuel, coolant, moderator and reflector are allowed for, and the control of the reactor is by motion of controls element (drums or rods). The worth of the control element and feedback coefficients are predetermined. Separate models for the turbo-pump assembly (TPA) and nozzle are also included. The model to be described in this paper is specific for the Particle Bed Reactor (PBR). An illustrative problem is solved. This problem consists of a PBR operating in a blowdown mode.

  6. KINETIC: A system code for analyzing Nuclear thermal propulsion rocket engine transients

    Science.gov (United States)

    Schmidt, E.; Lazareth, O.; Ludewig, H.

    1993-07-01

    A system code suitable for analyzing Nuclear Thermal Propulsion (NTP) rocket engines is described in this paper. The code consists of a point reactor model and nodes to describe the fluid dynamics and heat transfer mechanism. Feedback from the fuel coolant, moderator and reflector are allowed for, and the control of the reactor is by motion of control elements (drums or rods). The worth of the control clement and feedback coefficients are predetermined. Separate models for the turbo-pump assembly (TPA) and nozzle are also included. The model to be described in this paper is specific for the Particle Bed Reactor (PBR). An illustrative problem is solved. This problem consists of a PBR operating in a blowdown mode.

  7. Application of a bi-modal PBR nuclear propulsion and power system to military missions

    Science.gov (United States)

    Venetoklis, Peter S.

    1995-01-01

    The rapid proliferation of arms technology and space access combined with current economic realities in the United States are creating ever greater demands for more capable space-based military assets. The paper illustrates that bi-modal nuclear propulsion and power based on the Particle Bed Reactor (PBR) is a high-leverage tehcnology that can maximize utility while minimizing cost. Mission benefits offered by the bi-modal PBR, including enhanced maneuverability, lifetime, survivability, payload power, and operational flexibility, are discussed. The ability to deliver desired payloads on smaller boosters is also illustrated. System descriptions and parameters for 10 kWe and 100 kWe power output levels are summarized. It is demonstrated via design exercise that bi-modal PBR dramtically enhances performance of a military satellite in geosynchronous orbit, increasing payload mass, payload power, and maneuverability.

  8. MCNP benchmark analyses of critical experiments for the Space Nuclear Thermal Propulsion program

    Science.gov (United States)

    Selcow, Elizabeth C.; Cerbone, Ralph J.; Ludewig, Hans; Mughabghab, Said F.; Schmidt, Eldon; Todosow, Michael; Parma, Edward J.; Ball, Russell M.; Hoovler, Gary S.

    1993-01-01

    Benchmark analyses have been performed of Particle Bed Reactor (PBR) critical experiments (CX) using the MCNP radiation transport code. The experiments have been conducted at the Sandia National Laboratory reactor facility in support of the Space Nuclear Thermal Propulsion (SNTP) program. The test reactor is a nineteen element water moderated and reflected thermal system. A series of integral experiments have been carried out to test the capabilities of the radiation transport codes to predict the performance of PBR systems. MCNP was selected as the preferred radiation analysis tool for the benchmark experiments. Comparison between experimental and calculational results indicate close agreement. This paper describes the analyses of benchmark experiments designed to quantify the accuracy of the MCNP radiation transport code for predicting the performance characteristics of PBR reactors.

  9. MCNP benchmark analyses of critical experiments for the Space Nuclear Thermal Propulsion program

    International Nuclear Information System (INIS)

    Selcow, E.C.; Cerbone, R.J.; Ludewig, H.; Mughabghab, S.F.; Schmidt, E.; Todosow, M.; Parma, E.J.; Ball, R.M.; Hoovler, G.S.

    1993-01-01

    Benchmark analyses have been performed of Particle Bed Reactor (PBR) critical experiments (CX) using the MCNP radiation transport code. The experiments have been conducted at the Sandia National Laboratory reactor facility in support of the Space Nuclear Thermal Propulsion (SNTP) program. The test reactor is a nineteen element water moderated and reflected thermal system. A series of integral experiments have been carried out to test the capabilities of the radiation transport codes to predict the performance of PBR systems. MCNP was selected as the preferred radiation analysis tool for the benchmark experiments. Comparison between experimental and calculational results indicate close agreement. This paper describes the analyses of benchmark experiments designed to quantify the accuracy of the MCNP radiation transport code for predicting the performance characteristics of PBR reactors

  10. The ERDA thermionic program. [for nuclear propulsion and utility power plants

    Science.gov (United States)

    Newby, G. A.

    1975-01-01

    A rationale for increased Federal support of thermionic research is considered and the objectives and milestones of the thermionic program of the U.S. Energy Research and Development Administration (ERDA) are examined. The ERDA program is to provide very high specific power systems needed for planned future NASA nuclear electric propulsion missions. Another objective is the enhancement of the overall thermal conversion efficiency of the present utility power plants from approximately 35% to 50% or more. Attention is given to key problem areas, taking into account inadequate analytical tools, the reduction of the plasma arc-drop losses, aspects of hot shell materials development, and the coordination of the participating groups programmatic activities.

  11. An assessment of testing requirement impacts on nuclear thermal propulsion ground test facility design

    International Nuclear Information System (INIS)

    Shipers, L.R.; Ottinger, C.A.; Sanchez, L.C.

    1993-01-01

    Programs to develop solid core nuclear thermal propulsion (NTP) systems have been under way at the Department of Defense (DoD), the National Aeronautics and Space Administration (NASA), and the Department of Energy (DOE). These programs have recognized the need for a new ground test facility to support development of NTP systems. However, the different military and civilian applications have led to different ground test facility requirements. The Department of Energy (DOE) in its role as landlord and operator of the proposed research reactor test facilities has initiated an effort to explore opportunities for a common ground test facility to meet both DoD and NASA needs. The baseline design and operating limits of the proposed DoD NTP ground test facility are described. The NASA ground test facility requirements are reviewed and their potential impact on the DoD facility baseline is discussed

  12. Final Environmental Impact Statement (EIS) for the Space Nuclear Thermal Propulsion (SNTP) program

    Science.gov (United States)

    1991-09-01

    A program has been proposed to develop the technology and demonstrate the feasibility of a high-temperature particle bed reactor (PBR) propulsion system to be used to power an advanced second stage nuclear rocket engine. The purpose of this Final Environmental Impact Statement (FEIS) is to assess the potential environmental impacts of component development and testing, construction of ground test facilities, and ground testing. Major issues and goals of the program include the achievement and control of predicted nuclear power levels; the development of materials that can withstand the extremely high operating temperatures and hydrogen flow environments; and the reliable control of cryogenic hydrogen and hot gaseous hydrogen propellant. The testing process is designed to minimize radiation exposure to the environment. Environmental impact and mitigation planning are included for the following areas of concern: (1) Population and economy; (2) Land use and infrastructure; (3) Noise; (4) Cultural resources; (5) Safety (non-nuclear); (6) Waste; (7) Topography; (8) Geology; (9) Seismic activity; (10) Water resources; (11) Meteorology/Air quality; (12) Biological resources; (13) Radiological normal operations; (14) Radiological accidents; (15) Soils; and (16) Wildlife habitats.

  13. Technology Implementation Plan: Irradiation Testing and Qualification for Nuclear Thermal Propulsion Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Thomas J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howard, Richard H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rader, Jordan D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-09-01

    This document is a notional technology implementation plan (TIP) for the development, testing, and qualification of a prototypic fuel element to support design and construction of a nuclear thermal propulsion (NTP) engine, specifically its pre-flight ground test. This TIP outlines a generic methodology for the progression from non-nuclear out-of-pile (OOP) testing through nuclear in-pile (IP) testing, at operational temperatures, flows, and specific powers, of an NTP fuel element in an existing test reactor. Subsequent post-irradiation examination (PIE) will occur in existing radiological facilities. Further, the methodology is intended to be nonspecific with respect to fuel types and irradiation or examination facilities. The goals of OOP and IP testing are to provide confidence in the operational performance of fuel system concepts and provide data to program leadership for system optimization and fuel down-selection. The test methodology, parameters, collected data, and analytical results from OOP, IP, and PIE will be documented for reference by the NTP operator and the appropriate regulatory and oversight authorities. Final full-scale integrated testing would be performed separately by the reactor operator as part of the preflight ground test.

  14. The role of nuclear power and nuclear propulsion in the peaceful exploration of space

    International Nuclear Information System (INIS)

    2005-09-01

    This publication has been produced within the framework of the IAEA's innovative reactor and fuel cycle technology development activities. It elucidates the role that peaceful space related nuclear power research and development could play in terrestrial innovative reactor and fuel cycle technology development initiatives. This review is a contribution to the Inter-Agency Meeting on Outer Space Activities, and reflects the stepped up efforts of the Scientific and Technical Subcommittee of the Committee on the Peaceful Uses of Outer Space to further strengthen cooperation between international organizations in space related activities. Apart from fostering information exchange within the United Nations organizations, this publication aims at finding new potential fields for innovative reactor and fuel cycle technology development. In assessing the status and reviewing the role of nuclear power in the peaceful exploration of space, it also aims to initiate a discussion on the potential benefits of space related nuclear power technology research and development to the development of innovative terrestrial nuclear systems

  15. An examination of bimodal nuclear power and propulsion benefits for outer solar system missions

    International Nuclear Information System (INIS)

    Zubrin, R.; Mondt, J.

    1996-01-01

    This paper presents the results of an analysis of the capability of nuclear bimodal systems to perform outer solar system exploration missions. Missions of interest include orbiter missions to Jupiter, Saturn, Uranus, Neptune, and Pluto. An initial technology baseline consisting of the NEBA 10 kWe, 1000 N thrust, 850 s, 1500 kg bimodal system was selected, and its performance examined against a data base for trajectories to outer solar system planetary destinations to select optimal direct and gravity assisted trajectories for study. A conceptual design for a common bimodal spacecraft capable of performing missions to all the planetary destinations was developed and made the basis of end to end mission designs for orbiter missions to Jupiter, Saturn, and Neptune. All mission designs considered use the Atlas 2AS for launch. The radiological hazard associated with using Earth gravity assists on such missions was examined and shown to be small compared to that currently accepted on Earth fly-by missions involving RTGs. It is shown that the bimodal nuclear power and propulsion system offers many attractive options for planetary missions, including both conventional planetary missions in which all instruments are carried by a single primary orbiting spacecraft, and unconventional missions in which the primary spacecraft acts as a carrier, relay, and mother ship for a fleet of micro spacecraft deployed at the planetary destination. copyright 1996 American Institute of Physics

  16. Solid-State Thermionic Nuclear Power for Megawatt Propulsion, Planetary Surface and Commercial Power Project

    Science.gov (United States)

    George, Jeffrey

    2014-01-01

    Thermionic (TI) power conversion is a promising technology first investigated for power conversion in the 1960's, and of renewed interest due to modern advances in nanotechnology, MEMS, materials and manufacturing. Benefits include high conversion efficiency (20%), static operation with no moving parts and potential for high reliability, greatly reduced plant complexity, and the potential for reduced development costs. Thermionic emission, credited to Edison in 1880, forms the basis of vacuum tubes and much of 20th century electronics. Heat can be converted into electricity when electrons emitted from a hot surface are collected across a small gap. For example, two "small" (6 kWe) Thermionic Space Reactors were flown by the USSR in 1987-88 for ocean radar reconnaissance. Higher powered Nuclear-Thermionic power systems driving Electric Propulsion (Q-thruster, VASIMR, etc.) may offer the breakthrough necessary for human Mars missions of Power generation on Earth could benefit from simpler, moe economical nuclear plants, and "topping" of more fuel and emission efficient fossil-fuel plants.

  17. Electromagnetic coupling of high-altitude, nuclear electromagnetic pulses

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    We have used scale models to measure the predicted coupling of electromagnetic fields simulating the effects of high-altitude nuclear electromagnetic pulses (HEMP) on the interior surfaces of electronic components. Predictive tools for exterior coupling are adequate. For interior coupling, however, such tools are in their infancy. Our methodological approach combines analytical, computational, and laboratory techniques in a complementary way to take advantage of their separate strengths. Computer models are a promising tool, as they can be used to treat complex objects with arbitrary shapes, dielectrics, and cables, and multiple apertures. Laboratory tests can expand the domain of investigation even further

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

    Science.gov (United States)

    Palaszewski, Bryan

    2016-01-01

    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.

  19. Summary of particle bed reactor designs for the Space Nuclear Thermal Propulsion Program

    Science.gov (United States)

    Powell, J. R.; Ludewig, H.; Todosow, M.

    1993-09-01

    A summary report of the Particle Bed Reactor (PBR) designs considered for the space nuclear thermal propulsion program has been prepared. The first chapters outline the methods of analysis, and their validation. Monte Carlo methods are used for the physics analysis, several new algorithms are used for the fluid dynamics heat transfer and engine system analysis, and commercially available codes are used for the stress analysis. A critical experiment, prototypic of the PBR was used for the physics validation, and blowdown experiments using fuel beds of prototypic dimensions were used to validate the power extraction capabilities from particle beds. In all four different PBR rocket reactor designs were studied to varying degrees of detail. They varied in power from 400 MW to 2000 MW. These designs were all characterized by a negative prompt coefficient, due to Doppler feedback, and the feedback due to moderator heat up varied from slightly negative to slightly positive. In all practical cases, the coolant worth was positive, although core configurations with negative coolant worth could be designed. In all practical cases the thrust/weight ratio was greater than 20.

  20. An overview of the Nuclear Electric Propulsion Space Test Program (NEPSTP) satellite

    International Nuclear Information System (INIS)

    Voss, S.S.; Reynolds, E.L.

    1994-01-01

    Early in 1992 the idea of purchasing a Russian designed and fabricated space reactor power system and integrating it with a US designed satellite went from fiction to reality with the purchase of the first two Topaz II reactors by the Strategic Defense Initiative Organization (now the Ballistic Missile Defense Organization (BMDO)). The New Mexico Alliance was formed to establish a ground test facility in which to perform nonnuclear systems testing of the Topaz II, and to evaluate the Topaz II system for flight testing with respect to safety, performance, and operability. In conjunction, SDIO requested that the Applied Physics Laboratory in Laurel, MD propose a mission and design a satellite in which the Topaz II could be used as the power source. The outcome of these two activities was the design of the Nuclear Electric Propulsion Space Test Program (NEPSTP) satellite which combines a modified Russian Topaz II power system with a US designed satellite to achieve a specified mission. Due to funding reduction within the SDIO, the Topaz II flight program was postponed indefinitely at the end of Fiscal year 1993. The purpose of this paper is to present an overview of the NEPSTP mission and the satellite design at the time the flight program ended

  1. Brayton Power Conversion System Parametric Design Modelling for Nuclear Electric Propulsion

    Science.gov (United States)

    Ashe, Thomas L.; Otting, William D.

    1993-01-01

    The parametrically based closed Brayton cycle (CBC) computer design model was developed for inclusion into the NASA LeRC overall Nuclear Electric Propulsion (NEP) end-to-end systems model. The code is intended to provide greater depth to the NEP system modeling which is required to more accurately predict the impact of specific technology on system performance. The CBC model is parametrically based to allow for conducting detailed optimization studies and to provide for easy integration into an overall optimizer driver routine. The power conversion model includes the modeling of the turbines, alternators, compressors, ducting, and heat exchangers (hot-side heat exchanger and recuperator). The code predicts performance to significant detail. The system characteristics determined include estimates of mass, efficiency, and the characteristic dimensions of the major power conversion system components. These characteristics are parametrically modeled as a function of input parameters such as the aerodynamic configuration (axial or radial), turbine inlet temperature, cycle temperature ratio, power level, lifetime, materials, and redundancy.

  2. Brayton power conversion system parametric design modelling for nuclear electric propulsion. Final report

    International Nuclear Information System (INIS)

    Ashe, T.L.; Otting, W.D.

    1993-11-01

    The parametrically based closed Brayton cycle (CBC) computer design model was developed for inclusion into the NASA LeRC overall Nuclear Electric Propulsion (NEP) end-to-end systems model. The code is intended to provide greater depth to the NEP system modeling which is required to more accurately predict the impact of specific technology on system performance. The CBC model is parametrically based to allow for conducting detailed optimization studies and to provide for easy integration into an overall optimizer driver routine. The power conversion model includes the modeling of the turbines, alternators, compressors, ducting, and heat exchangers (hot-side heat exchanger and recuperator). The code predicts performance to significant detail. The system characteristics determined include estimates of mass, efficiency, and the characteristic dimensions of the major power conversion system components. These characteristics are parametrically modeled as a function of input parameters such as the aerodynamic configuration (axial or radial), turbine inlet temperature, cycle temperature ratio, power level, lifetime, materials, and redundancy

  3. A One-year, Short-Stay Crewed Mars Mission Using Bimodal Nuclear Thermal Electric Propulsion (BNTEP) - A Preliminary Assessment

    Science.gov (United States)

    Burke, Laura A.; Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2013-01-01

    A crewed mission to Mars poses a signi cant challenge in dealing with the physiolog- ical issues that arise with the crew being exposed to a near zero-gravity environment as well as signi cant solar and galactic radiation for such a long duration. While long sur- face stay missions exceeding 500 days are the ultimate goal for human Mars exploration, short round trip, short surface stay missions could be an important intermediate step that would allow NASA to demonstrate technology as well as study the physiological e ects on the crew. However, for a 1-year round trip mission, the outbound and inbound hy- perbolic velocity at Earth and Mars can be very large resulting in a signi cant propellant requirement for a high thrust system like Nuclear Thermal Propulsion (NTP). Similarly, a low thrust Nuclear Electric Propulsion (NEP) system requires high electrical power lev- els (10 megawatts electric (MWe) or more), plus advanced power conversion technology to achieve the lower speci c mass values needed for such a mission. A Bimodal Nuclear Thermal Electric Propulsion (BNTEP) system is examined here that uses three high thrust Bimodal Nuclear Thermal Rocket (BNTR) engines allowing short departure and capture maneuvers. The engines also generate electrical power that drives a low thrust Electric Propulsion (EP) system used for ecient interplanetary transit. This combined system can help reduce the total launch mass, system and operational requirements that would otherwise be required for equivalent NEP or Solar Electric Propulsion (SEP) mission. The BNTEP system is a hybrid propulsion concept where the BNTR reactors operate in two separate modes. During high-thrust mode operation, each BNTR provides 10's of kilo- Newtons of thrust at reasonably high speci c impulse (Isp) of 900 seconds for impulsive trans-planetary injection and orbital insertion maneuvers. When in power generation / EP mode, the BNTR reactors are coupled to a Brayton power conversion system allowing each

  4. Prospects for Nuclear Electric Propulsion Using Closed-Cycle Magnetohydrodynamic Energy Conversion

    Science.gov (United States)

    Litchford, R. J.; Bitteker, L. J.; Jones, J. E.

    2001-01-01

    Nuclear electric propulsion (NEP) has long been recognized as a major enabling technology for scientific and human exploration of the solar system, and it may conceivably form the basis of a cost-effective space transportation system suitable for space commerce. The chief technical obstacles to realizing this vision are the development of efficient, high-power (megawatt-class) electric thrusters and the development of low specific mass (less than 1 kg/kWe) power plants. Furthermore, comprehensive system analyses of multimegawatt class NEP systems are needed in order to critically assess mission capability and cost attributes. This Technical Publication addresses some of these concerns through a systematic examination of multimegawatt space power installations in which a gas-cooled nuclear reactor is used to drive a magnetohydrodynamic (MHD) generator in a closed-loop Brayton cycle. The primary motivation for considering MHD energy conversion is the ability to transfer energy out of a gas that is simply too hot for contact with any solid material. This has several intrinsic advantages including the ability to achieve high thermal efficiency and power density and the ability to reject heat at elevated temperatures. These attributes lead to a reduction in system specific mass below that obtainable with turbine-based systems, which have definite solid temperature limits for reliable operation. Here, the results of a thermodynamic cycle analysis are placed in context with a preliminary system analysis in order to converge on a design space that optimizes performance while remaining clearly within established bounds of engineering feasibility. MHD technology issues are discussed including the conceptual design of a nonequilibrium disk generator and opportunities for exploiting neutron-induced ionization mechanisms as a means of increasing electrical conductivity and enhancing performance and reliability. The results are then used to make a cursory examination of piloted

  5. Model of a Nuclear Security Naval Agency for radiation control of the Industrial Complex of of Submarine Construction and Maintenance Ship with Nuclear Propulsion

    International Nuclear Information System (INIS)

    Lins Junior, Amilton de Sousa

    2017-01-01

    Due to the construction, by Brazilian Navy, of a Submarine Construction and Maintenance Ship with Nuclear Propulsion, where, among other activities, the commissioning and exchange of the fuel elements of the reactor in the future Nuclear Submarine, and of a Naval Base where the Nuclear Submarine and the Conventional Submarines, it is necessary the establishment of a Nuclear Security Naval Agency to monitor activities involving ionizing radiation sources and nuclear materials aimed at the radiological protection of exposed occupationally individuals (IOE), the general public and the environment. It should be noted that nuclear and radioactive material will be present only in a part of the yard called Radiological Complex. Therefore, the development of a structure for the control of the Radiological Complex is fundamental, considering that the future licensing process will be unprecedented in Brazil and will face several difficulties. This work presents a model of a structure for the radiological control of the industrial complex for the construction and maintenance of the submarine with nuclear propulsion, as well as the fundamental concepts of the activities, such as inspection, regulations and authorizations, to be carried out by the various component sectors of the Nuclear Security Naval Agency. (author)

  6. Comprehensive Technical Report, General Electric Direct-Air-Cycle Aircraft Nuclear Propulsion Program, Program Summary and References

    Energy Technology Data Exchange (ETDEWEB)

    Thornton, G.; Rothstein, A.J.

    1962-06-28

    This is one of twenty-one volumes sumarizing the Aircraft Nuclear Propulsion Program of the General Electric Company. This volume discusses the background to the General Electric program, and summarizes the various direct-air-cycle nuclear test assemblies and power plants that were developed. Because of the requirements of high performance, low weight, and small size, vast improvements in existing technology were required to meet the flight objectives. The technological progress achieved during the program is also summarized. The last appendix contains a compilation of the abstracts, tables of contents, and reference lists of the other twenty volumes.

  7. The response of antennas on a submarine to nuclear electromagnetic pulse

    International Nuclear Information System (INIS)

    Gao Zheng; Li Junli; Fan Jiajin

    2005-01-01

    Nuclear electromagnetic pulse will do harm to the communication and navigation systems. In this paper, the response of antennas on a submarine to nuclear electromagnetic pulse is analyzed, and the induced current in antennas and energy collected by antennas are calculated, which are very important to the protection systems design. (authors)

  8. Direct Energy Conversion for Nuclear Propulsion at Low Specific Mass Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Low specific mass (< 3  kg/kW) in-space electric power and propulsion can drastically alter the paradigm for exploration of the Solar System, changing human...

  9. The Fusion Driven Rocket: Nuclear Propulsion through Direct Conversion of Fusion Energy

    Data.gov (United States)

    National Aeronautics and Space Administration — The Fusion Driven rocket (FDR) represents a revolutionary approach to fusion propulsion where the power source releases its energy directly into the propellant, not...

  10. Propulsion reactors

    International Nuclear Information System (INIS)

    Anon.

    1999-01-01

    A nuclear reactor equips the recently constructed French aircraft- carrier Charles-De-Gaulle, in a few months the second nuclear submarine (SNLE) of new generation will be operational. In last october the government launched the program Barracuda which consists of 6 submarines (SNA) whose series head will be operational in 2010. The main asset of nuclear propulsion is to allow an almost unlimited autonomy: soft water, air are produced inside the submarine and the maximum time spent underwater is only limited by human capacity to cope with confinement. CEA has 3 missions concerning country defence. First the designing, the fabrication and the maintenance of weapons, secondly the supplying of fissile materials and thirdly the nuclear propulsion. A new generation of propulsion reactors is being studied and a ground installation involving a test reactor equivalent to that on board is being built. This test reactor (RES) will simulate any type of on-board reactors by adjusting temperature, pressure, flowrate and even equipment such as steam generator. This reactor will validate the technological choices for the Barracuda program. (A.C.)

  11. Pulse monitor for upper extremities dosimetry in nuclear medicine

    International Nuclear Information System (INIS)

    Cledison de Jesus, Cunha; Divanizia do Nascimento, Souza

    2006-01-01

    In the manipulation of radioactive materials in Nuclear Medicine service the body parts of workers that are more displayed to the ionizing radiation are hands, underarm and arm. Therefore is necessary to developing personal dosimeters to monitoring of easy reproduction and low cost with purpose to determine the doses level radiation received by the worker in these extremities. However thermoluminescent dosimeters do not provide an instantaneous exposure reading, they are suitable for personal dosimetry because of their following advantages: wide useful dose range, small physical size and no need for high voltage or cables, i.e. stand alone character. The aim of this work is to investigation of a new pulse monitor, that has been developing with thermoluminescent detectors of CaSO 4 :Dy (TLD) using a small plate of acrylic, perforated cardboard to deposit the TLD. This set was involved in plastic to protect from humidity and other harmful ambient factors; moreover, a bracelet was inserted, adaptable for any worker. During the preparation of the personal dosimeters to monitor exposure it was necessary to verify their effectiveness to use by workers in a nuclear medicine service. The monitors have been submitted to procedures of performance evaluations by several tests: badges homogeneity, reproducibility, linearity, low detection limit, auto-irradiation, dosimeters stability, verification of the residual T.L. signal, visible light effect on dosimeters, energetic and angular dependence and TLD answer by influence of a simulator during radiation. Was possible to verify the efficiency of such upper extremities dosimeters and were obtained satisfactory results within of the limits demanded in the described tests above to this type of personal dosimeters. (authors)

  12. The design of nuclear magnetic resonance programmable pulsed source based SOPC

    International Nuclear Information System (INIS)

    Zhang Qingshun; Zhang Yakun; Wang Wenli

    2012-01-01

    The design of pulse source in the equipment of pulsed Nuclear Magnetic Resonance is studied based on SOPC. The strong processing power of Nios Ⅱ embedded processor and the design flexibility of FPGA are fully used. The SOPC system is built. The overall design plan for the pulse source is described. The design of programmable multi-pulse generation logic user-defined components in the FPGA is introduced mainly. Part of the implementation program and the task logic simulation waveforms are presented. The pulse source has better application value because a clear, stable and good quality multi-pulse output waveform can be shown on the oscilloscope finally. The system software and hardware are easy to be modified and upgraded, meeting different application of pulsed NMR pulse sequence in variety of requirements. (authors)

  13. Fusion Propulsion Z-Pinch Engine Concept

    Science.gov (United States)

    Miernik, J.; Statham, G.; Fabisinski, L.; Maples, C. D.; Adams, R.; Polsgrove, T.; Fincher, S.; Cassibry, J.; Cortez, R.; Turner, M.; hide

    2011-01-01

    Fusion-based nuclear propulsion has the potential to enable fast interplanetary transportation. Due to the great distances between the planets of our solar system and the harmful radiation environment of interplanetary space, high specific impulse (Isp) propulsion in vehicles with high payload mass fractions must be developed to provide practical and safe vehicles for human spaceflight missions. The Z-Pinch dense plasma focus method is a Magneto-Inertial Fusion (MIF) approach that may potentially lead to a small, low cost fusion reactor/engine assembly1. Recent advancements in experimental and theoretical understanding of this concept suggest favorable scaling of fusion power output yield 2. The magnetic field resulting from the large current compresses the plasma to fusion conditions, and this process can be pulsed over short timescales (10(exp -6 sec). This type of plasma formation is widely used in the field of Nuclear Weapons Effects testing in the defense industry, as well as in fusion energy research. A Decade Module 2 (DM2), approx.500 KJ pulsed-power is coming to the RSA Aerophysics Lab managed by UAHuntsville in January, 2012. A Z-Pinch propulsion concept was designed for a vehicle based on a previous fusion vehicle study called "Human Outer Planet Exploration" (HOPE), which used Magnetized Target Fusion (MTF) 3 propulsion. The reference mission is the transport of crew and cargo to Mars and back, with a reusable vehicle.

  14. University of Illinois nuclear pumped laser program. [experiments with a TRIGA pulsed reactor with a broad pulse and a low peak flux

    Science.gov (United States)

    Miley, G. H.

    1979-01-01

    The development of nuclear pumped lasers with improved efficiency, energy storage capability, and UF6 volume pumping is reviewed. Results of nuclear pumped laser experiments using a TRIGA-type pulsed reactor are outlined.

  15. Interaction of electromagnetic pulse with commercial nuclear-power-plant systems

    International Nuclear Information System (INIS)

    Ericson, D.M. Jr.; Strawe, D.F.; Sandberg, S.J.; Jones, V.K.; Rensner, G.D.; Shoup, R.W.; Hanson, R.J.; Williams, C.B.

    1983-02-01

    This study examines the interaction of the electromagnetic pulse from a high altitude nuclear burst with commercial nuclear power plant systems. The potential vulnerability of systems required for safe shutdown of a specific nuclear power plant are explored. EMP signal coupling, induced plant response and component damage thresholds are established using techniques developed over several decades under Defense Nuclear Agency sponsorship. A limited test program was conducted to verify the coupling analysis technique as applied to a nuclear power plant. The results are extended, insofar as possible, to other nuclear plants

  16. An FPGA-based nuclear pulse generator with a prescribed amplitude distribution

    Science.gov (United States)

    Ponikvar, Dušan

    2018-01-01

    A design of a low-cost electrical pulse generator capable of producing random pulses with exponentially decaying tail as coming from a nuclear detector is described. The generator can generate periodic single or double pulses of a user-defined amplitude and decay time, or randomly occurring pulses with amplitudes drawn at random from a user-prescribed probability density function. The electronics is based on a low power consumption Spartan-6 field-programmable gate array (FPGA) and a 14-bit digital to analog converter (DAC) running at frequency of 40 MHz, and a complete technical documentation to build the generator is available online.

  17. Pulse digital storage voltmeter for nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Belkin, V.S.; Kriger, Yu.G.

    1975-01-01

    An attachment to a digital frequency meter is described which operates jointly with a frequency meter as a digital voltmeter that measures the amplitude or the logarithm of the amplitudes of the input signal at the instant a synchronizing strobe-pulse appears. Storage of the amplitudes in digital form with a preset number of tored pulses is possible. The range of measurements is 0.1-18 V with an accuracy of +-0.25% for a strobe-pulse length 0.5-2μsec

  18. The SMPR for the naval propulsion

    International Nuclear Information System (INIS)

    Gauducheau, B.

    2002-01-01

    The first controlled application of the fissile energy was the american nuclear reactor for the ship propulsion. Since the sixties, the France begun researches to secure the independence of its nuclear propulsion program. The historical aspects, the french program management and the perspectives of the ship nuclear propulsion, are discussed in this paper. (A.L.B.)

  19. Propulsion Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Propulsion Lab simulates field test conditions in a controlled environment, using standardized or customized test procedures. The Propulsion Lab's 11 cells can...

  20. Nuclear propulsion: A vital technology for the exploration of Mars and the planets beyond

    Science.gov (United States)

    Borowski, Stanley K.

    1988-01-01

    The physics and technology issues and performance potential of various direct thrust fission and fusion propulsion concepts are examined. Next to chemical propulsion the solid core fission thermal rocket (SCR) is the olny other concept to be experimentally tested at the power (approx 1.5 to 5.0 GW) and thrust levels (approx 0.33 to 1.11 MN) required for manned Mars missions. With a specific impulse of approx 850 s, the SCR can perform various near-Earth, cislunar and interplanetary missions with lower mass and cost requirements than its chemical counterpart. The gas core fission thermal rocket, with a specific power and impulse of approx 50 kW/kg and 5000 s offers the potential for quick courier trips to Mars (of about 80 days) or longer duration exploration cargo missions (lasting about 280 days) with starting masses of about 1000 m tons. Convenient transportation to the outer Solar System will require the development of magnetic and inertial fusion rockets (IFRs). Possessing specific powers and impulses of approx 100 kW/kg and 200-300 kilosecs, IFRs will usher in the era of the true Solar System class speceship. Even Pluto will be accessible with roundtrip times of less than 2 years and starting masses of about 1500 m tons.

  1. Nuclear propulsion - A vital technology for the exploration of Mars and the planets beyond

    Science.gov (United States)

    Borowski, Stanley K.

    1989-01-01

    The physics and technology issues and performance potential of various direct thrust fission and fusion propulsion concepts are examined. Next to chemical propulsion the solid core fission thermal rocket (SCR) is the only other concept to be experimentally tested at the power (approx 1.5 to 5.0 GW) and thrust levels (approx 0.33 to 1.11 MN) required for manned Mars missions. With a specific impulse of approx 850 s, the SCR can perform various near-earth, cislunar and interplanetary missions with lower mass and cost requirements than its chemical counterpart. The gas core fission thermal rocket, with a specific power and impulse of approx 50 kW/kg and 5000 s offers the potential for quick courier trips to Mars (of about 80 days) or longer duration exploration cargo missions (lasting about 280 days) with starting masses of about 1000 m tons. Convenient transportation to the outer Solar System will require the development of magnetic and inertial fusion rockets (IFRs). Possessing specific powers and impulses of approx 100 kW/kg and 200-300 kilosecs, IFRs will usher in the era of the true Solar System class spaceship. Even Pluto will be accessible with roundtrip times of less than 2 years and starting masses of about 1500 m tons.

  2. Progress report on nuclear science and technology in China (Vol.1). Proceedings of academic annual meeting of China Nuclear Society in 2009, No.7--pulse power technology

    International Nuclear Information System (INIS)

    2010-11-01

    Progress report on nuclear science and technology in China (Vol. 1) includes 889 articles which are communicated on the first national academic annual meeting of China Nuclear Society. There are 10 books totally. This is the seventh one, the content is about nuclear electronics, nuclear detecting technology, pulse power technology, nuclear fusion and plasma

  3. Mission and system optimization of nuclear electric propulsion vehicles for lunar and Mars missions

    Science.gov (United States)

    Gilland, James H.

    1991-01-01

    The detailed mission and system optimization of low thrust electric propulsion missions is a complex, iterative process involving interaction between orbital mechanics and system performance. Through the use of appropriate approximations, initial system optimization and analysis can be performed for a range of missions. The intent of these calculations is to provide system and mission designers with simple methods to assess system design without requiring access or detailed knowledge of numerical calculus of variations optimizations codes and methods. Approximations for the mission/system optimization of Earth orbital transfer and Mars mission have been derived. Analyses include the variation of thruster efficiency with specific impulse. Optimum specific impulse, payload fraction, and power/payload ratios are calculated. The accuracy of these methods is tested and found to be reasonable for initial scoping studies. Results of optimization for Space Exploration Initiative lunar cargo and Mars missions are presented for a range of power system and thruster options.

