WorldWideScience

Sample records for bipropellant propulsion subsystem

  1. Primary electric propulsion thrust subsystem definition

    Science.gov (United States)

    Masek, T. D.; Ward, J. W.; Kami, S.

    1975-01-01

    A review is presented of the current status of primary propulsion thrust subsystem (TSS) performance, packaging considerations, and certain operational characteristics. Thrust subsystem related work from recent studies by Jet Propulsion Laboratories (JPL), Rockwell and Boeing is discussed. Existing performance for 30-cm thrusters, power processors and TSS is present along with projections for future improvements. Results of analyses to determine (1) magnetic field distributions resulting from an array of thrusters, (2) thruster emitted particle flux distributions from an array of thrusters, and (3) TSS element failure rates are described to indicate the availability of analytical tools for evaluation of TSS designs.

  2. Launch Vehicle Performance for Bipropellant Propulsion Using Atomic Propellants With Oxygen

    Science.gov (United States)

    Palaszewski, Bryan

    2000-01-01

    Atomic propellants for bipropellant launch vehicles using atomic boron, carbon, and hydrogen were analyzed. The gross liftoff weights (GLOW) and dry masses of the vehicles were estimated, and the 'best' design points for atomic propellants were identified. Engine performance was estimated for a wide range of oxidizer to fuel (O/F) ratios, atom loadings in the solid hydrogen particles, and amounts of helium carrier fluid. Rocket vehicle GLOW was minimized by operating at an O/F ratio of 1.0 to 3.0 for the atomic boron and carbon cases. For the atomic hydrogen cases, a minimum GLOW occurred when using the fuel as a monopropellant (O/F = 0.0). The atomic vehicle dry masses are also presented, and these data exhibit minimum values at the same or similar O/F ratios as those for the vehicle GLOW. A technology assessment of atomic propellants has shown that atomic boron and carbon rocket analyses are considered to be much more near term options than the atomic hydrogen rockets. The technology for storing atomic boron and carbon has shown significant progress, while atomic hydrogen is not able to be stored at the high densities needed for effective propulsion. The GLOW and dry mass data can be used to estimate the cost of future vehicles and their atomic propellant production facilities. The lower the propellant's mass, the lower the overall investment for the specially manufactured atomic propellants.

  3. Advanced Transportation System Studies. Technical Area 3: Alternate Propulsion Subsystem Concepts. Volume 1; Executive Summary

    Science.gov (United States)

    Levack, Daniel J. H.

    2000-01-01

    The Alternate Propulsion Subsystem Concepts contract had seven tasks defined that are reported under this contract deliverable. The tasks were: FAA Restart Study, J-2S Restart Study, Propulsion Database Development. SSME Upper Stage Use. CERs for Liquid Propellant Rocket Engines. Advanced Low Cost Engines, and Tripropellant Comparison Study. The two restart studies, F-1A and J-2S, generated program plans for restarting production of each engine. Special emphasis was placed on determining changes to individual parts due to obsolete materials, changes in OSHA and environmental concerns, new processes available, and any configuration changes to the engines. The Propulsion Database Development task developed a database structure and format which is easy to use and modify while also being comprehensive in the level of detail available. The database structure included extensive engine information and allows for parametric data generation for conceptual engine concepts. The SSME Upper Stage Use task examined the changes needed or desirable to use the SSME as an upper stage engine both in a second stage and in a translunar injection stage. The CERs for Liquid Engines task developed qualitative parametric cost estimating relationships at the engine and major subassembly level for estimating development and production costs of chemical propulsion liquid rocket engines. The Advanced Low Cost Engines task examined propulsion systems for SSTO applications including engine concept definition, mission analysis. trade studies. operating point selection, turbomachinery alternatives, life cycle cost, weight definition. and point design conceptual drawings and component design. The task concentrated on bipropellant engines, but also examined tripropellant engines. The Tripropellant Comparison Study task provided an unambiguous comparison among various tripropellant implementation approaches and cycle choices, and then compared them to similarly designed bipropellant engines in the

  4. Definition of an arcjet propulsion sub-system

    International Nuclear Information System (INIS)

    Price, T.W.

    1989-01-01

    An engineering flight demonstration of a 100 kW3 Space Reactor Power System is planned for the mid to late 1990s. An arcjet based propulsion subsystem will be included on the flight demonstraction as a secondary experiment. Two studies, sponsored by the Kay Technologies Directorate of the SDI Organization and managed by the Jet Propulsion Laboratory are currently under way to define that propulsion subsystem. The principal tasks of those contracts and the plans for two later phases, an experimental verification of the concept and a flight qualification/delivery of a flight unit, are described. 9 refs

  5. High Energy, Low Temperature Gelled Bi-Propellant Formulation for Long-Duration In-Space Propulsion, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Development of a candidate bi-propellant system consisting of a gelled hydrocarbon fuel coupled with a highly energetic gelled oxidizer suitable for outer planetary...

  6. Solid Propulsion Systems, Subsystems, and Components Service Life Extension

    Science.gov (United States)

    Hundley, Nedra H.; Jones, Connor

    2011-01-01

    The service life extension of solid propulsion systems, subsystems, and components will be discussed based on the service life extension of the Space Transportation System Reusable Solid Rocket Motor (RSRM) and Booster Separation Motors (BSM). The RSRM is certified for an age life of five years. In the aftermath of the Columbia accident there were a number of motors that were approaching the end of their five year service life certification. The RSRM Project initiated an assessment to determine if the service life of these motors could be extended. With the advent of the Constellation Program, a flight test was proposed that would utilize one of the RSRMs which had been returned from the launch site due to the expiration of its five year service life certification and twelve surplus Chemical Systems Division BSMs which had exceeded their eight year service life. The RSRM age life tracking philosophy which establishes when the clock starts for age life tracking will be described. The role of the following activities in service life extension will be discussed: subscale testing, accelerated aging, dissecting full scale aged hardware, static testing full scale aged motors, data mining industry data, and using the fleet leader approach. The service life certification and extension of the BSMs will also be presented.

  7. NASA Propulsion Sub-System Concept Studies and Risk Reduction Activities for Resource Prospector Lander

    Science.gov (United States)

    Trinh, Huu P.

    2015-01-01

    NASA's exploration roadmap is focused on developing technologies and performing precursor missions to advance the state of the art for eventual human missions to Mars. One of the key components of this roadmap is various robotic missions to Near-Earth Objects, the Moon, and Mars to fill in some of the strategic knowledge gaps. The Resource Prospector (RP) project is one of these robotic precursor activities in the roadmap. RP is a multi-center and multi-institution project to investigate the polar regions of the Moon in search of volatiles. The mission is rated Class D and is approximately 10 days, assuming a five day direct Earth to Moon transfer. Because of the mission cost constraint, a trade study of the propulsion concepts was conducted with a focus on available low-cost hardware for reducing cost in development, while technical risk, system mass, and technology advancement requirements were also taken into consideration. The propulsion system for the lander is composed of a braking stage providing a high thrust to match the lander's velocity with the lunar surface and a lander stage performing the final lunar descent. For the braking stage, liquid oxygen (LOX) and liquid methane (LCH4) propulsion systems, derived from the Morpheus experimental lander, and storable bi-propellant systems, including the 4th stage Peacekeeper (PK) propulsion components and Space Shuttle orbital maneuvering engine (OME), and a solid motor were considered for the study. For the lander stage, the trade study included miniaturized Divert Attitude Control System (DACS) thrusters (Missile Defense Agency (MDA) heritage), their enhanced thruster versions, ISE-100 and ISE-5, and commercial-off-the-shelf (COTS) hardware. The lowest cost configuration of using the solid motor and the PK components while meeting the requirements was selected. The reference concept of the lander is shown in Figure 1. In the current reference configuration, the solid stage is the primary provider of delta

  8. Integrated flight/propulsion control - Subsystem specifications for performance

    Science.gov (United States)

    Neighbors, W. K.; Rock, Stephen M.

    1993-01-01

    A procedure is presented for calculating multiple subsystem specifications given a number of performance requirements on the integrated system. This procedure applies to problems where the control design must be performed in a partitioned manner. It is based on a structured singular value analysis, and generates specifications as magnitude bounds on subsystem uncertainties. The performance requirements should be provided in the form of bounds on transfer functions of the integrated system. This form allows the expression of model following, command tracking, and disturbance rejection requirements. The procedure is demonstrated on a STOVL aircraft design.

  9. Tests of an alternating current propulsion subsystem for electric vehicles on a road load simulator

    Science.gov (United States)

    Stenger, F. J.

    1982-12-01

    The test results of a breadboard version of an ac electric-vehicle propulsion subsystem are presented. The breadboard was installed in the NASA Lewis Research Center Road Load Simulator facility and tested under steady-state and transient conditions. Steady-state tests were run to characterize the system and component efficiencies over the complete speed-torque range within the capability of the propulsion subsystem in the motoring mode of operation. Transient tests were performed to determine the energy consumption of the breadboard over the acceleration and cruise portions of SAE J227 and driving schedules B, C, and D. Tests in the regenerative mode were limited to the low-gear-speed range of the two speed transaxle used in the subsystem. The maximum steady-state subsystem efficiency observed for the breadboard was 81.5 percent in the high-gear-speed range in the motoring mode, and 76 percent in the regenerative braking mode (low gear). The subsystem energy efficiency during the transient tests ranged from 49.2 percent for schedule B to 68.4 percent for Schedule D.

  10. Advanced transportation system studies technical area 3: Alternate propulsion subsystem concepts, volume 2

    Science.gov (United States)

    Levak, Daniel

    1993-01-01

    The Alternate Propulsion Subsystem Concepts contract had five tasks defined for the first year. The tasks were: F-1A Restart Study, J-2S Restart Study, Propulsion Database Development, Space Shuttle Main Engine (SSME) Upper Stage Use, and CER's for Liquid Propellant Rocket Engines. The detailed study results, with the data to support the conclusions from various analyses, are being reported as a series of five separate Final Task Reports. Consequently, this volume only reports the required programmatic information concerning Computer Aided Design Documentation, and New Technology Reports. A detailed Executive Summary, covering all the tasks, is also available as Volume 1.

  11. High-Performance, Space-Storable, Bi-Propellant Program Status

    Science.gov (United States)

    Schneider, Steven J.

    2002-01-01

    Bipropellant propulsion systems currently represent the largest bus subsystem for many missions. These missions range from low Earth orbit satellite to geosynchronous communications and planetary exploration. The payoff of high performance bipropellant systems is illustrated by the fact that Aerojet Redmond has qualified a commercial NTO/MMH engine based on the high Isp technology recently delivered by this program. They are now qualifying a NTO/hydrazine version of this engine. The advanced rhenium thrust chambers recently provided by this program have raised the performance of earth storable propellants from 315 sec to 328 sec of specific impulse. The recently introduced rhenium technology is the first new technology introduced to satellite propulsion in 30 years. Typically, the lead time required to develop and qualify new chemical thruster technology is not compatible with program development schedules. These technology development programs must be supported by a long term, Base R&T Program, if the technology s to be matured. This technology program then addresses the need for high performance, storable, on-board chemical propulsion for planetary rendezvous and descent/ascent. The primary NASA customer for this technology is Space Science, which identifies this need for such programs as Mars Surface Return, Titan Explorer, Neptune Orbiter, and Europa Lander. High performance (390 sec) chemical propulsion is estimated to add 105% payload to the Mars Sample Return mission or alternatively reduce the launch mass by 33%. In many cases, the use of existing (flight heritage) propellant technology is accommodated by reducing mission objectives and/or increasing enroute travel times sacrificing the science value per unit cost of the program. Therefore, a high performance storable thruster utilizing fluorinated oxidizers with hydrazine is being developed.

  12. Reusable Reentry Satellite (RRS): Propulsion system trade study

    Science.gov (United States)

    1990-01-01

    The purpose of the Reusable Reentry Satellite (RRS) Propulsion System Trade Study described in this summary report was to investigate various propulsion options available for incorporation on the RRS and to select the option best suited for RRS application. The design requirements for the RRS propulsion system were driven by the total impulse requirements necessary to operate within the performance envelope specified in the RRS System Requirements Documents. These requirements were incorporated within the Design Reference Missions (DRM's) identified for use in this and other subsystem trade studies. This study investigated the following propulsion systems: solid rocket, monopropellant, bipropellant (monomethyl hydrazine and nitrogen tetroxide or MMH/NTO), dual-mode bipropellant (hydrazine and nitrogen tetroxide or N2H4/NTO), liquid oxygen and liquid hydrogen (LO2/LH2), and an advanced design propulsion system using SDI-developed components. A liquid monopropellant blowdown propulsion system was found to be best suited for meeting the RRS requirements and is recommended as the baseline system. This system was chosen because it is the simplest of all investigated, has the fewest components, and is the most cost effective. The monopropellant system meets all RRS performance requirements and has the capability to provide a very accurate deorbit burn which minimizes reentry dispersions. In addition, no new hardware qualification is required for a monopropellant system. Although the bipropellant systems offered some weight savings capability for missions requiring large deorbit velocities, the advantage of a lower mass system only applies if the total vehicle design can be reduced to allow a cheaper launch vehicle to be used. At the time of this trade study, the overall RRS weight budget and launch vehicle selection were not being driven by the propulsion system selection. Thus, the added cost and complexity of more advanced systems did not warrant application.

  13. An Overview of the CNES Propulsion Program for Spacecraft

    Science.gov (United States)

    Cadiou, A.; Darnon, F.; Gibek, I.; Jolivet, L.; Pillet, N.

    2004-10-01

    This paper presents an overview of the CNES spacecraft propulsion activities. The main existing and future projects corresponding to low earth orbit and geostationary platforms are described. These projects cover various types of propulsion subsystems: monopropellant, bipropellant and electric. Monopropellant is mainly used for low earth orbit applications such as earth observation (SPOT/Helios, PLEIADES) or scientific applications (minisatellite PROTEUS line and micro satellites MYRIADE line). Bipropellant is used for geostationary telecommunications satellites (@BUS). The field of application of electric propulsion is the station keeping of geostationary telecommunication satellites (@BUS), main propulsion for specific probes (SMART 1) and fine attitude control for dedicated micro satellites (MICROSCOPE). The preparation of the future and the associated Research and Technology program are also described in the paper. The future developments are mainly dedicated to the performance improvements of electric propulsion which leads to the development of thrusters with higher thrust and higher specific impulse than those existing today, the evaluation of the different low thrust technologies for formation flying applications, the development of new systems to pressurize the propellants (volatile liquid, micro pump), the research on green propellants and different actions concerning components such as over wrapped pressure vessels, valves, micro propulsion. A constant effort is also put on plume effect in chemical and electrical propulsion area (improvement of tools and test activities) in the continuity of the previous work. These different R &T activities are described in detail after a presentation of the different projects and of their propulsion subsystems. The scientific activity supporting the development of Hall thrusters is going on in the frame of the GDR (Groupement de Recherche) CNRS / Universities / CNES / SNECMA on Plasma Propulsion.

  14. A Preliminary Model for Spacecraft Propulsion Performance Analysis Based on Nuclear Gain and Subsystem Mass-Power Balances

    Science.gov (United States)

    Chakrabarti, Suman; Schmidt, George R.; Thio, Y. C.; Hurst, Chantelle M.

    1999-01-01

    A preliminary model for spacecraft propulsion performance analysis based on nuclear gain and subsystem mass-power balances are presented in viewgraph form. For very fast missions with straight-line trajectories, it has been shown that mission trip time is proportional to the cube root of alpha. Analysis of spacecraft power systems via a power balance and examination of gain vs. mass-power ratio has shown: 1) A minimum gain is needed to have enough power for thruster and driver operation; and 2) Increases in gain result in decreases in overall mass-power ratio, which in turn leads to greater achievable accelerations. However, subsystem mass-power ratios and efficiencies are crucial: less efficient values for these can partially offset the effect of nuclear gain. Therefore, it is of interest to monitor the progress of gain-limited subsystem technologies and it is also possible that power-limited systems with sufficiently low alpha may be competitive for such ambitious missions. Topics include Space flight requirements; Spacecraft energy gain; Control theory for performance; Mission assumptions; Round trips: Time and distance; Trip times; Vehicle acceleration; and Minimizing trip times.

  15. Advanced transportation system studies technical area 3: Alternate propulsion subsystem concepts, volume 3

    Science.gov (United States)

    Levak, Daniel

    1993-01-01

    The objective of this contract was to provide definition of alternate propulsion systems for both earth-to-orbit (ETO) and in-space vehicles (upper stages and space transfer vehicles). For such propulsion systems, technical data to describe performance, weight, dimensions, etc. was provided along with programmatic information such as cost, schedule, needed facilities, etc. Advanced technology and advanced development needs were determined and provided. This volume separately presents the various program cost estimates that were generated under three tasks: the F-1A Restart Task, the J-2S Restart Task, and the SSME Upper Stage Use Task. The conclusions, technical results, and the program cost estimates are described in more detail in Volume 1 - Executive Summary and in individual Final Task Reports.

  16. Advanced Transportation System Studies. Technical Area 3: Alternate Propulsion Subsystems Concepts. Volume 3; Program Cost Estimates

    Science.gov (United States)

    Levack, Daniel J. H.

    2000-01-01

    The objective of this contract was to provide definition of alternate propulsion systems for both earth-to-orbit (ETO) and in-space vehicles (upper stages and space transfer vehicles). For such propulsion systems, technical data to describe performance, weight, dimensions, etc. was provided along with programmatic information such as cost, schedule, needed facilities, etc. Advanced technology and advanced development needs were determined and provided. This volume separately presents the various program cost estimates that were generated under three tasks: the F- IA Restart Task, the J-2S Restart Task, and the SSME Upper Stage Use Task. The conclusions, technical results , and the program cost estimates are described in more detail in Volume I - Executive Summary and in individual Final Task Reports.

  17. Independent Orbiter Assessment (IOA): Assessment of the main propulsion subsystem FMEA/CIL, volume 2

    Science.gov (United States)

    Holden, K. A.