  4. Digital pulse processing: new possibilities in nuclear spectroscopy

    International Nuclear Information System (INIS)

    Warburton, W.K.; Momayezi, M.; Hubbard-Nelson, B.; Skulski, W.

    2000-01-01

    Digital pulse processing is a signal processing technique in which detector (preamplifier output) signals are directly digitized and processed to extract quantities of interest. This approach has several significant advantages compared to traditional analog signal shaping. First, analyses can be developed which take pulse-by-pulse differences into account, as in making ballistic deficit compensations. Second, transient induced charge signals, which deposit no net charge on an electrode, can be analyzed to give, for example, information on the position of interaction within the detector. Third, deadtimes from transient overload signals are greatly reduced, from tens of μs to hundreds of ns. Fourth, signals are easily captured, so that more complex analyses can be postponed until the source event has been deemed 'interesting'. Fifth, signal capture and processing may easily be based on coincidence criteria between different detectors or different parts of the same detector. XIAs recently introduced CAMAC module, the DGF-4C, provides many of these features for four input channels, including two levels of digital processing and a FIFO for signal capture for each signal channel. The first level of digital processing is 'immediate', taking place in a gate array at the 40 MHz digitization rate, and implements pulse detection, pileup inspection, trapezoidal energy filtering, and control of an external 25.6 μs long FIFO. The second level of digital processing is provided by a digital signal processor (DSP), where more complex algorithms can be implemented. To illustrate digital pulse processing's possibilities, we describe the application of the DGF-4C to a series of experiments. The first, for which the DGF was originally developed, involves locating gamma-ray interaction sites within large segmented Ge detectors. The goal of this work is to attain spatial resolutions of order 2 mm σ within 70 mm x 90 mm detectors. We show how pulse shape analysis allows ballistic

  5. Electronic constant current and current pulse signal generator for nuclear instrumentation testing

    Science.gov (United States)

    Brown, R.A.

    1994-04-19

    Circuitry is described for testing the ability of an intermediate range nuclear instrument to detect and measure a constant current and a periodic current pulse. The invention simulates the resistance and capacitance of the signal connection of a nuclear instrument ion chamber detector and interconnecting cable. An LED flasher/oscillator illuminates an LED at a periodic rate established by a timing capacitor and circuitry internal to the flasher/oscillator. When the LED is on, a periodic current pulse is applied to the instrument. When the LED is off, a constant current is applied. An inductor opposes battery current flow when the LED is on. 1 figures.

  6. Response on the earth surface due to illumination by electromagnetic pulse of nuclear explosion

    International Nuclear Information System (INIS)

    Nesic, R.

    1983-01-01

    Electromagnetic pulse is one of environment responses to extitation by nuclear explosion, its influence on the surface of the earth is most expressed in case of a nuclear explosion in ionosphere. For electromagnetic pulse of ionospheric explosion the time response, spectrum, spectral distribution and integral flux of energy on the earth surface were analysed, responses to them in shape of conductive voltage and currents were defined. Obtained shapes of responses and their range of variation are the base to define requirements for needed and justified protections. (author)

  7. Effluent Scrubbing of Engine Exhaust of a Nuclear Thermal Propulsion Engine

    Data.gov (United States)

    National Aeronautics and Space Administration — The Institute for Clean Energy Technology (ICET) at MSU already supports long-standing high-efficiency nuclear particulate air (HEPA) filtration research as well as...

  8. The SMPR for the naval propulsion; Les RPMP pour la propulsion navale

    Energy Technology Data Exchange (ETDEWEB)

    Gauducheau, B. [Technicatome, Centre d' Etudes Nucleaires de Saclay, 91 - Gif sur Yvette (France)

    2002-07-01

    The first controlled application of the fissile energy was the american nuclear reactor for the ship propulsion. Since the sixties, the France begun researches to secure the independence of its nuclear propulsion program. The historical aspects, the french program management and the perspectives of the ship nuclear propulsion, are discussed in this paper. (A.L.B.)

  9. Propulsion of a flat tin target with pulsed CO2 laser radiation: measurements using a ballistic pendulum

    Science.gov (United States)

    Lakatosh, B. V.; Abramenko, D. B.; Ivanov, V. V.; Medvedev, V. V.; Krivtsun, V. M.; Koshelev, K. N.; Yakunin, A. M.

    2018-01-01

    The recoil momentum transfer produced by irradiation of a flat tin (Sn) target with pulses of high-power CO2 laser with intensity ranging from 107 to 1010 W cm-2 has been studied. Momentum measurements were performed using a ballistic pendulum, capable of measuring momenta as small as 0.001 g · cm s-1 . It has been established that the recoil momentum monotonically increases with the laser energy and asymptotically reaches the power scaling law p ∼ Iα with α = 0.96 +/- 0.07 . Results are compared with previously published theoretical studies.

  10. About a fuel for burnup reactor of periodical pulsed nuclear pumped laser

    International Nuclear Information System (INIS)

    Volkov, A.I.; Lukin, A.V.; Magda, L.E.; Magda, E.P.; Pogrebov, I.S.; Putnikov, I.S.; Khmelnitsky, D.V.; Scherbakov, A.P.

    1998-01-01

    A physical scheme of burnup reactor for a Periodic Pulsed Nuclear Pumped Laser was supposed. Calculations of its neutron physical parameters were made. The general layout and construction of basic elements of the reactor are discussed. The requirements for the fuel and fuel elements are established. (author)

  11. The separation of heavy ion tracks in nuclear emulsions by means of the pulsed electric field

    International Nuclear Information System (INIS)

    Akopova, A.B.; Magradze, N.V.; Melkumyan, L.V.; Prokhorenko, Y.P.

    1976-01-01

    The pulsed electric field (PEF) technique is developed for the separation of heavy ion tracks from the intense background caused by high energy electrons, protons and γ-radiation. The tracks of Ne, Cr, Ar-ions accelerated at the Dubna Nuclear Reactions Laboratory have been separated from the background, the voltage of the applied PEF being 10 5 V/cm. (orig.) [de

  12. Pulse pile-up in nuclear particle detection systems with rapidly varying counting rates

    International Nuclear Information System (INIS)

    Datlowe, D.W.

    1977-01-01

    Pulse pile-up in nuclear particle detection systems is the distortion of the measured pulse height distribution which occurs when there is a significant probability that more than one particle will arrive within the detector resolving time. This paper treats the problem in cases where the probability of pile-up varies on a time scale comparable to the rise time of the detector system electronics. These variations introduce structure into the pulse height distributions which cannot occur for a time-independent pile-up probability. Three classes of problems which exemplify these effects are as follows: 1) Pile-up rejection circuits. 2) Cascaded nuclear decays, in which the lifetime for emission of a second X-ray is comparable to the detector rise time. 3) Bursts of particles where the intensity is modulated on a time scale comparable to the detector rise time. These problems are solved computationally by an extension of a numerical technique previously developed. (Auth.)

  13. Realizing "2001: A Space Odyssey": Piloted Spherical Torus Nuclear Fusion Propulsion

    Science.gov (United States)

    Williams, Craig H.; Dudzinski, Leonard A.; Borowski, Stanley K.; Juhasz, Albert J.

    2005-01-01

    A conceptual vehicle design enabling fast, piloted outer solar system travel was created predicated on a small aspect ratio spherical torus nuclear fusion reactor. The initial requirements were satisfied by the vehicle concept, which could deliver a 172 mt crew payload from Earth to Jupiter rendezvous in 118 days, with an initial mass in low Earth orbit of 1,690 mt. Engineering conceptual design, analysis, and assessment was performed on all major systems including artificial gravity payload, central truss, nuclear fusion reactor, power conversion, magnetic nozzle, fast wave plasma heating, tankage, fuel pellet injector, startup/re-start fission reactor and battery bank, refrigeration, reaction control, communications, mission design, and space operations. Detailed fusion reactor design included analysis of plasma characteristics, power balance/utilization, first wall, toroidal field coils, heat transfer, and neutron/x-ray radiation. Technical comparisons are made between the vehicle concept and the interplanetary spacecraft depicted in the motion picture 2001: A Space Odyssey.

  14. A Spherical Torus Nuclear Fusion Reactor Space Propulsion Vehicle Concept for Fast Interplanetary Travel

    Science.gov (United States)

    Williams, Craig H.; Borowski, Stanley K.; Dudzinski, Leonard A.; Juhasz, Albert J.

    1998-01-01

    A conceptual vehicle design enabling fast outer solar system travel was produced predicated on a small aspect ratio spherical torus nuclear fusion reactor. Initial requirements were for a human mission to Saturn with a greater than 5% payload mass fraction and a one way trip time of less than one year. Analysis revealed that the vehicle could deliver a 108 mt crew habitat payload to Saturn rendezvous in 235 days, with an initial mass in low Earth orbit of 2,941 mt. Engineering conceptual design, analysis, and assessment was performed on all ma or systems including payload, central truss, nuclear reactor (including divertor and fuel injector), power conversion (including turbine, compressor, alternator, radiator, recuperator, and conditioning), magnetic nozzle, neutral beam injector, tankage, start/re-start reactor and battery, refrigeration, communications, reaction control, and in-space operations. Detailed assessment was done on reactor operations, including plasma characteristics, power balance, power utilization, and component design.

  15. Materials processing, pulsed field magnetization and field-pole application to propulsion motors on Gd123 bulk superconductors

    International Nuclear Information System (INIS)

    Izumi, M; Xu, C; Xu, Y; Morita, E; Kimura, Y; Hu, A; Ichihara, M; Murakami, M; Sakai, N; Hirabayashi, I; Sugimoto, H; Miki, M

    2008-01-01

    Gd123 bulk superconductor is one of the promising magnet materials. We studied the materials processing to grow high performance magnet with a doping of nano-sized metal oxides such as ZrO 2 as a candidature of pinning centre. The enhancement of the critical current density was obtained. Growth of nano-sized particles of Gd211 in addition to BaZrO 3 were observed by TEM. The formation of nano-sized particles appears a key to improve the integrated flux trapped inside the bulks and the TEM reveals an intriguing effect of the addition to the microstructure of bulk materials. Magnetization process is crucial especially for an extended machinery. Pulsed field magnetization was applied to the field-pole bulk on the rotor disk of the tested synchronous motor. The trapped flux density of 1.3 T for Gd123 bulk sample and of 60 mm diameter was reached in the limited dimension of the tested motor by a step cooling method down to 38 K with a closed-cycle condensed neon. The pulsed magnetic field was applied with a new type of split-armature coil. A large bulk of 140 mm diameter has also shown a potential flux trapping superior to other smaller specimens. The bulk magnet provides a strong magnetic field around the bulk body itself with high current density relative to a coil winding. A comparative drawing of a 'torque density' of a variety of motors which is defined as the torque divided by the volume of the motor indicates a potential advantage of bulk motor as a super permanent magnet motor

  16. Space transfer concepts and analysis for exploration missions. Implementation plan and element description document (draft final). Volume 5: Nuclear electric propulsion vehicle

    Science.gov (United States)

    1991-01-01

    The nuclear electric propulsion (NEP) concept design developed in support of the Space Transfer Concepts and Analysis for Exploration Missions (STCAEM) study is presented. The evolution of the NEP concept is described along with the requirements, guidelines, and assumptions for the design. Operating modes and options are defined and a systems description of the vehicle is presented. Artificial gravity configuration options and space and ground support systems are discussed. Finally, an implementation plan is presented which addresses technology needs, schedules, facilities and costs.

  17. High Temperature Nanocomposites For Nuclear Thermal Propulsion and In-Space Fabrication by Hyperbaric Pressure Laser Chemical Vapor Deposition

    Science.gov (United States)

    Maxwell, J. L.; Webb, N. D.; Espinoza, M.; Cook, S.; Houts, M.; Kim, T.

    Nuclear Thermal Propulsion (NTP) is an indispensable technology for the manned exploration of the solar system. By using Hyperbaric Pressure Laser Chemical Vapor Deposition (HP-LCVD), the authors propose to design and build a promising next-generation fuel element composed of uranium carbide UC embedded in a latticed matrix of highly refractory Ta4HfC5 for an NTP rocket capable of sustaining temperatures up to 4000 K, enabling an Isp of up to 1250 s. Furthermore, HP-LCVD technology can also be harnessed to enable 3D rapid prototyping of a variety of materials including metals, ceramics and composites, opening up the possibility of in-space fabrication of components, replacement parts, difficult-to-launch solar sails and panels and a variety of other space structures. Additionally, rapid prototyping with HP-LCVD makes a feasible "live off the land" strategy of interplanetary and interstellar exploration ­ the precursors commonly used in the technology are found, often in abundance, on other solar system bodies either as readily harvestable gas (e.g. methane) or as a raw material that could be converted into a suitable precursor (e.g. iron oxide into ferrocene on Mars).

  18. Steady-state thermal-hydraulic analysis of the pellet-bed reactor for nuclear thermal propulsion

    International Nuclear Information System (INIS)

    El-Genk, M.S.; Morley, N.J.; Yang, J.Y.

    1992-01-01

    The pellet-bed reactor (PBR) for nuclear thermal propulsion is a hydrogen-cooled, BeO-reflected, fast reactor, consisting of an annular core region filled with randomly packed, spherical fuel pellets. The fuel pellets in the PBR are self-supported, eliminating the need for internal core structure, which simplifies the core design and reduces the size and mass of the reactor. Each spherical fuel pellet is composed of hundreds of fuel microspheres embedded in a zirconium carbide (ZrC) matrix. Each fuel microsphere is composed of a UC-NbC fuel kernel surrounded by two consecutive layers of the NbC and ZrC. Gaseous hydrogen serves both as core coolant and as the propellant for the PBR rocket engine. The cold hydrogen flows axially down the inlet channel situated between the core and the external BeO reflector and radially through the orifices in the cold frit, the core, and the orifices in the hot frit. Finally, the hot hydrogen flows axially out the central channel and exits through converging-diverging nozzle. A thermal-hydraulic analysis of the PBR core was performed with an emphasis on optimizing the size and axial distribution of the orifices in the hot and cold frits to ensure that hot spots would not develop in the core during full-power operation. Also investigated was the validity of the assumptions of neglecting the axial conduction and axial cross flow in the core

  19. Pulse Design in Solid-State Nuclear Magnetic Resonance

    DEFF Research Database (Denmark)

    Palani, Ravi Shankar

    The work presented in this dissertation is centred on the theory of experimental methods in solid-state Nuclear Magnetic Resonance (NMR) spectroscopy, which deals with interaction of electromagnetic radiation with nuclei in a magnetic field and possessing a fundamental quantum mechanical property...... been discussed in the past in literature. Generalised expressions for the effective Hamiltonian using AHT are derived in the frequency domain in this dissertation, to allow for appreciation of the equivalence with Floquet theory mediated effective Hamiltonian. The derivation relies on the ability...

  20. Mathematical model for the preliminary analysis of dual-mode space nuclear fission solid core power and propulsion systems, NUROC3A. AMS report No. 1239a

    Energy Technology Data Exchange (ETDEWEB)

    Grey, J.; Chow, S.

    1976-06-30

    The three-volume report describes a dual-mode nuclear space power and propulsion system concept that employs an advanced solid-core nuclear fission reactor coupled via heat pipes to one of several electric power conversion systems. Such a concept could be particularly useful for missions which require both relatively high acceleration (e.g., for planetocentric maneuvers) and high performance at low acceleration (e.g., on heliocentric trajectories or for trajectory shaping). The first volume develops the mathematical model of the system.

  1. MW-Class Electric Propulsion System Designs

    Science.gov (United States)

    LaPointe, Michael R.; Oleson, Steven; Pencil, Eric; Mercer, Carolyn; Distefano, Salvador

    2011-01-01

    Electric propulsion systems are well developed and have been in commercial use for several years. Ion and Hall thrusters have propelled robotic spacecraft to encounters with asteroids, the Moon, and minor planetary bodies within the solar system, while higher power systems are being considered to support even more demanding future space science and exploration missions. Such missions may include orbit raising and station-keeping for large platforms, robotic and human missions to near earth asteroids, cargo transport for sustained lunar or Mars exploration, and at very high-power, fast piloted missions to Mars and the outer planets. The Advanced In-Space Propulsion Project, High Efficiency Space Power Systems Project, and High Power Electric Propulsion Demonstration Project were established within the NASA Exploration Technology Development and Demonstration Program to develop and advance the fundamental technologies required for these long-range, future exploration missions. Under the auspices of the High Efficiency Space Power Systems Project, and supported by the Advanced In-Space Propulsion and High Power Electric Propulsion Projects, the COMPASS design team at the NASA Glenn Research Center performed multiple parametric design analyses to determine solar and nuclear electric power technology requirements for representative 300-kW class and pulsed and steady-state MW-class electric propulsion systems. This paper describes the results of the MW-class electric power and propulsion design analysis. Starting with the representative MW-class vehicle configurations, and using design reference missions bounded by launch dates, several power system technology improvements were introduced into the parametric COMPASS simulations to determine the potential system level benefits such technologies might provide. Those technologies providing quantitative system level benefits were then assessed for technical feasibility, cost, and time to develop. Key assumptions and primary

  2. Development of digital pulse processing spectrometer for online analysis of nuclear physics detectors

    International Nuclear Information System (INIS)

    Sun Jian; Xie Shuxin; Liang Hao; Yu Xiaoqi

    2010-01-01

    An application of double-channels digital pulse processing spectrometer is presented which used for nanosecond time determinations and energy measurements with nuclear physics detectors. Each channel features a 14-bit 125 Mhz Samples/s ADC for fast sampling signals, FPGA controls the whole system and connects the computer with USB2.0 interface, transfers the sampled data to DSP for online data analysis. A few algorithms have been simulated by Matlab and successfully tested on Agilent 33250A Function/Arbitrary Waveform Generator, implementing FIR lowpass Filter, pulse shape reconstruction, amplitude peak search, digital constraint fraction timing. (authors)

  3. Basic Research in Electric Propulsion. Part I: Pulsed Plasma Thruster Propellant Efficiency and Contamination. Part II: Arcjet Remote Plume Measurement and Hydrogen Density

    National Research Council Canada - National Science Library

    Pobst, J

    2002-01-01

    .... Arcjet technology is also under investigation with Electric Propulsion Space Experiment Optical Signature experiments underway and Multiphoton Laser Induced Fluorescence Measurements of Ground State...

  4. Preliminary Thermohydraulic Analysis of a New Moderated Reactor Utilizing an LEU-Fuel for Space Nuclear Thermal Propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Seung Hyun; Choi, Jae Young; Venneria, Paolo F.; Jeong, Yong Hoon; Chang, Soon Heung [KAIST, Daejeon (Korea, Republic of)

    2015-10-15

    The Korea Advanced NUclear Thermal Engine Rocket utilizing an LEU fuel (KANUTER-LEU) is a non-proliferative and comparably efficient NTR engine with relatively low thrust levels of 40 - 50 kN for in-space transportation. The small modular engine can expand mission versatility, when flexibly used in a clustered engine arrangement, so that it can perform various scale missions from low-thrust robotic science missions to high-thrust manned missions. In addition, the clustered engine system can enhance engine redundancy and ensuing crew safety as well as the thrust. The propulsion system is an energy conversion system to transform the thermal energy of the reactor into the kinetic energy of the propellant to produce the powers for thrust, propellant feeding and electricity. It is mainly made up of a propellant Feeding System (PFS) comprising a Turbo-Pump Assembly (TPA), a Regenerative Nozzle Assembly (RNA), etc. For this core design study, an expander cycle is assumed to be the propulsion system. The EGS converts the thermal energy of the EHTGR in the idle operation (only 350 kW{sub th} power) to electric power during the electric power mode. This paper presents a preliminary thermohydraulic design analysis to explore the design space for the new reactor and to estimate the referential engine performance. The new non-proliferative NTR engine concept, KANUTER-LEU, is under designing to surmount the nuclear proliferation obstacles on allR and Dactivities and eventual commercialization for future generations. To efficiently implement a heavy LEU fuel for the NTR engine, its reactor design innovatively possesses the key characteristics of the high U density fuel with high heating and H{sub 2} corrosion resistances, the thermal neutron spectrum core and also minimizing non-fission neutron loss, and the compact reactor design with protectively cooling capability. To investigate feasible design space for the moderated EHTGR-LEU and resultant engine performance, the

  5. Enabling surface nuclear magnetic resonance at high-noise environments using a pre-polarization pulse

    Science.gov (United States)

    Lin, Tingting; Yang, Yujing; Teng, Fei; Müller-Petke, Mike

    2018-02-01

    The technique of surface nuclear magnetic resonance (SNMR) has been widely used for hydrological investigations in recent years. Unfortunately, the detected SNMR signals are limited to tens of nanovolts and are thus susceptible to environmental noise. While pre-polarization pulses to enhance the detected signal amplitudes are common in laboratory applications, SNMR field testing has only utilized excitation pulses until now. In conducting measurements in China, we demonstrate that adding a pre-polarization field to the SNMR pulse sequence is feasible and allows for the reliable detection of SNMR signals in noisy scenarios that otherwise prohibit signal detection. We introduce a forward modelling for pre-polarization using SNMR and present a three-layer model obtained from inverse modelling that satisfies the observed data from the field experiment. We expect this development to open up new applications for SNMR technology, especially in high-noise level places, such as active mines.

  6. Performance of the beam pulsing system of the 15 UD Pelletron accelerator at Nuclear Science Centre

    International Nuclear Information System (INIS)

    Joshi, R.; Barua, P.; Jha, V.; Sarkar, A.; Ghosh, S.; Bhowmik, R.K.

    1997-01-01

    The Electrostatic International Incorporation (EII), USA supplied beam pulsing system of the 15 UD Pelletron accelerator at Nuclear Science Centre consists of mainly three components viz. a chopper, a travelling wave deflector (TWD) and a buncher. The chopper is used to chop the dc beam into small portions at the repetition rate of 4 MHz. The function of TWD is to achieve the eleven different repetition rates other than 4 MHz and the buncher finally bunches the chopped beam from the chopper. The performance of this beam pulsing system improved considerably after incorporating a line voltage stabilizer to the system electronics and modifying the feedback loop of the system. The performance of TWD was also improved after some modification in its operation and adding an interlock circuit to TWD electronics. A spiral cavity is now installed in the vault area after the analyzing magnet for the efficient measurement of time resolution of the pulsed beam. (author). 2 refs., 4 figs., 1 tab

  7. Industrial pulse columns design for uranium purification of nuclear grade, by the indirect HTU method

    International Nuclear Information System (INIS)

    Franca Junior, J.M.; Messano, J.

    1974-01-01

    A study about the necessary parameters in the measurement of three industrial pulsed columns set, with their pulse generator of conventional mechanic type, for an average/year production of 500 tons in high uranium purity for nuclear designs, is done. The diameters of the columns as a function of organic and aqueous phase flows were calculated. The calculation of the unity transfer number for each column type was detailed, through the graphic integration method. It was possible to arrive to the columns HTU under project, getting later the heights of those columns. Plottings were prepared with operation and equilibrium curves gotten in laboratory works, which were used later for the HTU'S calculation. A demonstration of the adopted pulse conditions, with generator's measurement, necessary power and limit frequency of operation in function of pressures existing in the system, was made [pt

  8. On the electromagnetic pulse generated by exo-atmospheric nuclear detonations

    International Nuclear Information System (INIS)

    Leuthaeuser, K.D.

    1983-01-01

    When gamma rays produced by high altitude nuclear weapons explosions interact with the atmosphere they generate an electromagnetic pulse (EMP) propagating towards the earth's surface. The EMP covers large areas of millions of km 2 and reaches peak electric fields of more than 50 kV/m which may couple into all kinds of conducting systems. The present paper deals with a simple model to calculate EMP fields basing on Maxwell's equations. (orig.)

  9. Pulsed-field gradient nuclear magnetic resonance study of transport properties of fluid catalytic cracking catalysts

    Czech Academy of Sciences Publication Activity Database

    Kortunov, P.; Vasenkov, S.; Kärger, J.; Fé Elía, M.; Perez, M.; Stöcker, M.; Papadopoulos, G. K.; Theodorou, D.; Drescher, B.; McElhiney, G.; Bernauer, B.; Krystl, V.; Kočiřík, Milan; Zikánová, Arlette; Jirglová, Hana; Berger, C.; Gläser, R.; Weitkamp, J.; Hansen, E. W.

    2005-01-01

    Roč. 23, č. 2 (2005), s. 233-237 ISSN 0730-725X Grant - others:TROCAT project - European Community(DE) G5RD-CT-2001-00520 Institutional research plan: CEZ:AV0Z40400503 Keywords : pulsed-field gradient * nuclear magnetic resonance * fluid catalytic cracking catalyst Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.361, year: 2005

  10. The Nuclear Thermal Propulsion Stage (NTPS): A Key Space Asset for Human Exploration and Commercial Missions to the Moon

    Science.gov (United States)

    Borowski, Stanley K.; McCurdy, David R.; Burke, Laura M.

    2014-01-01

    The nuclear thermal rocket (NTR) has frequently been discussed as a key space asset that can bridge the gap between a sustained human presence on the Moon and the eventual human exploration of Mars. Recently, a human mission to a near Earth asteroid (NEA) has also been included as a "deep space precursor" to an orbital mission of Mars before a landing is attempted. In his "post-Apollo" Integrated Space Program Plan (1970 to 1990), Wernher von Braun, proposed a reusable Nuclear Thermal Propulsion Stage (NTPS) to deliver cargo and crew to the Moon to establish a lunar base initially before sending human missions to Mars. The NTR was selected because it was a proven technology capable of generating both high thrust and high specific impulse (Isp approx. 900 s)-twice that of today's best chemical rockets. During the Rover and NERVA programs, 20 rocket reactors were designed, built and successfully ground tested. These tests demonstrated the (1) thrust levels; (2) high fuel temperatures; (3) sustained operation; (4) accumulated lifetime; and (5) restart capability needed for an affordable in-space transportation system. In NASA's Mars Design Reference Architecture (DRA) 5.0 study, the "Copernicus" crewed NTR Mars transfer vehicle used three 25 klbf "Pewee" engines-the smallest and highest performing engine tested in the Rover program. Smaller lunar transfer vehicles-consisting of a NTPS with three approx. 16.7 klbf "SNRE-class" engines, an in-line propellant tank, plus the payload-can be delivered to LEO using a 70 t to LEO upgraded SLS, and can support reusable cargo delivery and crewed lunar landing missions. The NTPS can play an important role in returning humans to the Moon to stay by providing an affordable in-space transportation system that can allow initial lunar outposts to evolve into settlements capable of supporting commercial activities. Over the next decade collaborative efforts between NASA and private industry could open up new exploration and commercial

  11. Nuclear Thermal Propulsion (NTP): A Proven, Growth Technology for Fast Transit Human Missions to Mars

    Science.gov (United States)

    Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2014-01-01

    The "fast conjunction" long surface stay mission option was selected for NASA's recent Mars Design Reference Architecture (DRA) 5.0 study because it provided adequate time at Mars (approx. 540 days) for the crew to explore the planet's geological diversity while also reducing the "1-way" transit times to and from Mars to approx. 6 months. Short transit times are desirable in order to reduce the debilitating physiological effects on the human body that can result from prolonged exposure to the zero-gravity (0-gE) and radiation environments of space. Recent measurements from the RAD detector attached to the Curiosity rover indicate that astronauts would receive a radiation dose of approx. 0.66 Sv (approx. 66 rem)-the limiting value established by NASA-during their 1-year journey in deep space. Proven nuclear thermal rocket (NTR) technology, with its high thrust and high specific impulse (Isp approx. 900 s), can cut 1-way transit times by as much as 50 percent by increasing the propellant capacity of the Mars transfer vehicle (MTV). No large technology scale-ups in engine size are required for these short transit missions either since the smallest engine tested during the Rover program-the 25 klbf "Pewee" engine is sufficient when used in a clustered arrangement of three to four engines. The "Copernicus" crewed MTV developed for DRA 5.0 is a 0-gE design consisting of three basic components: (1) the NTP stage (NTPS); (2) the crewed payload element; and (3) an integrated "saddle truss" and LH2 propellant drop tank assembly that connects the two elements. With a propellant capacity of approx. 190 t, Copernicus can support 1-way transit times ranging from approx. 150 to 220 days over the 15-year synodic cycle. The paper examines the impact on vehicle design of decreasing transit times for the 2033 mission opportunity. With a fourth "upgraded" SLS/HLV launch, an "in-line" LH2 tank element can be added to Copernicus allowing 1-way transit times of 130 days. To achieve 100

  12. Cryogenic Propulsion

    Data.gov (United States)

    National Aeronautics and Space Administration — Cryogenic propellants can enhance NASA missions. This project will establish that modern cryogenic storage technologies will allow the use of cryogenic propulsion...

  13. Vehicle with inclinable caterpillar propulsion units

    International Nuclear Information System (INIS)

    Clar, G.

    1991-01-01

    This vehicle usable in hostile environment such nuclear industry has four propulsion units with a caterpillar track and two integrated motors: one for advancing the caterpillar track and the other for inclining the propulsion unit when overcoming obstacles. Each propulsion unit is easily replaceable because there are no mechanical parts in the body of the vehicle [fr

  14. Z-Pinch Fusion Propulsion

    Science.gov (United States)

    Miernik, Janie

    2011-01-01

    Fusion-based nuclear propulsion has the potential to enable fast interplanetary transportation. Shorter trips are better for humans in the harmful radiation environment of deep space. Nuclear propulsion and power plants can enable high Ispand payload mass fractions because they require less fuel mass. Fusion energy research has characterized the Z-Pinch dense plasma focus method. (1) Lightning is form of pinched plasma electrical discharge phenomena. (2) Wire array Z-Pinch experiments are commonly studied and nuclear power plant configurations have been proposed. (3) Used in the field of Nuclear Weapons Effects (NWE) testing in the defense industry, nuclear weapon x-rays are simulated through Z-Pinch phenomena.

  15. Computer code and users' guide for the preliminary analysis of dual-mode space nuclear fission solid core power and propulsion systems, NUROC3A. AMS report No. 1239b

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, R.A.; Smith, W.W.

    1976-06-30

    The three-volume report describes a dual-mode nuclear space power and propulsion system concept that employs an advanced solid-core nuclear fission reactor coupled via heat pipes to one of several electric power conversion systems. The second volume describes the computer code and users' guide for the preliminary analysis of the system.

  16. Request for Naval Reactors Comment on Proposed PROMETHEUS Space Flight Nuclear Reactor High Tier Reactor Safety Requirements and for Naval Reactors Approval to Transmit These Requirements to Jet Propulsion Laboratory

    International Nuclear Information System (INIS)

    D. Kokkinos

    2005-01-01

    The purpose of this letter is to request Naval Reactors comments on the nuclear reactor high tier requirements for the PROMETHEUS space flight reactor design, pre-launch operations, launch, ascent, operation, and disposal, and to request Naval Reactors approval to transmit these requirements to Jet Propulsion Laboratory to ensure consistency between the reactor safety requirements and the spacecraft safety requirements. The proposed PROMETHEUS nuclear reactor high tier safety requirements are consistent with the long standing safety culture of the Naval Reactors Program and its commitment to protecting the health and safety of the public and the environment. In addition, the philosophy on which these requirements are based is consistent with the Nuclear Safety Policy Working Group recommendations on space nuclear propulsion safety (Reference 1), DOE Nuclear Safety Criteria and Specifications for Space Nuclear Reactors (Reference 2), the Nuclear Space Power Safety and Facility Guidelines Study of the Applied Physics Laboratory

  17. Permeabilization of the nuclear envelope following nanosecond pulsed electric field exposure

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Gary L., E-mail: gary.l.thompson.3@gmail.com [Oak Ridge Institute for Science & Education, Joint Base San Antonio Fort Sam Houston, TX, 78234 (United States); Roth, Caleb C. [Department of Radiological Sciences, University of Texas Health Science Center at San Antonio, TX, 78234 (United States); Kuipers, Marjorie A. [Radio Frequency Radiation Branch, Bioeffects Division, Human Effectiveness Directorate, 711th Human Performance Wing, Air Force Research Laboratory, Joint Base San Antonio Fort Sam Houston, TX, 78234 (United States); Tolstykh, Gleb P. [General Dynamics IT, Joint Base San Antonio Fort Sam Houston, TX, 78234 (United States); Beier, Hope T. [Optical Radiation Branch, Bioeffects Division, Human Effectiveness Directorate, 711th Human Performance Wing, Air Force Research Laboratory, Joint Base San Antonio Fort Sam Houston, TX, 78234 (United States); Ibey, Bennett L. [Radio Frequency Radiation Branch, Bioeffects Division, Human Effectiveness Directorate, 711th Human Performance Wing, Air Force Research Laboratory, Joint Base San Antonio Fort Sam Houston, TX, 78234 (United States)

    2016-01-29

    Permeabilization of cell membranes occurs upon exposure to a threshold absorbed dose (AD) of nanosecond pulsed electric fields (nsPEF). The ultimate, physiological bioeffect of this exposure depends on the type of cultured cell and environment, indicating that cell-specific pathways and structures are stimulated. Here we investigate 10 and 600 ns duration PEF effects on Chinese hamster ovary (CHO) cell nuclei, where our hypothesis is that pulse disruption of the nuclear envelope membrane leads to observed cell death and decreased viability 24 h post-exposure. To observe short-term responses to nsPEF exposure, CHO cells have been stably transfected with two fluorescently-labeled proteins known to be sequestered for cellular chromosomal function within the nucleus – histone-2b (H2B) and proliferating cell nuclear antigen (PCNA). H2B remains associated with chromatin after nsPEF exposure, whereas PCNA leaks out of nuclei permeabilized by a threshold AD of 10 and 600 ns PEF. A downturn in 24 h viability, measured by MTT assay, is observed at the number of pulses required to induce permeabilization of the nucleus. - Highlights: • The ability of nsPEF to damage nuclear structures within cells is investigated. • Leakage of proliferating nuclear antigen from nuclei is induced by nsPEF. • High doses of nsPEF disrupt cortical lamin and cause chromatin decompaction. • Histone H2B remains attached to chromatin following nsPEF exposure. • DNA does not leak out of nsPEF-permeabilized nuclei.

  18. Frequency-agile gyrotron for electron decoupling and pulsed dynamic nuclear polarization

    Science.gov (United States)

    Scott, Faith J.; Saliba, Edward P.; Albert, Brice J.; Alaniva, Nicholas; Sesti, Erika L.; Gao, Chukun; Golota, Natalie C.; Choi, Eric J.; Jagtap, Anil P.; Wittmann, Johannes J.; Eckardt, Michael; Harneit, Wolfgang; Corzilius, Björn; Th. Sigurdsson, Snorri; Barnes, Alexander B.

    2018-04-01

    We describe a frequency-agile gyrotron which can generate frequency-chirped microwave pulses. An arbitrary waveform generator (AWG) within the NMR spectrometer controls the microwave frequency, enabling synchronized pulsed control of both electron and nuclear spins. We demonstrate that the acceleration of emitted electrons, and thus the microwave frequency, can be quickly changed by varying the anode voltage. This strategy results in much faster frequency response than can be achieved by changing the potential of the electron emitter, and does not require a custom triode electron gun. The gyrotron frequency can be swept with a rate of 20 MHz/μs over a 670 MHz bandwidth in a static magnetic field. We have already implemented time-domain electron decoupling with dynamic nuclear polarization (DNP) magic angle spinning (MAS) with this device. In this contribution, we show frequency-swept DNP enhancement profiles recorded without changing the NMR magnet or probe. The profile of endofullerenes exhibits a DNP profile with a <10 MHz linewidth, indicating that the device also has sufficient frequency stability, and therefore phase stability, to implement pulsed DNP mechanisms such as the frequency-swept solid effect. We describe schematics of the mechanical and vacuum construction of the device which includes a novel flanged sapphire window assembly. Finally, we discuss how commercially available continuous-wave gyrotrons can potentially be converted into similar frequency-agile high-power microwave sources.

  19. The project of the submarine of nuclear propulsion under the optics of its protagonists: an historical analysis from Geisel to Lula 1974 - 2009

    International Nuclear Information System (INIS)

    Correa, Fernanda das Gracas

    2009-01-01

    This work is a historical analysis of the project of construction of the submarine of nuclear propulsion under the optics of the people who direct or had indirectly become involved themselves with it. Geisel undertook a more autonomous type of politics. The Europe started to be the strategical region for the acquisition of nuclear technology. The only favorable country transfer nuclear technology to Brazil was the Federal Republic of Germany (FRG). The idea to construct a nuclear submarine is product of the negotiations between authorities of Brazilian politics and political, diplomatical, scientific and business authorities of the FRG. In 1978, the engineer Othon Luiz Pinheiro da Silva came back to Brazil after completing his doctorate in nuclear technology in the MIT. Commander Othon developed the idea to construct a nuclear submarine in the Brazilian Navy. Due to the events in the national and in the international scenario, Geisel decided to construct the nuclear submarine, but he opted to allow the Brazilian Navy to lead this construction. Although Geisel sketched a project of naval nuclear propulsion, it was the project elaborated by commander Othon which became the nuclear project of the Brazilian Navy. In order to prevent international attention toward this work, Geisel guided it for the subversion. This way, the idea to construct a nuclear submarine ceases to belong to the Brazilian nuclear program to become parallel nuclear program. When Figueiredo became president he kept the diversification politics of partnerships, kept the nuclear Agreement Brazil-FRG in 1975 and kept the project of construction of a nuclear reactor. Figueiredo, after observing the performance of the English nuclear submarines in the south Atlantic and to perceive the real intentions of U.S.A. towards Brazil, Figueiredo decided to support politically and financially and the project of construction of the nuclear submarine. Despite all aversion that Figueiredo had in relation to

  20. Intense resonance neutron source (IREN) - new pulsed source for nuclear physical and applied investigations

    International Nuclear Information System (INIS)

    Anan'ev, V.D.; Furman, W.I.; Kobets, V.V.; Meshkov, I.N.; Pyataev, V.G.; Shirkov, G.D.; Shvets, V.A.; Sumbaev, A.P.; Kuatbekov, R.P.; Tret'yakov, I.T.; Frolov, A.R.; Gurov, S.M.; Logachev, P.V.; Pavlov, V.M.; Skarbo, B.A.

    2005-01-01

    An accelerator-driven subcritical system (200 MeV electron linac + metallic plutonium subcritical core) IREN is constructed at the Joint Institute for Nuclear Research (JINR). The new pulsed neutron source IREN is optimized for maximal yield of resonance neutrons (1-10 5 eV). The S-band electron linac with a pulse duration near 200 ns, repetition rate up to 150 Hz and the mean beam power 10 kW delivers 200-MeV electrons onto a specially designed tungsten target (an electron-neutron converter) situated in the center of a very compact and fast subcritical assembly with K eff 15 per second. A mean fission power of the multiplying target is planned to be near 15 kW. The current status of the project is presented

  1. Thermal mixing in multiple-pulse nuclear quadrupole resonance spin-locking

    International Nuclear Information System (INIS)

    Beltjukov, P A; Kibrik, G E; Furman, G B; Goren, S D

    2007-01-01

    We report on an experimental and theoretical nuclear quadrupole resonance (NQR) multiple-pulse spin-locking study of the thermal mixing process in solids containing nuclei of two different sorts, I>1/2 and S = 1/2, coupled by dipole-dipole interactions and influenced by an external magnetic field. Two coupled equations for the inverse spin temperatures of both the spin systems describing the mutual spin-lattice relaxation and the thermal mixing were obtained using the method of the nonequilibrium state operator. It is shown that the relaxation process is realized with non-exponential time dependence described by a sum of two exponents. The calculated relaxation time versus the multiple-pulse field parameters agrees well with the obtained experimental data in 1,4-dichloro-2-nitrobenzene. The calculated magnetization relaxation time versus the strength of the applied magnetic field agrees well with the obtained experimental data

  2. Analysis of ringing effects due to magnetic core materials in pulsed nuclear magnetic resonance circuits

    Energy Technology Data Exchange (ETDEWEB)

    Prabhu Gaunkar, N., E-mail: neelampg@iastate.edu; Bouda, N. R. Y.; Nlebedim, I. C.; Hadimani, R. L.; Mina, M.; Jiles, D. C. [Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011 (United States); Bulu, I.; Ganesan, K.; Song, Y. Q. [Schlumberger-Doll Research, Cambridge, Massachusetts 02139 (United States)

    2015-05-07

    This work presents investigations and detailed analysis of ringing in a non-resonant pulsed nuclear magnetic resonance (NMR) circuit. Ringing is a commonly observed phenomenon in high power switching circuits. The oscillations described as ringing impede measurements in pulsed NMR systems. It is therefore desirable that those oscillations decay fast. It is often assumed that one of the causes behind ringing is the role of the magnetic core used in the antenna (acting as an inductive load). We will demonstrate that an LRC subcircuit is also set-up due to the inductive load and needs to be considered due to its parasitic effects. It is observed that the parasitics associated with the inductive load become important at certain frequencies. The output response can be related to the response of an under-damped circuit and to the magnetic core material. This research work demonstrates and discusses ways of controlling ringing by considering interrelationships between different contributing factors.

  3. Nanosecond pulsed electric field induced cytoskeleton, nuclear membrane and telomere damage adversely impact cell survival.

    Science.gov (United States)

    Stacey, M; Fox, P; Buescher, S; Kolb, J

    2011-10-01

    We investigated the effects of nanosecond pulsed electric fields (nsPEF) on three human cell lines and demonstrated cell shrinkage, breakdown of the cytoskeleton, nuclear membrane and chromosomal telomere damage. There was a differential response between cell types coinciding with cell survival. Jurkat cells showed cytoskeleton, nuclear membrane and telomere damage that severely impacted cell survival compared to two adherent cell lines. Interestingly, disruption of the actin cytoskeleton in adherent cells prior to nsPEF exposure significantly reduced cell survival. We conclude that nsPEF applications are able to induce damage to the cytoskeleton and nuclear membrane. Telomere sequences, regions that tether and stabilize DNA to the nuclear membrane, are severely compromised as measured by a pan-telomere probe. Internal pore formation following nsPEF applications has been described as a factor in induced cell death. Here we suggest that nsPEF induced physical changes to the cell in addition to pore formation need to be considered as an alternative method of cell death. We suggest nsPEF electrochemical induced depolymerization of actin filaments may account for cytoskeleton and nuclear membrane anomalies leading to sensitization. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. System for determining the type of nuclear radiation from detector output pulse shape

    Science.gov (United States)

    Miller, William H.; Berliner, Ronald R.

    1994-01-01

    A radiation detection system determines the type of nuclear radiation received in a detector by producing a correlation value representative of the statistical cross correlation between the shape of the detector signal and pulse shape data previously stored in memory and characteristic of respective types of radiation. The correlation value is indicative of the type of radiation. The energy of the radiation is determined from the detector signal and is used to produce a spectrum of radiation energies according to radiation type for indicating the nature of the material producing the radiation.

  5. Application of CPML to two-dimension numerical simulation of nuclear electromagnetic pulse from air explosions

    International Nuclear Information System (INIS)

    Gao Chunxia; Wang Lianghou

    2005-01-01

    The characteristics of different types of PML were analyzed and the convolutional PML was chosen to truncate the open boundaries in numerical simulation of nuclear electromagnetic pulse from air explosions. On the basis of the split-field PML and the plane-wave solution of electromagnetic field in free space, the unsplit-field PML was constructed. By applying the convolutional theorem of Fourier transform, the discrete iterative equations of electromagnetic field components were presented in the CPML media under the two-dimension prolate-spheroidal coordinate system. The numerical results indicate that the method of CPML can largely decrease calculation errors of boundary fields. (authors)

  6. Flight test techniques for validating simulated nuclear electromagnetic pulse aircraft responses

    Science.gov (United States)

    Winebarger, R. M.; Neely, W. R., Jr.

    1984-01-01

    An attempt has been made to determine the effects of nuclear EM pulses (NEMPs) on aircraft systems, using a highly instrumented NASA F-106B to document the simulated NEMP environment at the Kirtland Air Force Base's Vertically Polarized Dipole test facility. Several test positions were selected so that aircraft orientation relative to the test facility would be the same in flight as when on the stationary dielectric stand, in order to validate the dielectric stand's use in flight configuration simulations. Attention is given to the flight test portions of the documentation program.

  7. FPGA-based technology for Pulse Height Analysis in nuclear spectrometry system

    International Nuclear Information System (INIS)

    Andrianiaina, H.; Raoelina Andriambololona; Rajaobelison, J.; Rambolamanana, G.; Roengen, H.

    2009-01-01

    Facing the rapid technology development applied in nuclear instruments, Madagascar-INSTN has taken measures to estabilish and enhance the national capabilities in their maintenance, calibration, design/modification and repair, which is a key factor in the development of sustainable nuclear technology.The maintenance will be more convenient if all technical resources are made available: this is only possible when the acces to designer side of the instruments is permitted. Research and instrumentation development projects have been developed to support and to fit the local needs: Pulse Height Analysis algorithm is designed within FPGA and VHDL programming technics to build a Multi-Input Multi-Channel Analyzer. Description and measurement results with the MIMCA will be described in the present paper

  8. Propulsion Systems

    Science.gov (United States)

    2011-03-31

    glycerin, liquid metals, and various ionic liquids ( molten salts ). It is possible to operate these devices in a bipolar mode where the ion accelerator... uranium . In solar propulsion, energy from the sun is collected and used to produce thrust. Some designs use solar energy directly to heat a...Start Validation Testing,” paper no. AIAA-2001-3261 presented at the 37th AIAA/ASME/SAE/ASEE Joint Propulsion Conference. Salt Lake City, UT, July 8-11

  9. Propulsion Research at the Propulsion Research Center of the NASA Marshall Space Flight Center

    Science.gov (United States)

    Blevins, John; Rodgers, Stephen

    2003-01-01

    The Propulsion Research Center of the NASA Marshall Space Flight Center is engaged in research activities aimed at providing the bases for fundamental advancement of a range of space propulsion technologies. There are four broad research themes. Advanced chemical propulsion studies focus on the detailed chemistry and transport processes for high-pressure combustion, and on the understanding and control of combustion stability. New high-energy propellant research ranges from theoretical prediction of new propellant properties through experimental characterization propellant performance, material interactions, aging properties, and ignition behavior. Another research area involves advanced nuclear electric propulsion with new robust and lightweight materials and with designs for advanced fuels. Nuclear electric propulsion systems are characterized using simulated nuclear systems, where the non-nuclear power source has the form and power input of a nuclear reactor. This permits detailed testing of nuclear propulsion systems in a non-nuclear environment. In-space propulsion research is focused primarily on high power plasma thruster work. New methods for achieving higher thrust in these devices are being studied theoretically and experimentally. Solar thermal propulsion research is also underway for in-space applications. The fourth of these research areas is advanced energetics. Specific research here includes the containment of ion clouds for extended periods. This is aimed at proving the concept of antimatter trapping and storage for use ultimately in propulsion applications. Another activity in this involves research into lightweight magnetic technology for space propulsion applications.

  10. Pulsed Power Science and Technology: A Strategic Outlook for the National Nuclear Security Administration (Summary)

    Energy Technology Data Exchange (ETDEWEB)

    Sinars, Daniel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Scott, Kimberly Carole [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Edwards, M. John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olson, Russell Teall [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-10-17

    Major advances in pulsed power technology and applications over the last twenty years have expanded the mission areas for pulsed power and created compelling new opportunities for the Stockpile Stewardship Program (SSP). This summary document is a forward look at the development of pulsed power science and technology (PPS&T) capabilities in support of the next 20 years of the SSP. This outlook was developed during a three-month-long tri-lab study on the future of PPS&T research and capabilities in support of applications to: (1) Dynamic Materials, (2) Thermonuclear Burn Physics and Inertial Confinement Fusion (ICF), and (3) Radiation Effects and Nuclear Survivability. It also considers necessary associated developments in next-generation codes and pulsed power technology as well as opportunities for academic, industry, and international engagement. The document identifies both imperatives and opportunities to address future SSP mission needs. This study was commissioned by the National Nuclear Security Administration (NNSA). A copy of the memo request is contained in the Appendix. NNSA guidance received during this study explicitly directed that it not be constrained by resource limitations and not attempt to prioritize its findings against plans and priorities in other areas of the national weapons program. That prioritization, including the relative balance amongst the three focus areas themselves, must of course occur before any action is taken on the observations presented herein. This unclassified summary document presents the principal imperatives and opportunities identified in each mission and supporting area during this study. Preceding this area-specific outlook, we discuss a cross-cutting opportunity to increase the shot capacity on the Z pulsed power facility as a near-term, cost-effective way to broadly impact PPS&T for SSP as well as advancing the science and technology to inform future SSMP milestones over the next 5-10 years. The final page of the

  11. Pulsed Power Science and Technology: A Strategic Outlook for the National Nuclear Security Administration (Summary)

    International Nuclear Information System (INIS)

    Sinars, Daniel; Scott, Kimberly Carole; Edwards, M. John; Olson, Russell Teall

    2016-01-01

    Major advances in pulsed power technology and applications over the last twenty years have expanded the mission areas for pulsed power and created compelling new opportunities for the Stockpile Stewardship Program (SSP). This summary document is a forward look at the development of pulsed power science and technology (PPS&T) capabilities in support of the next 20 years of the SSP. This outlook was developed during a three-month-long tri-lab study on the future of PPS&T research and capabilities in support of applications to: (1) Dynamic Materials, (2) Thermonuclear Burn Physics and Inertial Confinement Fusion (ICF), and (3) Radiation Effects and Nuclear Survivability. It also considers necessary associated developments in next-generation codes and pulsed power technology as well as opportunities for academic, industry, and international engagement. The document identifies both imperatives and opportunities to address future SSP mission needs. This study was commissioned by the National Nuclear Security Administration (NNSA). A copy of the memo request is contained in the Appendix. NNSA guidance received during this study explicitly directed that it not be constrained by resource limitations and not attempt to prioritize its findings against plans and priorities in other areas of the national weapons program. That prioritization, including the relative balance amongst the three focus areas themselves, must of course occur before any action is taken on the observations presented herein. This unclassified summary document presents the principal imperatives and opportunities identified in each mission and supporting area during this study. Preceding this area-specific outlook, we discuss a cross-cutting opportunity to increase the shot capacity on the Z pulsed power facility as a near-term, cost-effective way to broadly impact PPS&T for SSP as well as advancing the science and technology to inform future SSMP milestones over the next 5-10 years. The final page of the

  12. Frequency-agile gyrotron for electron decoupling and pulsed dynamic nuclear polarization.

    Science.gov (United States)

    Scott, Faith J; Saliba, Edward P; Albert, Brice J; Alaniva, Nicholas; Sesti, Erika L; Gao, Chukun; Golota, Natalie C; Choi, Eric J; Jagtap, Anil P; Wittmann, Johannes J; Eckardt, Michael; Harneit, Wolfgang; Corzilius, Björn; Th Sigurdsson, Snorri; Barnes, Alexander B

    2018-04-01

    We describe a frequency-agile gyrotron which can generate frequency-chirped microwave pulses. An arbitrary waveform generator (AWG) within the NMR spectrometer controls the microwave frequency, enabling synchronized pulsed control of both electron and nuclear spins. We demonstrate that the acceleration of emitted electrons, and thus the microwave frequency, can be quickly changed by varying the anode voltage. This strategy results in much faster frequency response than can be achieved by changing the potential of the electron emitter, and does not require a custom triode electron gun. The gyrotron frequency can be swept with a rate of 20 MHz/μs over a 670 MHz bandwidth in a static magnetic field. We have already implemented time-domain electron decoupling with dynamic nuclear polarization (DNP) magic angle spinning (MAS) with this device. In this contribution, we show frequency-swept DNP enhancement profiles recorded without changing the NMR magnet or probe. The profile of endofullerenes exhibits a DNP profile with a agile high-power microwave sources. Copyright © 2018. Published by Elsevier Inc.

  13. Improvement of pulsing operation performance in the Nuclear Safety Research Reactor (NSRR)

    International Nuclear Information System (INIS)

    Kobayasi, S.; Ishijima, K.; Tanzawa, S.; Fujishiro, T.; Horiki, O.

    1990-01-01

    The Nuclear Safety Research Reactor (NSRR) is one of the TRIGA-type research reactors widely used in the world, and has mainly been used for studying reactor fuel behaviour during postulated reactivity-initiated accidents (RIAs). Its limited pulsing operation capability, however, could produce only a power burst from low power level simulating an RIA event from essentially zero power level. A computerized automatic reactor control system was developed and installed in the NSRR to simulate a wide range of abnormal events in nuclear power plants. This digitalized reactor control system requires no manipulation of the control rods by reactor operators during the course of the pulsing operation. Using this fully automated operation system, a variety of power transients such as power ramping, power bursts from high power level, and so on were made possible with excellent stability and safety. The present modification work in the NSRR and its fruitful results indicate new possibilities in the utilization of the TRIGA type research reactor

  14. Dynamical suppression of nuclear-spin decoherence time in Si and GaAs using inversion pulses

    International Nuclear Information System (INIS)

    Watanabe, S.; Harada, J.; Sasaki, S.; Hirayama, Y.

    2007-01-01

    We found that nuclear-spin decoherence is suppressed by applying inversion pulses such as alternating phase Carr-Purcell (APCP) and Carr-Purcell-Meiboom-Gill (CPMG) sequences in silicon and GaAs. The decoherence time reaches ∼1.3s by applying inversion pulses, which is ∼200 times as long as the characteristic decay time obtained from the Hahn echo sequence (∼6ms) in silicon

  15. A new electron linac for pulse radiolysis experiments at the Institute of Nuclear Chemistry and Technology, Poland

    International Nuclear Information System (INIS)

    Zimek, Z.

    1990-01-01

    A new electron accelerator LAE 10 is under construction at the Institute of Nuclear Chemistry and Technology in Warsaw. This facility will be dedicated to pulse radiolysis and related experiments. The basic parameters of the linac are the following: electron energy 10 MeV, pulse durations 10-100 ns, peak current 10-2 A respectively. Accelerator structure traveling wave type powered by klystron operated at a frequency 1818 MHz is applied. (author)

  16. A new electron linac for pulse radiolysis experiments at the Institute of Nuclear Chemistry and Technology, Poland

    Science.gov (United States)

    Zimek, Z.

    A new electron accelerator LAE 10 is under construction at the Institute of Nuclear Chemistry and Technology in Warsaw. This facility will be dedicated to pulse radiolysis and related experiments. The basic parameters of the linac are the following: electron energy 10 MeV, pulse durations 10-100 ns, peak current 10-2 A respectively. Accelerator structure traveling wave type powered by klystron operated at a frequency 1818 MHz is applied.

  17. Development of Design Information Template for Nuclear Power Plants for Electromagnetic Pulse (EMP) Effect Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Minyi; Ryu, Hosan; Ye, Songhae; Lee, Euijong [KNHP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    An electromagnetic pulse (EMP) is a transient electromagnetic shock wave that has powerful electric and magnetic fields that can destroy electronic equipment. It is generally well-known that EMPs can cause the malfunction and disorder of electronic equipment and serious damages to electric power systems and communication networks. Research is being carried out to protect nuclear power plants (NPPs) from EMP threats. Penetration routes of EMPs can be roughly categorized into two groups, radioactivity and conductivity. The radioactive effect refers to an impact transmitted to the ground from high-altitude electromagnetic pulses (HEMP). Such an impact may affect target equipment through the point of entry (POE) of the concrete structure of an NPP. The conductive effect refers to induced voltage or current coupled to the NPPs cable structure. The induced voltage and current affect the target equipment via connected cables. All these factors must be considered when taking into account EMP effect analysis for NPPs. To examine all factors, it is necessary to fully understand the schemes of NPPs. This paper presents a four type design information template that can be used to analyze the EMP effect in operating nuclear power plants. In order to analyze of the effects of EMPs on operating NPPs, we must consider both the conductive and radioactive effects on the target (system, equipment, structure). For these reasons, not only the equipment information, but also the information about the structure and the external penetration will be required. We are developing a design information template for robust nuclear design information acquisition. We expect to develop a block diagram on the basis of the template.

  18. Basic Research in Electric Propulsion. Part I: Pulsed Plasma Thruster Propellant Efficiency and Contamination. Part II: Arcjet Remote Plume Measurement and Hydrogen Density

    Science.gov (United States)

    2002-02-01

    equipment, ground observatories, and other space platforms. Low power arcjet technology provided definitive work on atomic species plume concentrations...in low power hydrogen arcjet plumes. This work applied a flame diagnostic, Multiphoton Laser Induced Fluorescence, to the excited-state plasma... Low power arcjet technology has been the primary focus of the Air Force Office of Scientific Research’s electric propulsion research program for

  19. Construction of pulse badge for upper extremities dosimetry in nuclear medicine

    International Nuclear Information System (INIS)

    Cunha, Cledison de Jesus; Souza, Divanizia do Nascimento

    2005-01-01

    In the manipulation of radioactive materials in nuclear medicine service the body parts of the worker who more is displayed to the ionizing radiation is hands, forearm and arm. Therefore it is necessary to developing badges for easy reproduction monitoring and low cost to determine the doses level radiation received by the worker in these extremities. The aim of this work is to investigation of a new pulse badge, that is developed with thermoluminescent detectors of CaSO 4 :Dy (TLD) in a small plate of acrylic, perforated cardboard to deposit the TLD. This set was involved in plastic to protect of humidity and other harmful ambient factors, moreover, a bracelet was inserted, adaptable for any worker. This badge had been gotten resulted satisfactory, with a reply to the enough dose for a dosimetric evaluation. (author)

  20. Description of an aircraft lightning and simulated nuclear electromagnetic pulse (NEMP) threat based on experimental data

    Science.gov (United States)

    Rustan, Pedro L., Jr.

    1987-01-01

    Lightning data obtained by measuring the surface electromagnetic fields on a CV-580 research aircraft during 48 lightning strikes between 1500 and 18,000 feet in central Florida during the summers of 1984 and 1985, and nuclear electromagnetic pulse (NEMP) data obtained by surface electromagnetic field measurements using a 1:74 CV-580 scale model, are presented. From one lightning event, maximum values of 3750 T/s for the time rate of change of the surface magnetic flux density, and 4.7 kA for the peak current, were obtained. From the simulated NEMP test, maximum values of 40,000 T/s for the time rate of change of the surface magnetic flux density, and 90 A/sq m for the total normal current density, were found. The data have application to the development of a military aircraft lightning/NEMP standard.

  1. A comparison of lightning and nuclear electromagnetic pulse response of tactical shelters

    Science.gov (United States)

    Perala, R. A.; Rudolph, T. H.; Mckenna, P. M.

    1984-01-01

    The internal response (electromagnetic fields and cable responses) of tactical shelters is addressed. Tactical shelters are usually well-shielded systems. Apart from penetrations by signal and power lines, the main leakage paths to the interior are via seams and the environment control unit (ECU) honeycomb filter. The time domain in three-dimensional finite-difference technique is employed to determine the external and internal coupling to a shelter excited by nuclear electromagnetic pulses (NEMP) and attached lightning. The responses of interest are the internal electromagnetic fields and the voltage, current, power, and energy coupled to internal cables. Leakage through the seams and ECU filter is accomplished by their transfer impedances which relate internal electric fields to external current densities. Transfer impedances which were experimentally measured are used in the analysis. The internal numerical results are favorably compared to actual shelter test data under simulated NEMP illumination.

  2. A comparison of lightning and nuclear electromagnetic pulse response of a helicopter

    Science.gov (United States)

    Easterbrook, C. C.; Perala, R. A.

    1984-01-01

    A numerical modeling technique is utilized to investigate the response of a UH-60A helicopter to both lightning and nuclear electromagnetic pulses (NEMP). The analytical approach involves the three-dimensional time domain finite-difference solutions of Maxwell's equations. Both the external currents and charges as well as the internal electromagnetic fields and cable responses are computed. Results of the analysis indicate that, in general, the short circuit current on internal cables is larger for lightning, whereas the open-circuit voltages are slightly higher for NEMP. The lightning response is highly dependent upon the rise time of the injected current as was expected. The analysis shows that a coupling levels to cables in a helicopter are 20 to 30 dB larger than those observed in fixed-wing aircraft.

  3. Determination of large subcriticality by pulsed neutron method for nuclear criticality safety study

    International Nuclear Information System (INIS)

    Yamane, Y.; Maki, T.; Yoshida, A.; Nishina, K.; Kobayashi, K.

    1986-01-01

    To establish the method determining large subcriticalities in the field of nuclear criticality safety, the authors performed pulsed neutron experiments using the Kyoto University Critical Assembly (KUCA) and a Cockcroft-Walton type accelerator attached to the assembly. In order to remove a contamination of spatial higher modes from the neutron decay curve, which becomes significant as subcriticality increases, the integral-version of the area-ratio method proposed by Kosaly and fisher was employed to evaluate large subcriticalities. This method has the shortcoming that the delayed neutron component remarkably decreases as the subcriticality of a system increases. To experimentally overcome the shortcoming, the frequency of pulsed neutron generation was increased up to 240 Hz. The largest subcriticality determined in the present experiments was 73.41 +/- 1.04 dollars, which was equal to 0.6229 +/- 0.0033 in effective multiplication factor k-eff. The theoretical k-eff, on the other hand, was calculated with the Monte-Carlo code KENO-IV with 137 energy groups. The calculational values were slightly smaller than the experimental values. The discrepancy between the experiment and the calculation was approximately 9% at largest, which was for the smallest measured k-eff

  4. High-speed nuclear quality pulse height analyzer for synchrotron-based applications

    International Nuclear Information System (INIS)

    Beche, Jean-Francois; Bucher, Jerome J.; Fabris, Lorenzo; Riot, Vincent J.

    2001-01-01

    A high throughput Pulse Height Analyzer system for synchrotron-based applications requiring high resolution, high processing speed and low dead time has been developed. The system is comprised of a 120ns 12-bit nuclear quality Analog to Digital converter with a self-adaptive fast peak detector-stretcher and a custom-made fast histogramming memory module that records and processes the digitized data. The histogramming module is packaged in a VME or VXI compatible interface. Data is transferred through a fast optical link from the memory interface to a computer. A dedicated data acquisition program matches the hardware characteristics of the histogramming memory module. The data acquisition system allows for two data collection modes: ''standard'' data acquisition mode where the data is accumulated and read in synchronization with an external trigger and ''live'' data acquisition mode where the system operates as a standard Pulse Height Analyzer. The acquisition, standard or live, can be performed on several channels simultaneously. A two-channel prototype has been demonstrated at the Stanford Synchrotron Radiation Laboratory accelerator in conjunction with an X-ray Fluorescence Absorption Spectroscopy experiment. A detailed description of the entire system is given and experimental data is shown

  5. Study of time-domain digital pulse shaping algorithms for nuclear signals

    International Nuclear Information System (INIS)

    Zhou Jianbin; Tuo Xianguo; Zhu Xing; Liu Yi; Zhou Wei; Lei Jiarong

    2012-01-01

    With the development on high-speed integrated circuit, fast high resolution sampling ADC and digital signal processors are replacing analog shaping amplifier circuit. This paper firstly presents the numerical analysis and simulation on R-C shaping circuit model and C-R shaping circuit model. Mathematic models are established based on 1 st order digital differential method and Kirchhoff Current Law in time domain, and a simulation and error evaluation experiment on an ideal digital signal are carried out with Excel VBA. A digital shaping test for a semiconductor X-ray detector in real time is also presented. Then a numerical analysis for Sallen-Key(S-K) low-pass filter circuit model is implemented based on the analysis of digital R-C and digital C-R shaping methods. By applying the 2 nd order non-homogeneous differential equation,the authors implement a digital Gaussian filter model for a standard exponential-decaying signal and a nuclear pulse signal. Finally, computer simulations and experimental tests are carried out and the results show the possibility of the digital pulse processing algorithms. (authors)

  6. Window of cold nuclear fusion and biased-pulse electrolysis experiment

    International Nuclear Information System (INIS)

    Takahashi, Akito; Jida, Toshiyuki; Maekawa, Fujio; Sugimoto, Hisashi; Yoshida, Shigeo

    1989-01-01

    Based on the electron screening effect and the excitation of deuteron harmonic oscillators in palladium lattice, theoretical aspects are given to explain the cold fusion phenomena and the possibility of nuclear heating. A narrow window is proposed to meet ≅ 10 watts per cubic centimeter for the nuclear heating, by the hypothetical excitation-screening model. A relatively wide window is feasible to meet a few fusion events per second per cc under the non-stationary conditions of deuteron-charging and discharging. For stationary lattice conditions, the probability of cold fusion is not feasible at all. To confirm the cold fusion phenomena, a heavy water electrolysis experiment was carried out using biased-pulse-electrolytic currents, expecting the enhancement of cold fusion events under charging and discharging of deuterons. For the neutron detection, a cross-checking system between a recoil-proton scintillation detector and a 3 He thermal neutron detector was employed to see coincident time-patterns of neutron emission from an electrolysis cell. To check the energy of emitted neutrons, pulse height spectrum of the recoil-proton detector was monitored. Up to the D-charging time of 300 hr, neutron yields of 1-2 n/s/cc were obtained for time-intervals of 60-200 hr. From the recoil-proton spectra, it was confirmed that 2.45 MeV neutrons by the D(d, n) 3 He fusion branch were emitted. The observed time-patterns of neutron emission suggest the existence of cold fusion under the charging and discharging conditions. (orig.)

  7. Pulsed TIG welding in the fabrication of nuclear components and structures

    International Nuclear Information System (INIS)

    Lucas, W.; Males, B.O.

    1979-01-01

    TIG welding is an important welding technique in nuclear plant fabrication for the welding of critical components and structures where a high level of weld integrity is demanded. Whilst the process is ideally suited to precision welding, since the arc is a small intense heat source, it has proved to be somewhat intolerant to production variations in 'difficult' applications, such as tube to tube plate welding and orbital tube welding with tube in the fixed position. Whilst the problems directly associated with this intolerance (of the welding process) are less frequently observed when used manually, difficulties are experienced in fully mechanised welding operations particularly when welding to a relatively rigid approved procedure. Pulsing of the welding current was developed as a technique to achieve greater control of the behaviour of the weld pool. Instead of moving the weld pool in a continuous motion around the joint, welding was conducted intermittently in the form of overlapping spots. This technique, which offers significant advantages over continuous current welding has been exploited in nuclear fabrication for welding those components which demand a high level of weld quality. In this paper, the essential features of this technique are described and, in indicating its advantages, examples have been drawn from recent experiences on the welding of two types of joint for the Advanced Gas Cooled Reactor, a tube sheet and a butt joint in the G Position. (author)

  8. Electric propulsion for small satellites

    Science.gov (United States)

    Keidar, Michael; Zhuang, Taisen; Shashurin, Alexey; Teel, George; Chiu, Dereck; Lukas, Joseph; Haque, Samudra; Brieda, Lubos

    2015-01-01

    Propulsion is required for satellite motion in outer space. The displacement of a satellite in space, orbit transfer and its attitude control are the task of space propulsion, which is carried out by rocket engines. Electric propulsion uses electric energy to energize or accelerate the propellant. The electric propulsion, which uses electrical energy to accelerate propellant in the form of plasma, is known as plasma propulsion. Plasma propulsion utilizes the electric energy to first, ionize the propellant and then, deliver energy to the resulting plasma leading to plasma acceleration. Many types of plasma thrusters have been developed over last 50 years. The variety of these devices can be divided into three main categories dependent on the mechanism of acceleration: (i) electrothermal, (ii) electrostatic and (iii) electromagnetic. Recent trends in space exploration associate with the paradigm shift towards small and efficient satellites, or micro- and nano-satellites. A particular example of microthruster considered in this paper is the micro-cathode arc thruster (µCAT). The µCAT is based on vacuum arc discharge. Thrust is produced when the arc discharge erodes some of the cathode at high velocity and is accelerated out the nozzle by a Lorentz force. The thrust amount is controlled by varying the frequency of pulses with demonstrated range to date of 1-50 Hz producing thrust ranging from 1 µN to 0.05 mN.

  9. Pulsed Lorentz Accelerator

    Data.gov (United States)

    National Aeronautics and Space Administration — The Pulsed Lorentz Accelerator (PLA) is proposed to fill the propulsion gap for 6U and smaller satellites. The primary objective is to demonstrate the basic...

  10. A numerical simulation package for analysis of neutronics and thermal fluids of space nuclear power and propulsion systems

    International Nuclear Information System (INIS)

    Anghaie, S.; Feller, G.J.; Peery, S.D.; Parsley, R.C.