    1988-01-01

    The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Main Propulsion System (MPS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were than compared to available data from the Rockwell Downey/NASA JSC FMEA/CIL review. Volume 2 continues the presentation of IOA worksheets for MPS hardware items.

  18. Independent Orbiter Assessment (IOA): Assessment of the main propulsion subsystem FMEA/CIL, volume 4

    Science.gov (United States)

    Slaughter, B. C.

    1988-01-01

    The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Main Propulsion System (MPS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were than compared to available data from the Rockwell Downey/NASA JSC FMEA/CIL review. Volume 4 contains the IOA analysis worksheets and the NASA FMEA to IOA worksheet cross reference and recommendations.

  19. Independent Orbiter Assessment (IOA): Assessment of the main propulsion subsystem FMEA/CIL, volume 3

    Science.gov (United States)

    Holden, K. A.

    1988-01-01

    The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Main Propulsion System (MPS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to available data from the Rockwell Downey/NASA JSC FMEA/CIL review. Volume 3 continues the presentation of IOA worksheets and includes the potential critical items list.

  20. EADS-ST's Latest Bipropellant 10N Thruster and 400 N Engine: The Fully European Solution

    Science.gov (United States)

    Fick, M.; Dreer, T.; Gotzig, U.; Schulte, G.; Bachmann, J.; Lagier, F.; Benoit, E.

    2004-10-01

    Increasing restrictions, complications and bureaucratic hurdles for obtaining export licenses from the US government for American components to be used on certain projects and for certain launch sites or end customers, required the development of new or upgraded European flow control valves to guarantee an independent and unrestricted marketing of EADS-ST's orbital propulsion products to commercial customers worldwide. The development and qualification of the European flow control valves for EADS-ST's 10 N bipropellant thruster and 400 N bipropellant engine is highlighted, together with verification tests and the qualification programs at engine level. The 400 N engine under qualification with the new valves is an enhanced version with an increased area ratio of the nozzle.

  1. Development of a green bipropellant hydrogen peroxide thruster for attitude control on satellites

    Science.gov (United States)

    Woschnak, A.; Krejci, D.; Schiebl, M.; Scharlemann, C.

    2013-03-01

    This document describes the selection assessment of propellants for a 1-newton green bipropellant thruster for attitude control on satellites. The development of this thruster was conducted as a part of the project GRASP (Green Advanced Space Propellants) within the European FP7 research program. The green propellant combinations hydrogen peroxide (highly concentrated with 87.5 %(wt.)) with kerosene or hydrogen peroxide (87.5 %(wt.)) with ethanol were identified as interesting candidates and were investigated in detail with the help of an experimental combustion chamber in the chemical propulsion laboratory at the Forschungsund Technologietransfer GmbH ― Fotec. Based on the test results, a final selection of propellants was performed.

  2. Advanced Chemical Propulsion System Study

    Science.gov (United States)

    Portz, Ron; Alexander, Leslie; Chapman, Jack; England, Chris; Henderson, Scott; Krismer, David; Lu, Frank; Wilson, Kim; Miller, Scott

    2007-01-01

    A detailed; mission-level systems study has been performed to show the benefit resulting from engine performance gains that will result from NASA's In-Space Propulsion ROSS Cycle 3A NRA, Advanced Chemical Technology sub-topic. The technology development roadmap to accomplish the NRA goals are also detailed in this paper. NASA-Marshall and NASA-JPL have conducted mission-level studies to define engine requirements, operating conditions, and interfaces. Five reference missions have been chosen for this analysis based on scientific interest, current launch vehicle capability and trends in space craft size: a) GTO to GEO, 4800 kg, delta-V for GEO insertion only approx.1830 m/s; b) Titan Orbiter with aerocapture, 6620 kg, total delta V approx.210 m/s, mostly for periapsis raise after aerocapture; c) Enceladus Orbiter (Titan aerocapture) 6620 kg, delta V approx.2400 m/s; d) Europa Orbiter, 2170 kg, total delta V approx.2600 m/s; and e) Mars Orbiter, 2250 kg, total delta V approx.1860 m/s. The figures of merit used to define the benefit of increased propulsion efficiency at the spacecraft level include propulsion subsystem wet mass, volume and overall cost. The objective of the NRA is to increase the specific impulse of pressure-fed earth storable bipropellant rocket engines to greater than 330 seconds with nitrogen tetroxide and monomothylhydrazine propellants and greater than 335 , seconds with nitrogen tetroxide and hydrazine. Achievement of the NRA goals will significantly benefit NASA interplanetary missions and other government and commercial opportunities by enabling reduced launch weight and/or increased payload. The study also constitutes a crucial stepping stone to future development, such as pump-fed storable engines.

  3. Comparison study of exhaust plume impingement effects of small mono- and bipropellant thrusters using parallelized DSMC method.

    Directory of Open Access Journals (Sweden)

    Kyun Ho Lee

    Full Text Available A space propulsion system is important for the normal mission operations of a spacecraft by adjusting its attitude and maneuver. Generally, a mono- and a bipropellant thruster have been mainly used for low thrust liquid rocket engines. But as the plume gas expelled from these small thrusters diffuses freely in a vacuum space along all directions, unwanted effects due to the plume collision onto the spacecraft surfaces can dramatically cause a deterioration of the function and performance of a spacecraft. Thus, aim of the present study is to investigate and compare the major differences of the plume gas impingement effects quantitatively between the small mono- and bipropellant thrusters using the computational fluid dynamics (CFD. For an efficiency of the numerical calculations, the whole calculation domain is divided into two different flow regimes depending on the flow characteristics, and then Navier-Stokes equations and parallelized Direct Simulation Monte Carlo (DSMC method are adopted for each flow regime. From the present analysis, thermal and mass influences of the plume gas impingements on the spacecraft were analyzed for the mono- and the bipropellant thrusters. As a result, it is concluded that a careful understanding on the plume impingement effects depending on the chemical characteristics of different propellants are necessary for the efficient design of the spacecraft.

  4. Cyanoborohydride-based ionic liquids as green aerospace bipropellant fuels.

    Science.gov (United States)

    Zhang, Qinghua; Yin, Ping; Zhang, Jiaheng; Shreeve, Jean'ne M

    2014-06-02

    In propellant systems, the most common bipropellants are composed of two chemicals, a fuel (or reducer) and an oxidizer. Currently, the choices for propellant fuels rely mainly on hydrazine and its methylated derivatives, even though they are extremely toxic, highly volatile, sensitive to adiabatic compression (risk of detonation), and, therefore, difficult to handle. With this background, the search for alternative green propellant fuels has been an urgent goal of space science. In this study, a new family of cyanoborohydride-based ionic liquids (ILs) with properties and performances comparable to hydrazine derivatives were designed and synthesized. These new ILs as bipropellant fuels, have some unique advantages including negligible vapor pressure, ultra-short ignition delay (ID) time, and reduced synthetic and storage costs, thereby showing great application potential as environmentally friendly fuels in bipropellant formulations. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Two-step rocket engine bipropellant valve concept

    Science.gov (United States)

    Capps, J. E.; Ferguson, R. E.; Pohl, H. O.

    1969-01-01

    Initiating combustion of altitude control rocket engines in a precombustion chamber of ductile material reduces high pressure surges generated by hypergolic propellants. Two-step bipropellant valve concepts control initial propellant flow into precombustion chamber and subsequent full flow into main chamber.

  6. Advanced Chemical Propulsion Study

    Science.gov (United States)

    Woodcock, Gordon; Byers, Dave; Alexander, Leslie A.; Krebsbach, Al

    2004-01-01

    A study was performed of advanced chemical propulsion technology application to space science (Code S) missions. The purpose was to begin the process of selecting chemical propulsion technology advancement activities that would provide greatest benefits to Code S missions. Several missions were selected from Code S planning data, and a range of advanced chemical propulsion options was analyzed to assess capabilities and benefits re these missions. Selected beneficial applications were found for higher-performing bipropellants, gelled propellants, and cryogenic propellants. Technology advancement recommendations included cryocoolers and small turbopump engines for cryogenic propellants; space storable propellants such as LOX-hydrazine; and advanced monopropellants. It was noted that fluorine-bearing oxidizers offer performance gains over more benign oxidizers. Potential benefits were observed for gelled propellants that could be allowed to freeze, then thawed for use.

  7. Laser Ignition Technology for Bi-Propellant Rocket Engine Applications

    Science.gov (United States)

    Thomas, Matthew E.; Bossard, John A.; Early, Jim; Trinh, Huu; Dennis, Jay; Turner, James (Technical Monitor)

    2001-01-01

    The fiber optically coupled laser ignition approach summarized is under consideration for use in igniting bi-propellant rocket thrust chambers. This laser ignition approach is based on a novel dual pulse format capable of effectively increasing laser generated plasma life times up to 1000 % over conventional laser ignition methods. In the dual-pulse format tinder consideration here an initial laser pulse is used to generate a small plasma kernel. A second laser pulse that effectively irradiates the plasma kernel follows this pulse. Energy transfer into the kernel is much more efficient because of its absorption characteristics thereby allowing the kernel to develop into a much more effective ignition source for subsequent combustion processes. In this research effort both single and dual-pulse formats were evaluated in a small testbed rocket thrust chamber. The rocket chamber was designed to evaluate several bipropellant combinations. Optical access to the chamber was provided through small sapphire windows. Test results from gaseous oxygen (GOx) and RP-1 propellants are presented here. Several variables were evaluated during the test program, including spark location, pulse timing, and relative pulse energy. These variables were evaluated in an effort to identify the conditions in which laser ignition of bi-propellants is feasible. Preliminary results and analysis indicate that this laser ignition approach may provide superior ignition performance relative to squib and torch igniters, while simultaneously eliminating some of the logistical issues associated with these systems. Further research focused on enhancing the system robustness, multiplexing, and window durability/cleaning and fiber optic enhancements is in progress.

  8. Space shuttle auxiliary propulsion system design study. Phase C and E report: Storable propellants, RCS/OMS/APU integration study

    Science.gov (United States)

    Anglim, D. D.; Bruns, A. E.; Perryman, D. C.; Wieland, D. L.

    1972-01-01

    Auxiliary propulsion concepts for application to the space shuttle are compared. Both monopropellant and bipropellant earth storable reaction control systems were evaluated. The fundamental concepts evaluated were: (1) monopropellant and bipropellant systems installed integrally within the vehicle, (2) fuel systems installed modularly in nose and wing tip pods, and (3) fuel systems installed modularly in nose and fuselage pods. Numerous design variations within these three concepts were evaluated. The system design analysis and methods for implementing each of the concepts are reported.

  9. Study and Sub-System Optimization of Propulsion and Drive Systems for the Large Civil TiltRotor (LCTR2) Rotorcraft

    Science.gov (United States)

    Robuck, Mark; Wilkerson, Joseph; Snyder, Christopher A.; Zhang, Yiyi; Maciolek, Bob

    2013-01-01

    In a series of study tasks conducted as a part of NASA's Fundamental Aeronautics Program, Rotary Wing Project, Boeing and Rolls-Royce explored propulsion, drive, and rotor system options for the NASA Large Civil Tilt Rotor (LCTR2) concept vehicle. The original objective of this study was to identify engine and drive system configurations to reduce rotor tip speed during cruise conditions and quantify the associated benefits. Previous NASA studies concluded that reducing rotor speed (from 650 fps hover tip speed) during cruise would reduce vehicle gross weight and fuel burn. Initially, rotor cruise speed ratios of 54% of the hover tip speed were of most interest during operation at cruise air speed of 310 ktas. Interim results were previously reported1 for cruise tip speed ratios of 100%, 77%, and 54% of the hover tip speed using engine and/or gearbox features to achieve the reduction. Technology levels from commercial off-the-shelf (COTS), through entry-in-service (EIS) dates of 2025 and 2035 were considered to assess the benefits of advanced technology on vehicle gross weight and fuel burn. This technical paper presents the final study results in terms of vehicle sizing and fuel burn as well as Operational and Support (O&S) costs. New vehicle sizing at rotor tip speed reduced to 65% of hover is presented for engine performance with an EIS 2035 fixed geometry variable speed power turbine. LCTR2 is also evaluated for missions range cases of 400, 600, 800, 1000, and 1200 nautical miles and cruise air speeds of 310, 350 and 375 ktas.

  10. Advanced Chemical Propulsion for Science Missions

    Science.gov (United States)

    Liou, Larry

    2008-01-01

    The advanced chemical propulsion technology area of NASA's In-Space Technology Project is investing in systems and components for increased performance and reduced cost of chemical propulsion technologies applicable to near-term science missions. Presently the primary investment in the advanced chemical propulsion technology area is in the AMBR high temperature storable bipropellant rocket engine. Scheduled to be available for flight development starting in year 2008, AMBR engine shows a 60 kg payload gain in an analysis for the Titan-Enceladus orbiter mission and a 33 percent manufacturing cost reduction over its baseline, state-of-the-art counterpart. Other technologies invested include the reliable lightweight tanks for propellant and the precision propellant management and mixture ratio control. Both technologies show significant mission benefit, can be applied to any liquid propulsion system, and upon completion of the efforts described in this paper, are at least in parts ready for flight infusion. Details of the technologies are discussed.

  11. Materials Advance Chemical Propulsion Technology

    Science.gov (United States)

    2012-01-01

    In the future, the Planetary Science Division of NASA's Science Mission Directorate hopes to use better-performing and lower-cost propulsion systems to send rovers, probes, and observers to places like Mars, Jupiter, and Saturn. For such purposes, a new propulsion technology called the Advanced Materials Bipropellant Rocket (AMBR) was developed under NASA's In-Space Propulsion Technology (ISPT) project, located at Glenn Research Center. As an advanced chemical propulsion system, AMBR uses nitrogen tetroxide oxidizer and hydrazine fuel to propel a spacecraft. Based on current research and development efforts, the technology shows great promise for increasing engine operation and engine lifespan, as well as lowering manufacturing costs. In developing AMBR, ISPT has several goals: to decrease the time it takes for a spacecraft to travel to its destination, reduce the cost of making the propulsion system, and lessen the weight of the propulsion system. If goals like these are met, it could result in greater capabilities for in-space science investigations. For example, if the amount (and weight) of propellant required on a spacecraft is reduced, more scientific instruments (and weight) could be added to the spacecraft. To achieve AMBR s maximum potential performance, the engine needed to be capable of operating at extremely high temperatures and pressure. To this end, ISPT required engine chambers made of iridium-coated rhenium (strong, high-temperature metallic elements) that allowed operation at temperatures close to 4,000 F. In addition, ISPT needed an advanced manufacturing technique for better coating methods to increase the strength of the engine chamber without increasing the costs of fabricating the chamber.

  12. Experimental study on the thrust modulation performance of powdered magnesium and CO2 bipropellant engine

    Science.gov (United States)

    Li, Chao; Hu, Chunbo; Zhu, Xiaofei; Hu, Jiaming; Li, Yue; Hu, Xu

    2018-06-01

    Powdered Mg and CO2 bipropellant engine providing a practical demonstration of in situ resource utilization (ISRU) for Mars Sample Return (MSR) mission seems to be feasible by current investigations. However, essential functions of the engine to satisfy the complicated ballistics requirements such as thrust modulation and multiple pulse have not been established yet. The aim of this experimental study is to evaluate the engine's thrust modulation feasibility and to investigate its thrust modulation characteristics. A powdered Mg and CO2 bipropellant engine construction aiming to achieve thrust modulation ability was proposed. A mass flow rate calibration experiment to evaluate the gas-solid mass flow rate regulating performance was conducted before fire tests. Fire test result shows that the engine achieved successful ignition as well as self-sustaining combustion; Thrust modulation of the engine is feasible, detail thrust estimating result of the test shows that maximum thrust is 135.91 N and the minimum is 5.65 N with a 22.11 thrust modulation ratio, moreover, the transportation period is quick and the thrust modulation ratio is adjustable. At the same time, the powder feed system reaches a two-step flow rate regulating with a modulation ratio of 4.5-5. What' more, caused by the uneven engine working conditions, there is an obvious difference in combustion efficiency value, maximum combustion efficiency of the powdered Mg and CO2 bipropellant engine is 80.20%.

  13. 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...

  14. A Dual Mode Propulsion System for Small Satellite Applications

    Directory of Open Access Journals (Sweden)

    Kevin R. Gagne

    2018-05-01

    Full Text Available This study focused on the development of a chemical micropropulsion system suitable for primary propulsion and/or attitude control for a nanosatellite. Due to the limitations and expense of current micropropulsion technologies, few nanosatellites with propulsion have been launched to date; however, the availability of such a propulsion system would allow for new nanosatellite mission concepts, such as deep space exploration, maneuvering in low gravity environments and formation flying. This work describes the design of “dual mode” monopropellant/bipropellant microthruster prototype that employs a novel homogeneous catalysis scheme. Results from prototype testing are reported that validate the concept. The micropropulsion system is designed to be fabricated using a combination of additively-manufactured and commercial off the shelf (COTS parts along with non-toxic fuels, thus making it a low-cost and environmentally-friendly option for future nanosatellite missions.

  15. Space power subsystem sizing

    International Nuclear Information System (INIS)

    Geis, J.W.

    1992-01-01

    This paper discusses a Space Power Subsystem Sizing program which has been developed by the Aerospace Power Division of Wright Laboratory, Wright-Patterson Air Force Base, Ohio. The Space Power Subsystem program (SPSS) contains the necessary equations and algorithms to calculate photovoltaic array power performance, including end-of-life (EOL) and beginning-of-life (BOL) specific power (W/kg) and areal power density (W/m 2 ). Additional equations and algorithms are included in the spreadsheet for determining maximum eclipse time as a function of orbital altitude, and inclination. The Space Power Subsystem Sizing program (SPSS) has been used to determine the performance of several candidate power subsystems for both Air Force and SDIO potential applications. Trade-offs have been made between subsystem weight and areal power density (W/m 2 ) as influenced by orbital high energy particle flux and time in orbit

  16. Microchannel Thermo Catalytic Ignition for Advanced Mono- and Bipropellants, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Small and micro-spacecrafts require the efficient, micro-propulsion systems. Chemical micro-propulsion is best suited for use as primary thrust, orbital insertion...