    1993-01-01

    A system of computer codes for engineering simulation and in-depth analysis of nuclear and thermal fluid design of nuclear thermal rockets is developed. The computational system includes a neutronic solver package, a thermal fluid solver package and a propellant and materials property package. The Rocket Engine Transient Simulation (ROCETS) system code is incorporated with computational modules specific to nuclear powered engines. ROCETS features a component based performance architecture that interfaces component modules into the user designed configuration, interprets user commands, creates an executable FORTRAN computer program, and executes the program to provide output to the user. Basic design features of the Pratt ampersand Whitney XNR2000 nuclear rocket concept and its operational performance are analyzed and simulated

  11. Propulsion materials

    Energy Technology Data Exchange (ETDEWEB)

    Wall, Edward J. [U.S. Dept. of Energy, Washington, D.C. (United States); Sullivan, Rogelio A. [U.S. Dept. of Energy, Washington, D.C. (United States); Gibbs, Jerry L. [U.S. Dept. of Energy, Washington, D.C. (United States)

    2008-01-01

    The Department of Energy’s (DOE’s) Office of Vehicle Technologies (OVT) is pleased to introduce the FY 2007 Annual Progress Report for the Propulsion Materials Research and Development Program. Together with DOE national laboratories and in partnership with private industry and universities across the United States, the program continues to engage in research and development (R&D) that provides enabling materials technology for fuel-efficient and environmentally friendly commercial and passenger vehicles.

  12. Detailed Characterization of Nuclear Recoil Pulse Shape Discrimination in the Darkside-50 Direct Dark Matter Experiment

    Science.gov (United States)

    Ludert, Erin Edkins

    While evidence of non-baryonic dark matter has been accumulating for decades, its exact nature continues to remain a mystery. Weakly Interacting Massive Particles (WIMPs) are a well motivated candidate which appear in certain extensions of the Standard Model, independently of dark matter theory. If such particles exist, they should occasionally interact with particles of normal matter, producing a signal which may be detected. The DarkSide-50 direct dark matter experiment aims to detect the energy of recoiling argon atoms due to the elastic scattering of postulated WIMPs. In order to make such a discovery, a clear understanding of both the background and signal region is essential. This understanding requires a careful study of the detector's response to radioactive sources, which in turn requires such sources may be safely introduced into or near the detector volume and reliably removed. The CALibration Insertaion System (CALIS) was designed and built for this purpose in a joint effort between Fermi National Laboratory and the University of Hawaii. This work describes the design and testing of CALIS, its installation and commissioning at the Laboratori Nazionali del Gran Sasso (LNGS) and the multiple calibration campaigns which have successfully employed it. As nuclear recoils produced by WIMPs are indistinguishable from those produced by neutrons, radiogenic neutrons are both the most dangerous class of background and a vital calibration source for the study of the potential WIMP signal. Prior to the calibration of DarkSide-50 with radioactive neutron sources, the acceptance region was determined by the extrapolation of nuclear recoil data from a separate, dedicated experiment, ScENE, which measured the distribution of the pulse shape discrimination parameter, f 90, for nuclear recoils of known energies. This work demonstrates the validity of the extrapolation of ScENE values to DarkSide-50, by direct comparison of the f90 distribution of nuclear recoils from Sc

  13. Boundary effects of molecular diffusion in nanoporous materials: A pulsed field gradient nuclear magnetic resonance study

    Science.gov (United States)

    Geier, Oliver; Snurr, Randall Q.; Stallmach, Frank; Kärger, Jörg

    2004-01-01

    The boundary conditions of intraparticle diffusion in nanoporous materials may be chosen to approach the limiting cases of either absorbing or reflecting boundaries, depending on the host-guest system under study and the temperature of measurement. Pulsed field gradient nuclear magnetic resonance is applied to monitor molecular diffusion of n-hexane and of an n-hexane-tetrafluoromethane mixture adsorbed in zeolite crystallites of type NaX under either of these limiting conditions. Taking advantage of the thus-established peculiarities of mass transfer at the interface between the zeolite bulk phase and the surrounding atmosphere, three independent routes for probing the crystal size are compared. These techniques are based on (i) the measurement of the effective diffusivity under complete confinement, (ii) the application of the so-called NMR tracer desorption technique, and (iii) an analysis of the time dependence of the effective diffusivity in the short-time limit where, by an appropriate variation of the adsorbate and the measuring conditions, the limiting cases of reflecting and adsorbing boundaries could be considered. All these techniques are found to yield coinciding results, which are in excellent agreement with the crystal sizes determined by microscopy.

  14. Effects of nuclear electromagnetic pulse (EMP) on synchronous stability of the electric power system

    International Nuclear Information System (INIS)

    Manweiler, R.W.

    1975-11-01

    The effects of a nuclear electromagnetic pulse (EMP) on the synchronous stability of the electric power transmission and distribution systems are evaluated. The various modes of coupling of EMP to the power system are briefly discussed, with particular emphasis on those perturbations affecting the synchronous stability of the transmission system. A brief review of the fundamental concepts of the stability problem is given, with a discussion of the general characteristics of transient analysis. A model is developed to represent single sets as well as repetitive sets of multiple faults on the distribution systems, as might be produced by EMP. The results of many numerical stability calculations are presented to illustrate the transmission system's response from different types of perturbations. The important parameters of both multiple and repetitive faults are studied, including the dependence of the response on the size of the perturbed area, the fault density, and the effective impedance between the fault location and the transmission system. Both major load reduction and the effect of the opening of tie lines at the time of perturbation are also studied. We conclude that there is a high probability that EMP can induce perturbations on the distribution networks causing a large portion of the transmission network in the perturbed area to lose synchronism. The result would be an immediate and massive power failure

  15. Integral-equation based methods for parameter estimation in output pulses of radiation detectors: Application in nuclear medicine and spectroscopy

    Science.gov (United States)

    Mohammadian-Behbahani, Mohammad-Reza; Saramad, Shahyar

    2018-04-01

    Model based analysis methods are relatively new approaches for processing the output data of radiation detectors in nuclear medicine imaging and spectroscopy. A class of such methods requires fast algorithms for fitting pulse models to experimental data. In order to apply integral-equation based methods for processing the preamplifier output pulses, this article proposes a fast and simple method for estimating the parameters of the well-known bi-exponential pulse model by solving an integral equation. The proposed method needs samples from only three points of the recorded pulse as well as its first and second order integrals. After optimizing the sampling points, the estimation results were calculated and compared with two traditional integration-based methods. Different noise levels (signal-to-noise ratios from 10 to 3000) were simulated for testing the functionality of the proposed method, then it was applied to a set of experimental pulses. Finally, the effect of quantization noise was assessed by studying different sampling rates. Promising results by the proposed method endorse it for future real-time applications.

  16. The high-density Z-pinch as a pulsed fusion neutron source for fusion nuclear technology and materials testing

    International Nuclear Information System (INIS)

    Krakowski, R.A.; Sethian, J.D.; Hagenson, R.L.

    1989-01-01

    The dense Z-pinch (DZP) is one of the earliest and simplest plasma heating and confinement schemes. Recent experimental advances based on plasma initiation from hair-like (10s μm in radius) solid hydrogen filaments have so far not encountered the usually devastating MHD instabilities that plagued early DZP experiments. These encouraging results along with debt of a number of proof-of principle, high-current (1--2 MA in 10--100 ns) experiments have prompted consideration of the DZP as a pulsed source of DT fusion neutrons of sufficient strength (/dot S//sub N/ ≥ 10 19 n/s) to provide uncollided neutron fluxes in excess of I/sub ω/ = 5--10 MW/m 2 over test volumes of 10--30 litre or greater. While this neutron source would be pulsed (100s ns pulse widths, 10--100 Hz pulse rate), giving flux time compressions in the range 10 5 --10 6 , its simplicity, near-time feasibility, low cost, high-Q operation, and relevance to fusion systems that may provide a pulsed commercial end-product (e.g., inertial confinement or the DZP itself) together create the impetus for preliminary considerations as a neutron source for fusion nuclear technology and materials testings. The results of a preliminary parametric systems study (focusing primarily on physics issues), conceptual design, and cost versus performance analyses are presented. The DZP promises an expensive and efficient means to provide pulsed DT neutrons at an average rate in excess of 10 19 n/s, with neutron currents I/sub ω/ /approx lt/ 10 MW/m 2 over volumes V/sub exp/ ≥ 30 litre using single-pulse technologies that differ little from those being used in present-day experiments. 34 refs., 17 figs., 6 tabs

  17. Random pulse generator

    International Nuclear Information System (INIS)

    Guo Ya'nan; Jin Dapeng; Zhao Dixin; Liu Zhen'an; Qiao Qiao; Chinese Academy of Sciences, Beijing

    2007-01-01

    Due to the randomness of radioactive decay and nuclear reaction, the signals from detectors are random in time. But normal pulse generator generates periodical pulses. To measure the performances of nuclear electronic devices under random inputs, a random generator is necessary. Types of random pulse generator are reviewed, 2 digital random pulse generators are introduced. (authors)

  18. A Multi-Dimensional Heat Transfer Model of a Tie-Tube and Hexagonal Fuel Element for Nuclear Thermal Propulsion

    Science.gov (United States)

    Gomez, C. F.; Mireles, O. R.; Stewart, E.

    2016-01-01

    The Space Capable Cryogenic Thermal Engine (SCCTE) effort considers a nuclear thermal rocket design based around a Low-Enriched Uranium (LEU) design fission reactor. The reactor core is comprised of bundled hexagonal fuel elements that directly heat hydrogen for expansion in a thrust chamber and hexagonal tie-tubes that house zirconium hydride moderator mass for the purpose of thermalizing fast neutrons resulting from fission events. Created 3D steady state Hex fuel rod model with 1D flow channels. Hand Calculation were used to set up initial conditions for fluid flow. The Hex Fuel rod uses 1D flow paths to model the channels using empirical correlations for heat transfer in a pipe. Created a 2-D axisymmetric transient to steady state model using the CFD turbulent flow and Heat Transfer module in COMSOL. This model was developed to find and understand the hydrogen flow that might effect the thermal gradients axially and at the end of the tie tube where the flow turns and enters an annulus. The Hex fuel rod and Tie tube models were made based on requirements given to us by CSNR and the SCCTE team. The models helped simplify and understand the physics and assumptions. Using pipe correlations reduced the complexity of the 3-D fuel rod model and is numerically more stable and computationally more time-efficient compared to the CFD approach. The 2-D axisymmetric tie tube model can be used as a reference "Virtual test model" for comparing and improving 3-D Models.

  19. Variable delay multi-pulse train for fast chemical exchange saturation transfer and relayed-nuclear overhauser enhancement MRI.

    Science.gov (United States)

    Xu, Jiadi; Yadav, Nirbhay N; Bar-Shir, Amnon; Jones, Craig K; Chan, Kannie W Y; Zhang, Jiangyang; Walczak, P; McMahon, Michael T; van Zijl, Peter C M

    2014-05-01

    Chemical exchange saturation transfer (CEST) imaging is a new MRI technology allowing the detection of low concentration endogenous cellular proteins and metabolites indirectly through their exchangeable protons. A new technique, variable delay multi-pulse CEST (VDMP-CEST), is proposed to eliminate the need for recording full Z-spectra and performing asymmetry analysis to obtain CEST contrast. The VDMP-CEST scheme involves acquiring images with two (or more) delays between radiofrequency saturation pulses in pulsed CEST, producing a series of CEST images sensitive to the speed of saturation transfer. Subtracting two images or fitting a time series produces CEST and relayed-nuclear Overhauser enhancement CEST maps without effects of direct water saturation and, when using low radiofrequency power, minimal magnetization transfer contrast interference. When applied to several model systems (bovine serum albumin, crosslinked bovine serum albumin, l-glutamic acid) and in vivo on healthy rat brain, VDMP-CEST showed sensitivity to slow to intermediate range magnetization transfer processes (rate < 100-150 Hz), such as amide proton transfer and relayed nuclear Overhauser enhancement-CEST. Images for these contrasts could be acquired in short scan times by using a single radiofrequency frequency. VDMP-CEST provides an approach to detect CEST effect by sensitizing saturation experiments to slower exchange processes without interference of direct water saturation and without need to acquire Z-spectra and perform asymmetry analysis. Copyright © 2013 Wiley Periodicals, Inc.

  20. Optimal temperature of operation of the cold side of a closed Brayton Cycle for space nuclear propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Romano, Luís F.R.; Ribeiro, Guilherme B., E-mail: luisromano_91@hotmail.com, E-mail: gbribeiro@ieav.cta.br [Instituto Tecnológico de Aeronáutica (ITA), São José dos Campos, SP (Brazil). Pós-Graduação Ciências e Tecnologias Espaciais

    2017-07-01

    Generating energy in space is a tough challenge, especially because it has to be used efficiently. The optimization of the system operation has to be though up since the design phase and all the minutiae between conception, production and operation should be carefully evaluated in order to deliver a functioning device that will meet all the mission's goals. This work seeks on further describing the operation of a Closed Brayton Cycle coupled toa nuclear microreactor used to generate energy to power spacecraft's systems, focusing specially on the cold side to evaluate the temperature of operation of the cold heat pipes in order to aid the selection of proper models to numerically describe the heat pipes and radiator s thermal operation. The cycle is designed to operate with a noble gas mixture of Helium-Xenon with a molecular weight of 40g/mole, selected for its transport properties and low turbomachinery charge and it is to exchange hear directly with the cold heat pipe' evaporator through convection at the cold heat exchanger. Properties such as size and mass are relevant to be analyzed due space applications requiring a careful development of the equipment in order to fit inside the launcher as well as lowering launch costs. Merit figures comparing both second law energetic efficiency and net energy availability with the device's radiator size are used in order to represent an energetic production density for the apparatus, which is ought to be launched from earth's surface. (author)

  1. Optimal temperature of operation of the cold side of a closed Brayton Cycle for space nuclear propulsion

    International Nuclear Information System (INIS)

    Romano, Luís F.R.; Ribeiro, Guilherme B.

    2017-01-01

    Generating energy in space is a tough challenge, especially because it has to be used efficiently. The optimization of the system operation has to be though up since the design phase and all the minutiae between conception, production and operation should be carefully evaluated in order to deliver a functioning device that will meet all the mission's goals. This work seeks on further describing the operation of a Closed Brayton Cycle coupled toa nuclear microreactor used to generate energy to power spacecraft's systems, focusing specially on the cold side to evaluate the temperature of operation of the cold heat pipes in order to aid the selection of proper models to numerically describe the heat pipes and radiator s thermal operation. The cycle is designed to operate with a noble gas mixture of Helium-Xenon with a molecular weight of 40g/mole, selected for its transport properties and low turbomachinery charge and it is to exchange hear directly with the cold heat pipe' evaporator through convection at the cold heat exchanger. Properties such as size and mass are relevant to be analyzed due space applications requiring a careful development of the equipment in order to fit inside the launcher as well as lowering launch costs. Merit figures comparing both second law energetic efficiency and net energy availability with the device's radiator size are used in order to represent an energetic production density for the apparatus, which is ought to be launched from earth's surface. (author)

  2. Chemical and Electric Propulsion Options for Small Satellites

    OpenAIRE

    Myers, Roger; Oleson, Steven; Currant, Francis; Schneider, Steven

    1994-01-01

    Advanced chemical and low power electric propulsion systems offer attractive options for near-term small satellite propulsion. Applications include orbit raising, orbit maintenance, attitude control, repositioning, and deorbit of both Earth-space and planetary spacecraft. Potential propulsion technologies for these functions include high pressure Ir/Re bipropellant engines, very low power arcjets, Hall thrusters, and pulsed plasma thrusters, all of which have been shown to operate in manners ...

  3. A high precision peak sensing circuit for measuring the integral linearity of nuclear pulse amplifiers

    International Nuclear Information System (INIS)

    Rogers, L.C.

    1989-01-01

    This paper describes a new instrument that very accurately transforms the peak height of repetitive waveforms into a dc voltage. Used in conjunction with a precision pulse generator, this instrument provides an improved method for establishing the integral linearity of pulse amplifiers. A measured overall accuracy of 0.005% for pulses with a nominal 1.0 μs peaking time has been achieved. This method is particularly useful with very fast amplifiers in the 5-100 ns range. The results of linearity measurements on several typical amplifiers are presented. (orig.)

  4. Decoupling Electronic versus Nuclear Photoresponse of Isolated Green Fluorescent Protein Chromophores Using Short Laser Pulses

    Science.gov (United States)

    Kiefer, Hjalte V.; Pedersen, Henrik B.; Bochenkova, Anastasia V.; Andersen, Lars H.

    2016-12-01

    The photophysics of a deprotonated model chromophore for the green fluorescent protein is studied by femtosecond laser pulses in an electrostatic ion-storage ring. The laser-pulse duration is much shorter than the time for internal conversion, and, hence, contributions from sequential multiphoton absorption, typically encountered with ns-laser pulses, are avoided. Following single-photon excitation, the action-absorption maximum is shown to be shifted within the S0 to S1 band from its origin at about 490 to 450 nm, which is explained by the different photophysics involved in the detected action.

  5. Boron-Proton Nuclear-Fusion Enhancement Induced in Boron-Doped Silicon Targets by Low-Contrast Pulsed Laser

    Directory of Open Access Journals (Sweden)

    A. Picciotto

    2014-08-01

    Full Text Available We show that a spatially well-defined layer of boron dopants in a hydrogen-enriched silicon target allows the production of a high yield of alpha particles of around 10^{9} per steradian using a nanosecond, low-contrast laser pulse with a nominal intensity of approximately 3×10^{16}  W cm^{−2}. This result can be ascribed to the nature of the long laser-pulse interaction with the target and with the expanding plasma, as well as to the optimal target geometry and composition. The possibility of an impact on future applications such as nuclear fusion without production of neutron-induced radioactivity and compact ion accelerators is anticipated.

  6. Nuclear Material Detection by One-Short-Pulse-Laser-Driven Neutron Source

    Energy Technology Data Exchange (ETDEWEB)

    Favalli, Andrea [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Aymond, F. [Univ. of Texas at Austin, TX (United States); Bridgewater, Jon S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Croft, Stephen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Deppert, O. [Technische Universitat Darmstadt (Germany); Devlin, Matthew James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Falk, Katerina [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fernandez, Juan Carlos [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gautier, Donald Cort [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gonzales, Manuel A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Goodsell, Alison Victoria [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Guler, Nevzat [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hamilton, Christopher Eric [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hegelich, Bjorn Manuel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Henzlova, Daniela [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ianakiev, Kiril Dimitrov [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Iliev, Metodi [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Johnson, Randall Philip [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jung, Daniel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kleinschmidt, Annika [Technische Universitat Darmstadt (Germany); Koehler, Katrina Elizabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pomerantz, Ishay [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Roth, Markus [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Santi, Peter Angelo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Shimada, Tsutomu [Los Alamos National Laboratory; Swinhoe, Martyn Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Taddeucci, Terry Nicholas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wurden, Glen Anthony [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Palaniyappan, Sasikumar [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); McCary, E. [Univ. of Texas at Austin, TX (United States)

    2015-01-28

    Covered in the PowerPoint presentation are the following areas: Motivation and requirements for active interrogation of nuclear material; laser-driven neutron source; neutron diagnostics; active interrogation of nuclear material; and, conclusions, remarks, and future works.

  7. NASA Propulsion Engineering Research Center, volume 2

    Science.gov (United States)

    1993-01-01

    On 8-9 Sep. 1993, the Propulsion Engineering Research Center (PERC) at The Pennsylvania State University held its Fifth Annual Symposium. PERC was initiated in 1988 by a grant from the NASA Office of Aeronautics and Space Technology as a part of the University Space Engineering Research Center (USERC) program; the purpose of the USERC program is to replenish and enhance the capabilities of our Nation's engineering community to meet its future space technology needs. The Centers are designed to advance the state-of-the-art in key space-related engineering disciplines and to promote and support engineering education for the next generation of engineers for the national space program and related commercial space endeavors. Research on the following areas was initiated: liquid, solid, and hybrid chemical propulsion, nuclear propulsion, electrical propulsion, and advanced propulsion concepts.

  8. Safe, Compact Nuclear Propulsion: Solid Core Nuclear Propulsion Concept

    Science.gov (United States)

    1988-10-01

    Keactor Test Facility (TREAT), the High Flux Isotope Reactor ( HFIR ), and the Advanced Test Reactor (ATR) were evaluated for their potential in testing...for very brief irradiation periods and for less than failure conditions would probably be possible. 151 The High Flux Isotope Reactor ( HFIR ) was also

  9. Applications of pulsed nuclear magnetic resonance to chemistry: multiple-pulse NMR, cross polarization, magic-angle spinning annd instrumental design

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, P.D.

    1979-07-01

    Pulsed Nuclear Magnetic Resonance (NMR) has been applied to: (1) Measurements of the prinicpal components of the proton shielding tensors of the hydrides of zirconium chloride and zirconium bromide. Multiple-Pulse techniques have been used to remove static homonuclear dipolar coupling. The anisotropies and isotropic shifts of these tensors have been used to infer the possible locations of the hydrogen within the sandwich-like layers of these unusual compounds. (2) Studies of the oscillatory transfer of magnetic polarization between /sup 1/H and /sup 29/Si in substituted silanes. The technique of J Cross Polarization has been used to enhance sensitivity. The /sup 29/Si NMR shifts of -Si-O- model compounds have been investigated as a possible probe for future studies of the environment of bound oxygen in coal-derived liquids. (3) Measurements of the aromatic fraction of /sup 13/C in whole coals. The techniques of /sup 1/H-/sup 13/C Cross Polarization and Magic-Angle Spinning have been used to enhance sensitivity and remove shift anisotropy. Additional topics described are: (4) Calculation and properties of the broadened lineshape of the shileding Powder Pattern. (5) Calculation of the oscillatory transfer of magnetic polarization for an I-S system. (6) Numerical convolution and its uses. (7) The technique of digital filtering applied in the frequency domain. (8) The designs and properties of four NMR probe-circuits. (9) The design of a single-coil double-resonance probe for combined Magic-Angle Spinning and Cross Polarization. (10) The designs of low Q and high Q rf power amplifiers with emphasis on the rf matching circuitry.

  10. Urinary1H Nuclear Magnetic Resonance Metabolomic Fingerprinting Reveals Biomarkers of Pulse Consumption Related to Energy-Metabolism Modulation in a Subcohort from the PREDIMED study.

    Science.gov (United States)

    Madrid-Gambin, Francisco; Llorach, Rafael; Vázquez-Fresno, Rosa; Urpi-Sarda, Mireia; Almanza-Aguilera, Enrique; Garcia-Aloy, Mar; Estruch, Ramon; Corella, Dolores; Andres-Lacueva, Cristina

    2017-04-07

    Little is known about the metabolome fingerprint of pulse consumption. The study of robust and accurate biomarkers for pulse dietary assessment has great value for nutritional epidemiology regarding health benefits and their mechanisms. To characterize the fingerprinting of dietary pulses (chickpeas, lentils, and beans), spot urine samples from a subcohort from the PREDIMED study were stratified using a validated food frequency questionnaire. Urine samples of nonpulse consumers (≤4 g/day of pulse intake) and habitual pulse consumers (≥25 g/day of pulse intake) were analyzed using a 1 H nuclear magnetic resonance (NMR) metabolomics approach combined with multi- and univariate data analysis. Pulse consumption showed differences through 16 metabolites coming from (i) choline metabolism, (ii) protein-related compounds, and (iii) energy metabolism (including lower urinary glucose). Stepwise logistic regression analysis was applied to design a combined model of pulse exposure, which resulted in glutamine, dimethylamine, and 3-methylhistidine. This model was evaluated by a receiver operating characteristic curve (AUC > 90% in both training and validation sets). The application of NMR-based metabolomics to reported pulse exposure highlighted new candidates for biomarkers of pulse consumption and the impact on energy metabolism, generating new hypotheses on energy modulation. Further intervention studies will confirm these findings.

  11. An Improved Nuclear Recoil Calibration in the LUX Detector Using a Pulsed D-D Neutron Generator

    Science.gov (United States)

    Huang, Dongqing

    2017-01-01

    The LUX dark matter search experiment is a 370 kg (250 kg active mass) two-_phase liquid/gas xenon time projection chamber located at the 4850 ft level of the Sanford Underground Research Facility in Lead, SD. The first absolute charge (Qy) and light (Ly) measurement performed in situ in the LUX detector with a D-D calibration technique for nuclear recoil spanning 0.7 to 74 keV and 1.1 to 74 keV respectively have been reported in. The D-D calibration has subsequently been further improved by incorporating pulsing technique, i.e. the D-D neutron production is concentrated within narrow pulses (20 us / 250 Hz) with the timing information recorded. This technique allows the suppression of accidental backgrounds in D-D neutron data and also provides increased sensitivity for the lower energy NR calibrations. I will report the improved NR absolute Qy and Ly measurements using the pulsed D-D calibration technique performed in situ in the LUX detector. Brown University, Large Underground Xenon(LUX) Collaboration.

  12. Progress report on nuclear science and technology in China (Vol.3). Proceedings of academic annual meeting of China Nuclear Society in 2013, No.7--pulse power technology and its application sub-volume

    International Nuclear Information System (INIS)

    2014-05-01

    Progress report on nuclear science and technology in China (Vol. 3) includes 18 articles which are communicated on the third national academic annual meeting of China Nuclear Society. There are 10 books totally. This is the seventh one, the content is about pulse power technology and its application sub-volume

  13. Lightweight, Damage-Tolerant Radiator for In-Space Power and Propulsion

    Data.gov (United States)

    National Aeronautics and Space Administration — Nuclear-electric propulsion promises numerous advantages over other in-space propulsion technologies. However, one serious limitation is the mass of the radiator...

  14. Comparison of Orbit Transfer Vehicle Concepts Utilizing Mid-Term Power and Propulsion Options

    National Research Council Canada - National Science Library

    Gulczinski, Frank

    2002-01-01

    .... Therefore, the Air Force Research Laboratory Propulsion Directorate (AFRL/PRSS) has decided to reexamine the value of utilizing nuclear propulsion for orbit transit and the repositioning of future Air Force space assets...

  15. Pulsed Fission-Fusion Propulsion System

    Data.gov (United States)

    National Aeronautics and Space Administration — Leveraging insights gained from the weapons physics program, a Z-Pinch device could be used to ignite a thermonuclear deuterium trigger, which could provide a...

  16. Contrast generation in the nuclear-spin tomography by pulsed ultrasound; Kontrasterzeugung in der Kernspintomographie durch gepulsten Ultraschall

    Energy Technology Data Exchange (ETDEWEB)

    Oehms, Ole Benjamin

    2009-07-10

    In the framework of this thesis a combined method of ultrasound and nuclear-spin tomography is presented. Via ultrasound pulses by the sound-radiation force in liquids and tissue phantoms motions are generated, which depend on ther viscoelastic properties. This motions are made visible by a motion-sensitive tomograph sequence in the phase image of the tomograph in form of a phase change. The first measurements on simple phantoms and liquids are presented. [German] Im Rahmen dieser Arbeit wird eine kombinierte Methode aus Ultraschall und Kernspintomographie vorgestellt. Ueber Ultraschallpulse werden durch die Schallstrahlungskraft in Fluessigkeiten und Gewebephantomen Bewegungen erzeugt, die von den viskoelastischen Eigenschaften abhaengen. Diese Bewegungen werden mit einer bewegungssensitiven Tomographensequenz im Phasenbild des Tomographen in Form einer Phasenaenderung sichtbar gemacht. Die ersten Messungen an einfachen Phantomen und Fluessigkeiten werden praesentiert. (orig.)

  17. Comparison of electric dipole and magnetic dipole models for electromagnetic pulse generated by nuclear detonation in space

    International Nuclear Information System (INIS)

    Zhu Meng; Zhou Hui; Cheng Yinhui; Li Baozhong; Wu Wei; Li Jinxi; Ma Liang; Zhao Mo

    2013-01-01

    Electromagnetic pulse can be generated by the nuclear detonation in space via two radiation mechanisms. The electric dipole and magnetic dipole models were analyzed. The electric radiation in the far field generated by two models was calculated as well. Investigations show that in the case of one hundred TNT yield detonations, when electrons are emitted according to the Gaussian shape, two radiation models can give rise to the electric field in great distances with amplitudes of kV/m and tens of V/m, independently. Because the geomagnetic field in space is not strong and the electrons' angular motion is much weaker than the motion in the original direction, radiations from the magnetic dipole model are much weaker than those from the electric dipole model. (authors)

  18. Laser pulse heating of nuclear fuels for simulation of reactor power ...

    Indian Academy of Sciences (India)

    The safety of nuclear power reactors requires a thorough understanding of phenom- ena like loss of coolant accident (LOCA) and reactivity initiated accident (RIA). At high burnup, these phenomena become especially hazardous, as the probability of cladding failure goes up with the increased corrosion and hydriding [1].

  19. Laser pulse heating of nuclear fuels for simulation of reactor power ...

    Indian Academy of Sciences (India)

    of modifying the incident laser beam intensity distribution from the usual Gaussian to the shape of a typical temperature distribution in the nuclear fuel will be needed. This can be a suitably designed lens system. As the specimen is a thin wafer, the temperature distribution will closely resemble the power distribution.

  20. The optimization of the time resolution and the sensitivity in the pulsed nuclear resonance

    International Nuclear Information System (INIS)

    Umathum, R.

    1987-01-01

    The time resolution of pulsed NMR spectrometer and its spectral sensitivity are closely connected together. An important obstacle in the attempt to increase the resolution represents the dead time of the spectrometer. In the present thesis therefore the different contributions to the system dead time and their causes are analyzed and ways to the reduction respectively complete removement of a part of these contributions are indicated. So a duplexer was developed and constructed on the base of a principle novel for the NMR under application of quadrature hybrids which reduces the residual voltage of the sender pulse to less than 1/10 of the hitherto reached value. In this thesis a concept is extensively discussed which allows to generate at constant quality respectively damping constant of the sample circuit and given sender power a larger high frequency field strength than it is possible in the state of the power fitting. It could be shown than also concerning the noise behaviour by the application of the principle of the defined misfit no compromise must be made but it is even facilitated to approach the ideal of the noise fit of the first receiver stage to the sample circuit. (orig./HSI) [de

  1. MOVEMENT AND MANEUVER IN DEEP SPACE: A Framework to Leverage Advanced Propulsion

    Science.gov (United States)

    2018-04-01

    risks of pollution . Directed Energy-Driven Technology Just as in-situ resource utilization (ISRU) enables sustainable chemical propulsion in space... Chemical Propulsion – Advanced Cryogenic Evolved Stage (ACES) .......................................... 16 Nuclear-Thermal Propulsion (NTP) and...for energy production and transfer , including materials for manufacturing and maintenance, and to protect licit commerce.  The Joint Force requires

  2. The Prometheus 1 spacecraft preliminary electric propulsion system design

    Science.gov (United States)

    Randolph, Thomas M.; Dougherty, Ryan C.; Oleson, Steven R.; Fiehler, Douglas I.; Dipprey, Neil

    2005-01-01

    The proposed Prometheus 1 mission is an ambitious plan to orbit and explore the Jovian moons of Callisto, Ganymede, and Europa. Such an ambitious mission is enabled by the first interplanetary nuclear electric propulsion (EP) system.

  3. Detailed Characterization of Nuclear Recoil Pulse Shape Discrimination in the DarkSide-50 Direct Dark Matter Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Edkins, Erin Elisabeth [Univ. of Hawaii, Honolulu, HI (United States)

    2017-05-01

    While evidence of non-baryonic dark matter has been accumulating for decades, its exact nature continues to remain a mystery. Weakly Interacting Massive Particles (WIMPs) are a well motivated candidate which appear in certain extensions of the Standard Model, independently of dark matter theory. If such particles exist, they should occasionally interact with particles of normal matter, producing a signal which may be detected. The DarkSide-50 direct dark matter experiment aims to detect the energy of recoiling argon atoms due to the elastic scattering of postulated WIMPs. In order to make such a discovery, a clear understanding of both the background and signal region is essential. This understanding requires a careful study of the detector's response to radioactive sources, which in turn requires such sources may be safely introduced into or near the detector volume and reliably removed. The CALibration Insertaion System (CALIS) was designed and built for this purpose in a j oint effort between Fermi National Laboratory and the University of Hawaii. This work describes the design and testing of CALIS, its installation and commissioning at the Laboratori Nazionali del Gran Sasso (LNGS) and the multiple calibration campaigns which have successfully employed it. As nuclear recoils produced by WIMPs are indistinguishable from those produced by neutrons, radiogenic neutrons are both the most dangerous class of background and a vital calibration source for the study of the potential WIMP signal. Prior to the calibration of DarkSide-50 with radioactive neutron sources, the acceptance region was determined by the extrapolation of nuclear recoil data from a separate, dedicated experiment, ScENE, which measured the distribution of the pulse shape discrimination parameter, $f_{90}$, for nuclear recoils of known energies. This work demonstrates the validity of the extrapolation of ScENE values to DarkSide-50, by direct comparison of the $f_{90}$ distributio n of nuclear

  4. Response Analysis on Electrical Pulses under Severe Nuclear Accident Temperature Conditions Using an Abnormal Signal Simulation Analysis Module

    Directory of Open Access Journals (Sweden)

    Kil-Mo Koo

    2012-01-01

    Full Text Available Unlike design basis accidents, some inherent uncertainties of the reliability of instrumentations are expected while subjected to harsh environments (e.g., high temperature and pressure, high humidity, and high radioactivity occurring in severe nuclear accident conditions. Even under such conditions, an electrical signal should be within its expected range so that some mitigating actions can be taken based on the signal in the control room. For example, an industrial process control standard requires that the normal signal level for pressure, flow, and resistance temperature detector sensors be in the range of 4~20 mA for most instruments. Whereas, in the case that an abnormal signal is expected from an instrument, such a signal should be refined through a signal validation process so that the refined signal could be available in the control room. For some abnormal signals expected under severe accident conditions, to date, diagnostics and response analysis have been evaluated with an equivalent circuit model of real instruments, which is regarded as the best method. The main objective of this paper is to introduce a program designed to implement a diagnostic and response analysis for equivalent circuit modeling. The program links signal analysis tool code to abnormal signal simulation engine code not only as a one body order system, but also as a part of functions of a PC-based ASSA (abnormal signal simulation analysis module developed to obtain a varying range of the R-C circuit elements in high temperature conditions. As a result, a special function for abnormal pulse signal patterns can be obtained through the program, which in turn makes it possible to analyze the abnormal output pulse signals through a response characteristic of a 4~20 mA circuit model and a range of the elements changing with temperature under an accident condition.