  17. Virtual Quantum Subsystems

    International Nuclear Information System (INIS)

    Zanardi, Paolo

    2001-01-01

    The physical resources available to access and manipulate the degrees of freedom of a quantum system define the set A of operationally relevant observables. The algebraic structure of A selects a preferred tensor product structure, i.e., a partition into subsystems. The notion of compoundness for quantum systems is accordingly relativized. Universal control over virtual subsystems can be achieved by using quantum noncommutative holonomies

  18. Hot rocket plume experiment - Survey and conceptual design. [of rhenium-iridium bipropellants

    Science.gov (United States)

    Millard, Jerry M.; Luan, Taylor W.; Dowdy, Mack W.

    1992-01-01

    Attention is given to a space-borne engine plume experiment study to fly an experiment which will both verify and quantify the reduced contamination from advanced rhenium-iridium earth-storable bipropellant rockets (hot rockets) and provide a correlation between high-fidelity, in-space measurements and theoretical plume and surface contamination models. The experiment conceptual design is based on survey results from plume and contamination technologists throughout the U.S. With respect to shuttle use, cursory investigations validate Hitchhiker availability and adaptability, adequate remote manipulator system (RMS) articulation and dynamic capability, acceptable RMS attachment capability, adequate power and telemetry capability, and adequate flight altitude and attitude/orbital capability.

  19. CubeSat High Impulse Propulsion System (CHIPS), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — CU Aerospace proposes to perform design, fabrication, and ground test validation of a nanosat primary propulsion subsystem using non-toxic R134a propellant. Our...

  20. CubeSat High Impulse Propulsion System (CHIPS), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — CU Aerospace proposes the ground test validation of a nanosat primary propulsion subsystem using non-toxic propellant with 3-axis ACS for orbit change and/or...

  1. Titan I propulsion system modeling and possible performance improvements

    Science.gov (United States)

    Giusti, Oreste

    This thesis features the Titan I propulsion systems and offers data-supported suggestions for improvements to increase performance. The original propulsion systems were modeled both graphically in CAD and via equations. Due to the limited availability of published information, it was necessary to create a more detailed, secondary set of models. Various engineering equations---pertinent to rocket engine design---were implemented in order to generate the desired extra detail. This study describes how these new models were then imported into the ESI CFD Suite. Various parameters are applied to these imported models as inputs that include, for example, bi-propellant combinations, pressure, temperatures, and mass flow rates. The results were then processed with ESI VIEW, which is visualization software. The output files were analyzed for forces in the nozzle, and various results were generated, including sea level thrust and ISP. Experimental data are provided to compare the original engine configuration models to the derivative suggested improvement models.

  2. The NASA In-Space Propulsion Technology Project, Products, and Mission Applicability

    Science.gov (United States)

    Anderson, David J.; Pencil, Eric; Liou, Larry; Dankanich, John; Munk, Michelle M.; Kremic, Tibor

    2009-01-01

    The In-Space Propulsion Technology (ISPT) Project, funded by NASA s Science Mission Directorate (SMD), is continuing to invest in propulsion technologies that will enable or enhance NASA robotic science missions. This overview provides development status, near-term mission benefits, applicability, and availability of in-space propulsion technologies in the areas of aerocapture, electric propulsion, advanced chemical thrusters, and systems analysis tools. Aerocapture investments improved: guidance, navigation, and control models of blunt-body rigid aeroshells; atmospheric models for Earth, Titan, Mars, and Venus; and models for aerothermal effects. Investments in electric propulsion technologies focused on completing NASA s Evolutionary Xenon Thruster (NEXT) ion propulsion system, a 0.6 to 7 kW throttle-able gridded ion system. The project is also concluding its High Voltage Hall Accelerator (HiVHAC) mid-term product specifically designed for a low-cost electric propulsion option. The primary chemical propulsion investment is on the high-temperature Advanced Material Bipropellant Rocket (AMBR) engine providing higher performance for lower cost. The project is also delivering products to assist technology infusion and quantify mission applicability and benefits through mission analysis and tools. In-space propulsion technologies are applicable, and potentially enabling for flagship destinations currently under evaluation, as well as having broad applicability to future Discovery and New Frontiers mission solicitations.

  3. Propulsion system research and development for electric and hybrid vehicles

    Science.gov (United States)

    Schwartz, H. J.

    1980-01-01

    An approach to propulsion subsystem technology is presented. Various tests of component reliability are described to aid in the production of better quality vehicles. component characterization work is described to provide engineering data to manufacturers on component performance and on important component propulsion system interactions.

  4. 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.

  5. Liquid Rocket Propulsion for Atmospheric Flight in the Proposed ARES Mars Scout Mission

    Science.gov (United States)

    Kuhl, Christopher A.; Wright, Henry S.; Hunter, Craig A.; Guernsey, Carl S.; Colozza, Anthony J.

    2004-01-01

    Flying above the Mars Southern Highlands, an airplane will traverse over the terrain of Mars while conducting unique science measurements of the atmosphere, surface, and interior. This paper describes an overview of the ARES (Aerial Regional-scale Environmental Survey) mission with an emphasis on airplane propulsion needs. The process for selecting a propulsion system for the ARES airplane is also included. Details of the propulsion system, including system schematics, hardware and performance are provided. The airplane has a 6.25 m wingspan with a total mass of 149 kg and is propelled by a bi-propellant liquid rocket system capable of carrying roughly 48 kg of MMH/MON3 propellant.

  6. Spacecraft Design Thermal Control Subsystem

    Science.gov (United States)

    Miyake, Robert N.

    2008-01-01

    The Thermal Control Subsystem engineers task is to maintain the temperature of all spacecraft components, subsystems, and the total flight system within specified limits for all flight modes from launch to end-of-mission. In some cases, specific stability and gradient temperature limits will be imposed on flight system elements. The Thermal Control Subsystem of "normal" flight systems, the mass, power, control, and sensing systems mass and power requirements are below 10% of the total flight system resources. In general the thermal control subsystem engineer is involved in all other flight subsystem designs.

  7. A conceptual study of the use of a particle bed reactor nuclear propulsion module for the orbital maneuvering vehicle

    International Nuclear Information System (INIS)

    Malloy, J.; Potekhen, D.

    1989-01-01

    This paper examines the use of a particle bed reactor nuclear engine for direct thrust in a spacecraft based on the NASA/TRW orbital maneuvering vehicle (OMV). It presents the conceptual design of a 500 lb thrust engine that matches critical design features of the existing OMV bi-propellant propulsion system. This application contrasts with the usual tendency to consider a nuclear heat source either for high thrust direct propulsion or as a power source for electric propulsion. A nuclear propulsion module adapted to the OMV could potentially accomplish several Department of Defense missions, such as multiple round trips from a space-based support platform at 280 NM to service a constellation of satellites orbiting at 1800 NM

  8. Environmental Control Subsystem Development

    Science.gov (United States)

    Laidlaw, Jacob; Zelik, Jonathan

    2017-01-01

    Kennedy Space Center's Launch Pad 39B, part of Launch Complex 39, is currently undergoing construction to prepare it for NASA's Space Launch System missions. The Environmental Control Subsystem, which provides the vehicle with an air or nitrogen gas environment, required development of its local and remote display screens. The remote displays, developed by NASA contractors and previous interns, were developed without complete functionality; the remote displays were revised, adding functionality to over 90 displays. For the local displays, multiple test procedures were developed to assess the functionality of the screens, as well as verify requirements. One local display screen was also developed.

  9. Sadhana | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Reduction of costs is a main consideration in every space mission, and propulsion system is an important subsystem of those missions where orbital maneuvers are considered. Lighter propulsions with higher performance are necessary to reduce the mission costs. Bipropellant propulsions have been widely used in launch ...

  10. Evolution of magnetic disk subsystems

    Science.gov (United States)

    Kaneko, Satoru

    1994-06-01

    The higher recording density of magnetic disk realized today has brought larger storage capacity per unit and smaller form factors. If the required access performance per MB is constant, the performance of large subsystems has to be several times better. This article describes mainly the technology for improving the performance of the magnetic disk subsystems and the prospects of their future evolution. Also considered are 'crosscall pathing' which makes the data transfer channel more effective, 'disk cache' which improves performance coupling with solid state memory technology, and 'RAID' which improves the availability and integrity of disk subsystems by organizing multiple disk drives in a subsystem. As a result, it is concluded that since the performance of the subsystem is dominated by that of the disk cache, maximation of the performance of the disk cache subsystems is very important.

  11. Regional transmission subsystem planning

    Energy Technology Data Exchange (ETDEWEB)

    Costa Bortoni, Edson da [Quadrante Softwares Especializados Ltda., Itajuba, MG (Brazil); Bajay, Sergio Valdir; Barros Correia, Paulo de [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica; Santos, Afonso Henriques Moreira; Haddad, Jamil [Escola Federal de Engenharia de Itajuba, MG (Brazil)

    1994-12-31

    This work presents an approach for the planning of transmission systems by employing mixed--integer linear programming to obtain a cost and operating characteristics optimized system. The voltage loop equations are written in a modified form, so that, at the end of the analysis, the model behaves as a DC power flow, with the help of the two Kirchhoff`s laws, exempting the need of interaction with an external power flow program for analysis of the line loading. The model considers the occurrence of contingencies, so that the final result is a network robust to the most severe contingencies. This whole technique is adapted to the regional electric power transmission subsystems. (author) 9 refs., 4 figs.

  12. 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

  13. Distributed propulsion.

    OpenAIRE

    Lindström, Robin; Rosvall, Tobias

    2013-01-01

    En prestandaanalys utfördes på en SAAB 2000 som referensobjekt. Olika metoder för att driva flygplan på ett miljövänligare sätt utvärderades tillsammans med distributed propulsion. Efter undersökningar valdes elmotorer tillsammans med Zink-luft batterier för att driva SAAB 2000 med distributed propulsion. En prestandaanalys utfördes på detta plan på samma sätt som för den ursprungliga SAAB 2000. Resultaten jämfördes och slutsatsen blev att räckvidden var för kort för att konfigurationen skull...

  14. 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.

  15. Development costs for a nuclear electric propulsion stage.

    Science.gov (United States)

    Mondt, J. F.; Prickett, W. Z.

    1973-01-01

    Development costs are presented for an unmanned nuclear electric propulsion (NEP) stage based upon a liquid metal cooled, in-core thermionic reactor. A total of 120 kWe are delivered to the thrust subsystem which employs mercury ion engines for electric propulsion. This study represents the most recent cost evaluation of the development of a reactor power system for a wide range of nuclear space power applications. These include geocentric, and outer planet and other deep space missions. The development program is described for the total NEP stage, based upon specific development programs for key NEP stage components and subsystems.

  16. Propulsion Systems Panel deliberations

    Science.gov (United States)

    Bianca, Carmelo J.; Miner, Robert; Johnston, Lawrence M.; Bruce, R.; Dennies, Daniel P.; Dickenson, W.; Dreshfield, Robert; Karakulko, Walt; Mcgaw, Mike; Munafo, Paul M.

    1993-01-01

    The Propulsion Systems Panel was established because of the specialized nature of many of the materials and structures technology issues related to propulsion systems. This panel was co-chaired by Carmelo Bianca, MSFC, and Bob Miner, LeRC. Because of the diverse range of missions anticipated for the Space Transportation program, three distinct propulsion system types were identified in the workshop planning process: liquid propulsion systems, solid propulsion systems and nuclear electric/nuclear thermal propulsion systems.

  17. Electric vehicle propulsion alternatives

    Science.gov (United States)

    Secunde, R. R.; Schuh, R. M.; Beach, R. F.

    1983-01-01

    Propulsion technology development for electric vehicles is summarized. Analytical studies, technology evaluation, and the development of technology for motors, controllers, transmissions, and complete propulsion systems are included.

  18. Electric and hybrid vehicle environmental control subsystem study

    Science.gov (United States)

    Heitner, K. L.

    1980-01-01

    An environmental control subsystem (ECS) in electric and hybrid vehicles is studied. A combination of a combustion heater and gasoline engine (Otto cycle) driven vapor compression air conditioner is selected. The combustion heater, the small gasoline engine, and the vapor compression air conditioner are commercially available. These technologies have good cost and performance characteristics. The cost for this ECS is relatively close to the cost of current ECS's. Its effect on the vehicle's propulsion battery is minimal and the ECS size and weight do not have significant impact on the vehicle's range.

  19. In-Space Propulsion Technology Products for NASA's Future Science and Exploration Missions

    Science.gov (United States)

    Anderson, David J.; Pencil, Eric; Peterson, Todd; Dankanich, John; Munk, Michelle M.

    2011-01-01

    Since 2001, the In-Space Propulsion Technology (ISPT) project has been developing and delivering in-space propulsion technologies that will enable or enhance NASA robotic science missions. These in-space propulsion technologies are applicable, and potentially enabling, for future NASA flagship and sample return missions currently being considered, as well as having broad applicability to future competed mission solicitations. The high-temperature Advanced Material Bipropellant Rocket (AMBR) engine providing higher performance for lower cost was completed in 2009. Two other ISPT technologies are nearing completion of their technology development phase: 1) NASA's Evolutionary Xenon Thruster (NEXT) ion propulsion system, a 0.6-7 kW throttle-able gridded ion system; and 2) Aerocapture technology development with investments in a family of thermal protection system (TPS) materials and structures; guidance, navigation, and control (GN&C) models of blunt-body rigid aeroshells; aerothermal effect models: and atmospheric models for Earth, Titan, Mars and Venus. This paper provides status of the technology development, applicability, and availability of in-space propulsion technologies that have recently completed their technology development and will be ready for infusion into NASA s Discovery, New Frontiers, Science Mission Directorate (SMD) Flagship, and Exploration technology demonstration missions

  20. In-Space Propulsion Technology Products Ready for Infusion on NASA's Future Science Missions

    Science.gov (United States)

    Anderson, David J.; Pencil, Eric; Peterson, Todd; Dankanich, John; Munk, Michele M.

    2012-01-01

    Since 2001, the In-Space Propulsion Technology (ISPT) program has been developing and delivering in-space propulsion technologies that will enable or enhance NASA robotic science missions. These in-space propulsion technologies are applicable, and potentially enabling, for future NASA flagship and sample return missions currently being considered. They have a broad applicability to future competed mission solicitations. The high-temperature Advanced Material Bipropellant Rocket (AMBR) engine, providing higher performance for lower cost, was completed in 2009. Two other ISPT technologies are nearing completion of their technology development phase: 1) NASA s Evolutionary Xenon Thruster (NEXT) ion propulsion system, a 0.6-7 kW throttle-able gridded ion system; and 2) Aerocapture technology development with investments in a family of thermal protection system (TPS) materials and structures; guidance, navigation, and control (GN&C) models of blunt-body rigid aeroshells; aerothermal effect models; and atmospheric models for Earth, Titan, Mars and Venus. This paper provides status of the technology development, applicability, and availability of in-space propulsion technologies that have recently completed their technology development and will be ready for infusion into NASA s Discovery, New Frontiers, SMD Flagship, or technology demonstration missions.

  1. Spherical subsystem of galactic radiosources

    Energy Technology Data Exchange (ETDEWEB)

    Gorshkov, A G; Popov, M V [Moskovskij Gosudarstvennyj Univ. (USSR). Gosudarstvennyj Astronomicheskij Inst. ' ' GAISh' '

    1975-05-01

    The concentration of statistically complete sampling radiosources of the Ohiof scanning with plane spectra towards the Galaxy centre has been discovered. Quantitative calculations have showed that the sources form a spheric subsystem, which is close in parameters to such old formations in the Galaxy as globular clusters and the RRLsub(YR) type stars. The luminosity of the galaxy spheric subsystem object equals 10/sup 33/ erg/sec, the total number of objects being 7000. The existence of such a subsystem explains s the anomalously by low incline of statistics lgN-lgS in HF scanning PKS (..gamma..-2700Mgz) and the Michigan University scanning (..gamma..=8000Mgz) because the sources of galaxy spheric subsystem make up a considerable share in the total number of sources, especially at high frequencies (50% of sources with a flux greater than a unit of flux per 8000Mgz). It is very probable that the given subsystem consists of the representatives of one of the following class of objects: a) heat sources - the H2H regions with T=10/sup 40/K, Nsub(e)=10/sup 3/, l=1 ps b) supermass black holes with mass M/Mo approximately 10/sup 5/.

  2. Space power subsystem automation technology

    Science.gov (United States)

    Graves, J. R. (Compiler)

    1982-01-01

    The technology issues involved in power subsystem automation and the reasonable objectives to be sought in such a program were discussed. The complexities, uncertainties, and alternatives of power subsystem automation, along with the advantages from both an economic and a technological perspective were considered. Whereas most spacecraft power subsystems now use certain automated functions, the idea of complete autonomy for long periods of time is almost inconceivable. Thus, it seems prudent that the technology program for power subsystem automation be based upon a growth scenario which should provide a structured framework of deliberate steps to enable the evolution of space power subsystems from the current practice of limited autonomy to a greater use of automation with each step being justified on a cost/benefit basis. Each accomplishment should move toward the objectives of decreased requirement for ground control, increased system reliability through onboard management, and ultimately lower energy cost through longer life systems that require fewer resources to operate and maintain. This approach seems well-suited to the evolution of more sophisticated algorithms and eventually perhaps even the use of some sort of artificial intelligence. Multi-hundred kilowatt systems of the future will probably require an advanced level of autonomy if they are to be affordable and manageable.

  3. 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

  4. 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.)

  5. Status and Mission Applicability of NASA's In-Space Propulsion Technology Project

    Science.gov (United States)

    Anderson, David J.; Munk, Michelle M.; Dankanich, John; Pencil, Eric; Liou, Larry

    2009-01-01

    The In-Space Propulsion Technology (ISPT) project develops propulsion technologies that will enable or enhance NASA robotic science missions. Since 2001, the ISPT project developed and delivered products to assist technology infusion and quantify mission applicability and benefits through mission analysis and tools. These in-space propulsion technologies are applicable, and potentially enabling for flagship destinations currently under evaluation, as well as having broad applicability to future Discovery and New Frontiers mission solicitations. This paper provides status of the technology development, near-term mission benefits, applicability, and availability of in-space propulsion technologies in the areas of advanced chemical thrusters, electric propulsion, aerocapture, and systems analysis tools. The current chemical propulsion investment is on the high-temperature Advanced Material Bipropellant Rocket (AMBR) engine providing higher performance for lower cost. Investments in electric propulsion technologies focused on completing NASA's Evolutionary Xenon Thruster (NEXT) ion propulsion system, a 0.6-7 kW throttle-able gridded ion system, and the High Voltage Hall Accelerator (HiVHAC) thruster, which is a mid-term product specifically designed for a low-cost electric propulsion option. Aerocapture investments developed a family of thermal protections system materials and structures; guidance, navigation, and control models of blunt-body rigid aeroshells; atmospheric models for Earth, Titan, Mars and Venus; and models for aerothermal effects. In 2009 ISPT started the development of propulsion technologies that would enable future sample return missions. The paper describes the ISPT project's future focus on propulsion for sample return missions. The future technology development areas for ISPT is: Planetary Ascent Vehicles (PAV), with a Mars Ascent Vehicle (MAV) being the initial development focus; multi-mission technologies for Earth Entry Vehicles (MMEEV) needed

  6. Block storage subsystem performance analysis

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    You feel that your service is slow because of the storage subsystem? But there are too many abstraction layers between your software and the raw block device for you to debug all this pile... Let's dive on the platters and check out how the block storage sees your I/Os! We can even figure out what those patterns are meaning.

  7. Design of a Mars Airplane Propulsion System for the Aerial Regional-Scale Environmental Survey (ARES) Mission Concept

    Science.gov (United States)

    Kuhl, Christopher A.

    2008-01-01

    The Aerial Regional-Scale Environmental Survey (ARES) is a Mars exploration mission concept that utilizes a rocket propelled airplane to take scientific measurements of atmospheric, surface, and subsurface phenomena. The liquid rocket propulsion system design has matured through several design cycles and trade studies since the inception of the ARES concept in 2002. This paper describes the process of selecting a bipropellant system over other propulsion system options, and provides details on the rocket system design, thrusters, propellant tank and PMD design, propellant isolation, and flow control hardware. The paper also summarizes computer model results of thruster plume interactions and simulated flight performance. The airplane has a 6.25 m wingspan with a total wet mass of 185 kg and has to ability to fly over 600 km through the atmosphere of Mars with 45 kg of MMH / MON3 propellant.

  8. The USAF Electric Propulsion Program

    National Research Council Canada - National Science Library

    Spores, Ronald

    1999-01-01

    ...: Propulsion Directorate and Air Force Office of Scientific Research (AFOSR). The Propulsion Directorate conducts electric propulsion efforts in basic research, engineering development, and space experiments...

  9. Numerical investigation on liquid sheets interaction characteristics of liquid-liquid coaxial swirling jets in bipropellant thruster

    International Nuclear Information System (INIS)

    Ding, Jia-Wei; Li, Guo-Xiu; Yu, Yu-Song

    2016-01-01

    Highlights: • A LES-VOF model is conducted to simulate atomization of coaxial swirling jets. • Structure and flow field of coaxial swirling jets are investigated. • Merging process occurs at the nozzle exit and generates additional perturbation. • The Rayleigh mode instability dominates the breakup of ligaments. - Abstract: Spray atomization process of a liquid-liquid coaxial swirl injector in bipropellant thruster has been investigated using volume of fluid (VOF) method coupled with large eddy simulation methodology. With fine grid resolution, detailed flow field of interacted liquid sheet has been captured and analyzed. For coaxial swirling jet, static pressure drop in the region between the liquid sheets makes two liquid sheets to approach each other and merge. A strong pressure, velocity and turbulent fluctuations are calculated near the contact position of two coaxial jets. Simulation results indicate that additional perturbations are generated due to strong radial and axial shear effects between coaxial jets. Observation of droplet formation process reveals that the Rayleigh mode instability dominates the breakup of the ligament. Droplet diameter and distribution have been investigated quantitatively. The mean diameter of the coaxial jets is between that of the inner and the outer jets. Compared with the individual swirling jets, wider size distributions of droplets are produced in the coaxial jets.

  10. MITS Data Acquisition Subsystem Acceptance Test procedure

    International Nuclear Information System (INIS)

    Allison, R.

    1980-01-01

    This is an acceptance procedure for the Data Acquisition Subsystem of the Machine Interface Test System (MITS). Prerequisites, requirements, and detailed step-by-step instruction are presented for inspecting and performance testing the subsystem

  11. The Phenix Detector magnet subsystem

    International Nuclear Information System (INIS)

    Yamamoto, R.M.; Bowers, J.M.; Harvey, A.R.

    1995-01-01

    The PHENIX [Photon Electron New Heavy Ion Experiment] Detector is one of two large detectors presently under construction for RHIC (Relativistic Heavy Ion Collider) located at Brookhaven National Laboratory. Its primary goal is to detect a new phase of matter; the quark-gluon plasma. In order to achieve this objective, the PHENIX Detector utilizes a complex magnet subsystem which is comprised of two large magnets identified as the Central Magnet (CM) and the Muon Magnet (MM). Muon Identifier steel is also included as part of this package. The entire magnet subsystem stands over 10 meters tall and weighs in excess of 1900 tons (see Fig. 1). Magnet size alone provided many technical challenges throughout the design and fabrication of the project. In addition, interaction with foreign collaborators provided the authors with new areas to address and problems to solve. Russian collaborators would fabricate a large fraction of the steel required and Japanese collaborators would supply the first coil. This paper will describe the overall design of the PHENIX magnet subsystem and discuss its present fabrication status

  12. The Phenix Detector magnet subsystem

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, R.M.; Bowers, J.M.; Harvey, A.R. [Lawrence Livermore National Lab., CA (United States)] [and others

    1995-05-19

    The PHENIX [Photon Electron New Heavy Ion Experiment] Detector is one of two large detectors presently under construction for RHIC (Relativistic Heavy Ion Collider) located at Brookhaven National Laboratory. Its primary goal is to detect a new phase of matter; the quark-gluon plasma. In order to achieve this objective, the PHENIX Detector utilizes a complex magnet subsystem which is comprised of two large magnets identified as the Central Magnet (CM) and the Muon Magnet (MM). Muon Identifier steel is also included as part of this package. The entire magnet subsystem stands over 10 meters tall and weighs in excess of 1900 tons (see Fig. 1). Magnet size alone provided many technical challenges throughout the design and fabrication of the project. In addition, interaction with foreign collaborators provided the authors with new areas to address and problems to solve. Russian collaborators would fabricate a large fraction of the steel required and Japanese collaborators would supply the first coil. This paper will describe the overall design of the PHENIX magnet subsystem and discuss its present fabrication status.

  13. Evaluation of the use of on-board spacecraft energy storage for electric propulsion missions

    Science.gov (United States)

    Poeschel, R. L.; Palmer, F. M.

    1983-01-01

    On-board spacecraft energy storage represents an under utilized resource for some types of missions that also benefit from using relatively high specific impulse capability of electric propulsion. This resource can provide an appreciable fraction of the power required for operating the electric propulsion subsystem in some missions. The most probable mission requirement for utilization of this energy is that of geostationary satellites which have secondary batteries for operating at high power levels during eclipse. The study summarized in this report selected four examples of missions that could benefit from use of electric propulsion and on-board energy storage. Engineering analyses were performed to evaluate the mass saved and economic benefit expected when electric propulsion and on-board batteries perform some propulsion maneuvers that would conventionally be provided by chemical propulsion. For a given payload mass in geosynchronous orbit, use of electric propulsion in this manner typically provides a 10% reduction in spacecraft mass.

  14. Advanced Propulsion Study

    National Research Council Canada - National Science Library

    Davis, Eric

    2004-01-01

    ... that show promise of leading to a major advance in Earth-to-orbit (ETO) propulsion. The study also reviewed and evaluated a select number of credible far-term breakthrough propulsion physics concepts pertaining...

  15. Liquid Oxygen/Liquid Methane Integrated Power and Propulsion

    Science.gov (United States)

    Banker, Brian; Ryan, Abigail

    2016-01-01

    The proposed paper will cover ongoing work at the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) on integrated power and propulsion for advanced human exploration. Specifically, it will present findings of the integrated design, testing, and operational challenges of a liquid oxygen / liquid methane (LOx/LCH4) propulsion brassboard and Solid Oxide Fuel Cell (SOFC) system. Human-Mars architectures point to an oxygen-methane economy utilizing common commodities, scavenged from the planetary atmosphere and soil via In-Situ Resource Utilization (ISRU), and common commodities across sub-systems. Due to the enormous mass gear-ratio required for human exploration beyond low-earth orbit, (for every 1 kg of payload landed on Mars, 226 kg will be required on Earth) increasing commonality between spacecraft subsystems such as power and propulsion can result in tremendous launch mass and volume savings. Historically, propulsion and fuel cell power subsystems have had little interaction outside of the generation (fuel cell) and consumption (propulsion) of electrical power. This was largely due to a mismatch in preferred commodities (hypergolics for propulsion; oxygen & hydrogen for fuel cells). Although this stove-piped approach benefits from simplicity in the design process, it means each subsystem has its own tanks, pressurization system, fluid feed system, etc. increasing overall spacecraft mass and volume. A liquid oxygen / liquid methane commodities architecture across propulsion and power subsystems would enable the use of common tankage and associated pressurization and commodity delivery hardware for both. Furthermore, a spacecraft utilizing integrated power and propulsion could use propellant residuals - propellant which could not be expelled from the tank near depletion due to hydrodynamic considerations caused by large flow demands of a rocket engine - to generate power after all propulsive maneuvers are complete thus utilizing

  16. Status report on nuclear electric propulsion systems

    Science.gov (United States)

    Stearns, J. W.

    1975-01-01

    Progress in nuclear electric propulsion (NEP) systems for a multipayload multimission vehicle needed in both deep-space missions and a variety of geocentric missions is reviewed. The space system power level is a function of the initial launch vehicle mass, but developments in out-of-core nuclear thermionic direct conversion have broadened design options. Cost, design, and performance parameters are compared for reusable chemical space tugs and NEP reusable space tugs. Improvements in heat pipes, ion engines, and magnetoplasmadynamic arc jet thrust subsystems are discussed.

  17. FY2015 Propulsion Materials Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2016-12-30

    The Propulsion Materials Program actively supports the energy security and reduction of greenhouse emissions goals of VTO by investigating and identifying the materials properties that are most essential for continued development of cost-effective, highly efficient, and environmentally friendly next-generation heavy and light-duty powertrains. The technical approaches available to enhance propulsion systems focus on improvements in both vehicle efficiency and fuel substitution, both of which must overcome the performance limitations of the materials currently in use. Propulsion Materials Program activities work with national laboratories, industry experts, and VTO powertrain systems (e.g., Advanced Combustion Engines [ACE], Advanced Power Electronics and Electrical Machines [APEEM], and fuels) teams to develop strategies that overcome materials limitations in future powertrain performance. The technical maturity of the portfolio of funded projects ranges from basic science to subsystem prototype validation. Projects within a Propulsion Materials Program activity address materials concerns that directly impact critical technology barriers within each of the above programs, including barriers that impact fuel efficiency, thermal management, emissions reduction, improved reliability, and reduced manufacturing costs. The program engages only the barriers that result from material property limitations and represent fundamental, high-risk materials issues.

  18. FY2016 Propulsion Materials Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-05-01

    The Propulsion Materials Program actively supports the energy security and reduction of greenhouse emissions goals of VTO by investigating and identifying the materials properties that are most essential for continued development of cost-effective, highly efficient, and environmentally friendly next-generation heavy and light-duty powertrains. The technical approaches available to enhance propulsion systems focus on improvements in both vehicle efficiency and fuel substitution, both of which must overcome the performance limitations of the materials currently in use. Propulsion Materials Program activities work with national laboratories, industry experts, and VTO powertrain systems (e.g., Advanced Combustion Engines and Fuels) teams to develop strategies that overcome materials limitations in future powertrain performance. The technical maturity of the portfolio of funded projects ranges from basic science to subsystem prototype validation. Projects within a Propulsion Materials Program activity address materials concerns that directly impact critical technology barriers within each of the above programs, including barriers that impact fuel efficiency, thermal management, emissions reduction, improved reliability, and reduced manufacturing costs. The program engages only the barriers that result from material property limitations and represent fundamental, high-risk materials issues.

  19. Centralized versus distributed propulsion

    Science.gov (United States)

    Clark, J. P.

    1982-01-01

    The functions and requirements of auxiliary propulsion systems are reviewed. None of the three major tasks (attitude control, stationkeeping, and shape control) can be performed by a collection of thrusters at a single central location. If a centralized system is defined as a collection of separated clusters, made up of the minimum number of propulsion units, then such a system can provide attitude control and stationkeeping for most vehicles. A distributed propulsion system is characterized by more numerous propulsion units in a regularly distributed arrangement. Various proposed large space systems are reviewed and it is concluded that centralized auxiliary propulsion is best suited to vehicles with a relatively rigid core. These vehicles may carry a number of flexible or movable appendages. A second group, consisting of one or more large flexible flat plates, may need distributed propulsion for shape control. There is a third group, consisting of vehicles built up from multiple shuttle launches, which may be forced into a distributed system because of the need to add additional propulsion units as the vehicles grow. The effects of distributed propulsion on a beam-like structure were examined. The deflection of the structure under both translational and rotational thrusts is shown as a function of the number of equally spaced thrusters. When two thrusters only are used it is shown that location is an important parameter. The possibility of using distributed propulsion to achieve minimum overall system weight is also examined. Finally, an examination of the active damping by distributed propulsion is described.

  20. Tools for advanced simulations to nuclear propulsion systems in rockets

    International Nuclear Information System (INIS)

    Torres Sepulveda, A.; Perez Vara, R.

    2004-01-01

    While chemical propulsion rockets have dominated space exploration, other forms of rocket propulsion based on nuclear power, electrostatic and magnetic drive, and other principles besides chemical reactions, have been considered from the earliest days of the field. The goal of most of these advanced rocket propulsion schemes is improved efficiency through higher exhaust velocities, in order to reduce the amount of fuel the rocket vehicle needs to carry, though generally at the expense of high thrust. Nuclear propulsion seems to be the most promising short term technology to plan realistic interplanetary missions. The development of a nuclear electric propulsion spacecraft shall require the development of models to analyse the mission and to understand the interaction between the related subsystems (nuclear reactor, electrical converter, power management and distribution, and electric propulsion) during the different phases of the mission. This paper explores the modelling of a nuclear electric propulsion (NEP) spacecraft type using EcosimPro simulation software. This software is a multi-disciplinary simulation tool with a powerful object-oriented simulation language and state-of-the-art solvers. EcosimPro is the recommended ESA simulation tool for environmental Control and Life Support Systems (ECLSS) and has been used successfully within the framework of the European activities of the International Space Station programme. Furthermore, propulsion libraries for chemical and electrical propulsion are currently being developed under ESA contracts to set this tool as standard usage in the propulsion community. At present, there is not any workable NEP spacecraft, but a standardized-modular, multi-purpose interplanetary spacecraft for post-2000 missions, called ISC-2000, has been proposed in reference. The simulation model presented on this paper is based on the preliminary designs for this spacecraft. (Author)

  1. Cassini Mission Sequence Subsystem (MSS)

    Science.gov (United States)

    Alland, Robert

    2011-01-01

    This paper describes my work with the Cassini Mission Sequence Subsystem (MSS) team during the summer of 2011. It gives some background on the motivation for this project and describes the expected benefit to the Cassini program. It then introduces the two tasks that I worked on - an automatic system auditing tool and a series of corrections to the Cassini Sequence Generator (SEQ_GEN) - and the specific objectives these tasks were to accomplish. Next, it details the approach I took to meet these objectives and the results of this approach, followed by a discussion of how the outcome of the project compares with my initial expectations. The paper concludes with a summary of my experience working on this project, lists what the next steps are, and acknowledges the help of my Cassini colleagues.

  2. Operationally Responsive Spacecraft Subsystem, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Saber Astronautics proposes spacecraft subsystem control software which can autonomously reconfigure avionics for best performance during various mission conditions....

  3. Nuclear propulsion for orbital transfer

    International Nuclear Information System (INIS)

    Beale, G.A.; Lawrence, T.J.

    1989-01-01

    The state of the art in nuclear propulsion for orbital transfer is discussed. Cryogenic propulsion, electric propulsion, solar-thermal propulsion and direct nuclear propulsion are examined in this context. New technologies with exceptional promise are addressed, emphasizing the particle test bed nuclear engine

  4. Catalyzed Combustion In Micro-Propulsion Devices: Project Status

    Science.gov (United States)

    Sung, C. J.; Schneider, S. J.

    2003-01-01

    the basic units, or in a rapid sequence in order to provide gradual but steady low-g acceleration. These arrays of micro-propulsion systems would offer unprecedented flexibility and redundancy for satellite propulsion and reaction control for launch vehicles. A high-pressure bi-propellant micro-rocket engine is already being developed using MEMS technology. High pressure turbopumps and valves are to be incorporated onto the rocket chip . High pressure combustion of methane and O2 in a micro-combustor has been demonstrated without catalysis, but ignition was established with a spark. This combustor has rectangular dimensions of 1.5 mm by 8 mm (hydraulic diameter 3.9 mm) and a length of 4.5 mm and was operated at 1250 kPa with plans to operate it at 12.7 MPa. These high operating pressures enable the combustion process in these devices, but these pressures are not practical for pressure fed satellite propulsion systems. Note that the use of these propellants requires an ignition system and that the use of a spark would impose a size limitation to this micro-propulsion device because the spark unit cannot be shrunk proportionately with the thruster. Results presented in this paper consist of an experimental evaluation of the minimum catalyst temperature for initiating/supporting combustion in sub-millimeter diameter tubes. The tubes are resistively heated and reactive premixed gases are passed through the tubes. Tube temperature and inlet pressure are monitored for an indication of exothermic reactions and composition changes in the gases.