  5. Propagation of ultrasonic pulses in the testing of nuclear reactor pressure vessels by means of acoustic emission

    International Nuclear Information System (INIS)

    Klot, R. von.

    1979-01-01

    Experiments are being conducted with a thick steel plate (d = 82,5 mm) and a large vessel (d = 22 mm) to investigate whether surface waves are excited when the sound source (ultrasonic transmitter) is several wavelengths below the surface where the receivers are located. It has been discovered that the amplitude value of the received signal, which is fixed using a discriminator threshold, propagates at the surface of both components at the velocity of the surface wave, which is 3.0 m/ms. In the case of a narrow-band transmitter and receiver with centre frequencies of 140 kHz, the bulk waves are so long that the flexural wave a 0 is excited by interference. In the case of thick plates the flexural wave turns into surface waves which propagate on both surfaces. When a broad-band receiver and transmitter with centre frequencies of 675 kHz are used, there is no excitation of plate waves since the bulk wave pulses are too short. In the latter configuration the received signal is composed of a number of bulk wave pulses, which, according to the above measurements of the sound velocity, give an envelope curve with the characteristic features of plate waves. In the case of the plate, the ultrasonic transmitter is correctly located for an amplitude range of 26 dB for both frequencies. The locating accuracy is approximately equal to the distance of the source from the surface. On the basis of this result, it is expected that the use of acoustic emission to test nuclear reactor pressure vessels will permit correct location of faults at all depths in the wall of the vessel, by means of the velocity of the surface wave. (orig.) [de

  6. Cold Gas Micro Propulsion

    NARCIS (Netherlands)

    Louwerse, M.C.

    2009-01-01

    This thesis describes the development of a micro propulsion system. The trend of miniaturization of satellites requires small sized propulsion systems. For particular missions it is important to maintain an accurate distance between multiple satellites. Satellites drift apart due to differences in

  7. Study and fabrication of a broadband receiver with frequency change for a spectrometer by Nuclear Magnetic Resonance based on pulse in liquids

    International Nuclear Information System (INIS)

    Avril, Robert

    1974-01-01

    The objective of this work has been, by using the pulsed NMR technique, to study and produce a set for the reception of the nuclear precession signal for a broadband (1-60 MHz) spectrometer. In a first part, the author recalls some fundamental elements of pulsed NMR, and discusses the assessment of the precession signal amplitude which can be expected. Then, he gives a detailed description of the various components of the reception chain (modulator, amplifiers, broadband pre-amplifiers, diode gate, frequency changer, synchronous detection), and, through experimentation and measurements, outlines the ease of implementation and adaptation to measurement conditions

  8. Satellite auxiliary-propulsion selection techniques. Addendum: A survey of auxiliary electric propulsion systems

    Science.gov (United States)

    Holcomb, L. B.

    1971-01-01

    A review of electric thrusters for satellite auxiliary propulsion was conducted at JPL during the past year. Comparisons of the various thrusters for attitude propulsion and east-west and north-south stationkeeping were made based upon performance, mass, power, and demonstrated life. Reliability and cost are also discussed. The method of electrical acceleration of propellant served to divide the thruster systems into two groups: electrostatic and electromagnetic. Ion and colloid thrusters fall within the electrostatically accelerated group while MPD and pulsed plasma thrusters comprise the electromagnetically accelerated group. The survey was confined to research in the United States with accent on flight and flight prototype systems.

  9. Contamination Study of Micro Pulsed Plasma Thruster

    National Research Council Canada - National Science Library

    Kesenek, Ceylan

    2008-01-01

    .... Micro-Pulsed Plasma Thrusters (PPTs) are highly reliable and simple micro propulsion systems that will offer attitude control, station keeping, constellation flying, and drag compensation for such satellites...

  10. Distributed Propulsion Vehicles

    Science.gov (United States)

    Kim, Hyun Dae

    2010-01-01

    Since the introduction of large jet-powered transport aircraft, the majority of these vehicles have been designed by placing thrust-generating engines either under the wings or on the fuselage to minimize aerodynamic interactions on the vehicle operation. However, advances in computational and experimental tools along with new technologies in materials, structures, and aircraft controls, etc. are enabling a high degree of integration of the airframe and propulsion system in aircraft design. The National Aeronautics and Space Administration (NASA) has been investigating a number of revolutionary distributed propulsion vehicle concepts to increase aircraft performance. The concept of distributed propulsion is to fully integrate a propulsion system within an airframe such that the aircraft takes full synergistic benefits of coupling of airframe aerodynamics and the propulsion thrust stream by distributing thrust using many propulsors on the airframe. Some of the concepts are based on the use of distributed jet flaps, distributed small multiple engines, gas-driven multi-fans, mechanically driven multifans, cross-flow fans, and electric fans driven by turboelectric generators. This paper describes some early concepts of the distributed propulsion vehicles and the current turboelectric distributed propulsion (TeDP) vehicle concepts being studied under the NASA s Subsonic Fixed Wing (SFW) Project to drastically reduce aircraft-related fuel burn, emissions, and noise by the year 2030 to 2035.

  11. Advanced Propulsion Research Interest in Materials for Propulsion

    Science.gov (United States)

    Cole, John

    2003-01-01

    This viewgraph presentation provides an overview of material science and technology in the area of propulsion energetics. The authors note that conventional propulsion systems are near peak performance and further refinements in manufacturing, engineering design and materials will only provide incremental increases in performance. Energetic propulsion technologies could potential solve the problems of energy storage density and energy-to-thrust conversion efficiency. Topics considered include: the limits of thermal propulsion systems, the need for energetic propulsion research, emerging energetic propulsion technologies, materials research needed for advanced propulsion, and potential research opportunities.

  12. Thermal Propulsion Capture System Heat Exchanger Design

    Science.gov (United States)

    Richard, Evan M.

    2016-01-01

    One of the biggest challenges of manned spaceflight beyond low earth orbit and the moon is harmful radiation that astronauts would be exposed to on their long journey to Mars and further destinations. Using nuclear energy has the potential to be a more effective means of propulsion compared to traditional chemical engines (higher specific impulse). An upper stage nuclear engine would allow astronauts to reach their destination faster and more fuel efficiently. Testing these engines poses engineering challenges due to the need to totally capture the engine exhaust. The Thermal Propulsion Capture System is a concept for cost effectively and safely testing Nuclear Thermal Engines. Nominally, hydrogen exhausted from the engine is not radioactive, but is treated as such in case of fuel element failure. The Thermal Propulsion Capture System involves injecting liquid oxygen to convert the hydrogen exhaust into steam. The steam is then cooled and condensed into liquid water to allow for storage. The Thermal Propulsion Capture System concept for ground testing of a nuclear powered engine involves capturing the engine exhaust to be cooled and condensed before being stored. The hydrogen exhaust is injected with liquid oxygen and burned to form steam. That steam must be cooled to saturation temperatures before being condensed into liquid water. A crossflow heat exchanger using water as a working fluid will be designed to accomplish this goal. Design a cross flow heat exchanger for the Thermal Propulsion Capture System testing which: Eliminates the need for water injection cooling, Cools steam from 5800 F to saturation temperature, and Is efficient and minimizes water requirement.

  13. Ship propulsion reactors technology

    International Nuclear Information System (INIS)

    Fribourg, Ch.

    2002-01-01

    This paper takes the state of the art on ship propulsion reactors technology. The french research programs with the corresponding technological stakes, the reactors specifications and advantages are detailed. (A.L.B.)

  14. Alternative propulsion for automobiles

    CERN Document Server

    Stan, Cornel

    2017-01-01

    The book presents – based on the most recent research and development results worldwide - the perspectives of new propulsion concepts such as electric cars with batteries and fuel cells, and furthermore plug in hybrids with conventional and alternative fuels. The propulsion concepts are evaluated based on specific power, torque characteristic, acceleration behaviour, specific fuel consumption and pollutant emissions. The alternative fuels are discussed in terms of availability, production, technical complexity of the storage on board, costs, safety and infrastructure. The book presents summarized data about vehicles with electric and hybrid propulsion. The propulsion of future cars will be marked by diversity – from compact electric city cars and range extender vehicles for suburban and rural areas up to hybrid or plug in SUV´s, Pick up´s and luxury class automobiles.

  15. Electromagnetic Pulse Coupling Analysis of Electronic Equipment

    OpenAIRE

    Hong Lei; Qingying LI

    2017-01-01

    High-intensity nuclear explosion caused by high-altitude nuclear electromagnetic pulse through the antenna, metal cables, holes and other channels, coupled with very high energy into the electronic device, and cause serious threats. In this paper, the mechanism, waveform, coupling path and damage effect of nuclear electromagnetic pulse is analyzed, and the coupling mechanism of nuclear electromagnetic pulse is studied.

  16. Analysis of ultrasound propagation in high-temperature nuclear reactor feedwater to investigate a clamp-on ultrasonic pulse doppler flowmeter

    International Nuclear Information System (INIS)

    Tezuka, Kenichi; Mori, Michitsugu; Wada, Sanehiro; Aritomi, Masanori; Kikura, Hiroshige; Sakai, Yukihiro

    2008-01-01

    The flow rate of nuclear reactor feedwater is an important factor in the operation of a nuclear power reactor. Venturi nozzles are widely used to measure the flow rate. Other types of flowmeters have been proposed to improve measurement accuracy and permit the flow rate and reactor power to be increased. The ultrasonic pulse Doppler system is expected to be a candidate method because it can measure the flow profile across the pipe cross section, which changes with time. For accurate estimation of the flow velocity, the incidence angle of ultrasound entering the fluid should be estimated using Snell's law. However, evaluation of the ultrasound propagation is not straightforward, especially for a high-temperature pipe with a clamp-on ultrasonic Doppler flowmeter. The ultrasound beam path may differ from what is expected from Snell's law due to the temperature gradient in the wedge and variation in the acoustic impedance between interfaces. Recently, simulation code for ultrasound propagation has come into use in the nuclear field for nondestructive testing. This article analyzes and discusses ultrasound propagation, using 3D-FEM simulation code plus the Kirchhoff method, as it relates to flow profile measurement in nuclear reactor feedwater with the ultrasonic pulse Doppler system. (author)

  17. 76 FR 37798 - DOE Response to Recommendation 2010-2 of the Defense Nuclear Facilities Safety Board, Pulse Jet...

    Science.gov (United States)

    2011-06-28

    ... demonstrate that representative samples can be taken from waste feed delivery tanks to meet the Waste... Safety Board, Pulse Jet Mixing at the Waste Treatment and Immobilization Plant AGENCY: Department of... their Recommendation 2010-2, concerning Pulse Jet Mixing at the Waste Treatment and Immobilization Plant...

  18. Nanosatellite Propulsion Development Program

    Science.gov (United States)

    Gagosian, J. S.; Rhee, M. S.; Zakrzwski, C. M.

    1999-01-01

    Earth-orbiting nanosatellite constellations are a unique and exciting means toward fulfilling part of the mission of the Goddard Space Flight Center (GSFC). These constellations, which may consist of several hundred 10-kg spacecraft, present unique challenges in the area of propulsion. Many mission concepts require significant delta-v and attitude control capability to reside in the nanosatellites. In response to requirements from mission feasibility studies, such as the Magnetospheric Constellation study, the GSFC has initiated industry and government partnerships to develop enabling propulsion technologies. The largest challenge has been to meet the power constraints of nanosatellites. These power issues, combined with the high thrust required by many of the missions studied, have led the GSFC to concentrate its efforts on chemical propulsion technology. Electric propulsion technologies capable of performing efficiently at very low power are also of interest to the GSFC as potential candidates for nanosatellite formation flying missions. This paper provides the status of specific industrial or government partnerships undertaken by the GSFC to develop nano/micro propulsion components. Three specific technologies are described in detail: 1) Nanosatellite Solid Rocket Motor Prototype 2) Ultra-Low-Power Cold Gas Thruster for Spin-Axis Precession 3) Micro-Machined Solid-Propellant Gas Generators.

  19. Parametric studies of electric propulsion systems for orbit transfer vehicles

    Science.gov (United States)

    Manvi, R.; Fujita, T.

    1988-01-01

    The present parametric tradeoff study for OTV electric propulsion systems encompasses ammonia and hydrogen arcjets as well as Xe-ion propulsion systems with performance characteristics currently being projected for 1993 operation. In all cases, the power source is a nuclear-electric system with 30 kg/kW(e) specific mass, and the mission involves the movement of payloads from lower orbits to GEO. Attention is given to payload capabilities and associated propellant requirements. Mission trip time is identified as the key parameter for selection; while arcjets are preferable for shorter trip times, ion propulsion is more advantageous for longer trip times due to reduced propellant mass fraction.

  20. Propulsion controlled aircraft computer

    Science.gov (United States)

    Cogan, Bruce R. (Inventor)

    2010-01-01

    A low-cost, easily retrofit Propulsion Controlled Aircraft (PCA) system for use on a wide range of commercial and military aircraft consists of an propulsion controlled aircraft computer that reads in aircraft data including aircraft state, pilot commands and other related data, calculates aircraft throttle position for a given maneuver commanded by the pilot, and then displays both current and calculated throttle position on a cockpit display to show the pilot where to move throttles to achieve the commanded maneuver, or is automatically sent digitally to command the engines directly.

  1. Airbreathing Propulsion An Introduction

    CERN Document Server

    Bose, Tarit

    2012-01-01

    Airbreathing Propulsion covers the physics of combustion, fluid and thermo-dynamics, and structural mechanics of airbreathing engines, including piston, turboprop, turbojet, turbofan, and ramjet engines. End-of-chapter exercises allow the reader to practice the fundamental concepts behind airbreathing propulsion, and the included PAGIC computer code will help the reader to examine the relationships between the performance parameters of different engines. Large amounts of data on many different piston, turbojet, and turboprop engines have been compiled for this book and are included as an appendix. This textbook is ideal for senior undergraduate and graduate students studying aeronautical engineering, aerospace engineering, and mechanical engineering.

  2. Space transportation propulsion USSR launcher technology, 1990

    Science.gov (United States)

    1991-01-01

    Space transportation propulsion U.S.S.R. launcher technology is discussed. The following subject areas are covered: Energia background (launch vehicle summary, Soviet launcher family) and Energia propulsion characteristics (booster propulsion, core propulsion, and growth capability).

  3. NASA Electric Propulsion System Studies

    Science.gov (United States)

    Felder, James L.

    2015-01-01

    An overview of NASA efforts in the area of hybrid electric and turboelectric propulsion in large transport. This overview includes a list of reasons why we are looking at transmitting some or all of the propulsive power for the aircraft electrically, a list of the different types of hybrid-turbo electric propulsion systems, and the results of 4 aircraft studies that examined different types of hybrid-turbo electric propulsion systems.

  4. TOWARDS THE ELECTRIC PROPULSION

    Directory of Open Access Journals (Sweden)

    Mihai Victor PRICOP

    2010-03-01

    Full Text Available The paper presents benefits and drawbacks of the electric propulsion for the case of a ten seat commuter aircraft. An efficiency evaluation is made for an electric version of AEROTAXI, considered as a reference. The evaluation is projected to 2020, trying to meet the expected progresses in energy storage systems.

  5. Laser propulsion: a review

    CSIR Research Space (South Africa)

    Michaelis, MM

    2006-07-01

    Full Text Available -of-magnitude reduction in launch costs. American, German and Japanese experimental ‘lightcraft’ are described as well as the Orion programme to de-orbit space debris. Marx’s seminal paper on laser-driven, relativistic space propulsion and the ensuing controversy was also...

  6. Turboprop Propulsion Mechanic.

    Science.gov (United States)

    Chanute AFB Technical Training Center, IL.

    This instructional package consists of a plan of instruction, glossary, and student handouts and exercises for use in training Air Force personnel to become turboprop propulsion mechanics. Addressed in the individual lessons of the course are the following: common hand tools, hardware, measuring devices, and safety wiring; aircraft and engine…

  7. Pulsed neutron generator

    International Nuclear Information System (INIS)

    Bespalov, D.F.; Bykovskii, Yu.A.; Vergun, I.I.; Kozlovskii, K.I.; Kozyrev, Yu.P.; Leonov, R.K.; Simagin, B.I.; Tsybin, A.S.; Shikanov, A.Ie.

    1986-03-01

    The paper describes a new device for generating pulsed neutron fields, utilized in nuclear geophysics for carrying out pulsed neutron logging and activation analysis under field conditions. The invention employs a sealed-off neutron tube with a laser ion source which increases neutron yield to the level of 10 neutrons per second or higher. 2 refs., 1 fig

  8. Pulse radiolysis

    International Nuclear Information System (INIS)

    Greenshields, H.; Seddon, W.A.

    1982-03-01

    This supplement to two bibliographies published in 1970 and 1972 lists 734 references to the literature of pulse radiolysis, arranged under eight broad subject headings. The references were compiled by searching Biological Abstracts, Chemical Abstracts, Nuclear Science Abstracts and the Weekly List of Papers in Radiation Chemistry issued by the Radiation Chemistry Data Center of Notre Dame University. Full bibliographic data is given for papers published in the period 1971 to 1974. A personal author index listing more than 600 authors and a similar number of co-authors is included

  9. Outer Planet Missions with Electric Propulsion Systems—Part I

    Directory of Open Access Journals (Sweden)

    Carlos Renato Huaura Solórzano

    2010-01-01

    Full Text Available For interplanetary missions, efficient electric propulsion systems can be used to increase the mass delivered to the destination. Outer planet exploration has experienced new interest with the launch of the Cassini and New Horizons Missions. At the present, new technologies are studied for better use of electric propulsion systems in missions to the outer planets. This paper presents low-thrust trajectories using the method of the transporting trajectory to Uranus, Neptune, and Pluto. They use nuclear and radio isotopic electric propulsion. These direct transfers have continuous electric propulsion of low power along the entire trajectory. The main goal of the paper is to optimize the transfers, that is, to provide maximum mass to be delivered to the outer planets.

  10. Hydrodynamics of Peristaltic Propulsion

    Science.gov (United States)

    Athanassiadis, Athanasios; Hart, Douglas

    2014-11-01

    A curious class of animals called salps live in marine environments and self-propel by ejecting vortex rings much like jellyfish and squid. However, unlike other jetting creatures that siphon and eject water from one side of their body, salps produce vortex rings by pumping water through siphons on opposite ends of their hollow cylindrical bodies. In the simplest cases, it seems like some species of salp can successfully move by contracting just two siphons connected by an elastic body. When thought of as a chain of timed contractions, salp propulsion is reminiscent of peristaltic pumping applied to marine locomotion. Inspired by salps, we investigate the hydrodynamics of peristaltic propulsion, focusing on the scaling relationships that determine flow rate, thrust production, and energy usage in a model system. We discuss possible actuation methods for a model peristaltic vehicle, considering both the material and geometrical requirements for such a system.

  11. 76 FR 13397 - DOE Response to Recommendation 2010-2 of the Defense Nuclear Facilities Safety Board, Pulse Jet...

    Science.gov (United States)

    2011-03-11

    ... Hanford Tank Farms.'' DOE intends to conduct large-scale testing with simulants selected to represent the vast majority of the waste in the tank farms, consistent with the approach used in WTP's pulse jet... equipment for vessel heel dilution and cleanout, that would enable waste particles that may not be mixing...

  12. Why Density Dependent Propulsion?

    Science.gov (United States)

    Robertson, Glen A.

    2011-01-01

    In 2004 Khoury and Weltman produced a density dependent cosmology theory they call the Chameleon, as at its nature, it is hidden within known physics. The Chameleon theory has implications to dark matter/energy with universe acceleration properties, which implies a new force mechanism with ties to the far and local density environment. In this paper, the Chameleon Density Model is discussed in terms of propulsion toward new propellant-less engineering methods.

  13. Propulsion for CubeSats

    Science.gov (United States)

    Lemmer, Kristina

    2017-05-01

    At present, very few CubeSats have flown in space featuring propulsion systems. Of those that have, the literature is scattered, published in a variety of formats (conference proceedings, contractor websites, technical notes, and journal articles), and often not available for public release. This paper seeks to collect the relevant publically releasable information in one location. To date, only two missions have featured propulsion systems as part of the technology demonstration. The IMPACT mission from the Aerospace Corporation launched several electrospray thrusters from Massachusetts Institute of Technology, and BricSAT-P from the United States Naval Academy had four micro-Cathode Arc Thrusters from George Washington University. Other than these two missions, propulsion on CubeSats has been used only for attitude control and reaction wheel desaturation via cold gas propulsion systems. As the desired capability of CubeSats increases, and more complex missions are planned, propulsion is required to accomplish the science and engineering objectives. This survey includes propulsion systems that have been designed specifically for the CubeSat platform and systems that fit within CubeSat constraints but were developed for other platforms. Throughout the survey, discussion of flight heritage and results of the mission are included where publicly released information and data have been made available. Major categories of propulsion systems that are in this survey are solar sails, cold gas propulsion, electric propulsion, and chemical propulsion systems. Only systems that have been tested in a laboratory or with some flight history are included.

  14. Pulse holographic measurement techniques

    International Nuclear Information System (INIS)

    Kim, Cheol Jung; Baik, Seong Hoon; Hong, Seok Kyung; Kim, Jeong Moog; Kim, Duk Hyun

    1992-01-01

    With the development of laser, remote inspection techniques using laser have been growing on. The inspection and measurement techniques by pulse holography are well-established technique for precise measurement, and widely used in various fields of industry now. In nuclear industry, this technology is practically used because holographic inspection is remote, noncontact, and precise measurement technique. In relation to remote inspection technology in nuclear industry, state-of-the art of pulse HNDT (Holographic non-destructive testing) and holographic measurement techniques are examined. First of all, the fundamental principles as well as practical problems for applications are briefly described. The fields of pulse holography have been divided into the HNDT, flow visualization and distribution study, and other application techniques. Additionally holographic particle study, bubble chamber holography, and applications to other visualization techniques are described. Lastly, the current status for the researches and applications of pulse holography to nuclear industry which are carried out actively in Europe and USA, is described. (Author)

  15. Green Electric Monopropellant (GEM) Fueled Pulsed Plasma Thruster, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Digital Solid State Propulsion is proposing the development of a new liquid Pulsed Plasma Thruster (PPT) using its revolutionary HAN-based Green Electric...

  16. NASA Breakthrough Propulsion Physics Program

    Science.gov (United States)

    Millis, Marc G.

    1998-01-01

    In 1996, NASA established the Breakthrough Propulsion Physics program to seek the ultimate breakthroughs in space transportation: propulsion that requires no propellant mass, propulsion that attains the maximum transit speeds physically possible, and breakthrough methods of energy production to power such devices. Topics of interest include experiments and theories regarding the coupling of gravity and electromagnetism, vacuum fluctuation energy, warp drives and worm-holes, and superluminal quantum effects. Because these propulsion goals are presumably far from fruition, a special emphasis is to identify affordable, near-term, and credible research that could make measurable progress toward these propulsion goals. The methods of the program and the results of the 1997 workshop are presented. This Breakthrough Propulsion Physics program, managed by Lewis Research Center, is one part of a comprehensive, long range Advanced Space Transportation Plan managed by Marshall Space Flight Center.

  17. Electrolysis Propulsion for Spacecraft Applications

    Science.gov (United States)

    deGroot, Wim A.; Arrington, Lynn A.; McElroy, James F.; Mitlitsky, Fred; Weisberg, Andrew H.; Carter, Preston H., II; Myers, Blake; Reed, Brian D.

    1997-01-01

    Electrolysis propulsion has been recognized over the last several decades as a viable option to meet many satellite and spacecraft propulsion requirements. This technology, however, was never used for in-space missions. In the same time frame, water based fuel cells have flown in a number of missions. These systems have many components similar to electrolysis propulsion systems. Recent advances in component technology include: lightweight tankage, water vapor feed electrolysis, fuel cell technology, and thrust chamber materials for propulsion. Taken together, these developments make propulsion and/or power using electrolysis/fuel cell technology very attractive as separate or integrated systems. A water electrolysis propulsion testbed was constructed and tested in a joint NASA/Hamilton Standard/Lawrence Livermore National Laboratories program to demonstrate these technology developments for propulsion. The results from these testbed experiments using a I-N thruster are presented. A concept to integrate a propulsion system and a fuel cell system into a unitized spacecraft propulsion and power system is outlined.

  18. Electric Propulsion Research Building (EPRB)

    Data.gov (United States)

    Federal Laboratory Consortium — The Electric Propulsion Research Building (EPRB) capability centers on its suite of vacuum chambers, which are configured to meet the unique requirements related to...

  19. Oscillating foil propulsion

    OpenAIRE

    Hauge, Jacob

    2013-01-01

    Unsteady foil theory is discussed and applied on several cases of an oscillating foil. The oscillating foil is meant as a propulsion system for a platform supply vessel.Four case studies of foil oscillation have been performed. A thrust coefficient of 0.1 was achieved at an efficiency of 0.75. A thrust coefficient of minimum 0.184 is necessary to overcome the calm water resistance of the foil.Issues connected to coupled vessel-foil models are discussed.

  20. Shielding requirements for particle bed propulsion systems

    Science.gov (United States)

    Gruneisen, S. J.

    1991-06-01

    Nuclear Thermal Propulsion systems present unique challenges in reliability and safety. Due to the radiation incident upon all components of the propulsion system, shielding must be used to keep nuclear heating in the materials within limits; in addition, electronic control systems must be protected. This report analyzes the nuclear heating due to the radiation and the shielding required to meet the established criteria while also minimizing the shield mass. Heating rates were determined in a 2000 MWt Particle Bed Reactor (PBR) system for all materials in the interstage region, between the reactor vessel and the propellant tank, with special emphasis on meeting the silicon dose criteria. Using a Lithium Hydride/Tungsten shield, the optimum shield design was found to be: 50 cm LiH/2 cm W on the axial reflector in the reactor vessel and 50 cm LiH/2 cm W in a collar extension of the inside shield outside of the pressure vessel. Within these parameters, the radiation doses in all of the components in the interstage and lower tank regions would be within acceptable limits for mission requirements.

  1. A comparison of lightning electromagnetic fields with the nuclear electromagnetic pulse in the frequency range 10 to the 4th to 10 to the 7th Hz

    International Nuclear Information System (INIS)

    Uman, M.A.; Master, M.J.; Krider, E.P.

    1982-01-01

    The electromagnetic fields produced by both direct lightning strikes and nearby lightning are compared with the nuclear electromagnetic pulse (NEMP) from an exoatmospheric burst. Model calculations indicate that, in the frequency range from 10 kHz to near 10 MHz, the Fourier amplitude spectra of the return stroke magnetic fields near ground 1 m from an average lightning strike will exceed that of the NEMP. Nearby first return strokes at a range of about 50 m, if they are severe, produce electric field spectra near ground which exceed that of the NEMP below about 1 MHz, while the spectra of average nearby first return strokes exceed that of the NEMP below about 300 kHz. Implications of these results for aircraft in flight are discussed

  2. Dual-mode Propulsion System Enabling CubeSat Exploration of the Solar System

    Data.gov (United States)

    National Aeronautics and Space Administration — Researchers at the Center for Space Nuclear Research (CSNR) are proposing a radioisotope-based, dual-mode, low mass propulsion system for a CubeSat payload capable...

  3. An Affordable Autonomous Hydrogen Flame Detection System for Rocket Propulsion, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA has long used liquid hydrogen as a fuel and plans to continue using it in association with their advanced nuclear thermal propulsion technology. Hydrogen fire...

  4. Additive Manufacturing of Aerospace Propulsion Components

    Science.gov (United States)

    Misra, Ajay K.; Grady, Joseph E.; Carter, Robert

    2015-01-01

    The presentation will provide an overview of ongoing activities on additive manufacturing of aerospace propulsion components, which included rocket propulsion and gas turbine engines. Future opportunities on additive manufacturing of hybrid electric propulsion components will be discussed.

  5. Measurements of energetic ions produced by high-energy laser pulses by means of solid-state nuclear track detectors

    Czech Academy of Sciences Publication Activity Database

    Szydlowski, A.; Badziak, A.; Parys, P.; Wolowski, J.; Woryna, E.; Jungwirth, Karel; Králiková, Božena; Krása, Josef; Láska, Leoš; Pfeifer, Miroslav; Rohlena, Karel; Skála, Jiří; Ullschmied, Jiří; Boody, F. D.; Gammino, S.; Torrisi, L.

    2004-01-01

    Roč. 7, č. 3 (2004), s. 327-332 ISSN 1093-3611 Institutional research plan: CEZ:AV0Z1010921 Keywords : iodine laser * nuclear track detectors * ions Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.194, year: 2004

  6. Sunken nuclear submarines

    International Nuclear Information System (INIS)

    Eriksen, V.O.

    1990-01-01

    The increasing number of accidents with nuclear submarines is a worriment to the general public. Five nuclear submarines are resting on the bottom of the North Atlantic. Design information on nuclear propulsion plants for submarines is classified. The author describes a potential generic nuclear submarine propulsion plant. Design information from the civilian nuclear industry, nuclear power plants, research reactors, nuclear cargo vessels and nuclear propelled icebreakers are used for illustration of relevant problems. A survey is given of nuclear submarines. Factors influencing the accident risks and safety characteristics of nuclear submarines are considered, and potential accident scenarios are described. The fission product content of the nuclear plant can be estimated, '' source terms'' can be guessed and potential release rates can be judged. The mechanisms of dispersion in the oceans is reviewed and compared with the dumping of radioactive waste in the Atlantic and other known releases. 46 refs., 49 figs., 14 tabs

  7. NEP heat pipe radiators. [Nuclear Electric Propulsion

    Science.gov (United States)

    Ernst, D. M.

    1979-01-01

    This paper covers improvements of heat pipe radiators for the thermionic NEP design. Liquid metal heat pipes are suitable as spacecraft radiator elements because of high thermal conductance, low mass and reliability, but the NEP thermionic system design was too large and difficult to fabricate. The current integral collector-radiator design consisting of several layers of thermionic converters, the annular-tangential collector heat pipe, the radiator heat pipe, and the transition zone designed to minimize the temperature difference between the collector heat pipe and radiator heat pipe are described. Finally, the design of micrometeoroid armor protection and the fabrication of the stainless steel annular heat pipe with a tangential arm are discussed, and it is concluded that the heat rejection system for the thermionic NEP system is well advanced, but the collector-radiator heat pipe transition and the 8 to 10 m radiator heat pipe with two bends require evaluation.

  8. Monofilament Vaporization Propulsion (MVP) System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Monofilament Vaporization Propulsion (MVP) is a new propulsion technology targeted at secondary payload applications. It does not compromise on performance while...

  9. Monofilament Vaporization Propulsion (MVP) System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Monofilament Vaporization Propulsion (MVP) is an innovative new propulsion technology targeted at secondary payload applications. The approach with MVP, rather than...

  10. In-Space Propulsion (346620) Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Technologies include, but are not limited to, electric and advanced chemical propulsion, propellantless propulsion such as aerocapture and solar sails, sample return...

  11. Innovative Approaches to Development and Ground Testing of Advanced Bimodal Space Power and Propulsion Systems

    International Nuclear Information System (INIS)

    Hill, T.; Noble, C.; Martinell, J.; Borowski, S.

    2000-01-01

    The last major development effort for nuclear power and propulsion systems ended in 1993. Currently, there is not an initiative at either the National Aeronautical and Space Administration (NASA) or the U.S. Department of Energy (DOE) that requires the development of new nuclear power and propulsion systems. Studies continue to show nuclear technology as a strong technical candidate to lead the way toward human exploration of adjacent planets or provide power for deep space missions, particularly a 15,000 lbf bimodal nuclear system with 115 kW power capability. The development of nuclear technology for space applications would require technology development in some areas and a major flight qualification program. The last major ground test facility considered for nuclear propulsion qualification was the U.S. Air Force/DOE Space Nuclear Thermal Propulsion Project. Seven years have passed since that effort, and the questions remain the same, how to qualify nuclear power and propulsion systems for future space flight. It can be reasonably assumed that much of the nuclear testing required to qualify a nuclear system for space application will be performed at DOE facilities as demonstrated by the Nuclear Rocket Engine Reactor Experiment (NERVA) and Space Nuclear Thermal Propulsion (SNTP) programs. The nuclear infrastructure to support testing in this country is aging and getting smaller, though facilities still exist to support many of the technology development needs. By renewing efforts, an innovative approach to qualifying these systems through the use of existing facilities either in the U.S. (DOE's Advance Test Reactor, High Flux Irradiation Facility and the Contained Test Facility) or overseas should be possible

  12. Development of graded Ni-YSZ composite coating on Alloy 690 by Pulsed Laser Deposition technique to reduce hazardous metallic nuclear waste inventory.