  5. National Ignition Facility subsystem design requirements target positioning subsystem SSDR 1.8.2

    International Nuclear Information System (INIS)

    Pittenger, L.

    1996-01-01

    This Subsystem Design Requirement document is a development specification that establishes the performance, design, development and test requirements for the target positioner subsystem (WBS 1.8.2) of the NIF Target Experimental System (WBS 1.8)

  6. 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.

  7. Information Subsystem of Shadow Economy Deactivation

    OpenAIRE

    Filippova, Tatyana V.

    2015-01-01

    The article presents information subsystem of shadow economy deactivation aimed at minimizing negative effects caused by its reproduction. In Russia, as well as in other countries, efficient implementation of the suggested system of shadow economy deactivation can be ensured by the developed information subsystem.

  8. Installation package for the Solaron solar subsystem

    Science.gov (United States)

    1979-01-01

    Information that is intended to be a guide for installation, operation, and maintenance of the various solar subsystems is presented. The subsystems consist of the following: collectors, storage, transport (air handler) and controller for heat pump and peak storage. Two prototype residential systems were installed at Akron, Ohio, and Duffield, Virginia.

  9. Private quantum subsystems and quasiorthogonal operator algebras

    International Nuclear Information System (INIS)

    Levick, Jeremy; Kribs, David W; Pereira, Rajesh; Jochym-O’Connor, Tomas; Laflamme, Raymond

    2016-01-01

    We generalize a recently discovered example of a private quantum subsystem to find private subsystems for Abelian subgroups of the n-qubit Pauli group, which exist in the absence of private subspaces. In doing so, we also connect these quantum privacy investigations with the theory of quasiorthogonal operator algebras through the use of tools from group theory and operator theory. (paper)

  10. NASA's Propulsion Research Laboratory

    Science.gov (United States)

    2004-01-01

    The grand opening of NASA's new, world-class laboratory for research into future space transportation technologies located at the Marshall Space Flight Center (MSFC) in Huntsville, Alabama, took place in July 2004. The state-of-the-art Propulsion Research Laboratory (PRL) serves as a leading national resource for advanced space propulsion research. Its purpose is to conduct research that will lead to the creation and development of innovative propulsion technologies for space exploration. The facility is the epicenter of the effort to move the U.S. space program beyond the confines of conventional chemical propulsion into an era of greatly improved access to space and rapid transit throughout the solar system. The laboratory is designed to accommodate researchers from across the United States, including scientists and engineers from NASA, the Department of Defense, the Department of Energy, universities, and industry. The facility, with 66,000 square feet of useable laboratory space, features a high degree of experimental capability. Its flexibility allows it to address a broad range of propulsion technologies and concepts, such as plasma, electromagnetic, thermodynamic, and propellant propulsion. An important area of emphasis is the development and utilization of advanced energy sources, including highly energetic chemical reactions, solar energy, and processes based on fission, fusion, and antimatter. The Propulsion Research Laboratory is vital for developing the advanced propulsion technologies needed to open up the space frontier, and sets the stage of research that could revolutionize space transportation for a broad range of applications.

  11. 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

  12. Response of subsystems on inelastic structures

    International Nuclear Information System (INIS)

    Lin, J.; Mahin, S.A.

    1984-01-01

    Preliminary analysis are performed to obtain insight into the seismic response of subsystems supported on simple structures that yield during severe earthquake ground motions. Current design recommendations for subsystems accounting for yielding of the supporting structures are assessed and found to be unconservative. An amplification factor is defined to quantify the effects of inelastic deformations of the supporting structure on subsystem response. Design guidelines are formulated for predicting the amplification factor based on statistical evaluation of the results generated for ten earthquake ground motions. Using these values, design floor response spectra can be obtained from conventional linear elastic floor response spectra accounting for yielding of the supporting structure without having to perform inelastic analysis. The effects of non-zero subsystem mass are examined. The recommended amplification factors are found to be applicable even when the mass of subsystem approaches that of the supporting structure

  13. Efficient chaotic based satellite power supply subsystem

    International Nuclear Information System (INIS)

    Ramos Turci, Luiz Felipe; Macau, Elbert E.N.; Yoneyama, Takashi

    2009-01-01

    In this work, we investigate the use of the Dynamical System Theory to increase the efficiency of the satellite power supply subsystems. The core of a satellite power subsystem relies on its DC/DC converter. This is a very nonlinear system that presents a multitude of phenomena ranging from bifurcations, quasi-periodicity, chaos, coexistence of attractors, among others. The traditional power subsystem design techniques try to avoid these nonlinear phenomena so that it is possible to use linear system theory in small regions about the equilibrium points. Here, we show that more efficiency can be drawn from a power supply subsystem if the DC/DC converter operates in regions of high nonlinearity. In special, if it operates in a chaotic regime, is has an intrinsic sensitivity that can be exploited to efficiently drive the power subsystem over high ranges of power requests by using control of chaos techniques.

  14. Efficient chaotic based satellite power supply subsystem

    Energy Technology Data Exchange (ETDEWEB)

    Ramos Turci, Luiz Felipe [Technological Institute of Aeronautics (ITA), Sao Jose dos Campos, SP (Brazil)], E-mail: felipeturci@yahoo.com.br; Macau, Elbert E.N. [National Institute of Space Research (Inpe), Sao Jose dos Campos, SP (Brazil)], E-mail: elbert@lac.inpe.br; Yoneyama, Takashi [Technological Institute of Aeronautics (ITA), Sao Jose dos Campos, SP (Brazil)], E-mail: takashi@ita.br

    2009-10-15

    In this work, we investigate the use of the Dynamical System Theory to increase the efficiency of the satellite power supply subsystems. The core of a satellite power subsystem relies on its DC/DC converter. This is a very nonlinear system that presents a multitude of phenomena ranging from bifurcations, quasi-periodicity, chaos, coexistence of attractors, among others. The traditional power subsystem design techniques try to avoid these nonlinear phenomena so that it is possible to use linear system theory in small regions about the equilibrium points. Here, we show that more efficiency can be drawn from a power supply subsystem if the DC/DC converter operates in regions of high nonlinearity. In special, if it operates in a chaotic regime, is has an intrinsic sensitivity that can be exploited to efficiently drive the power subsystem over high ranges of power requests by using control of chaos techniques.

  15. ECCS Operability With One or More Subsystem(s) Inoperable

    International Nuclear Information System (INIS)

    Swantner, Stephen R.; Andrachek, James D.

    2002-01-01

    equivalent to a single Operable ECCS train exists with those components out of service. This evaluation ensures that the safety analysis assumption associated with one train of emergency core cooling system (ECCS) is still preserved by various combinations of components in opposite trains. An ECCS train is inoperable if it is not capable of delivering design flow to the reactor coolant system (RCS). Individual components are inoperable of they are not capable of performing their design function, or support systems are not available. Due to the redundancy of trains and the diversity of subsystems, the inoperability of one component in a train does render the ECCS incapable of performing its function. Neither does the inoperability of two different components, each in a different train, necessarily result in a loss of function for the ECCS. The intent of Condition A is to maintain a combination of components such that 100% of the ECCS flow equivalent to a single Operable ECCS train remains available. This allows increased flexibility in plant operations under circumstances when components in the required subsystem may be inoperable, but the ECCS remains capable of delivering 100% of the required flow equivalent. This paper presents a methodology for identifying the minimum set of components necessary for 100% of the ECCS flow equivalent to a single Operable ECCS train. An example of the implementation of this methodology is provided for a typical Westinghouse 3-loop ECCS design. (authors)

  16. Laser Propulsion - Quo Vadis

    International Nuclear Information System (INIS)

    Bohn, Willy L.

    2008-01-01

    First, an introductory overview of the different types of laser propulsion techniques will be given and illustrated by some historical examples. Second, laser devices available for basic experiments will be reviewed ranging from low power lasers sources to inertial confinement laser facilities. Subsequently, a status of work will show the impasse in which the laser propulsion community is currently engaged. Revisiting the basic relations leads to new avenues in ablative and direct laser propulsion for ground based and space based applications. Hereby, special attention will be devoted to the impact of emerging ultra-short pulse lasers on the coupling coefficient and specific impulse. In particular, laser sources and laser propulsion techniques will be tested in microgravity environment. A novel approach to debris removal will be discussed with respect to the Satellite Laser Ranging (SRL) facilities. Finally, some non technical issues will be raised aimed at the future prospects of laser propulsion in the international community

  17. ACCESS Sub-system Performance

    Science.gov (United States)

    Kaiser, Mary Elizabeth; Morris, Matthew J.; Aldoroty, Lauren Nicole; Godon, David; Pelton, Russell; McCandliss, Stephan R.; Kurucz, Robert L.; Kruk, Jeffrey W.; Rauscher, Bernard J.; Kimble, Randy A.; Wright, Edward L.; Benford, Dominic J.; Gardner, Jonathan P.; Feldman, Paul D.; Moos, H. Warren; Riess, Adam G.; Bohlin, Ralph; Deustua, Susana E.; Dixon, William Van Dyke; Sahnow, David J.; Lampton, Michael; Perlmutter, Saul

    2016-01-01

    ACCESS: Absolute Color Calibration Experiment for Standard Stars is a series of rocket-borne sub-orbital missions and ground-based experiments designed to leverage significant technological advances in detectors, instruments, and the precision of the fundamental laboratory standards used to calibrate these instruments to enable improvements in the precision of the astrophysical flux scale through the transfer of laboratory absolute detector standards from the National Institute of Standards and Technology (NIST) to a network of stellar standards with a calibration accuracy of 1% and a spectral resolving power of 500 across the 0.35 to 1.7 micron bandpass.A cross wavelength calibration of the astrophysical flux scale to this level of precision over this broad a bandpass is relevant for the data used to probe fundamental astrophysical problems such as the SNeIa photometry based measurements used to constrain dark energy theories.We will describe the strategy for achieving this level of precision, the payload and calibration configuration, present sub-system test data, and the status and preliminary performance of the integration and test of the spectrograph and telescope. NASA APRA sounding rocket grant NNX14AH48G supports this work.

  18. The Calipso Thermal Control Subsystem

    Science.gov (United States)

    Gasbarre, Joseph F.; Ousley, Wes; Valentini, Marc; Thomas, Jason; Dejoie, Joel

    2007-01-01

    The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) is a joint NASA-CNES mission to study the Earth s cloud and aerosol layers. The satellite is composed of a primary payload (built by Ball Aerospace) and a spacecraft platform bus (PROTEUS, built by Alcatel Alenia Space). The thermal control subsystem (TCS) for the CALIPSO satellite is a passive design utilizing radiators, multi-layer insulation (MLI) blankets, and both operational and survival surface heaters. The most temperature sensitive component within the satellite is the laser system. During thermal vacuum testing of the integrated satellite, the laser system s operational heaters were found to be inadequate in maintaining the lasers required set point. In response, a solution utilizing the laser system s survival heaters to augment the operational heaters was developed with collaboration between NASA, CNES, Ball Aerospace, and Alcatel-Alenia. The CALIPSO satellite launched from Vandenberg Air Force Base in California on April 26th, 2006. Evaluation of both the platform and payload thermal control systems show they are performing as expected and maintaining the critical elements of the satellite within acceptable limits.

  19. 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.

  20. Data Transport Subsystem - The SFOC glue

    Science.gov (United States)

    Parr, Stephen J.

    1988-01-01

    The design and operation of the Data Transport Subsystem (DTS) for the JPL Space Flight Operation Center (SFOC) are described. The SFOC is the ground data system under development to serve interplanetary space probes; in addition to the DTS, it comprises a ground interface facility, a telemetry-input subsystem, data monitor and display facilities, and a digital TV system. DTS links the other subsystems via an ISO OSI presentation layer and an LAN. Here, particular attention is given to the DTS services and service modes (virtual circuit, datagram, and broadcast), the DTS software architecture, the logical-name server, the role of the integrated AI library, and SFOC as a distributed system.

  1. Research, development, and demonstration of lead-acid batteries for electric vehicle propulsion. Annual report, 1980

    Energy Technology Data Exchange (ETDEWEB)

    1981-03-01

    The progress and status of Eltra's Electric Vehicle Battery Program during FY-80 are presented under five divisional headings: Research on Components and Processes; Development of Cells and Modules for Electric Vehicle Propulsion; Sub-Systems; Pilot Line Production of Electric Vehicle Battery Prototypes; and Program Management.

  2. Structural modeling and fuzzy-logic based diagnosis of a ship propulsion benchmark

    DEFF Research Database (Denmark)

    Izadi-Zamanabadi, Roozbeh; Blanke, M.; Katebi, S.D.

    2000-01-01

    An analysis of structural model of a ship propulsion benchmark leads to identifying the subsystems with inherent redundant information. For a nonlinear part of the system, a Fuzzy logic based FD algorithm with adaptive threshold is employed. The results illustrate the applicability of structural...

  3. Advanced Chemical Propulsion

    Science.gov (United States)

    Bai, S. Don

    2000-01-01

    Design, propellant selection, and launch assistance for advanced chemical propulsion system is discussed. Topics discussed include: rocket design, advance fuel and high energy density materials, launch assist, and criteria for fuel selection.

  4. 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.

  5. 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.)

  6. Distributed propulsion for ships

    OpenAIRE

    Nylund, Vilde

    2017-01-01

    It is anticipated that using distributed electric propulsion (DEP) on conventional ships will increase the total propulsive efficiency. This is mainly due to two reasons; firstly, because the total propeller disk area can be increased. Secondly, because each propeller can be optimised for the local wake where it is operating. In this work, the benefits of using DEP has been investigated for a 14 000 TEU container ship. Based on a literary study of the present state of propeller modelling ...

  7. Wheelchairs propulsion analysis: review

    Directory of Open Access Journals (Sweden)

    Yoshimasa Sagawa Júnior

    Full Text Available OBJECTIVES: To analyze aspects related with wheelchair propulsion. MATERIALS AND METHODS: In order to delineate this review the search for information was carried out within electronics databases, using the following descriptors: "wheelchair propulsion", "wheelchair biomechanics" e "wheelchair users". Full papers published in English and French were included in the study. RESULTS: The wheelchair propulsion is a complex movement that requires the execution of repeated bi manual forces applications during a short time period. In this movement high levels of force must be produced due to the bad mechanical performance of the wheelchair. Could be characterized that wheelchair users are not satisfied with their wheelchair, the places are not adapted to their presence and lack of specific criteria for the adjustment of this equipment. The main points to look at are the seat height in relation to elbow flexion (100-120 degrees with his hand in the propulsion rim and tire pressure. The semicircular mode of technique propulsion seems to be more appropriate; in this pattern the wheelchair user returns his hand under the rim after propulsion. Efforts in wheelchairs are high and the incidence of injuries in wheelchair users is high. CONCLUSION: One can conclude that in spite of researchers’ efforts there are still many divergences between topics and methods of evaluation, what makes difficult to apply the experimental results to the wheelchairs users’ daily life.

  8. Fuel Effective Photonic Propulsion

    Science.gov (United States)

    Rajalakshmi, N.; Srivarshini, S.

    2017-09-01

    With the entry of miniaturization in electronics and ultra-small light-weight materials, energy efficient propulsion techniques for space travel can soon be possible. We need to go for such high speeds so that the generation’s time long interstellar missions can be done in incredibly short time. Also renewable energy like sunlight, nuclear energy can be used for propulsion instead of fuel. These propulsion techniques are being worked on currently. The recently proposed photon propulsion concepts are reviewed, that utilize momentum of photons generated by sunlight or onboard photon generators, such as blackbody radiation or lasers, powered by nuclear or solar power. With the understanding of nuclear photonic propulsion, in this paper, a rough estimate of nuclear fuel required to achieve the escape velocity of Earth is done. An overview of the IKAROS space mission for interplanetary travel by JAXA, that was successful in demonstrating that photonic propulsion works and also generated additional solar power on board, is provided; which can be used as a case study. An extension of this idea for interstellar travel, termed as ‘Star Shot’, aims to send a nanocraft to an exoplanet in the nearest star system, which could be potentially habitable. A brief overview of the idea is presented.

  9. Ion Beam Propulsion Study

    Science.gov (United States)

    2008-01-01

    The Ion Beam Propulsion Study was a joint high-level study between the Applied Physics Laboratory operated by NASA and ASRC Aerospace at Kennedy Space Center, Florida, and Berkeley Scientific, Berkeley, California. The results were promising and suggested that work should continue if future funding becomes available. The application of ion thrusters for spacecraft propulsion is limited to quite modest ion sources with similarly modest ion beam parameters because of the mass penalty associated with the ion source and its power supply system. Also, the ion source technology has not been able to provide very high-power ion beams. Small ion beam propulsion systems were used with considerable success. Ion propulsion systems brought into practice use an onboard ion source to form an energetic ion beam, typically Xe+ ions, as the propellant. Such systems were used for steering and correction of telecommunication satellites and as the main thruster for the Deep Space 1 demonstration mission. In recent years, "giant" ion sources were developed for the controlled-fusion research effort worldwide, with beam parameters many orders of magnitude greater than the tiny ones of conventional space thruster application. The advent of such huge ion beam sources and the need for advanced propulsion systems for exploration of the solar system suggest a fresh look at ion beam propulsion, now with the giant fusion sources in mind.

  10. Periodic subsystem density-functional theory

    International Nuclear Information System (INIS)

    Genova, Alessandro; Pavanello, Michele; Ceresoli, Davide

    2014-01-01

    By partitioning the electron density into subsystem contributions, the Frozen Density Embedding (FDE) formulation of subsystem Density Functional Theory (DFT) has recently emerged as a powerful tool for reducing the computational scaling of Kohn–Sham DFT. To date, however, FDE has been employed to molecular systems only. Periodic systems, such as metals, semiconductors, and other crystalline solids have been outside the applicability of FDE, mostly because of the lack of a periodic FDE implementation. To fill this gap, in this work we aim at extending FDE to treat subsystems of molecular and periodic character. This goal is achieved by a dual approach. On one side, the development of a theoretical framework for periodic subsystem DFT. On the other, the realization of the method into a parallel computer code. We find that periodic FDE is capable of reproducing total electron densities and (to a lesser extent) also interaction energies of molecular systems weakly interacting with metallic surfaces. In the pilot calculations considered, we find that FDE fails in those cases where there is appreciable density overlap between the subsystems. Conversely, we find FDE to be in semiquantitative agreement with Kohn–Sham DFT when the inter-subsystem density overlap is low. We also conclude that to make FDE a suitable method for describing molecular adsorption at surfaces, kinetic energy density functionals that go beyond the GGA level must be employed

  11. Periodic subsystem density-functional theory

    Science.gov (United States)

    Genova, Alessandro; Ceresoli, Davide; Pavanello, Michele

    2014-11-01

    By partitioning the electron density into subsystem contributions, the Frozen Density Embedding (FDE) formulation of subsystem Density Functional Theory (DFT) has recently emerged as a powerful tool for reducing the computational scaling of Kohn-Sham DFT. To date, however, FDE has been employed to molecular systems only. Periodic systems, such as metals, semiconductors, and other crystalline solids have been outside the applicability of FDE, mostly because of the lack of a periodic FDE implementation. To fill this gap, in this work we aim at extending FDE to treat subsystems of molecular and periodic character. This goal is achieved by a dual approach. On one side, the development of a theoretical framework for periodic subsystem DFT. On the other, the realization of the method into a parallel computer code. We find that periodic FDE is capable of reproducing total electron densities and (to a lesser extent) also interaction energies of molecular systems weakly interacting with metallic surfaces. In the pilot calculations considered, we find that FDE fails in those cases where there is appreciable density overlap between the subsystems. Conversely, we find FDE to be in semiquantitative agreement with Kohn-Sham DFT when the inter-subsystem density overlap is low. We also conclude that to make FDE a suitable method for describing molecular adsorption at surfaces, kinetic energy density functionals that go beyond the GGA level must be employed.

  12. Propellant Gelation for Green In-Space Propulsion, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Concerns in recent years about the toxicity and safe handling of the storable class of propellants have led to efforts in greener monopropellants and bi-propellants....

  13. NASA's nuclear thermal propulsion technology project

    International Nuclear Information System (INIS)

    Peecook, K.M.; Stone, J.R.

    1992-07-01

    The nonnuclear subsystem technologies required for incorporating nuclear thermal propulsion (NTP) into space-exploration missions are discussed. Of particular interest to planned missions are such technologies as materials, instrumentation and controls, turbomachinery, CFD modeling, nozzle extension designs and models, and analyses of exhaust plumes. NASA studies are described and/or proposed for refractory metals and alloys, robotic NTP controls, and turbopump materials candidates. Alternative nozzle concepts such as aerospikes and truncated plugs are proposed, and numerical simulations are set forth for studying heavy molecules and the backstreaming of highly reactive free-radical hydrogen in the exhaust plume. The critical technologies described in the paper are central to the development of NTP, and NTP has the potential to facilitate a range of space exploration activities. 3 refs

  14. The evaluation subsystem of RODOS

    International Nuclear Information System (INIS)

    Niculae, C.; Treitz, M.; Geldermann, J.

    2003-01-01

    Full text: The evaluation subsystem (ESY) of the RODOS aims to rank countermeasure strategies according to their potential benefit and preference weights provided by the decision makers (DMS). In the previous version of the ESY, the structure of the decision problem (attributes, strategies, etc.) had to be largely defined by the early modules in the RODOS chain (ASY-CSYESY). For this reason, the ESY runs would be initiated with a list of strategies, a comprehensive attribute tree and a consequence table giving the impacts for each attribute under each strategy. The first sub-module of the ESY allows the user to select the attributes to be analyzed and then filters out the remaining attributes. For instance, the CSY module LCMT passes over 100 attributes to the ESY, from which one would expect the analyst/DMS to select maybe 10 to 15 for the evaluation. This sub-module also adds a sub-tree of subjective attributes (qualitative information) to the attribute tree provided by the CSY and allows the user to select which of these should be passed forward for further analysis. In addition, data from the economic and health modules (e.g. costs, health effects, etc.) can be grafted on as a sub-tree. The second sub-module performs the ranking of the alternative strategies and outputs a short list of best strategies. The last component of the ESY contains an explanation facility that uses a fine set of rules to reason about the ranking of the strategies. Due to the complexity of the nuclear emergency management and the wide range of DMS and stakeholders involved in the decision process, it is difficult to predetermine the range of strategies they will consider. The current strategies or groups of strategies included in the system are only driven by radiological factors. Research in the field of multicriteria decision aid has shown that value focused approaches could result in new sets of alternatives, new criteria to be considered or different decision tree structures

  15. Embedded Thermal Control for Spacecraft Subsystems Miniaturization

    Science.gov (United States)

    Didion, Jeffrey R.

    2014-01-01

    Optimization of spacecraft size, weight and power (SWaP) resources is an explicit technical priority at Goddard Space Flight Center. Embedded Thermal Control Subsystems are a promising technology with many cross cutting NSAA, DoD and commercial applications: 1.) CubeSatSmallSat spacecraft architecture, 2.) high performance computing, 3.) On-board spacecraft electronics, 4.) Power electronics and RF arrays. The Embedded Thermal Control Subsystem technology development efforts focus on component, board and enclosure level devices that will ultimately include intelligent capabilities. The presentation will discuss electric, capillary and hybrid based hardware research and development efforts at Goddard Space Flight Center. The Embedded Thermal Control Subsystem development program consists of interrelated sub-initiatives, e.g., chip component level thermal control devices, self-sensing thermal management, advanced manufactured structures. This presentation includes technical status and progress on each of these investigations. Future sub-initiatives, technical milestones and program goals will be presented.

  16. 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).

  17. 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.

  18. 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.

  19. Timing subsystem development: Network synchronization experiments

    Science.gov (United States)

    Backe, K. R.

    1983-01-01

    This paper describes a program in which several experimental timing subsystem prototypes were designed, fabricated, and field tested using a small network of troposcatter and microwave digital communication links. This equipment was responsible for modem/radio interfacing, time interval measurement, clock adjustment and distribution, synchronization technique, and node to node information exchange. Presented are discussions of the design approach, measurement plan, and performance assessment methods. Recommendations are made based on the findings of the test program and an evaluation of the design of both the hardware and software elements of the timing subsystem prototypes.

  20. Lasing without inversion due to cooling subsystem

    International Nuclear Information System (INIS)

    Shakhmuratov, R.N.

    1997-01-01

    The new possibility of inversionless lasing is discussed. We have considered the resonant interaction of a two-level system (TLS) with photons and the adiabatic interaction with an ensemble of Bose particles. It is found out that a TLS with equally populated energy levels amplifies the coherent light with Stokes-shifted frequency. This becomes possible as photon emission is accompanied by Bose particles excitation. The energy flow from the TLS to the photon subsystem is realized due to the Bose subsystem being at finite temperature and playing the cooler role. The advantage of this new lasing principle is discussed. It is shown that lasing conditions strongly differ from conventional ones

  1. Multiple NEO Rendezvous Using Solar Sail Propulsion

    Science.gov (United States)

    Johnson, Les; Alexander, Leslie; Fabisinski, Leo; Heaton, Andy; Miernik, Janie; Stough, Rob; Wright, Roosevelt; Young, Roy

    2012-01-01

    The NASA Marshall Space Flight Center (MSFC) Advanced Concepts Office performed an assessment of the feasibility of using a near-term solar sail propulsion system to enable a single spacecraft to perform serial rendezvous operations at multiple Near Earth Objects (NEOs) within six years of launch on a small-to-moderate launch vehicle. The study baselined the use of the sail technology demonstrated in the mid-2000 s by the NASA In-Space Propulsion Technology Project and is scheduled to be demonstrated in space by 2014 as part of the NASA Technology Demonstration Mission Program. The study ground rules required that the solar sail be the only new technology on the flight; all other spacecraft systems and instruments must have had previous space test and qualification. The resulting mission concept uses an 80-m X 80-m 3-axis stabilized solar sail launched by an Athena-II rocket in 2017 to rendezvous with 1999 AO10, Apophis and 2001 QJ142. In each rendezvous, the spacecraft will perform proximity operations for approximately 30 days. The spacecraft science payload is simple and lightweight; it will consist of only the multispectral imager flown on the Near Earth Asteroid Rendezvous (NEAR) mission to 433 Eros and 253 Mathilde. Most non-sail spacecraft systems are based on the Messenger mission spacecraft. This paper will describe the objectives of the proposed mission, the solar sail technology to be employed, the spacecraft system and subsystems, as well as the overall mission profile.

  2. Solar Sail Propulsion Technology Readiness Level Database

    Science.gov (United States)

    Adams, Charles L.

    2004-01-01

    The NASA In-Space Propulsion Technology (ISPT) Projects Office has been sponsoring 2 solar sail system design and development hardware demonstration activities over the past 20 months. Able Engineering Company (AEC) of Goleta, CA is leading one team and L Garde, Inc. of Tustin, CA is leading the other team. Component, subsystem and system fabrication and testing has been completed successfully. The goal of these activities is to advance the technology readiness level (TRL) of solar sail propulsion from 3 towards 6 by 2006. These activities will culminate in the deployment and testing of 20-meter solar sail system ground demonstration hardware in the 30 meter diameter thermal-vacuum chamber at NASA Glenn Plum Brook in 2005. This paper will describe the features of a computer database system that documents the results of the solar sail development activities to-date. Illustrations of the hardware components and systems, test results, analytical models, relevant space environment definition and current TRL assessment, as stored and manipulated within the database are presented. This database could serve as a central repository for all data related to the advancement of solar sail technology sponsored by the ISPT, providing an up-to-date assessment of the TRL of this technology. Current plans are to eventually make the database available to the Solar Sail community through the Space Transportation Information Network (STIN).

  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. Modeling of Ship Propulsion Performance

    DEFF Research Database (Denmark)

    Pedersen, Benjamin Pjedsted; Larsen, Jan

    2009-01-01

    Full scale measurements of the propulsion power, ship speed, wind speed and direction, sea and air temperature, from four different loading conditions has been used to train a neural network for prediction of propulsion power. The network was able to predict the propulsion power with accuracy...

  5. 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…

  6. Reactors. Nuclear propulsion ships

    International Nuclear Information System (INIS)

    Fribourg, Ch.

    2001-01-01

    This article has for object the development of nuclear-powered ships and the conception of the nuclear-powered ship. The technology of the naval propulsion P.W.R. type reactor is described in the article B.N.3 141 'Nuclear Boilers ships'. (N.C.)

  7. Experimental evaluation of the IP multimedia subsystem

    NARCIS (Netherlands)

    Oredope, A.; Liotta, A.; Yang, K.; Tyrode-Goilo, D.H.; Magedanz, T.; Mauro Madeira, E.R.M.; Dini, P.

    2005-01-01

    The IP Multimedia Subsystem (IMS) is the latest framework for a seamless conversion of the ordinary Internet with mobile cellular systems. As such it has the backing of all major companies since it aims to offer a unified solution to integrated mobile services, including mechanisms for security,

  8. MITS Feed and Withdrawal Subsystem: operating procedures

    International Nuclear Information System (INIS)

    Brown, W.S.

    1980-01-01

    This procedure details the steps involved in establishing closed loop flows, providing UF 6 vapor to the FEED header of the Sampling Subsystem and returning it through the PRODUCT and TAILS headers via the F and W recycle valves. It is essentially a Startup Procedure

  9. Union Listing via OCLC's Serials Control Subsystem.

    Science.gov (United States)

    O'Malley, Terrence J.

    1984-01-01

    Describes library use of Conversion of Serials Project's (CONSER) online national machine-readable database for serials to create online union lists of serials via OCLC's Serial Control Subsystem. Problems in selection of appropriate, accurate, and authenticated records and prospects for the future are discussed. Twenty sources and sample records…

  10. Accelerated life testing of spacecraft subsystems

    Science.gov (United States)

    Wiksten, D.; Swanson, J.

    1972-01-01

    The rationale and requirements for conducting accelerated life tests on electronic subsystems of spacecraft are presented. A method for applying data on the reliability and temperature sensitivity of the parts contained in a sybsystem to the selection of accelerated life test parameters is described. Additional considerations affecting the formulation of test requirements are identified, and practical limitations of accelerated aging are described.

  11. Integrating the autonomous subsystems management process

    Science.gov (United States)

    Ashworth, Barry R.

    1992-01-01

    Ways in which the ranking of the Space Station Module Power Management and Distribution testbed may be achieved and an individual subsystem's internal priorities may be managed within the complete system are examined. The application of these results in the integration and performance leveling of the autonomously managed system is discussed.

  12. MITS Feed and Withdrawal Subsystem: operating procedures

    International Nuclear Information System (INIS)

    Brown, W.S.

    1980-01-01

    This document details procedures for the operation of the MITS (Machine Interface Test System) Feed and Withdrawal Subsystem (F and W). Included are fill with UF 6 , establishment of recycle and thruput flows, shutdown, UF 6 makeup, dump to supply container, Cascade dump to F and W, and lights cold trap dump, all normal procedures, plus an alternate procedure for trapping light gases

  13. Analog subsystem for the plutonium protection system

    International Nuclear Information System (INIS)

    Arlowe, H.D.

    1978-12-01

    An analog subsystem is described which monitors certain functions in the Plutonium Protection System. Rotary and linear potentiometer output signals are digitized, as are the outputs from thermistors and container ''bulge'' sensors. This work was sponsored by the Department of Energy/Office of Safeguards and Security (DOE/OSS) as part of the overall Sandia Fixed Facility Physical Protection Program

  14. MITS Feed and Withdrawal Subsystem: operating procedures

    International Nuclear Information System (INIS)

    Brown, W.S.

    1980-01-01

    This procedure details the steps involved in filling two of the four MITS (Machine Interface Test System) Feed and Withdrawal subsystem main traps and the Sample/Inventory Make-up Pipette with uranium hexafluoride from the ''AS RECEIVED'' UF 6 supply

  15. Presence in the IP multimedia subsystem

    NARCIS (Netherlands)

    Lin, L.; Liotta, A.

    2007-01-01

    With an ever increasing penetration of Internet Protocol (IP) technologies, the wireless industry is evolving the mobile core network towards all-IP network. The IP Multimedia Subsystem (IMS) is a standardised Next Generation Network (NGN) architectural framework defined by the 3rd Generation

  16. Electronic Subsystems For Laser Communication System

    Science.gov (United States)

    Long, Catherine; Maruschak, John; Patschke, Robert; Powers, Michael

    1992-01-01

    Electronic subsystems of free-space laser communication system carry digital signals at 650 Mb/s over long distances. Applicable to general optical communications involving transfer of great quantities of data, and transmission and reception of video images of high definition.

  17. Interlibrary Loan Communications Subsystem: Users Manual.

    Science.gov (United States)

    OCLC Online Computer Library Center, Inc., Dublin, OH.

    The OCLC Interlibrary Loan (ILL) Communications Subsystem provides participating libraries with on-line control of ILL transactions. This user manual includes a glossary of terms related to the procedures in using the system. Sections describe computer entry, searching, loan request form, loan response form, ILL procedures, the special message…

  18. National Ingition Facility subsystem design requirements optics subsystems SSDR 1.6

    International Nuclear Information System (INIS)

    English, R.E.

    1996-01-01

    This Subsystems Design Requirement (SSDR) document specifies the functions to be performed and the subsystems design requirements for the major optical components. These optical components comprise those custom designed and fabricated for amplification and transport of the full aperture NIF beam and does not include those off-the-shelf components that may be part of other optical sub-systems (i.e. alignment or diagnostic systems). This document also describes the optical component processing requirements and the QA/damage testing necessary to ensure that the optical components meet or exceed the requirements

  19. Dynamic analysis and design of air spring mounting system for marine propulsion system

    Science.gov (United States)

    He, Lin; Xu, Wei; Bu, Wenjun; Shi, Liang

    2014-09-01

    Marine propulsion unit (MPU) is one of the dominant vibration and noise sources onboard ship. Its vibration can be attenuated effectively by isolating MPU with low-frequency mounting system. But this is difficult to implement due to the stringent requirement of MPU alignment with the propulsion shafting. In this paper a novel air spring mounting system (ASMS) for propulsion system is proposed consisting of air spring subsystem, alignment control subsystem and safety protection subsystem. The load distribution optimization method and dynamic model of ASMS are presented. The factors that affect system stability and natural frequencies are analyzed, as well as the design measures to enhance system performance. A theoretical model is presented to estimate the isolation effect of ASMS. The monitoring model of alignment between MPU and propulsion shafting is established, followed by the alignment control algorithm and converge rule which assures the fast and uniform convergence of both air springs load distribution and alignment control process. Safety protection mechanism is designed to ensure that the MPU can operate safely in case of ASMS failure or other extreme circumstances. A scaled ASMS prototype is manufactured and tested on a special experimental setup. Experimental results validate the effectiveness of theoretical models and show that the performance of ASMS satisfies the operation requirements of MPU.

  20. Nuclear merchant ship propulsion

    International Nuclear Information System (INIS)

    Schroeder, E.; Jager, W.; Schafstall, H.G.