    Science.gov (United States)

    Sengupta, Pranesh; Rogalla, Detlef; Becker, Hans Werner; Dey, Gautam Kumar; Chakraborty, Sumit

    2011-08-15

    Alloy 690 based 'nuclear waste vitrification furnace' components degrade prematurely due to molten glass-alloy interactions at high temperatures and thereby increase the volume of metallic nuclear waste. In order to reduce the waste inventory, compositionally graded Ni-YSZ (Y(2)O(3) stabilized ZrO(2)) composite coating has been developed on Alloy 690 using Pulsed Laser Deposition technique. Five different thin-films starting with Ni80YSZ20 (Ni 80 wt%+YSZ 20 wt%), through Ni60YSZ40 (Ni 60 wt%+YSZ 40 wt%), Ni40YSZ60 (Ni 40 wt%+YSZ 60 wt%), Ni20YSZ80 (Ni 20 wt%+YSZ 80 wt%) and Ni0YSZ100 (Ni 0 wt%+YSZ 100 wt%), were deposited successively on Alloy 690 coupons. Detailed analyses of the thin-films identify them as homogeneous, uniform, pore free and crystalline in nature. A comparative study of coated and uncoated Alloy 690 coupons, exposed to sodium borosilicate melt at 1000°C for 1-6h suggests that the graded composite coating could substantially reduced the chemical interactions between Alloy 690 and borosilicate melt. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Magnetohydrodynamic Augmented Propulsion Experiment

    Science.gov (United States)

    Litchford, Ron J.; Cole, John; Lineberry, John; Chapman, Jim; Schmidt, Harold; Cook, Stephen (Technical Monitor)

    2002-01-01

    A fundamental obstacle to routine space access is the specific energy limitations associated with chemical fuels. In the case of vertical take-off, the high thrust needed for vertical liftoff and acceleration to orbit translates into power levels in the 10 GW range. Furthermore, useful payload mass fractions are possible only if the exhaust particle energy (i.e., exhaust velocity) is much greater than that available with traditional chemical propulsion. The electronic binding energy released by the best chemical reactions (e.g., LOX/LH2 for example, is less than 2 eV per product molecule (approx. 1.8 eV per H2O molecule), which translates into particle velocities less than 5 km/s. Useful payload fractions, however, will require exhaust velocities exceeding 15 km/s (i.e., particle energies greater than 20 eV). As an added challenge, the envisioned hypothetical RLV (reusable launch vehicle) should accomplish these amazing performance feats while providing relatively low acceleration levels to orbit (2-3g maximum). From such fundamental considerations, it is painfully obvious that planned and current RLV solutions based on chemical fuels alone represent only a temporary solution and can only result in minor gains, at best. What is truly needed is a revolutionary approach that will dramatically reduce the amount of fuel and size of the launch vehicle. This implies the need for new compact high-power energy sources as well as advanced accelerator technologies for increasing engine exhaust velocity. Electromagnetic acceleration techniques are of immense interest since they can be used to circumvent the thermal limits associated with conventional propulsion systems. This paper describes the Magnetohydrodynamic Augmented Propulsion Experiment (MAPX) being undertaken at NASA Marshall Space Flight Center (MSFC). In this experiment, a 1-MW arc heater is being used as a feeder for a 1-MW magnetohydrodynamic (MHD) accelerator. The purpose of the experiment is to demonstrate

  14. Electric propulsion system technology

    Science.gov (United States)

    Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.; Pivirotto, Thomas J.; Polk, James E.

    1992-01-01

    The work performed in fiscal year (FY) 1991 under the Propulsion Technology Program RTOP (Research and Technology Objectives and Plans) No. (55) 506-42-31 for Low-Thrust Primary and Auxiliary Propulsion technology development is described. The objectives of this work fall under two broad categories. The first of these deals with the development of ion engines for primary propulsion in support of solar system exploration. The second with the advancement of steady-state magnetoplasmadynamic (MPD) thruster technology at 100 kW to multimegawatt input power levels. The major technology issues for ion propulsion are demonstration of adequate engine life at the 5 to 10 kW power level and scaling ion engines to power levels of tens to hundreds of kilowatts. Tests of a new technique in which the decelerator grid of a three-grid ion accelerator system is biased negative of neutralizer common potential in order to collect facility induced charge-exchange ions are described. These tests indicate that this SAND (Screen, Accelerator, Negative Decelerator) configuration may enable long duration ion engine endurance tests to be performed at vacuum chamber pressures an order of magnitude higher than previously possible. The corresponding reduction in pumping speed requirements enables endurance tests of 10 kW class ion engines to be performed within the resources of existing technology programs. The results of a successful 5,000-hr endurance of a xenon hollow cathode operating at an emission current of 25 A are described, as well as the initial tests of hollow cathodes operating on a mixture of argon and 3 percent nitrogen. Work performed on the development of carbon/carbon grids, a multi-orifice hollow cathode, and discharge chamber erosion reduction through the addition of nitrogen are also described. Critical applied-field MPD thruster technical issues remain to be resolved, including demonstration of reliable steady-state operation at input powers of hundreds to thousands of

  15. Electric propulsion system technology

    Science.gov (United States)

    Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.; Pivirotto, Thomas J.; Polk, James E.

    1992-11-01

    The work performed in fiscal year (FY) 1991 under the Propulsion Technology Program RTOP (Research and Technology Objectives and Plans) No. (55) 506-42-31 for Low-Thrust Primary and Auxiliary Propulsion technology development is described. The objectives of this work fall under two broad categories. The first of these deals with the development of ion engines for primary propulsion in support of solar system exploration. The second with the advancement of steady-state magnetoplasmadynamic (MPD) thruster technology at 100 kW to multimegawatt input power levels. The major technology issues for ion propulsion are demonstration of adequate engine life at the 5 to 10 kW power level and scaling ion engines to power levels of tens to hundreds of kilowatts. Tests of a new technique in which the decelerator grid of a three-grid ion accelerator system is biased negative of neutralizer common potential in order to collect facility induced charge-exchange ions are described. These tests indicate that this SAND (Screen, Accelerator, Negative Decelerator) configuration may enable long duration ion engine endurance tests to be performed at vacuum chamber pressures an order of magnitude higher than previously possible. The corresponding reduction in pumping speed requirements enables endurance tests of 10 kW class ion engines to be performed within the resources of existing technology programs. The results of a successful 5,000-hr endurance of a xenon hollow cathode operating at an emission current of 25 A are described, as well as the initial tests of hollow cathodes operating on a mixture of argon and 3 percent nitrogen. Work performed on the development of carbon/carbon grids, a multi-orifice hollow cathode, and discharge chamber erosion reduction through the addition of nitrogen are also described. Critical applied-field MPD thruster technical issues remain to be resolved, including demonstration of reliable steady-state operation at input powers of hundreds to thousands of

  16. The Liquid Annular Reactor System (LARS) propulsion

    International Nuclear Information System (INIS)

    Powell, J.; Ludewig, H.; Horn, F.; Lenard, R.

    1990-01-01

    A concept for very high specific impulse (greater than 2000 seconds) direct nuclear propulsion is described. The concept, termed the liquid annular reactor system (LARS), uses liquid nuclear fuel elements to heat hydrogen propellant to very high temperatures (approximately 6000 K). Operating pressure is moderate (approximately 10 atm), with the result that the outlet hydrogen is virtually 100 percent dissociated to monatomic H. The molten fuel is contained in a solid container of its own material, which is rotated to stabilize the liquid layer by centripetal force. LARS reactor designs are described, together with neutronic and thermal-hydraulic analyses. Power levels are on the order of 200 megawatts. Typically, LARS designs use seven rotating fuel elements, are beryllium moderated, and have critical radii of approximately 100 cm (core L/D approximately equal to 1.5)

  17. Magnetohydrodynamic underwater vehicular propulsion systems

    International Nuclear Information System (INIS)

    Swallom, D.W.; Sadovnik, I.; Gibbs, J.S.; Gurol, H.; Nguyen, L.

    1990-01-01

    The development of magnetohydrodynamic propulsion systems for underwater vehicles is discussed. According to the authors, it is a high risk endeavor that offers the possibility of a number of significant advantages over conventional propeller propulsion systems. These advantages may include the potential for greater stealth characteristics, increased maneuverability, enhanced survivability, elimination of cavitation limits, and addition of a significant emergency propulsion system. The possibility of increased stealth is by far the most important advantage. A conceptual design study has been completed with numerical results that shows that these advantages may be obtained with a magnetohydrodynamic propulsion system in an annular configuration externally surrounding a generic study submarine that is neutrally buoyant and can operate with the existing submarine propulsion system power plant. The classical submarine mission requirements make the use of these characteristics of the magnetohydrodynamic propulsion system particularly appropriate for submarine missions. The magnetohydrodynamic annular propulsion system for a generic attack class submarine has been designed to take advantage of the magnetohydrodynamic thruster characteristics

  18. Fundamentals of aircraft and rocket propulsion

    CERN Document Server

    El-Sayed, Ahmed F

    2016-01-01

    This book provides a comprehensive basics-to-advanced course in an aero-thermal science vital to the design of engines for either type of craft. The text classifies engines powering aircraft and single/multi-stage rockets, and derives performance parameters for both from basic aerodynamics and thermodynamics laws. Each type of engine is analyzed for optimum performance goals, and mission-appropriate engines selection is explained. Fundamentals of Aircraft and Rocket Propulsion provides information about and analyses of: thermodynamic cycles of shaft engines (piston, turboprop, turboshaft and propfan); jet engines (pulsejet, pulse detonation engine, ramjet, scramjet, turbojet and turbofan); chemical and non-chemical rocket engines; conceptual design of modular rocket engines (combustor, nozzle and turbopumps); and conceptual design of different modules of aero-engines in their design and off-design state. Aimed at graduate and final-year undergraduate students, this textbook provides a thorough grounding in th...

  19. Advanced In-Space Propulsion (AISP): Micro Electrospray Propulsion (MEP)

    Data.gov (United States)

    National Aeronautics and Space Administration — Propulsion technology is often critical for space missions. High-value missions could be done with very small spacecraft, even CubeSats, but these nanosatellites...

  20. Pulse Generator

    Science.gov (United States)

    Greer, Lawrence (Inventor)

    2017-01-01

    An apparatus and a computer-implemented method for generating pulses synchronized to a rising edge of a tachometer signal from rotating machinery are disclosed. For example, in one embodiment, a pulse state machine may be configured to generate a plurality of pulses, and a period state machine may be configured to determine a period for each of the plurality of pulses.

  1. Advanced Propulsion Study

    Science.gov (United States)

    2004-02-01

    and solar cells . A conventional (expendable or reusable) rocket or gun launches a payload into space and into the funnel, which guides the payload...pulsed “Driver” infrared CO2 laser, now stored in Test Cell #2 at HELSTF. Preparations are underway to utilize this laser, which was developed at...Visser (1995), derived a spacetime metric that generates a traversable wormhole (or hyperspace tunnel) geometry in spacetime. This unique geometry

  2. Boron-proton nuclear-fusion enhancement induced in boron-doped silicon targets by low-contrast pulsed laser

    Czech Academy of Sciences Publication Activity Database

    Picciotto, A.; Margarone, Daniele; Velyhan, Andriy; Bellutti, P.; Krása, Josef; Szydlowsky, A.; Bertuccio, G.; Shi, Y.; Mangione, A.; Prokůpek, Jan; Malinowska, A.; Krouský, Eduard; Ullschmied, Jiří; Láska, Leoš; Kucharik, M.; Korn, Georg

    2014-01-01

    Roč. 4, č. 3 (2014), , "031030-1"-"031030-8" ISSN 2160-3308 R&D Projects: GA MŠk ED1.1.00/02.0061; GA MŠk(CZ) LD14089; GA MŠk LM2010014 EU Projects: European Commission(XE) 284464 - LASERLAB-EUROPE Grant - others:ELI Beamlines(XE) CZ.1.05/1.1.00/02.0061; AVČR(CZ) M100101210 Institutional support: RVO:68378271 ; RVO:61389021 Keywords : thermonuclear fusion * fast ions * plasmas * energy * acceleration * hydrogen * detector Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders; BL - Plasma and Gas Discharge Physics (UFP-V) Impact factor: 9.043, year: 2014

  3. Development of Cubesat Propulsion Systems

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall objective of this IRAD will be to develop a propulsion system that can be cheaply and reliably used for NASA GSFC cubesat missions. Reliability will be...

  4. Rotational propulsion enabled by inertia.

    Science.gov (United States)

    Nadal, François; Pak, On Shun; Zhu, LaiLai; Brandt, Luca; Lauga, Eric

    2014-07-01

    The fluid mechanics of small-scale locomotion has recently attracted considerable attention, due to its importance in cell motility and the design of artificial micro-swimmers for biomedical applications. Most studies on the topic consider the ideal limit of zero Reynolds number. In this paper, we investigate a simple propulsion mechanism --an up-down asymmetric dumbbell rotating about its axis of symmetry-- unable to propel in the absence of inertia in a Newtonian fluid. Inertial forces lead to continuous propulsion for all finite values of the Reynolds number. We study computationally its propulsive characteristics as well as analytically in the small-Reynolds-number limit. We also derive the optimal dumbbell geometry. The direction of propulsion enabled by inertia is opposite to that induced by viscoelasticity.

  5. Propulsion Systems Laboratory, Bldg. 125

    Data.gov (United States)

    Federal Laboratory Consortium — The Propulsion Systems Laboratory (PSL) is NASAs only ground test facility capable of providing true altitude and flight speed simulation for testing full scale gas...

  6. Self-diffusion of electrolyte species in model battery electrodes using Magic Angle Spinning and Pulsed Field Gradient Nuclear Magnetic Resonance

    Science.gov (United States)

    Tambio, Sacris Jeru; Deschamps, Michaël; Sarou-Kanian, Vincent; Etiemble, Aurélien; Douillard, Thierry; Maire, Eric; Lestriez, Bernard

    2017-09-01

    Lithium-ion batteries are electrochemical storage devices using the electrochemical activity of the lithium ion in relation to intercalation compounds owing to mass transport phenomena through diffusion. Diffusion of the lithium ion in the electrode pores has been poorly understood due to the lack of experimental techniques for measuring its self-diffusion coefficient in porous media. Magic-Angle Spinning, Pulsed Field Gradient, Stimulated-Echo Nuclear Magnetic Resonance (MAS-PFG-STE NMR) was used here for the first time to measure the self-diffusion coefficients of the electrolyte species in the LP30 battery electrolyte (i.e. a 1 M solution of LiPF6 dissolved in 1:1 Ethylene Carbonate - Dimethyl Carbonate) in model composites. These composite electrodes were made of alumina, carbon black and PVdF-HFP. Alumina's magnetic susceptibility is close to the measured magnetic susceptibility of the LP30 electrolyte thereby limiting undesirable internal field gradients. Interestingly, the self-diffusion coefficient of lithium ions decreases with increasing carbon content. FIB-SEM was used to describe the 3D geometry of the samples. The comparison between the reduction of self-diffusion coefficients as measured by PFG-NMR and as geometrically derived from FIB/SEM tortuosity values highlights the contribution of specific interactions at the material/electrolyte interface on the lithium transport properties.

  7. Building Of Training Program Of Non-Destructive Testing For Concrete Structures (Part 1: Radiographic testing; Ultrasonic pulse velocity measurement; Nuclear moisture-density gauge)

    International Nuclear Information System (INIS)

    Nguyen Le Son; Phan Chanh Vu; Pham The Hung; Vu Huy Thuc

    2007-01-01

    Non-destructive testing methods (NDT) have been identified as a strong candidate for remote sensing of concrete structures over recent years. This has accelerated the powerful development of the NDT techniques in Vietnam. Hence, there is an urgent need to promote the awareness of NDT methods which could give an improved estimate of the condition concrete. Building of training program of non-destructive testing for concrete structures is a necessary duty, in aiming to build a unified training program, possibly satisfying the requirements on training as well as researching. Under the framework of the basic VAEC project (CS/07/02-03), a training program for the first 03 NDT methods: 1. Radiographic testing; 2. Ultrasonic pulse velocity measurement; 3. Nuclear moisture- density gauge was prepared. The main products of this project include: 1. Set out 03 training notes for 03 methods; 2. Set out the practical exercises to train for 03 methods; 3. Editing a set of examination questions in aiming to familiarize with various questions in 03 trained methods; 4. Fabricating practical test specimens to demonstrate for 03 techniques. (author)

  8. NMR in pulsed magnetic field

    KAUST Repository

    Abou-Hamad, Edy

    2011-09-01

    Nuclear magnetic resonance (NMR) experiments in pulsed magnetic fields up to 30.4 T focused on 1H and 93Nb nuclei are reported. Here we discuss the advantage and limitation of pulsed field NMR and why this technique is able to become a promising research tool. © 2011 Elsevier Inc. All Rights Reserved.

  9. Microwave Thermal Propulsion

    Science.gov (United States)

    Parkin, Kevin L. G.; Lambot, Thomas

    2017-01-01

    We have conducted research in microwave thermal propulsion as part of the space exploration access technologies (SEAT) research program, a cooperative agreement (NNX09AF52A) between NASA and Carnegie Mellon University. The SEAT program commenced on the 19th of February 2009 and concluded on the 30th of September 2015. The DARPA/NASA Millimeter-wave Thermal Launch System (MTLS) project subsumed the SEAT program from May 2012 to March 2014 and one of us (Parkin) served as its principal investigator and chief engineer. The MTLS project had no final report of its own, so we have included the MTLS work in this report and incorporate its conclusions here. In the six years from 2009 until 2015 there has been significant progress in millimeter-wave thermal rocketry (a subset of microwave thermal rocketry), most of which has been made under the auspices of the SEAT and MTLS programs. This final report is intended for multiple audiences. For researchers, we present techniques that we have developed to simplify and quantify the performance of thermal rockets and their constituent technologies. For program managers, we detail the facilities that we have built and the outcomes of experiments that were conducted using them. We also include incomplete and unfruitful lines of research. For decision-makers, we introduce the millimeter-wave thermal rocket in historical context. Considering the economic significance of space launch, we present a brief but significant cost-benefit analysis, for the first time showing that there is a compelling economic case for replacing conventional rockets with millimeter-wave thermal rockets.

  10. Electric Propulsion Induced Secondary Mass Spectroscopy

    Science.gov (United States)

    Amini, Rashied; Landis, Geoffrey

    2012-01-01

    A document highlights a means to complement remote spectroscopy while also providing in situ surface samples without a landed system. Historically, most compositional analysis of small body surfaces has been done remotely by analyzing reflection or nuclear spectra. However, neither provides direct measurement that can unambiguously constrain the global surface composition and most importantly, the nature of trace composition and second-phase impurities. Recently, missions such as Deep Space 1 and Dawn have utilized electric propulsion (EP) accelerated, high-energy collimated beam of Xe+ ions to propel deep space missions to their target bodies. The energies of the Xe+ are sufficient to cause sputtering interactions, which eject material from the top microns of a targeted surface. Using a mass spectrometer, the sputtered material can be determined. The sputtering properties of EP exhaust can be used to determine detailed surface composition of atmosphereless bodies by electric propulsion induced secondary mass spectroscopy (EPI-SMS). EPI-SMS operation has three high-level requirements: EP system, mass spectrometer, and altitude of about 10 km. Approximately 1 keV Xe+ has been studied and proven to generate high sputtering yields in metallic substrates. Using these yields, first-order calculations predict that EPI-SMS will yield high signal-to-noise at altitudes greater than 10 km with both electrostatic and Hall thrusters.

  11. Commercial nuclear ships

    International Nuclear Information System (INIS)

    Poirier d'Ange d'Orsay, P.; Andrieu, J.L.

    1975-01-01

    Following discussion of the arguments in favour of nuclear merchant ships and development of nuclear ship propulsion, the rentability of nuclear ships is dealt with in a comparative study with conventional ships regarding fuel costs, investments and environmental impact. The structure and components of a nuclear ship are described, with emphasis on its safety equipment. The problem of insurance is examined, particularly in connection with the difficulty in applying insurance for liability due to the present uncertainties of the legal position at international level. French legislation does not solve the problem of visiting foreign nuclear ships. The risk concept at operational, design and construction stages is also discussed. Unresolved difficulties, especially concerning the construction of nuclear ships, uncertainties in competitivity analyses between conventional and nuclear propulsion, and implementation of specific and complete legislation on nuclear ships are also mentioned, particularly in the context of their visits to ports [fr

  12. Research Opportunities in Space Propulsion

    Science.gov (United States)

    Rodgers, Stephen L.

    2007-01-01

    Rocket propulsion determines the primary characteristics of any space vehicle; how fast and far it can go, its lifetime, and its capabilities. It is the primary factor in safety and reliability and the biggest cost driver. The extremes of heat and pressure produced by propulsion systems push the limits of materials used for manufacturing. Space travel is very unforgiving with little room for errors, and so many things can go wrong with these very complex systems. So we have to plan for failure and that makes it costly. But what is more exciting than the roar of a rocket blasting into space? By its nature the propulsion world is conservative. The stakes are so high at every launch, in terms of payload value or in human life, that to introduce new components to a working, qualified system is extremely difficult and costly. Every launch counts and no risks are tolerated, which leads to the space world's version of Catch-22:"You can't fly till you flown." The last big 'game changer' in propulsion was the use of liquid hydrogen as a fuel. No new breakthrough, low cost access to space system will be developed without new efficient propulsion systems. Because there is no large commercial market driving investment in propulsion, what propulsion research is done is sponsored by government funding agencies. A further difficulty in propulsion technology development is that there are so few new systems flying. There is little opportunity to evolve propulsion technologies and to update existing systems with results coming out of research as there is in, for example, the auto industry. The biggest hurdle to space exploration is getting off the ground. The launch phase will consume most of the energy required for any foreseeable space exploration mission. The fundamental physical energy requirements of escaping earth's gravity make it difficult. It takes 60,000 kJ to put a kilogram into an escape orbit. The vast majority (-97%) of the energy produced by a launch vehicle is used

  13. A Multidisciplinary Study of Pulse Detonation Engine Propulsion

    National Research Council Canada - National Science Library

    Santoro, Robert

    2003-01-01

    .... The multidisciplinary research effort brought together a team of leading researchers in the areas of the initiation and propagation of detonations, liquid hydrocarbon spray detonation, combustion...

  14. A comparison of potential electric propulsion systems for orbit transfer

    Science.gov (United States)

    Jones, R. M.

    1982-01-01

    Electric propulsion concepts are compared on the basis of trip time for the low earth orbit (LEO) to geosynchronous earth orbit (GEO) mission. Resistojet, arcjet, magnetoplasmadynamic (MPD), pulsed inductive, and ion engine thruster concepts are included. The optimum (minimum trip time) value of specific impulse is found to be dependent upon the specific mission and system being considered. As expected, the devices which can deliver good efficiency at low specific impulses promise the fastest trip times. The solution for trip time and propellant mass for the constant power, continuous low acceleration orbit transfer problem (one way and round trip) is presented in nomograph form. The influences of mission Delta V, thruster efficiency, specific impulse, power, power and propulsion system mass, and payload mass are clearly illustrated.

  15. Frontiers in propulsion research: Laser, matter-antimatter, excited helium, energy exchange thermonuclear fusion

    Science.gov (United States)

    Papailiou, D. D. (Editor)

    1975-01-01

    Concepts are described that presently appear to have the potential for propulsion applications in the post-1990 era of space technology. The studies are still in progress, and only the current status of investigation is presented. The topics for possible propulsion application are lasers, nuclear fusion, matter-antimatter annihilation, electronically excited helium, energy exchange through the interaction of various fields, laser propagation, and thermonuclear fusion technology.

  16. Hypothetical Dark Matter/axion Rockets:. Dark Matter in Terms of Space Physics Propulsion

    Science.gov (United States)

    Beckwith, A.

    2010-12-01

    Current proposed photon rocket designs include the Nuclear Photonic Rocket and the Antimatter Photonic Rocket (proposed by Eugen Sanger in the 1950s, as reported by Ref. 1). This paper examines the feasibility of improving the thrust of photon-driven ramjet propulsion by using DM rocket propulsion. The open question is: would a heavy WIMP, if converted to photons, upgrade the power (thrust) of a photon rocket drive, to make interstellar travel a feasible proposition?

  17. Propulsion on a superhydrophobic ratchet.

    Science.gov (United States)

    Dupeux, Guillaume; Bourrianne, Philippe; Magdelaine, Quentin; Clanet, Christophe; Quéré, David

    2014-06-13

    Liquids in the Leidenfrost state were shown by Linke to self-propel if placed on ratchets. The vapour flow below the liquid rectified by the asymmetric teeth entrains levitating drops by viscosity. This effect is observed above the Leidenfrost temperature of the substrate, typically 200°C for water. Here we show that coating ratchets with super-hydrophobic microtextures extends quick self-propulsion down to a substrate temperature of 100°C, which exploits the persistence of Leidenfrost state with such coatings. Surprisingly, propulsion is even observed below 100°C, implying that levitation is not necessary to induce the motion. Finally, we model the drop velocity in this novel "cold regime" of self-propulsion.

  18. Breakthrough Propulsion Physics Research Program

    Science.gov (United States)

    Millis, Marc G.

    1996-01-01

    In 1996, a team of government, university and industry researchers proposed a program to seek the ultimate breakthroughs in space transportation: propulsion that requires no propellant mass, propulsion that can approach and, if possible, circumvent light speed, and breakthrough methods of energy production to power such devices. This Breakthrough Propulsion Physics program, managed by Lewis Research Center, is one part of a comprehensive, long range Advanced Space Transportation Plan managed by Marshall Space Flight Center. Because the breakthrough goals are beyond existing science, a main emphasis of this program is to establish metrics and ground rules to produce near-term credible progress toward these incredible possibilities. An introduction to the emerging scientific possibilities from which such solutions can be sought is also presented.

  19. Main Propulsion Test Article (MPTA)

    Science.gov (United States)

    Snoddy, Cynthia

    2010-01-01

    Scope: The Main Propulsion Test Article integrated the main propulsion subsystem with the clustered Space Shuttle Main Engines, the External Tank and associated GSE. The test program consisted of cryogenic tanking tests and short- and long duration static firings including gimbaling and throttling. The test program was conducted on the S1-C test stand (Position B-2) at the National Space Technology Laboratories (NSTL)/Stennis Space Center. 3 tanking tests and 20 hot fire tests conducted between December 21 1 1977 and December 17, 1980 Configuration: The main propulsion test article consisted of the three space shuttle main engines, flightweight external tank, flightweight aft fuselage, interface section and a boilerplate mid/fwd fuselage truss structure.

  20. Magnetic levitation and MHD propulsion

    International Nuclear Information System (INIS)

    Tixador, P.

    1994-01-01

    Magnetic levitation and MHD propulsion are now attracting attention in several countries. Different superconducting MagLev and MHD systems will be described concentrating on, above all, the electromagnetic aspect. Some programmes occurring throughout the world will be described. Magnetic levitated trains could be the new high speed transportation system for the 21st century. Intensive studies involving MagLev trains using superconductivity have been carried our in Japan since 1970. The construction of a 43 km long track is to be the next step. In 1991 a six year programme was launched in the United States to evaluate the performances of MagLev systems for transportation. The MHD (MagnetoHydroDynamic) offers some interesting advantages (efficiency, stealth characteristics, ..) for naval propulsion and increasing attention is being paid towards it nowadays. Japan is also up at the top with the tests of Yamato I, a 260 ton MHD propulsed ship. (orig.)

  1. First Breakthrough for Future Air-Breathing Magneto-Plasma Propulsion Systems

    Science.gov (United States)

    Göksel, B.; Mashek, I. Ch

    2017-04-01

    A new breakthrough in jet propulsion technology since the invention of the jet engine is achieved. The first critical tests for future air-breathing magneto-plasma propulsion systems have been successfully completed. In this regard, it is also the first time that a pinching dense plasma focus discharge could be ignited at one atmosphere and driven in pulse mode using very fast, nanosecond electrostatic excitations to induce self-organized plasma channels for ignition of the propulsive main discharge. Depending on the capacitor voltage (200-600 V) the energy input at one atmosphere varies from 52-320 J/pulse corresponding to impulse bits from 1.2-8.0 mNs. Such a new pulsed plasma propulsion system driven with one thousand pulses per second would already have thrust-to-area ratios (50-150 kN/m²) of modern jet engines. An array of thrusters could enable future aircrafts and airships to start from ground and reach altitudes up to 50km and beyond. The needed high power could be provided by future compact plasma fusion reactors already in development by aerospace companies. The magneto-plasma compressor itself was originally developed by Russian scientists as plasma fusion device and was later miniaturized for supersonic flow control applications. So the first breakthrough is based on a spin-off plasma fusion technology.

  2. Physics of antimatter-matter reactions for interstellar propulsion

    International Nuclear Information System (INIS)

    Morgan, D.L. Jr.

    1986-01-01

    At the stage of the antiproton-nucleon annihilation chain of events relevant to propulsion the annihilation produces energetic charged pions and gamma rays. If annihilation occurs in a complex nucleus, protons, neutrons, and other nuclear fragments are also produced. The charge, number, and energy of the annihilation products are such that annihilation rocket engine concepts involving relatively low specific impulse (I/sub sp/ ≅ 1000 to 2000 s) and very high I/sub sp/ (3 x 10 7 s) appear feasible and have efficiencies on the order of 50% for annihilation energy to propulsion energy conversion. At I/sub sp/'s of around 15,000 s, however, it may be that only the kinetic energy of the charged nuclear fragments can be utilized for propulsion in engines of ordinary size. An estimate of this kinetic energy was made from known pieces of experimental and theoretical information. Its value is about 10% of the annihilation energy. Control over the mean penetration depth of protons into matter prior to annihilation is necessary so that annihilation occurs in the proper region within the engine. Control is possible by varying the antiproton kinetic energy to obtain a suitable annihilation cross section. The annihilation cross section at low energies is on the order of or larger than atomic areas due to a rearrangement reaction, but it is very low at high energy where its value is closer to nuclear areas

  3. PULSE GENERATOR

    Science.gov (United States)

    Roeschke, C.W.

    1957-09-24

    An improvement in pulse generators is described by which there are produced pulses of a duration from about 1 to 10 microseconds with a truly flat top and extremely rapid rise and fall. The pulses are produced by triggering from a separate input or by modifying the current to operate as a free-running pulse generator. In its broad aspect, the disclosed pulse generator comprises a first tube with an anode capacitor and grid circuit which controls the firing; a second tube series connected in the cathode circuit of the first tube such that discharge of the first tube places a voltage across it as the leading edge of the desired pulse; and an integrator circuit from the plate across the grid of the second tube to control the discharge time of the second tube, determining the pulse length.

  4. Simulation of Electric Propulsion Thrusters

    Science.gov (United States)

    2011-01-01

    pp. 764-773. [17] Boyd, I.D., “Monte Carlo Simulation of Nonequilibrium Flow in Low Power Hydrogen Arcjets ,” Physics of Fluids, Vol. 9, 1997, pp...Habiger, H., Hammer, F., Kurtz, H., Riehle, M., and Sleziona, C., “High- Power Hydrogen Arcjet Thrusters,” Journal of Propulsion and Power , Vol. 14, 1998...3086-3095. [18] Boyd, I.D., “Extensive Validation of a Monte Carlo Model for Hydrogen Arcjet Flow Fields,” Journal of Propulsion and Power , Vol. 13

  5. Antimatter Propulsion Developed by NASA

    Science.gov (United States)

    1999-01-01

    This Quick Time movie shows possible forms of an antimatter propulsion system being developed by NASA. Antimatter annihilation offers the highest possible physical energy density of any known reaction substance. It is about 10 billion times more powerful than that of chemical energy such as hydrogen and oxygen combustion. Antimatter would be the perfect rocket fuel, but the problem is that the basic component of antimatter, antiprotons, doesn't exist in nature and has to manufactured. The process of antimatter development is ongoing and making some strides, but production of this as a propulsion system is far into the future.

  6. Space Shuttle Main Propulsion System

    Science.gov (United States)

    Wood, C. C.

    1976-01-01

    The Space Shuttle Main Propulsion System provides the impulse to transfer the reusable Orbiter of the Space Shuttle Transportation system and its payload from earth to earth orbit. Both cryogenic and solid rocket propulsion systems are utilized. The selected systems are characterized by (1) reusability wherever possible to reduce program cost, (2) design pressures, and other important design parameters, for the liquid propellant engine significantly higher than past programs for increased performance, and (3) advanced materials and manufacturing processes to withstand the extreme environments. The approaches for solution of these varied problems are emphasized.

  7. Nuclear safety in France

    International Nuclear Information System (INIS)

    Servant, J.

    1979-12-01

    The main areas of nuclear safety are considered in this paper, recalling the laws and resolutions in force and also the appropriate authority in each case. The following topics are reviewed: radiological protection, protection of workers, measures to be taken in case of an accident, radioactive effluents, impact on the environment of non-nuclear pollution, nuclear plant safety, protection against malicious acts, control and safeguard of nuclear materials, radioisotopes, transport of radioactive substances, naval propulsion, waste management, nuclear plant decommissioning and export of nuclear equipment and materials. Finally, the author describes the role of the general Secretariat of the Interdepartmental Committee on Nuclear Safety

  8. Vacuum Chamber Construction and Contamination Study of A Micro Pulsed Plasma Thruster

    National Research Council Canada - National Science Library

    Debevec, Jacob H

    2006-01-01

    The micro pulsed plasma thruster (micro-PPT) is a simple and versatile electric thruster capable of performing multiple missions, from precise attitude control on standard satellites to primary propulsion for nanosatellites...

  9. A Green, Safe, Dual-pulse Solid Motor for CubeSat Orbit Changing, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Small satellites such as CubeSats are in need of responsive propulsion, but are limited due to their size. Though single pulse, AP/HTPB fueled solid rocket motors...

  10. Pulsed-laser capabilities at the Laser-Hardened Materials Evaluation Laboratory (LHMEL)

    Science.gov (United States)

    Royse, Robert W.; Seibert, Daniel B., II; Lander, Michael L.; Eric, John J.

    2000-08-01

    Pulsed laser capabilities at the Laser Hardened Material Evaluation Laboratory are described relevant to optical coupling, impulse generation and laser propulsion. Capabilities of the Nd:Glass laser are presented as well as supporting test systems.

  11. Millimicrosecond pulse techniques

    CERN Document Server

    Lewis, Ian A D

    1959-01-01

    Millimicrosecond Pulse Techniques, Second Edition focuses on millimicrosecond pulse techniques and the development of devices of large bandwidth, extending down to comparatively low frequencies (1 Mc/s). Emphasis is on basic circuit elements and pieces of equipment of universal application. Specific applications, mostly in the field of nuclear physics instrumentation, are considered. This book consists of eight chapters and opens with an introduction to some of the terminology employed by circuit engineers as well as theoretical concepts, including the laws of circuit analysis, Fourier analysi

  12. Information report presented in application of article 145 of the regulation by the commission of national defense and armed forces about the propulsion system of the second aircraft carrier; Rapport d'information depose en application de l'article 145 du reglement par la commission de la defense nationale et des forces armees sur le mode de propulsion du second porte-avions

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-11-01

    In the framework of the project of launching of a sister-ship to the Charles de Gaulle aircraft carrier, this report makes an objective analysis of the different possible propulsion systems that can be considered for this battle ship according to different criteria: 1 - two possible energy sources and four possible configurations of aircraft carrier considered: alternative between nuclear propulsion and conventional propulsion, the two nuclear ships eventualities, the hypothesis of an entirely French-made classical propulsion ship, the opportunity of a French-British cooperation for a conventional aircraft carrier project; 2 - decision criteria: operational need, cost, industrial and technological stakes, constraints linked with daily ship and crew life; 3 - propulsion systems alternative: conventional propulsion and reinforcement of the European defense policy, nuclear propulsion for an operational superiority and for a complementarity with the Charles de Gaulle. (J.S.)

  13. In vitro investigations of propulsion during laser lithotripsy using video tracking.

    Science.gov (United States)

    Eisel, Maximilian; Ströbl, Stephan; Pongratz, Thomas; Strittmatter, Frank; Sroka, Ronald

    2017-12-20

    Ureteroscopic laser lithotripsy is an important and widely used method for destroying ureter stones. It represents an alternative to ultrasonic and pneumatic lithotripsy techniques. Although these techniques have been thoroughly investigated, the influence of some physical parameters that may be relevant to further improve the treatment results is not fully understood. One crucial topic is the propulsive stone movement induced by the applied laser pulses. To simplify and speed up the optimization of laser parameters in this regard, a video tracking method was developed in connection with a vertical column setup that allows recording and subsequently analyzing the propulsive stone movement in dependence of different laser parameters in a particularly convenient and fast manner. Pulsed laser light was applied from below to a cubic BegoStone phantom loosely guided within a vertical column setup. The video tracking method uses an algorithm to determine the vertical stone position in each frame of the recorded scene. The time-dependence of the vertical stone position is characterized by an irregular series of peaks. By analyzing the slopes of the peaks in this signal it was possible to determine the mean upward stone velocity for a whole pulse train and to compare it for different laser settings. For a proof of principle of the video tracking method, a specific pulse energy setting (1 J/pulse) was used in combination with three different pulse durations: short pulse (0.3 ms), medium pulse (0.6 ms), and long pulse (1.0 ms). The three pulse durations were compared in terms of their influence on the propulsive stone movement in terms of upward velocity. Furthermore, the propulsions induced by two different pulse energy settings (0.8 J/pulse and 1.2 J/pulse) for a fixed pulse duration (0.3 ms) were compared. A pulse repetition rate of 10 Hz was chosen for all experiments, and for each laser setting, the experiment was repeated on 15 different freshly

  14. The ac propulsion system for an electric vehicle, phase 1

    Science.gov (United States)

    Geppert, S.

    1981-01-01

    A functional prototype of an electric vehicle ac propulsion system was built consisting of a 18.65 kW rated ac induction traction motor, pulse width modulated (PWM) transistorized inverter, two speed mechanically shifted automatic transmission, and an overall drive/vehicle controller. Design developmental steps, and test results of individual components and the complex system on an instrumented test frame are described. Computer models were developed for the inverter, motor and a representative vehicle. A preliminary reliability model and failure modes effects analysis are given.

  15. Aerospace propulsion using laser-driven plasma generator

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Daozhi (Beijing Univ. of Aeronautics and Astronautics (People' s Republic of China))

    1989-04-01

    The use of a remote pulsed laser beam for aerospace vehicle propulsion is suggested. The engine will be of variable cycle type using a plasma generator, and the vehicle will be of rotary plate type. It will be launched using an external radiated-heated VTOL thruster, lifted by an MHD fanjet, and accelerated by a rotary rocket pulsejet. It is speculated that, sending the same payload into low earth orbit, the vehicle mass at liftoff will be 1/20th that of the Space Shuttle, and the propellant mass carried by the new vehicle will be only 1/40th that of the Shuttle. 40 refs.

  16. Replacement of chemical rocket launchers by beamed energy propulsion.

    Science.gov (United States)

    Fukunari, Masafumi; Arnault, Anthony; Yamaguchi, Toshikazu; Komurasaki, Kimiya

    2014-11-01

    Microwave Rocket is a beamed energy propulsion system that is expected to reach space at drastically lower cost. This cost reduction is estimated by replacing the first-stage engine and solid rocket boosters of the Japanese H-IIB rocket with Microwave Rocket, using a recently developed thrust model in which thrust is generated through repetitively pulsed microwave detonation with a reed-valve air-breathing system. Results show that Microwave Rocket trajectory, in terms of velocity versus altitude, can be designed similarly to the current H-IIB first stage trajectory. Moreover, the payload ratio can be increased by 450%, resulting in launch-cost reduction of 74%.

  17. Numerical Investigation of Detonation Combustion Wave in Pulse Detonation Combustor with Ejector

    OpenAIRE

    P. Debnath; K. M. Pandey

    2017-01-01

    Detonation combustion based engines are more efficient compared to conventional deflagration based engines. Pulse detonation engine is the new concept in propulsion technology for future propulsion system. In this contrast, an ejector was used to modify the detonation wave propagation structure in pulse detonation engine combustor. In this paper k-ε turbulence model was used for detonation wave shock pattern simulation in PDE with ejectors at Ansys 14 Fluent platform. The unsteady Euler equat...

  18. Space technology needs nuclear power

    International Nuclear Information System (INIS)

    Leidinger, B.J.G.

    1993-01-01

    Space technology needs nuclear power to solve its future problems. Manned space flight to Mars is hardly feasible without nuclear propulsion, and orbital nuclear power lants will be necessary to supply power to large satellites or large space stations. Nuclear power also needs space technology. A nuclear power plant sited on the moon is not going to upset anybody, because of the high natural background radiation level existing there, and could contribute to terrestrial power supply. (orig./HP) [de

  19. Magnetic levitation and MHD propulsion

    Science.gov (United States)

    Tixador, P.

    1994-04-01

    Magnetic levitation and MHD propulsion are now attracting attention in several countries. Different superconducting MagLev and MHD systems will be described concentrating on, above all, the electromagnetic aspect. Some programmes occurring throughout the world will be described. Magnetic levitated trains could be the new high speed transportation system for the 21st century. Intensive studies involving MagLev trains using superconductivity have been carried out in Japan since 1970. The construction of a 43 km long track is to be the next step. In 1991 a six year programme was launched in the United States to evaluate the performances of MagLev systems for transportation. The MHD (MagnetoHydroDynamic) offers some interesting advantages (efficiency, stealth characteristics, ...) for naval propulsion and increasing attention is being paid towards it nowadays. Japan is also up at the top with the tests of Yamato I, a 260 ton MHD propulsed ship. Depuis quelques années nous assistons à un redémarrage de programmes concernant la lévitation et la propulsion supraconductrices. Différents systèmes supraconducteurs de lévitation et de propulsion seront décrits en examinant plus particulièrement l'aspect électromagnétique. Quelques programmes à travers le monde seront abordés. Les trains à sustentation magnétique pourraient constituer un nouveau mode de transport terrestre à vitesse élevée (500 km/h) pour le 21^e siècle. Les japonais n'ont cessé de s'intéresser à ce système avec bobine supraconductrice. Ils envisagent un stade préindustriel avec la construction d'une ligne de 43 km. En 1991 un programme américain pour une durée de six ans a été lancé pour évaluer les performances des systèmes à lévitation pour le transport aux Etats Unis. La MHD (Magnéto- Hydro-Dynamique) présente des avantages intéressants pour la propulsion navale et un regain d'intérêt apparaît à l'heure actuelle. Le japon se situe là encore à la pointe des d

  20. Transactions of the fourth symposium on space nuclear power systems

    Energy Technology Data Exchange (ETDEWEB)

    El-Genk, M.S.; Hoover, M.D. (eds.)

    1987-01-01

    This paper contains the presented papers at the fourth symposium on space nuclear power systems. Topics of these papers include: space nuclear missions and applications, reactors and shielding, nuclear electric and nuclear propulsion, refractory alloys and high-temperature materials, instrumentation and control, energy conversion and storage, space nuclear fuels, thermal management, nuclear safety, simulation and modeling, and multimegawatt system concepts. (LSP)

  1. Transactions of the fifth symposium on space nuclear power systems

    Energy Technology Data Exchange (ETDEWEB)

    El-Genk, M.S.; Hoover, M.D. (eds.)

    1988-01-01

    This paper contains the presented papers at the fourth symposium on space nuclear power systems. Topics of these paper include: space nuclear missions and applications, reactors and shielding, nuclear electric and nuclear propulsion, high-temperature materials, instrumentation and control, energy conversion and storage, space nuclear fuels, thermal management, nuclear safety, simulation and modeling, and multimegawatt system concepts. (LSP)

  2. Civilian application of propulsion reactor in Indonesia

    International Nuclear Information System (INIS)

    Djokolelono, M.; Arbie, B.; Lasman, A.N.

    2000-01-01

    It has been learned that to cope with energy requirement in the remote islands and less developed regions of Indonesia, small or very small nuclear reactors producing electricity and/or process heat could be appropriately applied. The barge mounted propulsion power reactors are the attractive examples so far envisioned, and technology information of which is being exposed to the world these last years. The solutions for least maintenance and no on-site refueling, no radioactive discharge, and no radioactive waste to remain in the user country are among the attractions for further deliberations. It has been understood, however, that there are many uncertainties to overcome, especially for the developing countries to introduce this novel application. International acceptance is the most crucial, availability of first-of-the-kind engineering, prototype or reference plant that would prove licensibility in the vendor's country is the second, and economic competitiveness due to very small size is the third among issues to enlighten. The relevant regulations concerning marine nuclear safety, marine transportation, and proliferation of information, as well as international forums to justify the feasibility of related transfer of technology, are the items that the IAEA could help to provide to smoothen any possible international transaction. Indonesia supports this AGM as one of the appropriate IAEA efforts in this line, and expects from it positive international consensus and possible studies/R and D work that this country could participate in. (author)

  3. Pulse Oximetry

    Science.gov (United States)

    ... American Thoracic Society www. thoracic. org American Thoracic Society PATIENT EDUCATION | INFORMATION SERIES How accurate is the pulse oximeter? The ... patient. co. uk/ doctor/ Pulse- Oximetry. htm This ... service of the American Thoracic Society. The content is for educational purposes only. It ...

  4. Using Additive Manufacturing to Print a CubeSat Propulsion System

    Science.gov (United States)

    Marshall, William M.

    2015-01-01

    CubeSats are increasingly being utilized for missions traditionally ascribed to larger satellites CubeSat unit (1U) defined as 10 cm x 10 cm x 11 cm. Have been built up to 6U sizes. CubeSats are typically built up from commercially available off-the-shelf components, but have limited capabilities. By using additive manufacturing, mission specific capabilities (such as propulsion), can be built into a system. This effort is part of STMD Small Satellite program Printing the Complete CubeSat. Interest in propulsion concepts for CubeSats is rapidly gaining interest-Numerous concepts exist for CubeSat scale propulsion concepts. The focus of this effort is how to incorporate into structure using additive manufacturing. End-use of propulsion system dictates which type of system to develop-Pulse-mode RCS would require different system than a delta-V orbital maneuvering system. Team chose an RCS system based on available propulsion systems and feasibility of printing using a materials extrusion process. Initially investigated a cold-gas propulsion system for RCS applications-Materials extrusion process did not permit adequate sealing of part to make this a functional approach.

  5. OTV propulsion tecnology programmatic overview

    Science.gov (United States)

    Cooper, L. P.

    1984-04-01

    An advanced orbit transfer vehicles (OTV) which will be an integral part of the national space transportation system to carry men and cargo between low Earth orbit and geosynchronous orbit will perform planetary transfers and deliver large acceleration limited space structures to high Earth orbits is reviewed. The establishment of an advanced propulsion technology base for an OTV for the mid 1990's is outlined. The program supports technology for three unique engine concepts. Work is conducted to generic technologies which benefit all three concepts and specific technology which benefits only one of the concepts. Concept and technology definitions to identify propulsion innovations, and subcomponent research to explore and validate their potential benefits are included.

  6. NASA's laser-propulsion project

    Science.gov (United States)

    Jones, L. W.; Keefer, D. R.

    1982-01-01

    Design concepts, study results, and research directions toward development of CW laser heating of remotely flying spacecraft fuels to provide high impulse thrust are presented. The incident laser radiation would be absorbed by hydrogen through a medium of a laser-supported plasma. The laser energy could be furnished from an orbiting solar-powered laser platform and used to drive the engines of an orbital transfer vehicle (OTV) at costs less than with a chemical propulsion system. The OTV propulsion chamber would be reduced in size comparable to the volume addition of the incident laser energy absorber. The temperatures in the hydrogen-fueled system could reach 5000-15,000 K, and studies have been done to examine the feasibility of ion-electron recombination. Kinetic performance, temperature field, and power necessary to sustain a laser thrust augmented system modeling results are discussed, along with near-term 30 kW CO2 laser system tests.

  7. Laser Diagnostics for Spacecraft Propulsion

    Science.gov (United States)

    MacDonald-Tenenbaum, Natalia

    2015-09-01

    Over the past several decades, a variety of laser diagnostic techniques have been developed and applied to diagnose spacecraft propulsion devices. Laser diagnostics are inherently non-intrusive, and provide the opportunity to probe properties such as temperature, concentration or number density of plume species, and plume velocities in the harsh environments of combustion and plasma discharges. This presentation provides an overview of laser diagnostic capabilities for spacecraft propulsion devices such as small monopropellant thrusters, arcjets, ion engines and Hall thrusters. Particular emphasis is placed on recent developments for time-resolved ion velocity measurements in Hall thruster plumes. Results are presented for one such diagnostic method, a time-synchronized CW-laser induced fluorescence (LIF) technique based on a sample hold scheme. This method is capable of correlating measured fluorescence excitation lineshapes with high frequency current fluctuations in the plasma discharge of a Hall thruster and is tolerant of natural drifting in the current oscillation frequency.

  8. Rocketdyne Propulsion & Power DOE Operations Annual Site Environmental Report 1996

    Energy Technology Data Exchange (ETDEWEB)

    Tuttle, R. J. [The Boeing Company, Canoga Park, CA (United States)

    1997-11-10

    This annual report discusses environmental monitoring at two manufacturing and test operations sites operated in the Los Angeles area by Rocketdyne Propulsion & Power of Boeing North American. Inc. (formerly Rockwell International Corporation). These are identified as the Santa Susana Field Laboratory (SSFL and the De Soto site. The sites have been used for manufacturing; R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The De Soto site essentially comprises office space and light industry with no remaining radiological operations, and has little potential impact on the environment. The SSFL site, because of its large size (2.668 acres), warrants comprehensive monitoring to ensure protection of the environment.

  9. Analysis of Electric Propulsion System for Exploration of Saturn

    Directory of Open Access Journals (Sweden)

    Carlos Renato Huaura Solórzano

    2009-01-01

    Full Text Available Exploration of the outer planets has experienced new interest with the launch of the Cassini and the New Horizons Missions. At the present time, new technologies are under study for the better use of electric propulsion system in deep space missions. In the present paper, the method of the transporting trajectory is used to study this problem. This approximated method for the flight optimization with power-limited low thrust is based on the linearization of the motion of a spacecraft near a keplerian orbit that is close to the transfer trajectory. With the goal of maximizing the mass to be delivered in Saturn, several transfers were studied using nuclear, radioisotopic and solar electric propulsion systems.

  10. Antimatter propulsion, status and prospects

    Science.gov (United States)

    Howe, Steven D.; Hynes, Michael V.

    1986-01-01

    The use of advanced propulsion techniques must be considered if the currently envisioned launch date of the manned Mars mission were delayed until 2020 or later. Within the next thirty years, technological advances may allow such methods as beaming power to the ship, inertial-confinement fusion, or mass-conversion of antiprotons to become feasible. A propulsion system with an ISP of around 5000 s would allow the currently envisioned mission module to fly to Mars in 3 months and would require about one million pounds to be assembled in Earth orbit. Of the possible methods to achieve this, the antiproton mass-conversion reaction offers the highest potential, the greatest problems, and the most fascination. Increasing the production rates of antiprotons is a high priority task at facilities around the world. The application of antiprotons to propulsion requires the coupling of the energy released in the mass-conversion reaction to thrust-producing mechanisms. Recent proposals entail using the antiprotons to produce inertial confinement fusion or to produce negative muons which can catalyze fusion. By increasing the energy released per antiproton, the effective cost, (dollars/joule) can be reduced. These proposals and other areas of research can be investigated now. These short term results will be important in assessing the long range feasibility of an antiproton powered engine.

  11. The electromagnetic pulse (EMP) as a danger for the world of electronics

    International Nuclear Information System (INIS)

    Horak, O.

    1984-01-01

    After discussing the characteristics and formation of a nuclear electromagnetic pulse, the author considers the effects such a pulse would have on various types of electronic systems. Finally he discusses what protection there is against such pulses. (Auth.)

  12. The NASA low thrust propulsion program

    Science.gov (United States)

    Stone, James R.; Bennett, Gary L.

    1989-01-01

    The NASA OAST Propulsion, Power, and Energy Division supports a low-thrust propulsion program aimed at providing high-performance options for a broad range of near-term and far-term missions and vehicles. Low-thrust propulsion has a major impact on the mission performance of essentially all spacecraft and vehicles. On-orbit lifetimes, payloads, and trip time are significantly impacted by low-thrust propulsion performance and integration features for earth-to-orbit (ETO) vehicles, earth-orbit and planetary spacecraft, and large platforms in earth orbit. Major emphases are on low-thrust chemical propulsion, both storables and hydrogen/oxygen; low-power (auxiliary) electric arcjets and resistojets; and high-power (primary) electric propulsion, including ion, magnetoplasmadynamic (MPD), and electrodeless concepts. The major recent accomplishments of the program are presented and their impacts discussed.

  13. Powered Flight The Engineering of Aerospace Propulsion

    CERN Document Server

    Greatrix, David R

    2012-01-01

    Whilst most contemporary books in the aerospace propulsion field are dedicated primarily to gas turbine engines, there is often little or no coverage of other propulsion systems and devices such as propeller and helicopter rotors or detailed attention to rocket engines. By taking a wider viewpoint, Powered Flight - The Engineering of Aerospace Propulsion aims to provide a broader context, allowing observations and comparisons to be made across systems that are overlooked by focusing on a single aspect alone. The physics and history of aerospace propulsion are built on step-by-step, coupled with the development of an appreciation for the mathematics involved in the science and engineering of propulsion. Combining the author’s experience as a researcher, an industry professional and a lecturer in graduate and undergraduate aerospace engineering, Powered Flight - The Engineering of Aerospace Propulsion covers its subject matter both theoretically and with an awareness of the practicalities of the industry. To ...

  14. In-Space Propulsion (ISP) Solar Sail Propulsion Technology Development

    Science.gov (United States)

    Montgomery, Edward E., IV

    2004-01-01

    An overview of the rationale and content for Solar Sail Propulsion (SSP), the on-going project to advance solar technology from technology readiness level 3 to 6 will be provided. A descriptive summary of the major and minor component efforts underway will include identification of the technology providers and a listing of anticipated products Recent important results from major system ground demonstrators will be provided. Finally, a current status of all activities will provided along with the most recent roadmap for the SSP technology development program.

  15. Civilian nuclear ships

    International Nuclear Information System (INIS)

    Oelgaard, P.L.

    1993-03-01

    This report contains a review of the information available on nuclear powered ships, built for civilian purposes. In the introduction a short discussion is given of the reasons for the limited use of nuclear ships for these purposes. In the second section a brief review is presented of data for the three experimental/merchant ships build by the United States, Germany and Japan, i.e. NS Savannah, NS Otto Hahn and NS Mutsu. In the third section the Soviet/Russian icebreaker NS Lenin is considered. Its design, operational experience and the introduction of a new nuclear propulsion plant is reviewed. In the fourth section the newer Soviet/Russian icebreakers with nuclear propulsion are considered. Finally design of the Soviet/Russian icebreaker transport/container ship NS Sevmorput is reviewed in the fifth section. The future Russian plans for nuclear vessels for the arctic waters are briefly discussed. (au)

  16. Development of the double-pulse technique to improve the analytical performance of Laser Induced Breakdown Spectroscopy (LIBS) on solids: Nuclear and geological applications

    International Nuclear Information System (INIS)

    Gautier, C.

    2005-10-01

    The double-pulse technique has been developed to improve the analytical performance of Laser Ablation coupled to Optical Emission Spectroscopy (LA/OES). This approach relies on the addition of a second time-resolved laser pulse to the classical LA/OES system. It has been studied on aluminium alloys according to different geometries of the two laser beams (orthogonal and collinear geometries) before being applied to different materials (synthetic glass, rock, steel, sodium chloride). The increase in emission intensity depends on the temporal parameters, on the excitation energy level of the emission line, on the concentration of the studied element and on the analyzed matrix. The double-pulse LA/OES technique can be particularly interesting to improve the sensitivity towards vitreous matrices containing elements emitting lines with high excitation energy levels. (author)

  17. Propulsion of liposomes using bacterial motors

    International Nuclear Information System (INIS)

    Zhang Zhenhai; Li Kejie; Li Zhifei; Yu Wei; Xie Zhihong; Shi Zhiguo

    2013-01-01

    Here we describe the utilization of flagellated bacteria as actuators to propel spherical liposomes by attaching bacteria to the liposome surface. Bacteria were stably attached to liposomes using a cross-linking antibody. The effect of the number of attached bacteria on propulsion speed was experimentally determined. The effects of bacterial propulsion on the bacteria–antibody–liposome complex were stochastic. We demonstrated that liposomal mobility increased when bacteria were attached, and the propulsion speed correlated with the number of bacteria. (paper)

  18. A Conceptual Tree of Laser Propulsion

    International Nuclear Information System (INIS)

    Pakhomov, Andrew V.; Sinko, John E.

    2008-01-01

    An original attempt to develop a conceptual tree for laser propulsion is offered. The tree provides a systematic view for practically all possible laser propulsion concepts and all inter-conceptual links, based on propellant phases and phase transfers. It also helps to see which fields of laser propulsion have been already thoroughly explored, where the next effort must be applied, and which paths should be taken with proper care or avoided entirely

  19. Explosive Nucleosynthesis Study Using Laser Driven γ-ray Pulses

    Directory of Open Access Journals (Sweden)

    Takehito Hayakawa

    2017-03-01

    Full Text Available We propose nuclear experiments using γ-ray pulses provided from high field plasma generated by high peak power laser. These γ-ray pulses have the excellent features of extremely short pulse, high intensity, and continuous energy distribution. These features are suitable for the study of explosive nucleosyntheses in novae and supernovae, such as the γ process and ν process. We discuss how to generate suitable γ-ray pulses and the nuclear astrophysics involved.

  20. An improved thermionic power conversion system for space propulsion

    Science.gov (United States)

    Hsieh, T. M.; Phillips, W. M.

    1978-01-01

    A concept of an out-of-core thermionic nuclear electric power conversion system for 400 Kwe power level is being investigated for space propulsion applications. Two key features distinguish the power system design from previous thermionic power conversion concepts. First, the thermionic converters are located outside a nuclear reactor with a neutron shield inserted to reduce the radiation level on the thermionic converter matrix. Second, multiple liquid-metal heat pipes are used exclusively for both thermal power transport (from the nuclear reactor to the thermionic converters) and waste heat removal (from the thermionic converters to the space radiator); no mechanical or electromagnetic pumps are involved. The system characteristics are are compared to those of the in-core thermionic reactor system concept. In many aspects, the system characteristics, including specific weight, lifetime, dynamics control and safety features are found to be more desirable than those of the in-core system concept.

  1. Electrospray Propulsion Engineering Toolkit (ESPET), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — To accelerate the development of scaled-up Electrospray Propulsion emitter array systems with practical thrust levels, Spectral Sciences, Inc. (SSI), in...

  2. Aeroelastic Wing Shaping Using Distributed Propulsion

    Science.gov (United States)

    Nguyen, Nhan T. (Inventor); Reynolds, Kevin Wayne (Inventor); Ting, Eric B. (Inventor)

    2017-01-01

    An aircraft has wings configured to twist during flight. Inboard and outboard propulsion devices, such as turbofans or other propulsors, are connected to each wing, and are spaced along the wing span. A flight controller independently controls thrust of the inboard and outboard propulsion devices to significantly change flight dynamics, including changing thrust of outboard propulsion devices to twist the wing, and to differentially apply thrust on each wing to change yaw and other aspects of the aircraft during various stages of a flight mission. One or more generators can be positioned upon the wing to provide power for propulsion devices on the same wing, and on an opposite wing.

  3. Propulsion Design with Freeform Fabrication, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Propulsion Design with Freeform Fabrication (PDFF) will develop and implement a novel design methodology that leverages the rapidly evolving Solid Freeform...

  4. Magnetically pulsed crystal monochromators on a pulsed neutron source

    International Nuclear Information System (INIS)

    Cywinski, R.

    1985-01-01

    For some crystal neutron monochromators a Bragg reflection can be found for which the structure factor for nuclear scattering is negligible, while that for magnetic scattering is large. Manipulation of the direction of the magnetisation within the crystal with respect to the scattering vector thus enables the reflectivity of the crystal to be switched on or off. On a pulsed neutron source such switching can be phased to the neutron pulse from the moderator, the duration of the magnetic ''on'' pulse defining the resolution of the monochromating device, and its exact phasing defining, within limits, the monochromated energy. This paper examines the principles of magnetically pulsed monochromation on a pulsed neutron source, and considers the performance of certain magnetic ferrites as pulsed monochromators. Comparisons are made between an inelastic scattering spectrometer based on ferrite monochromation and spectrometers using conventional (copper) crystal monochromators and choppers. It is shown that ferrite monochromation provides a comparible neutron flux at a given energy and resolution, with the additional flexibility that electronic control of the resolution permits an instantaneous balance to be made between resolution and neutron flux. It is also shown that magnetically pulsed monochromator techniques are well suited to crosscorrelation spectroscopy on pulsed neutron sources. (orig.)

  5. Diverse expansion of electric propulsion

    OpenAIRE

    Kuninaka, Hitoshi; 國中 均

    2007-01-01

    The microwave discharge ion engine mu 10 has long life and high reliability because of electrode-less plasma generation in both the ion generator and the neutralizer. Four mu 10s, each generating a thrust of 8 mN, propelled Hayabusa explorer to asteroid Itokawa. Electric propulsions including DC arcjets, MPD (Magneto Plasma Dynamic) arcjets, Hall thrusters as well as ion engines generate jets much faster than those of chemical rockets and make spacecraft fly by power in deep space so as to re...

  6. Propulsion at low Reynolds number

    Energy Technology Data Exchange (ETDEWEB)

    Najafi, Ali [Institute for Advanced Studies in Basic Sciences, Zanjan 45195-159 (Iran, Islamic Republic of); Faculty of Science, Zanjan University, Zanjan 313 (Iran, Islamic Republic of); Golestanian, Ramin [Institute for Advanced Studies in Basic Sciences, Zanjan 45195-159 (Iran, Islamic Republic of)

    2005-04-13

    We study the propulsion of two model swimmers at low Reynolds number. Inspired by Purcell's model, we propose a very simple one-dimensional swimmer consisting of three spheres that are connected by two arms whose lengths can change between two values. The proposed swimmer can swim with a special type of motion, which breaks the time-reversal symmetry. We also show that an ellipsoidal membrane with tangential travelling wave on it can also propel itself in the direction preferred by the travelling wave. This system resembles the realistic biological animals like Paramecium.

  7. Propulsion at low Reynolds number

    International Nuclear Information System (INIS)

    Najafi, Ali; Golestanian, Ramin

    2005-01-01

    We study the propulsion of two model swimmers at low Reynolds number. Inspired by Purcell's model, we propose a very simple one-dimensional swimmer consisting of three spheres that are connected by two arms whose lengths can change between two values. The proposed swimmer can swim with a special type of motion, which breaks the time-reversal symmetry. We also show that an ellipsoidal membrane with tangential travelling wave on it can also propel itself in the direction preferred by the travelling wave. This system resembles the realistic biological animals like Paramecium

  8. Low power pulsed MPD thruster system analysis and applications

    Science.gov (United States)

    Myers, Roger M.; Domonkos, Matthew; Gilland, James H.

    1993-01-01

    Pulsed magnetoplasmadynamic (MPD) thruster systems were analyzed for application to solar-electric orbit transfer vehicles at power levels ranging from 10 to 40 kW. Potential system level benefits of pulsed propulsion technology include ease of power scaling without thruster performance changes, improved transportability from low power flight experiments to operational systems, and reduced ground qualification costs. Required pulsed propulsion system components include a pulsed applied-field MPD thruster, a pulse-forming network, a charge control unit, a cathode heater supply, and high speed valves. Mass estimates were obtained for each propulsion subsystem and spacecraft component using off-the-shelf technology whenever possible. Results indicate that for payloads of 1000 and 2000 kg pulsed MPD thrusters can reduce launch mass by between 1000 and 2500 kg over those achievable with hydrogen arcjets, which can be used to reduce launch vehicle class and the associated launch cost. While the achievable mass savings depends on the trip time allowed for the mission, cases are shown in which the launch vehicle required for a mission is decreased from an Atlas IIAS to an Atlas I or Delta 7920.

  9. Electric Propulsion System Modeling for the Proposed Prometheus 1 Mission

    Science.gov (United States)

    Fiehler, Douglas; Dougherty, Ryan; Manzella, David

    2005-01-01

    The proposed Prometheus 1 spacecraft would utilize nuclear electric propulsion to propel the spacecraft to its ultimate destination where it would perform its primary mission. As part of the Prometheus 1 Phase A studies, system models were developed for each of the spacecraft subsystems that were integrated into one overarching system model. The Electric Propulsion System (EPS) model was developed using data from the Prometheus 1 electric propulsion technology development efforts. This EPS model was then used to provide both performance and mass information to the Prometheus 1 system model for total system trades. Development of the EPS model is described, detailing both the performance calculations as well as its evolution over the course of Phase A through three technical baselines. Model outputs are also presented, detailing the performance of the model and its direct relationship to the Prometheus 1 technology development efforts. These EP system model outputs are also analyzed chronologically showing the response of the model development to the four technical baselines during Prometheus 1 Phase A.

  10. Feasibility of MHD submarine propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Doss, E.D. (ed.) (Argonne National Lab., IL (United States)); Sikes, W.C. (ed.) (Newport News Shipbuilding and Dry Dock Co., VA (United States))

    1992-09-01

    This report describes the work performed during Phase 1 and Phase 2 of the collaborative research program established between Argonne National Laboratory (ANL) and Newport News Shipbuilding and Dry Dock Company (NNS). Phase I of the program focused on the development of computer models for Magnetohydrodynamic (MHD) propulsion. Phase 2 focused on the experimental validation of the thruster performance models and the identification, through testing, of any phenomena which may impact the attractiveness of this propulsion system for shipboard applications. The report discusses in detail the work performed in Phase 2 of the program. In Phase 2, a two Tesla test facility was designed, built, and operated. The facility test loop, its components, and their design are presented. The test matrix and its rationale are discussed. Representative experimental results of the test program are presented, and are compared to computer model predictions. In general, the results of the tests and their comparison with the predictions indicate that thephenomena affecting the performance of MHD seawater thrusters are well understood and can be accurately predicted with the developed thruster computer models.

  11. Pulse plating

    CERN Document Server

    Hansal, Wolfgang E G; Green, Todd; Leisner, Peter; Reichenbach, Andreas

    2012-01-01

    The electrodeposition of metals using pulsed current has achieved practical importance in recent years. Although it has long been known that changes in potential, with or without polarity reversal, can significantly affect the deposition process, the practical application of this has been slow to be adopted. This can largely be explained in terms of the complex relationship between the current regime and its effect on the electrodeposition process. In order to harness these effects, an understanding of the anodic and cathodic electrochemical processes is necessary, together with the effects of polarity reversal and the rate of such reversals. In this new monograph, the basics of metal electrodeposition from solution are laid out in great detail in seven distinct chapters. With this knowledge, the reader is able to predict how a given pulse train profile can be adopted to achieve a desired outcome. Equally important is the choice of a suitable rectifier and the ancillary control circuits to enable pulse platin...

  12. Damage-Tolerant, Lightweight, High-Temperature Radiator for Nuclear Powered Spacecraft

    Data.gov (United States)

    National Aeronautics and Space Administration — Game-changing propulsion systems are often enabled by novel designs using advanced materials. Radiator performance dictates power output for nuclear electric...

  13. High Thrust & High ISP Nuclear Thermal Rocket (NTR) Grooved Ring Fuel Element (GRFE)

    Data.gov (United States)

    National Aeronautics and Space Administration — Missions to Mars will benefit from propulsion systems with performance levels exceeding that of today's best chemical engines. Nuclear Thermal Rocket (NTR)...

  14. Mission to Mars using integrated propulsion concepts: considerations, opportunities, and strategies.

    Science.gov (United States)

    Accettura, Antonio G; Bruno, Claudio; Casotto, Stefano; Marzari, Francesco

    2004-04-01

    The aim of this paper is to evaluate the feasibility of a mission to Mars using the Integrated Propulsion Systems (IPS) which means to couple Nuclear-MPD-ISPU propulsion systems. In particular both mission analysis and propulsion aspects are analyzed together with technological aspects. Identifying possible mission scenarios will lead to the study of possible strategies for Mars Exploration and also of methods for reducing cost. As regard to IPS, the coupling between Nuclear Propulsion (Rubbia's engine) and Superconductive MPD propulsion is considered for the Earth-Mars trajectories: major emphasis is given to the advantages of such a system. The In Situ Resource Utilization (ISRU) concerns on-Mars operations; In Situ Propellant Utilization (ISPU) is foreseen particularly for LOX-CH4 engines for Mars Ascent Vehicles and this possibility is analyzed from a technological point of view. Tether Systems are also considered during interplanetary trajectories and as space elevators on Mars orbit. Finally strategic considerations associated to this mission are considered also. c2003 Elsevier Ltd. All rights reserved.

  15. Fluorine-Hydrazine Propulsion Technology update

    Science.gov (United States)

    Bond, D. L.; Appel, M. A.; Kruger, G. W.

    1980-01-01

    The current status of the fluorine hydrazine propulsion system development is discussed. Progress on the components, rocket engine, and system design is presented. A detailed look at a fluorine hydrazine system as a potential propulsion option for the Galileo Project (Jupiter orbiter) is delineated and the results of safety and technical reviews which were accomplished to verify the feasibility of this option are summarized.

  16. 46 CFR 109.555 - Propulsion boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Propulsion boilers. 109.555 Section 109.555 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Miscellaneous § 109.555 Propulsion boilers. The master or person in charge and the engineer in charge shall...

  17. 46 CFR 130.120 - Propulsion control.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Propulsion control. 130.120 Section 130.120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS VESSEL CONTROL, AND MISCELLANEOUS EQUIPMENT AND SYSTEMS Vessel Control § 130.120 Propulsion control. (a) Each vessel must have— (1...

  18. Propulsive force in front crawl swimming

    NARCIS (Netherlands)

    Berger, M.A.M.; de Groot, G.; Hollander, A.P.