    1977-01-01

    The operation of about 300 nuclear naval vessels has proven the feasibility of nuclear ship propulsion. Until now six non military ships have been built or are under construction. In the Soviet Union two nuclear icebreakers are in operation, and a third one is under construction. In the western world three prototype merchant ships have been built. Of these ships only the NS OTTO HAHN is in operation and provides valuable experience for future large scale use of nuclear merchant ship propulsion. In many countries studies and plans are made for future nuclear merchant ships. Types of vessels investigated are large containerships, tankers and specialized ships like icebreakers or ice-breaking ships. The future of nuclear merchant ship propulsion depends on three interrelated items: (1) nuclear ship technology; (2) economy of nuclear ship propulsion; (3) legal questions. Nuclear merchant ship technology is based until now on standard ship technology and light water reactor technology. Except for special questions due to the non-stationary type of the plant entirely new problems do not arise. This has been proven by the recent conceptual licensing procedure for a large nuclear containership in Germany. The economics of nuclear propulsion will be under discussion until they are proven by the operation of privately owned lead ships. Unsolved legal questions e.g. in connection with port entry permissions are at present another problem for nuclear shipping. Efforts are made to solve these questions on an international basis. The future development of nuclear energy electricity production in large land based plants will stimulate the employment of smaller units. Any future development of long distance sea transport will have to take this opportunity of a reliable and economic energy supply into account

  1. Fusion propulsion systems

    International Nuclear Information System (INIS)

    Haloulakos, V.E.; Bourque, R.F.

    1989-01-01

    The continuing and expanding national efforts in both the military and commercial sectors for exploration and utilization of space will require launch, assembly in space, and orbital transfer of large payloads. The currently available delivery systems, utilizing various forms of chemical propulsion, do not have the payload capacity to fulfill the planned missions. National planning documents such as Air Force Project Forecast II and the National Commission on Space Report to the President contain numerous missions and payload delivery schedules that are beyond the present capabilities of the available systems, such as the Space Shuttle and the Expendable Launch Vehicles (ELVs). The need, therefore, is very pressing to design, develop, and deploy propulsion systems that offer a quantum level increase in delivered performance. One such potential system is fusion propulsion. This paper summarizes the result of an Air Force Astronautics Laboratory (AFAL) sponsored study of fusion propulsion conducted by the McDonnell Douglas Astronautics Company (MDAC), and its subcontractor General Atomics This study explored the potential of fusion propulsion for Air Force missions. Fusion fuels and existing confinement concepts were evaluated according to elaborate criteria. Two fuels, deuterium-tritium and deuterium-helium 3 (D- 3 He) were considered worthy of further consideration. D- 3 He was selected as the most attractive for this Air Force study. The colliding translating compact torus confinement concept was evaluated in depth and found to possibly possess the low mass and compactness required. Another possible concept is inertial confinement with the propellant surrounding the target. 5 refs., 5 figs., 8 tabs

  2. Evaluation of solar electric propulsion technologies for discovery class missions

    Science.gov (United States)

    Oh, David Y.

    2005-01-01

    A detailed study examines the potential benefits that advanced electric propulsion (EP) technologies offer to the cost-capped missions in NASA's Discovery program. The study looks at potential cost and performance benefits provided by three EP technologies that are currently in development: NASA's Evolutionary Xenon Thruster (NEXT), an Enhanced NSTAR system, and a Low Power Hall effect thruster. These systems are analyzed on three straw man Discovery class missions and their performance is compared to a state of the art system using the NSTAR ion thruster. An electric propulsion subsystem cost model is used to conduct a cost-benefit analysis for each option. The results show that each proposed technology offers a different degree of performance and/or cost benefit for Discovery class missions.

  3. Mars ascent propulsion options for small sample return vehicles

    International Nuclear Information System (INIS)

    Whitehead, J. C.

    1997-01-01

    An unprecedented combination of high propellant fraction and small size is required for affordable-scale Mars return, regardless of the number of stages, or whether Mars orbit rendezvous or in-situ propellant options are used. Conventional space propulsion technology is too heavy, even without structure or other stage subsystems. The application of launch vehicle design principles to the development of new hardware on a tiny scale is therefore suggested. Miniature pump-fed rocket engines fed by low pressure tanks can help to meet this challenge. New concepts for engine cycles using piston pumps are described, and development issues are outlined

  4. “You can get there from here”: Advanced low cost propulsion concepts for small satellites beyond LEO

    Science.gov (United States)

    Baker, Adam M.; da Silva Curiel, Alex; Schaffner, Jake; Sweeting, Martin

    2005-07-01

    microsatellite from a typical 700 km sun-synchronous orbit to a lower or higher orbit using a low cost 40 N thrust concentrated hydrogen peroxide/kerosene bipropellant engine. A spin stabilized 'tug' concept capable of providing between 130 and 300 m/s of deltaV to the payload is described. Transfer of an enhanced microsatellite from LEO to lunar orbit using a novel, storable propellant solar thermal propulsion system under development at the Surrey Space Centre. The solar thermal propulsion unit is designed for low cost small satellite support and will be compared with a more traditional approach using and industry standard storable bipropellant chemical engine. Nanosatellite manoeuvring for formation flying using advanced low power electric propulsion. A colloid thruster system concept is planned for development jointly between SSTL, Queen Mary University London and Rutherford Appleton Laboratory, UK. The colloid thruster system is designed to complement an existing butane resistojet to give full 3-axis manoeuvrability to an upgraded SNAP nanosatellite platform which could be reflown in 2007 alongside ESA's Proba 2 technology demonstrator microsatellite. A comparison between low power resistojets, a colloid thruster system, and pulsed plasma thrusters for orbit manoeuvring of microsatellites will be made. This paper's final section will briefly describe some of the interplanetary missions which have been considered at the Surrey Space Centre, and will highlight the few as yet practical solutions for sending small spacecraft on high deltaV missions without the use of a costly upper stage.

  5. FY2014 Propulsion Materials R&D Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-05-01

    The Propulsion Materials Program actively supports the energy security and reduction of greenhouse emissions goals of VTO by investigating and identifying the materials properties that are most essential for continued development of cost-effective, highly efficient, and environmentally friendly next-generation heavy and light-duty powertrains. The technical approaches available to enhance propulsion systems focus on improvements in both vehicle efficiency and fuel substitution, both of which must overcome the performance limitations of the materials currently in use. Propulsion Materials Program activities work with national laboratories, industry experts, and VTO powertrain systems (e.g., Advanced Combustion Engines [ACE], Advanced Power Electronics and Electrical Machines [APEEM], and fuels) teams to develop strategies that overcome materials limitations in future powertrain performance. The technical maturity of the portfolio of funded projects ranges from basic science to subsystem prototype validation. Projects within a Propulsion Materials Program activity address materials concerns that directly impact critical technology barriers within each of the above programs, including barriers that impact fuel efficiency, thermal management, emissions reduction, improved reliability, and reduced manufacturing costs. The program engages only the barriers that result from material property limitations and represent fundamental, high-risk materials issues.

  6. Advanced transportation system studies, technical area 3. Alternate propulsion subsystem concepts: J-2S restart study

    Science.gov (United States)

    Vilja, John; Levack, Daniel

    1993-04-01

    The objectives were to assess what design changes would be required to remit late production of the J-2S engine for use as a large high energy upper stage engine. The study assessed design changes required to perform per the J-2S model specification, manufacturing changes required due to obsolescence or improvements in state-of-the-practice, availability issues for supplier provided items, and provided cost and schedule estimates for this configuration. The confidence that J-2S production could be reinitiated within reasonable costs and schedules was provided. No significant technical issues were identified in either the producibility study or in the review of previous technical data. Areas of potential cost reduction were identified which could be quantified to a greater extent with further manufacturing planning. The proposed schedule can be met with no foreseeable impacts. The results of the study provided the necessary foundation for the detailed manufacturing and test plans and non-recurring and recurring cost estimates that are needed to complete the effort to reinitiate production of the J-2S engine system.

  7. MIT/Draper Technology Development Partnership Project: Systems Analysis and On-Station Propulsion Subsystem Design

    National Research Council Canada - National Science Library

    Conklin, Theodore

    1998-01-01

    The objective of this thesis is to describe the process for, and the overall design that resulted from the MIT/Draper Project from August, 1996 to May, 1997, including the specific design of the on...

  8. CFD for hypersonic propulsion

    Science.gov (United States)

    Povinelli, Louis A.

    1991-01-01

    An overview is given of research activity on the application of computational fluid dynamics (CDF) for hypersonic propulsion systems. After the initial consideration of the highly integrated nature of air-breathing hypersonic engines and airframe, attention is directed toward computations carried out for the components of the engine. A generic inlet configuration is considered in order to demonstrate the highly three dimensional viscous flow behavior occurring within rectangular inlets. Reacting flow computations for simple jet injection as well as for more complex combustion chambers are then discussed in order to show the capability of viscous finite rate chemical reaction computer simulations. Finally, the nozzle flow fields are demonstrated, showing the existence of complex shear layers and shock structure in the exhaust plume. The general issues associated with code validation as well as the specific issue associated with the use of CFD for design are discussed. A prognosis for the success of CFD in the design of future propulsion systems is offered.

  9. 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.

  10. 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.

  11. 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.

  12. Maintenance and operations cost model for DSN subsystems

    Science.gov (United States)

    Burt, R. W.; Lesh, J. R.

    1977-01-01

    A procedure is described which partitions the recurring costs of the Deep Space Network (DSN) over the individual DSN subsystems. The procedure results in a table showing the maintenance, operations, sustaining engineering and supportive costs for each subsystems.

  13. Partitioning a macroscopic system into independent subsystems

    Science.gov (United States)

    Delle Site, Luigi; Ciccotti, Giovanni; Hartmann, Carsten

    2017-08-01

    We discuss the problem of partitioning a macroscopic system into a collection of independent subsystems. The partitioning of a system into replica-like subsystems is nowadays a subject of major interest in several fields of theoretical and applied physics. The thermodynamic approach currently favoured by practitioners is based on a phenomenological definition of an interface energy associated with the partition, due to a lack of easily computable expressions for a microscopic (i.e. particle-based) interface energy. In this article, we outline a general approach to derive sharp and computable bounds for the interface free energy in terms of microscopic statistical quantities. We discuss potential applications in nanothermodynamics and outline possible future directions.

  14. Analysis on Sealing Reliability of Bolted Joint Ball Head Component of Satellite Propulsion System

    Science.gov (United States)

    Guo, Tao; Fan, Yougao; Gao, Feng; Gu, Shixin; Wang, Wei

    2018-01-01

    Propulsion system is one of the important subsystems of satellite, and its performance directly affects the service life, attitude control and reliability of the satellite. The Paper analyzes the sealing principle of bolted joint ball head component of satellite propulsion system and discuss from the compatibility of hydrazine anhydrous and bolted joint ball head component, influence of ground environment on the sealing performance of bolted joint ball heads, and material failure caused by environment, showing that the sealing reliability of bolted joint ball head component is good and the influence of above three aspects on sealing of bolted joint ball head component can be ignored.

  15. RF subsystem design for microwave communication receivers

    Science.gov (United States)

    Bickford, W. J.; Brodsky, W. G.

    A system review of the RF subsystems of (IFF) transponders, tropscatter receivers and SATCOM receivers is presented. The quantity potential for S-band and X-band IFF transponders establishes a baseline requirement. From this, the feasibility of a common design for these and other receivers is evaluated. Goals are established for a GaAs MMIC (monolithic microwave integrated circuit) device and related local oscillator preselector and self-test components.

  16. Optical Subsystems for Next Generation Access Networks

    DEFF Research Database (Denmark)

    Lazaro, J.A; Polo, V.; Schrenk, B.

    2011-01-01

    Recent optical technologies are providing higher flexibility to next generation access networks: on the one hand, providing progressive FTTx and specifically FTTH deployment, progressively shortening the copper access network; on the other hand, also opening fixed-mobile convergence solutions...... in next generation PON architectures. It is provided an overview of the optical subsystems developed for the implementation of the proposed NG-Access Networks....

  17. T Plant removal of PWR Chiller Subsystem

    International Nuclear Information System (INIS)

    Dana, C.M.

    1994-01-01

    The PWR Pool Chiller System is not longer required for support of the Shippingport Blanket Fuel Assemblies Storage. The Engineering Work Plan will provide the overall coordination of the documentation and physical changes to deactivate the unneeded subsystem. The physical removal of all energy sources for the Chiller equipment will be covered under a one time work plan. The documentation changes will be covered using approved Engineering Change Notices and Procedure Change Authorizations as needed

  18. The charged particle accelerators subsystems modeling

    International Nuclear Information System (INIS)

    Averyanov, G P; Kobylyatskiy, A V

    2017-01-01

    Presented web-based resource for information support the engineering, science and education in Electrophysics, containing web-based tools for simulation subsystems charged particle accelerators. Formulated the development motivation of Web-Environment for Virtual Electrophysical Laboratories. Analyzes the trends of designs the dynamic web-environments for supporting of scientific research and E-learning, within the framework of Open Education concept. (paper)

  19. Recent Advances in Airframe-Propulsion Concepts with Distributed Propulsion

    OpenAIRE

    Isikveren , A.T.; Seitz , A.; Bijewitz , J.; Hornung , M.; Mirzoyan , A.; Isyanov , A.; Godard , J.L.; Stückl , S.; Van Toor , J.

    2014-01-01

    International audience; This paper discusses design and integration associated with distributed propulsion as a means of providing motive power for future aircraft concepts. The technical work reflects activities performed within a European Commission funded Framework 7 project entitled Distributed Propulsion and Ultra-high By-Pass Rotor Study at Aircraft Level, or, DisPURSAL. In this instance, the approach of distributed propulsion includes one unique solution that integrates the fuselage wi...

  20. Stepping-Motion Motor-Control Subsystem For Testing Bearings

    Science.gov (United States)

    Powers, Charles E.

    1992-01-01

    Control subsystem closed-loop angular-position-control system causing motor and bearing under test to undergo any of variety of continuous or stepping motions. Also used to test bearing-and-motor assemblies, motors, angular-position sensors including rotating shafts, and like. Monitoring subsystem gathers data used to evaluate performance of bearing or other article under test. Monitoring subsystem described in article, "Monitoring Subsystem For Testing Bearings" (GSC-13432).

  1. 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

  2. Automated searching for quantum subsystem codes

    International Nuclear Information System (INIS)

    Crosswhite, Gregory M.; Bacon, Dave

    2011-01-01

    Quantum error correction allows for faulty quantum systems to behave in an effectively error-free manner. One important class of techniques for quantum error correction is the class of quantum subsystem codes, which are relevant both to active quantum error-correcting schemes as well as to the design of self-correcting quantum memories. Previous approaches for investigating these codes have focused on applying theoretical analysis to look for interesting codes and to investigate their properties. In this paper we present an alternative approach that uses computational analysis to accomplish the same goals. Specifically, we present an algorithm that computes the optimal quantum subsystem code that can be implemented given an arbitrary set of measurement operators that are tensor products of Pauli operators. We then demonstrate the utility of this algorithm by performing a systematic investigation of the quantum subsystem codes that exist in the setting where the interactions are limited to two-body interactions between neighbors on lattices derived from the convex uniform tilings of the plane.

  3. 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.

  4. Maglev for fast regional transportation. Optimization of long stator propulsion and energy supply; Magnetschnellbahn fuer den schnellen Regionalverkehr. Optimierung des Langstatorantriebs und der Energieversorgung

    Energy Technology Data Exchange (ETDEWEB)

    Fischperer, R.

    2006-07-01

    This work deals with linear propulsion systems of the Transrapid maglev system especially applicable to regional transportation tasks. In a first step the principle of the linear motor and its configurations and layout strategies for long distance applications are explained and analyzed with regard to their operational characteristics. Next, modified requirements for regional transportation are identified and strategies for optimization of the propulsion system are set up. Various optimization measures within the propulsion system and neighboring subsystems are worked out and explained. Finally, a quantitative analysis of different measures is shown using an exemplary regional line. Optimization potentials compared to a long distance propulsion layouts are shown. It has been found that given the relevant developments in the subsystems concerned savings of up to 40% both in investment and operation costs are feasible. (orig.)

  5. Space reactor system and subsystem investigations: assessment of technology issues for the reactor and shield subsystem. SP-100 Program

    International Nuclear Information System (INIS)

    Atkins, D.F.; Lillie, A.F.

    1983-01-01

    As part of Rockwell's effort on the SP-100 Program, preliminary assessment has been completed of current nuclear technology as it relates to candidate reactor/shield subsystems for the SP-100 Program. The scope of the assessment was confined to the nuclear package (to the reactor and shield subsystems). The nine generic reactor subsystems presented in Rockwell's Subsystem Technology Assessment Report, ESG-DOE-13398, were addressed for the assessment

  6. 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...

  7. 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.

  8. 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

  9. Space-reactor electric systems: subsystem technology assessment

    International Nuclear Information System (INIS)

    Anderson, R.V.; Bost, D.; Determan, W.R.

    1983-01-01

    This report documents the subsystem technology assessment. For the purpose of this report, five subsystems were defined for a space reactor electric system, and the report is organized around these subsystems: reactor; shielding; primary heat transport; power conversion and processing; and heat rejection. The purpose of the assessment was to determine the current technology status and the technology potentials for different types of the five subsystems. The cost and schedule needed to develop these potentials were estimated, and sets of development-compatible subsystems were identified

  10. 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

  11. 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

  12. National Ignition Facility subsystem design requirements target area auxiliary subsystem SSDR 1.8.6

    International Nuclear Information System (INIS)

    Reitz, T.

    1996-01-01

    This Subsystem Design Requirement (SSDR) establishes the performance, design, development, and test requirements for the Target Area Auxiliary Subsystems (WBS 1.8.6), which is part of the NIF Target Experimental System (WBS 1.8). This document responds directly to the requirements detailed in NIF Target Experimental System SDR 003 document. Key elements of the Target Area Auxiliary Subsystems include: WBS 1.8.6.1 Local Utility Services; WBS 1.8.6.2 Cable Trays; WBS 1.8.6.3 Personnel, Safety, and Occupational Access; WBS 1.8.6.4 Assembly, Installation, and Maintenance Equipment; WBS 1.8.6.4.1 Target Chamber Service System; WBS 1.8.6.4.2 Target Bay Service Systems

  13. The JPL telerobotic Manipulator Control and Mechanization (MCM) subsystem

    Science.gov (United States)

    Hayati, Samad; Lee, Thomas S.; Tso, Kam; Backes, Paul; Kan, Edwin; Lloyd, J.