    1999-01-01

    To evaluate the propulsive forces in front crawl arm swimming, derived from a three-dimensional kinematic analysis, these values were compared with mean drag forces. The propulsive forces during front crawl swimming using the arms only were calculated using three-dimensional kinematic analysis

  19. Observation of pulsed neutron Ramsey resonance

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Y. [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba Ibaraki 305-0801 (Japan)]. E-mail: yasuhiro.masuda@kek.jp; Skoy, V. [Joint Institute for Nuclear Reasearch, 141980 Dubna, Moscow Region (Russian Federation); Ino, T. [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba Ibaraki 305-0801 (Japan); Jeong, S.C. [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba Ibaraki 305-0801 (Japan); Watanabe, Y. [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba Ibaraki 305-0801 (Japan)

    2007-07-15

    A Ramsey resonance for pulsed neutrons was observed. The separated oscillatory fields for nuclear magnetic resonance were synchronized with a neutron pulse, and then the Ramsey resonance was observed as a function of the neutron velocity. The phase of one of the oscillatory fields was modulated as a function of the neutron time of flight for a neutron velocity measurement.

  20. Simulation Propulsion System and Trajectory Optimization

    Science.gov (United States)

    Hendricks, Eric S.; Falck, Robert D.; Gray, Justin S.

    2017-01-01

    A number of new aircraft concepts have recently been proposed which tightly couple the propulsion system design and operation with the overall vehicle design and performance characteristics. These concepts include propulsion technology such as boundary layer ingestion, hybrid electric propulsion systems, distributed propulsion systems and variable cycle engines. Initial studies examining these concepts have typically used a traditional decoupled approach to aircraft design where the aerodynamics and propulsion designs are done a-priori and tabular data is used to provide inexpensive look ups to the trajectory ana-ysis. However the cost of generating the tabular data begins to grow exponentially when newer aircraft concepts require consideration of additional operational parameters such as multiple throttle settings, angle-of-attack effects on the propulsion system, or propulsion throttle setting effects on aerodynamics. This paper proposes a new modeling approach that eliminated the need to generate tabular data, instead allowing an expensive propulsion or aerodynamic analysis to be directly integrated into the trajectory analysis model and the entire design problem optimized in a fully coupled manner. The new method is demonstrated by implementing a canonical optimal control problem, the F-4 minimum time-to-climb trajectory optimization using three relatively new analysis tools: Open M-DAO, PyCycle and Pointer. Pycycle and Pointer both provide analytic derivatives and Open MDAO enables the two tools to be combined into a coupled model that can be run in an efficient parallel manner that helps to cost the increased cost of the more expensive propulsion analysis. Results generated with this model serve as a validation of the tightly coupled design method and guide future studies to examine aircraft concepts with more complex operational dependencies for the aerodynamic and propulsion models.

  1. Propulsion system ignition overpressure for the Space Shuttle

    Science.gov (United States)

    Ryan, R. S.; Jones, J. H.; Guest, S. H.; Struck, H. G.; Rheinfurth, M. H.; Verferaime, V. S.

    1981-01-01

    Liquid and solid rocket motor propulsion systems create an overpressure wave during ignition, caused by the accelerating gas particles pushing against or displacing the air contained in the launch pad or launch facility and by the afterburning of the fuel-rich gases. This wave behaves as a blast or shock wave characterized by a positive triangular-shaped first pulse and a negative half-sine wave second pulse. The pulse travels up the space vehicle and has the potential of either overloading individual elements or exciting overall vehicle dynamics. The latter effect results from the phasing difference of the wave from one side of the vehicle to the other. This overpressure phasing, or delta P environment, because of its frequency content as well as amplitude, becomes a design driver for certain panels (e.g., thermal shields) and payloads for the Space Shuttle. The history of overpressure effects on the Space Shuttle, the basic overpressure phenomenon, Space Shuttle overpressure environment, scale model overpressure testing, and techniques for suppressing the overpressure environments are considered.

  2. Quantitative pulsed eddy current analysis

    International Nuclear Information System (INIS)

    Morris, R.A.

    1975-01-01

    The potential of pulsed eddy current testing for furnishing more information than conventional single-frequency eddy current methods has been known for some time. However, a fundamental problem has been analyzing the pulse shape with sufficient precision to produce accurate quantitative results. Accordingly, the primary goal of this investigation was to: demonstrate ways of digitizing the short pulses encountered in PEC testing, and to develop empirical analysis techniques that would predict some of the parameters (e.g., depth) of simple types of defect. This report describes a digitizing technique using a computer and either a conventional nuclear ADC or a fast transient analyzer; the computer software used to collect and analyze pulses; and some of the results obtained. (U.S.)

  3. Numerical simulation of a nonlinear coupled fluid-structure problem. Application to the design of naval nuclear propulsion structures; Modelisation et simulation numerique d'un probleme couple fluide/structure non lineaire: application au dimensionnement de structures nucleaires de propulsion navale

    Energy Technology Data Exchange (ETDEWEB)

    Sigrist, J.F

    2004-11-15

    application of the finite element coupling techniques is exposed. A modal analysis is performed on a simplified model of a nuclear reactor; this example highlights the importance of fluid/structure effects in the industrial case. (author)

  4. Completely modular Thermionic Reactor Ion Propulsion System (TRIPS)

    Science.gov (United States)

    Peelgren, M. L.; Kikin, G. M.; Sawyer, C. D.

    1972-01-01

    The nuclear reactor powered ion propulsion system described is an advanced completely modularized system which lends itself to development of prototype and/or flight type components without the need for complete system tests until late in the development program. This modularity is achieved in all of the subsystems and components of the electric propulsion system including (1) the thermionic fuel elements, (2) the heat rejection subsystem (heat pipes), (3) the power conditioning modules, and (4) the ion thrusters. Both flashlight and external fuel type in-core thermionic reactors are considered as the power source. The thermionic fuel elements would be useful over a range of reactor power levels. Electrical heated acceptance testing in their flight configuration is possible for the external fuel case. Nuclear heated testing by sampling methods could be used for acceptance testing of flashlight fuel elements. The use of heat pipes for cooling the collectors and as a means of heat transport to the radiator allows early prototype or flight configuration testing of a small module of the heat rejection subsystem as opposed to full scale liquid metal pumps and radiators in a large vacuum chamber. The power conditioner (p/c) is arranged in modules with passive cooling.

  5. Comparison of Propulsion Options for Human Exploration of Mars

    Science.gov (United States)

    Drake, Bret G.; McGuire, Melissa L.; McCarty, Steven L.

    2018-01-01

    NASA continues to advance plans to extend human presence beyond low-Earth orbit leading to human exploration of Mars. The plans being laid out follow an incremental path, beginning with initial flight tests followed by deployment of a Deep Space Gateway (DSG) in cislunar space. This Gateway, will serve as the initial transportation node for departing and returning Mars spacecraft. Human exploration of Mars represents the next leap for humankind because it will require leaving Earth on a long mission with very limited return, rescue, or resupply capabilities. Although Mars missions are long, approaches and technologies are desired which can reduce the time that the crew is away from Earth. This paper builds off past analyses of NASA's exploration strategy by providing more detail on the performance of alternative in-space transportation options with an emphasis on reducing total mission duration. Key options discussed include advanced chemical, nuclear thermal, nuclear electric, solar electric, as well as an emerging hybrid propulsion system which utilizes a combination of both solar electric and chemical propulsion.

  6. Propulsion of a microsubmarine using a thermally oscillatory approach

    Science.gov (United States)

    Qiao, Lei; Luo, Cheng

    2013-10-01

    In this paper, motivated by the driving mechanism of a putt-putt toy boat, we explore the feasibility to propel a microsubmarine using a thermally oscillatory approach, which only requires a simple design and does not involve any complicated propulsive systems. We investigate the design, fabrication, actuation and horizontal motions of the corresponding microsubmarines. Based on the understanding gained through preliminary tests on two manually fabricated putt-putt boats, we designed and fabricated the prototype of a microsubmarine. Similar to a putt-putt boat, the prototype also uses a thermally oscillatory process for propulsion. In a cyclic period of this process, due to the expansion and shrinkage of a vapor bubble inside the reservoir of the submarine, liquid is first ejected outside and then sucked into the reservoir. Due to the difference in liquid flow directions between ejection and suction stages, a thrust is produced to propel the submarine. At an applied voltage of 16 V and pulse frequency of 100 Hz, the submarine was found to have the highest speed of 1.8 mm s-1 and longest travel distance of 12.6 mm. The corresponding thrust was estimated to be 67.6 nN.

  7. Laser propulsion to earth orbit. Has its time come?

    Science.gov (United States)

    Kantrowitz, Arthur

    1989-01-01

    Recent developments in high energy lasers, adaptive optics, and atmospheric transmission bring laser propulsion much closer to realization. Proposed here is a reference vehicle for study which consists of payload and solid propellant (e.g. ice). A suitable laser pulse is proposed for using a Laser Supported Detonation wave to produce thrust efficiently. It seems likely that a minimum system (10 Mw CO2 laser and 10 m dia. mirror) could be constructed for about $150 M. This minimum system could launch payloads of about 13 kg to a 400 km orbit every 10 minutes. The annual launch capability would be about 683 tons times the duty factor. Laser propulsion would be an order of magnitude cheaper than chemical rockets if the duty factor was 20 percent (10,000 launches/yr). Launches beyond that would be even cheaper. The chief problem which needs to be addressed before these possibilities could be realized is the design of a propellant to turn laser energy into thrust efficiently and to withstand the launch environment.

  8. A Review of Laser Ablation Propulsion

    International Nuclear Information System (INIS)

    Phipps, Claude; Bohn, Willy; Lippert, Thomas; Sasoh, Akihiro; Schall, Wolfgang; Sinko, John

    2010-01-01

    Laser Ablation Propulsion is a broad field with a wide range of applications. We review the 30-year history of laser ablation propulsion from the transition from earlier pure photon propulsion concepts of Oberth and Saenger through Kantrowitz's original laser ablation propulsion idea to the development of air-breathing 'Lightcraft' and advanced spacecraft propulsion engines. The polymers POM and GAP have played an important role in experiments and liquid ablation fuels show great promise. Some applications use a laser system which is distant from the propelled object, for example, on another spacecraft, the Earth or a planet. Others use a laser that is part of the spacecraft propulsion system on the spacecraft. Propulsion is produced when an intense laser beam strikes a condensed matter surface and produces a vapor or plasma jet. The advantages of this idea are that exhaust velocity of the propulsion engine covers a broader range than is available from chemistry, that it can be varied to meet the instantaneous demands of the particular mission, and that practical realizations give lower mass and greater simplicity for a payload delivery system. We review the underlying theory, buttressed by extensive experimental data. The primary problem in laser space propulsion theory has been the absence of a way to predict thrust and specific impulse over the transition from the vapor to the plasma regimes. We briefly discuss a method for combining two new vapor regime treatments with plasma regime theory, giving a smooth transition from one regime to the other. We conclude with a section on future directions.

  9. Pulsed power

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    The key element of our pulsed power program is concentration of power in time and space by suppression of breakdown in dielectrics and in vacuum. Magnetically insulated vacuum transmission lines and magnetic suppression of insulator flashover have continued as the main reserch directions. Vacuum insulated line studies at Physics International have been expanded and a test bed at Sandia, called MITE (Magnetically Insulated Transmission Experiment), is under development. The choice for the baseline EBFA design will depend on the outcome of these studies and should be made in July 1977. The slow and intermediate speed pulsed power approaches to EBFA will be based on Proto I and Proto II results and several of the projected EBFA subsystems are presently being tested in Proto II. A further stage of power concentration, within the vacuum diode itself, would considerably ease the burden on dielectrics; methods of power multiplication involving magnetically imploded plasmas are being considered and tests have begun using the Ripple III apparatus

  10. Historical perspectives: The role of the NASA Lewis Research Center in the national space nuclear power programs

    Science.gov (United States)

    Bloomfield, H. S.; Sovie, R. J.

    1991-01-01

    The history of the NASA Lewis Research Center's role in space nuclear power programs is reviewed. Lewis has provided leadership in research, development, and the advancement of space power and propulsion systems. Lewis' pioneering efforts in nuclear reactor technology, shielding, high temperature materials, fluid dynamics, heat transfer, mechanical and direct energy conversion, high-energy propellants, electric propulsion and high performance rocket fuels and nozzles have led to significant technical and management roles in many national space nuclear power and propulsion programs.

  11. Historical perspectives - The role of the NASA Lewis Research Center in the national space nuclear power programs

    Science.gov (United States)

    Bloomfield, H. S.; Sovie, R. J.

    1991-01-01

    The history of the NASA Lewis Research Center's role in space nuclear power programs is reviewed. Lewis has provided leadership in research, development, and the advancement of space power and propulsion systems. Lewis' pioneering efforts in nuclear reactor technology, shielding, high temperature materials, fluid dynamics, heat transfer, mechanical and direct energy conversion, high-energy propellants, electric propulsion and high performance rocket fuels and nozzles have led to significant technical and management roles in many natural space nuclear power and propulsion programs.

  12. The ALP-PALS Project: optimal coupling for laser propulsion

    Science.gov (United States)

    Boody, F. P.; Badziak, J.; Eckel, H.-A.; Gammino, S.; Krása, J.; Láska, L.; Mezzasalma, A.; Pakhomov, A. J.; Parys, P.; Pfeifer, M.; Pisarczyk, T.; Rohlena, K.; Schall, W.; Torrisi, L.; Wołowski, J.

    2006-05-01

    Since the early 1970s ablative laser propulsion (ALP) has promised to revolutionize space travel by reducing the 30:1 propellant/payload ratio needed for near-earth orbit by up to a factor of 50, by leaving the power source on the ground. But the necessary sub-ns high average power lasers were not available. Dramatic recent progress in laser diodes for pumping solid-state lasers is changing that. Recent results from military laser weapons R&D programs, combined with progress on ceramic disk lasers, suddenly promise lasers powerful enough for automobile-size, if not space shuttle-size payloads, not only the 4 - 10 kg "microsatellites" foreseen just a few years ago. For ALP, the 1.6-μm Er:YAG laser resonantly pumped by InP diode lasers is especially promising. Prior coupling experiments have demonstrated adequate coupling coefficients and specific impulses, but were done with too long pulses and too low pulse energies. The properties of ions produced and the ablated surface were generally not measured but are necessary for understanding and modeling propulsion properties. ALP-PALS will realistically measure ALP parameters using the Prague Asterix Laser System (PALS) high power photodissociation iodine laser (λ = 1.315 μm, E L <=1 kJ, τ ~ 400 ps, beam diameter ~29 cm, flat beam profile) whose parameters match those required for application. PALS' 1.3-μm λ is a little short (vs. 1.53-1.72 μm) but is the closest available and PALS' 2ω / 3ω capability allows wavelength dependence to be studied.

  13. A Combined Solar Electric and Storable Chemical Propulsion Vehicle for Piloted Mars Missions

    Science.gov (United States)

    Mercer, Carolyn R.; Oleson, Steven R.; Drake, Bret G.

    2014-01-01

    The Mars Design Reference Architecture (DRA) 5.0 explored a piloted Mars mission in the 2030 timeframe, focusing on architecture and technology choices. The DRA 5.0 focused on nuclear thermal and cryogenic chemical propulsion system options for the mission. Follow-on work explored both nuclear and solar electric options. One enticing option that was found in a NASA Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) design study used a combination of a 1-MW-class solar electric propulsion (SEP) system combined with storable chemical systems derived from the planned Orion crew vehicle. It was found that by using each propulsion system at the appropriate phase of the mission, the entire SEP stage and habitat could be placed into orbit with just two planned Space Launch System (SLS) heavy lift launch vehicles assuming the crew would meet up at the Earth-Moon (E-M) L2 point on a separate heavy-lift launch. These appropriate phases use high-thrust chemical propulsion only in gravity wells when the vehicle is piloted and solar electric propulsion for every other phase. Thus the SEP system performs the spiral of the unmanned vehicle from low Earth orbit (LEO) to E-M L2 where the vehicle meets up with the multi-purpose crew vehicle. From here SEP is used to place the vehicle on a trajectory to Mars. With SEP providing a large portion of the required capture and departure changes in velocity (delta V) at Mars, the delta V provided by the chemical propulsion is reduced by a factor of five from what would be needed with chemical propulsion alone at Mars. This trajectory also allows the SEP and habitat vehicle to arrive in the highly elliptic 1-sol parking orbit compatible with envisioned Mars landing concepts. This paper explores mission options using between SEP and chemical propulsion, the design of the SEP system including the solar array and electric propulsion systems, and packaging in the SLS shroud. Design trades of stay time, power level

  14. Is effective force application in handrim wheelchair propulsion also efficient?

    NARCIS (Netherlands)

    Bregman, D.J.J.; van Drongelen, S.V.; Veeger, H.E.J.

    2009-01-01

    Background: Efficiency in manual wheelchair propulsion is low, as is the fraction of the propulsion force that is attributed to the moment of propulsion of the wheelchair. In this study we tested the hypothesis that a tangential propulsion force direction leads to an increase in physiological cost,

  15. Power generation from nuclear reactors in aerospace applications

    International Nuclear Information System (INIS)

    English, R.E.

    1982-01-01

    Power generation in nuclear powerplants in space is addressed. In particular, the states of technology of the principal competitive concepts for power generation are assessed. The possible impact of power conditioning on power generation is also discussed. For aircraft nuclear propulsion, the suitability of various technologies is cursorily assessed for flight in the Earth's atmosphere. A program path is suggested to ease the conditions of first use of aircraft nuclear propulsion

  16. Power generation from nuclear reactors in aerospace applications

    Energy Technology Data Exchange (ETDEWEB)

    English, R.E.

    1982-01-01

    Power generation in nuclear powerplants in space is addressed. In particular, the states of technology of the principal competitive concepts for power generation are assessed. The possible impact of power conditioning on power generation is also discussed. For aircraft nuclear propulsion, the suitability of various technologies is cursorily assessed for flight in the Earth's atmosphere. A program path is suggested to ease the conditions of first use of aircraft nuclear propulsion.

  17. High Power Helicon Plasma Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed work seeks to develop and optimize an electrode-less plasma propulsion system that is based on a high power helicon (HPH) that is being developed...

  18. Status of Advanced Propulsion Technology in Japan

    Science.gov (United States)

    1982-03-01

    This report describes the efforts of the Japanese transit industry, which includes manufacturers and transit operators, in the area of advanced propulsion systems for urban rail vehicles. It presents different chopper system designs, new ac drive dev...

  19. Authentication for Propulsion Test Streaming Video

    Data.gov (United States)

    National Aeronautics and Space Administration — A streaming video system was developed and implemented at SSC to support various propulsion projects at SSC. These projects included J-2X and AJ-26 rocket engine...

  20. Jet Propulsion Laboratory: Outsider or insider?

    Science.gov (United States)

    1980-01-01

    The working relationship between NASA and the Jet Propulsion Laboratory is examined in a historical context. The problems which developed due to the facility's close university association are addressed.

  1. Hybrid Electric Propulsion Technologies for Commercial Transports

    Science.gov (United States)

    Bowman, Cheryl; Jansen, Ralph; Jankovsky, Amy

    2016-01-01

    NASA Aeronautics Research Mission Directorate has set strategic research thrusts to address the major drivers of aviation such as growth in demand for high-speed mobility, addressing global climate and capitalizing in the convergence of technological advances. Transitioning aviation to low carbon propulsion is one of the key strategic research thrust and drives the search for alternative and greener propulsion system for advanced aircraft configurations. This work requires multidisciplinary skills coming from multiple entities. The Hybrid Gas-Electric Subproject in the Advanced Air Transportation Project is energizing the transport class landscape by accepting the technical challenge of identifying and validating a transport class aircraft with net benefit from hybrid propulsion. This highly integrated aircraft of the future will only happen if airframe expertise from NASA Langley, modeling and simulation expertise from NASA Ames, propulsion expertise from NASA Glenn, and the flight research capabilities from NASA Armstrong are brought together to leverage the rich capabilities of U.S. Industry and Academia.

  2. High Power Helicon Plasma Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A new thruster has been conceived and tested that is based on a high power helicon (HPH) plasma wave. In this new method of propulsion, an antenna generates and...

  3. Propulsion Wheel Motor for an Electric Vehicle

    Science.gov (United States)

    Figuered, Joshua M. (Inventor); Herrera, Eduardo (Inventor); Waligora, Thomas M. (Inventor); Bluethmann, William J. (Inventor); Farrell, Logan Christopher (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Winn, Ross Briant (Inventor); Eggleston, IV, Raymond Edward (Inventor); Guo, Raymond (Inventor); hide

    2016-01-01

    A wheel assembly for an electric vehicle includes a wheel rim that is concentrically disposed about a central axis. A propulsion-braking module is disposed within an interior region of the wheel rim. The propulsion-braking module rotatably supports the wheel rim for rotation about the central axis. The propulsion-braking module includes a liquid cooled electric motor having a rotor rotatable about the central axis, and a stator disposed radially inside the rotor relative to the central axis. A motor-wheel interface hub is fixedly attached to the wheel rim, and is directly attached to the rotor for rotation with the rotor. The motor-wheel interface hub directly transmits torque from the electric motor to the wheel rim at a 1:1 ratio. The propulsion-braking module includes a drum brake system having an electric motor that rotates a cam device, which actuates the brake shoes.

  4. Cycloidal Propulsion for UAV VTOL Applications

    National Research Council Canada - National Science Library

    Boschma, James

    1998-01-01

    .... This propulsion concept holds significant promise for adaptation to UAV VTOL operations. Thrust levels demonstrated were substantially higher than achievable by the best screw type propellers, and approximately equal to those of high end helicopters...

  5. Breakthrough Propulsion Physics Workshop Preliminary Results

    Science.gov (United States)

    Millis, Marc G.

    1997-01-01

    In August, 1997, a NASA workshop was held to assess the prospects emerging from physics that might lead to creating the ultimate breakthroughs in space transportation: propulsion that requires no propellant mass, attaining the maximum transit speeds physically possible, and breakthrough methods of energy production to power such devices. Because these propulsion goals are presumably far from fruition, a special emphasis was to identify affordable, near-term, and credible research that could make measurable progress toward these propulsion goals. Experiments and theories were discussed regarding the coupling of gravity and electromagnetism, vacuum fluctuation energy, warp drives and wormholes, and superluminal quantum tunneling. Preliminary results of this workshop are presented, along with the status of the Breakthrough Propulsion Physics program that conducted this workshop.

  6. Superconducting Aero Propulsion Motor, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Superconducting electric propulsion systems will yield improvements in total ownership costs due to the simplicity of electric drive when compared with gas turbine...

  7. Test report : alternative fuels propulsion durability evaluation

    Science.gov (United States)

    2012-08-28

    This document, prepared by Honeywell Aerospace, Phoenix, AZ (Honeywell), contains the final : test report (public version) for the U.S. Department of Transportation/Federal Aviation : Administration (USDOT/FAA) Alternative Fuels Propulsion Engine Dur...

  8. Propulsion mechanism for stray X radiation grid

    International Nuclear Information System (INIS)

    1975-01-01

    An improvement in the mechanical part of X-ray equipment for tomography is described. A propulsion mechanism for the stray radiation grid in relation to the radiation source is invented which prevents overloading by automatic decoupling and recoupling

  9. Effects of shape and stroke parameters on the propulsion performance of an axisymmetric swimmer

    International Nuclear Information System (INIS)

    Peng Jifeng; Alben, Silas

    2012-01-01

    In nature, there exists a special group of aquatic animals which have an axisymmetric body and whose primary swimming mechanism is to use periodic body contractions to generate vortex rings in the surrounding fluid. Using jellyfish medusae as an example, this study develops a mathematical model of body kinematics of an axisymmetric swimmer and uses a computational approach to investigate the induced vortex wakes. Wake characteristics are identified for swimmers using jet propulsion and rowing, two mechanisms identified in previous studies of medusan propulsion. The parameter space of body kinematics is explored through four quantities: a measure of body shape, stroke amplitude, the ratio between body contraction duration and extension duration, and the pulsing frequency. The effects of these parameters on thrust, input power requirement and circulation production are quantified. Two metrics, cruising speed and energy cost of locomotion, are used to evaluate the propulsion performance. The study finds that a more prolate-shaped swimmer with larger stroke amplitudes is able to swim faster, but its cost of locomotion is also higher. In contrast, a more oblate-shaped swimmer with smaller stroke amplitudes uses less energy for its locomotion, but swims more slowly. Compared with symmetric strokes with equal durations of contraction and extension, faster bell contractions increase the swimming speed whereas faster bell extensions decrease it, but both require a larger energy input. This study shows that besides the well-studied correlations between medusan body shape and locomotion, stroke variables also affect the propulsion performance. It provides a framework for comparing the propulsion performance of axisymmetric swimmers based on their body kinematics when it is difficult to measure and analyze their wakes empirically. The knowledge from this study is also useful for the design of robotic swimmers that use axisymmetric body contractions for propulsion. (paper)

  10. MW-Class Electric Propulsion System Designs for Mars Cargo Transport

    Science.gov (United States)

    Gilland, James H.; LaPointe, Michael R.; Oleson, Steven; Mercer, Carolyn; Pencil, Eric; Maosn, Lee

    2011-01-01

    Multi-kilowatt electric propulsion systems are well developed and have been used on commercial and military satellites in Earth orbit for several years. Ion and Hall thrusters have also propelled robotic spacecraft to encounters with asteroids, the Moon, and minor planetary bodies within the solar system. High power electric propulsion systems are currently being considered to support piloted missions to near earth asteroids, as cargo transport for sustained lunar or Mars exploration, and for very high-power piloted missions to Mars and the outer planets. Using NASA Mars Design Architecture 5.0 as a reference, a preliminary parametric analysis was performed to determine the suitability of a nuclear powered, MW-class electric propulsion system for Mars cargo transport. For this initial analysis, high power 100-kW Hall thrusters and 250-kW VASIMR engines were separately evaluated to determine optimum vehicle architecture and estimated performance. The DRA 5.0 cargo mission closed for both propulsion options, delivering a 100 t payload to Mars orbit and reducing the number of heavy lift launch vehicles from five in the baseline DRA 5.0 architecture to two using electric propulsion. Under an imposed single engine-out mission success criteria, the VASIMR system took longer to reach Mars than did the Hall system, arising from the need to operate the VASIMR thrusters in pairs during the spiral out from low Earth orbit.

  11. Electric Propulsion System Characterization through Experiments

    OpenAIRE

    Hattenberger, Gautier; Drouin, Antoine; Bronz, Murat

    2016-01-01

    International audience; Electrical propulsion system characteristics are very important in UAV design, operation and control. This article presents the characterization of electric propulsion sets through experiments. A motor test bench have been build based on previous experience in order to improve the quality of the measurements. Moreover, the bench fits in a wind tunnel, allowing to perform a complete characterization over the full airspeed range of the considered mini and micro-UAVs. Aft...

  12. Modifications in Wheelchair Propulsion Technique with Speed

    Directory of Open Access Journals (Sweden)

    Ian Miles Russell

    2015-10-01

    Full Text Available Objective: Repetitive loading of the upper limb joints during manual wheelchair propulsion has been identified a factor that contributes to shoulder pain, leading to loss of independence and decreased quality of life. The purpose of this study was to determine how individual manual wheelchair users with paraplegia modify propulsion mechanics to accommodate expected increases in reaction forces generated at the pushrim with self-selected increases in wheelchair propulsion (WCP speed.Methods: Upper extremity kinematics and pushrim reaction forces were measured for 40 experienced manual wheelchair users with paraplegia while propelling on a stationary ergometer at self-selected free and fast propulsion speeds. Upper extremity kinematics and kinetics were compared within-subject between propulsion speeds. Between group and within subject differences were determined (α =0.05.Results: Increased propulsion speed was accompanied by increases in Reaction Force (RF magnitude (22 of 40, >10N and shoulder Net Joint Moment (NJM, 15 of 40, >10Nm and decreases in pushrim contact duration. Within-subject comparison indicated that 27% of participants modified their WCP mechanics with increases in speed by regulating RF orientation relative to the upper extremity segments.Conclusions: Reorientation of the RF relative to the upper extremity segments can be used as an effective strategy for mitigating rotational demands (NJM imposed on the shoulder at increased propulsion speeds. Identification of propulsion strategies that individuals can use to effectively accommodate for increases in RFs is an important step towards preserving musculoskeletal health of the shoulder and improving health-related quality of life.

  13. Digital image correlation, acoustic emission and ultrasonic pulse velocity for the detection of cracks in the concrete buffer of the Belgian nuclear supercontainer

    International Nuclear Information System (INIS)

    Iliopoulos, Sokratis; Tsangouri, Eleni; Aggelis, Dimitrios G.; Pyl, Lincy; Areias, Lou; Vrije Univ., Brussels

    2014-01-01

    The long term management of high-level and heat emitting radioactive waste is a worldwide concern, as it directly influences the environment and future generations. To address this issue, the Belgian Agency for Radioactive Waste and Enriched Fissile Materials has come up with the conceptual design of a massive concrete structure called Supercontainer. The feasibility to construct these structures is being evaluated through a number of scaled models that are tested using classical as well as state of the art measurement techniques. In the current paper, the results obtained from the simultaneous application of the Digital Image Correlation (DIC), the Acoustic Emission (AE) and the Ultrasonic Pulse Velocity (UPV) nondestructive testing techniques on the second scaled model for the detection and monitoring of cracks will be presented.

  14. Visions of the Future: Hybrid Electric Aircraft Propulsion

    Science.gov (United States)

    Bowman, Cheryl L.

    2016-01-01

    The National Aeronautics and Space Administration (NASA) is investing continually in improving civil aviation. Hybridization of aircraft propulsion is one aspect of a technology suite which will transform future aircraft. In this context, hybrid propulsion is considered a combination of traditional gas turbine propulsion and electric drive enabled propulsion. This technology suite includes elements of propulsion and airframe integration, parallel hybrid shaft power, turbo-electric generation, electric drive systems, component development, materials development and system integration at multiple levels.

  15. Nonsinusoidal gaits for unsteady propulsion

    Science.gov (United States)

    Van Buren, T.; Floryan, D.; Quinn, D.; Smits, A. J.

    2017-05-01

    The impact of wave-form shape on the wake and propulsive performance of a pitching and heaving two-dimensional foil is explored experimentally. Jacobi elliptic functions are used to define wave-form shapes that are approximately triangular, sinusoidal, or square. The triangular-like and sinusoidal waves produce qualitatively similar wakes, with a typical reverse von Kármán vortex street structure leading to a jetlike wake in the mean. Square-like motions produce very different results, with a vortex pair shed every half cycle, leading to a mean wake with two distinct off-center jets, and a significant change in the thrust production, yielding up to four times more thrust for a given Strouhal number. Performance curves indicate that to swim most efficiently sinusoidal motions are best, whereas the square-like motions lead to higher speeds. A scaling analysis indicates that the peak lateral velocity appears to be the dominant parameter in characterizing the performance of the nonsinusoidal motions.

  16. Breakthrough Propulsion Physics Project: Project Management Methods

    Science.gov (United States)

    Millis, Marc G.

    2004-01-01

    To leap past the limitations of existing propulsion, the NASA Breakthrough Propulsion Physics (BPP) Project seeks further advancements in physics from which new propulsion methods can eventually be derived. Three visionary breakthroughs are sought: (1) propulsion that requires no propellant, (2) propulsion that circumvents existing speed limits, and (3) breakthrough methods of energy production to power such devices. Because these propulsion goals are presumably far from fruition, a special emphasis is to identify credible research that will make measurable progress toward these goals in the near-term. The management techniques to address this challenge are presented, with a special emphasis on the process used to review, prioritize, and select research tasks. This selection process includes these key features: (a) research tasks are constrained to only address the immediate unknowns, curious effects or critical issues, (b) reliability of assertions is more important than the implications of the assertions, which includes the practice where the reviewers judge credibility rather than feasibility, and (c) total scores are obtained by multiplying the criteria scores rather than by adding. Lessons learned and revisions planned are discussed.

  17. Propulsion in cubomedusae: mechanisms and utility.

    Directory of Open Access Journals (Sweden)

    Sean P Colin

    Full Text Available Evolutionary constraints which limit the forces produced during bell contractions of medusae affect the overall medusan morphospace such that jet propulsion is limited to only small medusae. Cubomedusae, which often possess large prolate bells and are thought to swim via jet propulsion, appear to violate the theoretical constraints which determine the medusan morphospace. To examine propulsion by cubomedusae, we quantified size related changes in wake dynamics, bell shape, swimming and turning kinematics of two species of cubomedusae, Chironex fleckeri and Chiropsella bronzie. During growth, these cubomedusae transitioned from using jet propulsion at smaller sizes to a rowing-jetting hybrid mode of propulsion at larger sizes. Simple modifications in the flexibility and kinematics of their velarium appeared to be sufficient to alter their propulsive mode. Turning occurs during both bell contraction and expansion and is achieved by generating asymmetric vortex structures during both stages of the swimming cycle. Swimming characteristics were considered in conjunction with the unique foraging strategy used by cubomedusae.

  18. PULSE COLUMN

    Science.gov (United States)

    Grimmett, E.S.

    1964-01-01

    This patent covers a continuous countercurrent liquidsolids contactor column having a number of contactor states each comprising a perforated plate, a layer of balls, and a downcomer tube; a liquid-pulsing piston; and a solids discharger formed of a conical section at the bottom of the column, and a tubular extension on the lowest downcomer terminating in the conical section. Between the conical section and the downcomer extension is formed a small annular opening, through which solids fall coming through the perforated plate of the lowest contactor stage. This annular opening is small enough that the pressure drop thereacross is greater than the pressure drop upward through the lowest contactor stage. (AEC)

  19. Space Nuclear Power Systems

    Science.gov (United States)

    Houts, Michael G.

    2012-01-01

    Fission power and propulsion systems can enable exciting space exploration missions. These include bases on the moon and Mars; and the exploration, development, and utilization of the solar system. In the near-term, fission surface power systems could provide abundant, constant, cost-effective power anywhere on the surface of the Moon or Mars, independent of available sunlight. Affordable access to Mars, the asteroid belt, or other destinations could be provided by nuclear thermal rockets. In the further term, high performance fission power supplies could enable both extremely high power levels on planetary surfaces and fission electric propulsion vehicles for rapid, efficient cargo and crew transfer. Advanced fission propulsion systems could eventually allow routine access to the entire solar system. Fission systems could also enable the utilization of resources within the solar system.

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

    Science.gov (United States)

    Anderson, David; Kamhawi, Hani; Patterson, Mike; Pencil, Eric; Pinero, Luis; Falck, Robert; Dankanich, John

    2014-01-01

    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.