    1989-01-01

    The Manipulator Control and Mechanization (MCM) subsystem of the telerobot system provides the real-time control of the robot manipulators in autonomous and teleoperated modes and real time input/output for a variety of sensors and actuators. Substantial hardware and software are included in this subsystem which interfaces in the hierarchy of the telerobot system with the other subsystems. The other subsystems are: run time control, task planning and reasoning, sensing and perception, and operator control subsystem. The architecture of the MCM subsystem, its capabilities, and details of various hardware and software elements are described. Important improvements in the MCM subsystem over the first version are: dual arm coordinated trajectory generation and control, addition of integrated teleoperation, shared control capability, replacement of the ultimate controllers with motor controllers, and substantial increase in real time processing capability.

  14. 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

  15. 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.

  16. Power Subsystem Approach for the Europa Mission

    Directory of Open Access Journals (Sweden)

    Ulloa-Severino Antonio

    2017-01-01

    Full Text Available NASA is planning to launch a spacecraft on a mission to the Jovian moon Europa, in order to conduct a detailed reconnaissance and investigation of its habitability. The spacecraft would orbit Jupiter and perform a detailed science investigation of Europa, utilizing a number of science instruments including an ice-penetrating radar to determine the icy shell thickness and presence of subsurface oceans. The spacecraft would be exposed to harsh radiation and extreme temperature environments. To meet mission objectives, the spacecraft power subsystem is being architected and designed to operate efficiently, and with a high degree of reliability.

  17. Building the IOOS data management subsystem

    Science.gov (United States)

    de La Beaujardière, J.; Mendelssohn, R.; Ortiz, C.; Signell, R.

    2010-01-01

    We discuss progress to date and plans for the Integrated Ocean Observing System (IOOS??) Data Management and Communications (DMAC) subsystem. We begin by presenting a conceptual architecture of IOOS DMAC. We describe work done as part of a 3-year pilot project known as the Data Integration Framework and the subsequent assessment of lessons learned. We present work that has been accomplished as part of the initial version of the IOOS Data Catalog. Finally, we discuss near-term plans for augmenting IOOS DMAC capabilities.

  18. Structure of the Galaxy and its subsystems

    International Nuclear Information System (INIS)

    Ruprecht, J.

    1979-01-01

    Current knowledge is summed up of the structure of our galaxy consisting of more than 100 thousand million stars of an overal mass of 10 44 g, and of interstellar dust and gas. The galaxy comprises several subsystems, the oldest of which being of a spherical shape while the younger ones are more-or-less oblate rotational ellipsoids. It is considered on the basis of visual and radio observations that the galaxy has a spiral structure with many arms, similar to other galaxies. The structure of the galaxy nucleus has not yet been fully explained. (Ha)

  19. Optical fiber telecommunications components and subsystems

    CERN Document Server

    Kaminow, Ivan; Willner, Alan E

    2013-01-01

    Optical Fiber Telecommunications VI (A&B) is the sixth in a series that has chronicled the progress in the R&D of lightwave communications since the early 1970s. Written by active authorities from academia and industry, this edition brings a fresh look to many essential topics, including devices, subsystems, systems and networks. A central theme is the enabling of high-bandwidth communications in a cost-effective manner for the development of customer applications. These volumes are an ideal reference for R&D engineers and managers, optical systems implementers, university researchers and s

  20. Thermal Management Tools for Propulsion System Trade Studies and Analysis

    Science.gov (United States)

    McCarthy, Kevin; Hodge, Ernie

    2011-01-01

    Energy-related subsystems in modern aircraft are more tightly coupled with less design margin. These subsystems include thermal management subsystems, vehicle electric power generation and distribution, aircraft engines, and flight control. Tighter coupling, lower design margins, and higher system complexity all make preliminary trade studies difficult. A suite of thermal management analysis tools has been developed to facilitate trade studies during preliminary design of air-vehicle propulsion systems. Simulink blocksets (from MathWorks) for developing quasi-steady-state and transient system models of aircraft thermal management systems and related energy systems have been developed. These blocksets extend the Simulink modeling environment in the thermal sciences and aircraft systems disciplines. The blocksets include blocks for modeling aircraft system heat loads, heat exchangers, pumps, reservoirs, fuel tanks, and other components at varying levels of model fidelity. The blocksets have been applied in a first-principles, physics-based modeling and simulation architecture for rapid prototyping of aircraft thermal management and related systems. They have been applied in representative modern aircraft thermal management system studies. The modeling and simulation architecture has also been used to conduct trade studies in a vehicle level model that incorporates coupling effects among the aircraft mission, engine cycle, fuel, and multi-phase heat-transfer materials.

  1. Exotic power and propulsion concepts

    International Nuclear Information System (INIS)

    Forward, R.L.

    1990-01-01

    The status of some exotic physical phenomena and unconventional spacecraft concepts that might produce breakthroughs in power and propulsion in the 21st Century are reviewed. The subjects covered include: electric, nuclear fission, nuclear fusion, antimatter, high energy density materials, metallic hydrogen, laser thermal, solar thermal, solar sail, magnetic sail, and tether propulsion

  2. 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...

  3. 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...

  4. Systems Analysis Developed for All-Electric Aircraft Propulsion

    Science.gov (United States)

    Kohout, Lisa L.

    2004-01-01

    There is a growing interest in the use of fuel cells as a power source for all-electric aircraft propulsion as a means to substantially reduce or eliminate environmentally harmful emissions. Among the technologies under consideration for these concepts are advanced proton exchange membrane (PEM) and solid oxide fuel cells (SOFCs), alternative fuels and fuel processing, and fuel storage. A multidisciplinary effort is underway at the NASA Glenn Research Center to develop and evaluate concepts for revolutionary, nontraditional fuel cell power and propulsion systems for aircraft applications. As part of this effort, system studies are being conducted to identify concepts with high payoff potential and associated technology areas for further development. To support this effort, a suite of component models was developed to estimate the mass, volume, and performance for a given system architecture. These models include a hydrogen-air PEM fuel cell; an SOFC; balance-of-plant components (compressor, humidifier, separator, and heat exchangers); compressed gas, cryogenic, and liquid fuel storage tanks; and gas turbine/generator models for hybrid system applications. First-order feasibility studies were completed for an all-electric personal air vehicle utilizing a fuel-cell-powered propulsion system. A representative aircraft with an internal combustion engine was chosen as a baseline to provide key parameters to the study, including engine power and subsystem mass, fuel storage volume and mass, and aircraft range. The engine, fuel tank, and associated ancillaries were then replaced with a fuel cell subsystem. Various configurations were considered including a PEM fuel cell with liquid hydrogen storage, a direct methanol PEM fuel cell, and a direct internal reforming SOFC/turbine hybrid system using liquid methane fuel. Each configuration was compared with the baseline case on a mass and range basis.

  5. Nuclear-microwave-electric propulsion

    International Nuclear Information System (INIS)

    Nordley, G.D.; Brown, W.C.

    1986-01-01

    Electric propulsion can move more mass through space than chemical propulsion by virtue of the higher exhaust velocities achieved by electric propulsion devices. This performance is achieved at the expense of very heavy power sources or very long trip times, which in turn create technical and economic penalties of varying severity. These penalties include: higher operations costs, delayed availability of the payload, and increased exposure to Van Allen Belt radiation. It is proposed to reduce these penalties by physically separating the power source from the propulsion and use microwave energy beaming technology, recently explored and partially developed/tested for Solar Power Satellite concept studies, as an extension cord. This paper summarizes the state of the art of the technology needed for space based beam microwave power cost/performance trades involved with the use beamed microwave/electric propulsion for some typical orbit transfer missions and offers some suggestions for additional work

  6. The Sentinel 4 focal plane subsystem

    Science.gov (United States)

    Hohn, Rüdiger; Skegg, Michael P.; Hermsen, Markus; Hinger, Jürgen; Williges, Christian; Reulke, Ralf

    2017-09-01

    The Sentinel 4 instrument is an imaging spectrometer, developed by Airbus under ESA contract in the frame of the joint European Union (EU)/ESA COPERNICUS program with the objective of monitoring trace gas concentrations. Sentinel 4 will provide accurate measurements of key atmospheric constituents such as ozone, nitrogen dioxide, sulfur dioxide, formaldehyde, as well as aerosol and cloud properties. Sentinel 4 is unique in being the first geostationary UVN mission. The SENTINEL 4 space segment will be integrated on EUMETSAT's Meteosat Third Generation Sounder satellite (MTG-S). Sentinel 4 will provide coverage of Europe and adjacent regions. The Sentinel 4 instrument comprises as a major element two Focal Plane Subsystems (FPS) covering the wavelength ranges 305 nm to 500 nm (UVVIS) and 750 nm to 775 nm (NIR) respectively. The paper describes the Focal Plane Subsystems, comprising the detectors, the optical bench and the control electronics. Further the design and development approach will be presented as well as first measurement results of FPS Qualification Model.

  7. UGV: security analysis of subsystem control network

    Science.gov (United States)

    Abbott-McCune, Sam; Kobezak, Philip; Tront, Joseph; Marchany, Randy; Wicks, Al

    2013-05-01

    Unmanned Ground vehicles (UGVs) are becoming prolific in the heterogeneous superset of robotic platforms. The sensors which provide odometry, localization, perception, and vehicle diagnostics are fused to give the robotic platform a sense of the environment it is traversing. The automotive industry CAN bus has dominated the industry due to the fault tolerance and the message structure allowing high priority messages to reach the desired node in a real time environment. UGVs are being researched and produced at an accelerated rate to preform arduous, repetitive, and dangerous missions that are associated with a military action in a protracted conflict. The technology and applications of the research will inevitably be turned into dual-use platforms to aid civil agencies in the performance of their various operations. Our motivation is security of the holistic system; however as subsystems are outsourced in the design, the overall security of the system may be diminished. We will focus on the CAN bus topology and the vulnerabilities introduced in UGVs and recognizable security vulnerabilities that are inherent in the communications architecture. We will show how data can be extracted from an add-on CAN bus that can be customized to monitor subsystems. The information can be altered or spoofed to force the vehicle to exhibit unwanted actions or render the UGV unusable for the designed mission. The military relies heavily on technology to maintain information dominance, and the security of the information introduced onto the network by UGVs must be safeguarded from vulnerabilities that can be exploited.

  8. RS-34 (Peacekeeper Post Boost Propulsion System) Orbital Debris Application Concept Study

    Science.gov (United States)

    Esther, Elizabeth A.; Burnside, Christopher G.

    2013-01-01

    The Advanced Concepts Office (ACO) at the NASA Marshall Space Flight Center (MSFC) lead a study to evaluate the Rocketdyne produced RS-34 propulsion system as it applies to an orbital debris removal design reference mission. The existing RS-34 propulsion system is a remaining asset from the de-commissioned United States Air Force Peacekeeper ICBM program; specifically the pressure-fed storable bi-propellant Stage IV Post Boost Propulsion System. MSFC gained experience with the RS-34 propulsion system on the successful Ares I-X flight test program flown in the Ares I-X Roll control system (RoCS). The heritage hardware proved extremely robust and reliable and sparked interest for further utilization on other potential in-space applications. Subsequently, MSFC is working closely with the USAF to obtain all the remaining RS-34 stages for re-use opportunities. Prior to pursuit of securing the hardware, MSFC commissioned the Advanced Concepts Office to understand the capability and potential applications for the RS-34 Phoenix stage as it benefits NASA, DoD, and commercial industry. Originally designed, the RS-34 Phoenix provided in-space six-degrees-of freedom operational maneuvering to deploy multiple payloads at various orbital locations. The RS-34 Concept Study, preceded by a utilization study to understand how the unique capabilities of the RS-34 Phoenix and its application to six candidate missions, sought to further understand application for an orbital debris design reference mission as the orbital debris removal mission was found to closely mimic the heritage RS-34 mission. The RS-34 Orbital Debris Application Concept Study sought to identify multiple configurations varying the degree of modification to trade for dry mass optimization and propellant load for overall capability and evaluation of several candidate missions. The results of the RS-34 Phoenix Utilization Study show that the system is technically sufficient to successfully support all of the missions

  9. 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

  10. Fiber-optic sensor demonstrator (FSD) for the monitoring of spacecraft subsystems on ESA's PROBA-2

    Science.gov (United States)

    Kruzelecky, Roman V.; Zou, Jing; Mohammed, Najeeb; Haddad, Emile; Jamroz, Wes; Ricci, Francesco; Lamorie, Joshua; Edwards, Eric; McKenzie, Iain; Vuilleumier, Pierrik

    2017-11-01

    MPB Communications (MPBC) is developing solutions to the monitoring requirements of spacecraft based on its fiber-laser and Fiber Bragg Grating expertise. This is cumulating in the Fiber Sensor Demonstrator for ESA's Proba-2 that is scheduled for launch in 2007. The advantages of the MPBC approach include a central interrogation system that can be used to control a variety of different fiber-optic sensors including temperature, pressure, actuator status, and propellant leakage. This paper reviews the design and ground qualification of the FSD system in preparation for integration with Proba-2. The FSD will provide monitoring for various Proba-2 subsystems, including a hybrid propulsion system. Some of the challenges associated with using fiber-optics in space are discussed.

  11. Double Shell Tank (DST) Process Waste Sampling Subsystem Definition Report

    International Nuclear Information System (INIS)

    RASMUSSEN, J.H.

    2000-01-01

    This report defines the Double-Shell Tank (DST) Process Waste Sampling Subsystem (PWSS). This subsystem definition report fully describes and identifies the system boundaries of the PWSS. This definition provides a basis for developing functional, performance, and test requirements (i.e., subsystem specification), as necessary, for the PWSS. The resultant PWSS specification will include the sampling requirements to support the transfer of waste from the DSTs to the Privatization Contractor during Phase 1 of Waste Feed Delivery

  12. Conditional density matrix: systems and subsystems in quantum mechanics

    International Nuclear Information System (INIS)

    Belokurov, V.V.; Khrustalev, O.A.; Sadovnichij, V.A.; Timofeevskaya, O.D.

    2003-01-01

    A new quantum mechanical notion - Conditional Density Matrix - is discussed and is applied to describe some physical processes. This notion is a natural generalization of von Neumann density matrix for such processes as divisions of quantum systems into subsystems and reunifications of subsystems into new joint systems. Conditional Density Matrix assigns a quantum state to a subsystem of a composite system on condition that another part of the composite system is in some pure state

  13. IOOS modeling subsystem: vision and implementation strategy

    Science.gov (United States)

    Rosenfeld, Leslie; Chao, Yi; Signell, Richard P.

    2012-01-01

    Numerical modeling is vital to achieving the U.S. IOOS® goals of predicting, understanding and adapting to change in the ocean and Great Lakes. In the next decade IOOS should cultivate a holistic approach to coastal ocean prediction, and encourage more balanced investment among the observing, modeling and information management subsystems. We believe the vision of a prediction framework driven by observations, and leveraging advanced technology and understanding of the ocean and Great Lakes, would lead to a new era for IOOS that would not only produce more powerful information, but would also capture broad community support, particularly from the general public, thus allowing IOOS to develop into the comprehensive information system that was envisioned at the outset.

  14. Enabling Electric Propulsion for Flight

    Science.gov (United States)

    Ginn, Starr Renee

    2015-01-01

    Team Seedling project AFRC and LaRC 31ft distributed electric propulsion wing on truck bed up 75 miles per hour for coefficient of lift validation. Convergent Aeronautic Solutions project, sub-project Convergent Electric Propulsion Technologies AFRC, LaRC and GRC, re-winging a 4 passenger Tecnam aircraft with a 31ft distributed electric propulsion wing. Advanced Air Transport Technologies (Fixed Wing), Hybrid Electric Research Theme, developing a series hybrid ironbird and flight sim to study integration and performance challenges in preparation for a 1-2 MW flight project.

  15. 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).

  16. Response spectrum analysis for multi-supported subsystems

    International Nuclear Information System (INIS)

    Reed, J.W.

    1983-01-01

    A methodology was developed to analyze multi-supported subsystems (e.g., piping systems) for seismic or other dynamic forces using response spectrum input. Currently, subsystems which are supported at more than one location in a nuclear power plant building are analyzed either by the time-history method or by response spectrum procedures, where spectra which envelop all support locations are used. The former procedure is exceedingly expensive, while the latter procedure is inexpensive but very conservative. Improved analysis procedures are currently being developed which are either coupled- or uncoupled-system approaches. For the coupled-system approach, response feedback between the subsystem and building system is included. For the uncoupled-system approach, feedback is neglected; however, either time history or response spectrum methods can be used. The methodology developed for analyzing multi-supported subsystems is based on the assumption that the building response and the subsystem response are uncoupled. This is the same assumption implicitly made by analysts who design singly-supported subsystems using floor response spectrum input. This approach implies that there is no response feedback between the primary building system and the subsystem, which is generally found to be conservative. The methodology developed for multi-supported subsystems makes this same assumption and thus should produce results with the same ease and degree of accuracy as results obtained for singly-supported subsystems. (orig./HP)

  17. Automatic control of a primary electric thrust subsystem

    Science.gov (United States)

    Macie, T. W.; Macmedan, M. L.

    1975-01-01

    A concept for automatic control of the thrust subsystem has been developed by JPL and participating NASA Centers. This paper reports on progress in implementing the concept at JPL. Control of the Thrust Subsystem (TSS) is performed by the spacecraft computer command subsystem, and telemetry data is extracted by the spacecraft flight data subsystem. The Data and Control Interface Unit, an element of the TSS, provides the interface with the individual elements of the TSS. The control philosophy and implementation guidelines are presented. Control requirements are listed, and the control mechanism, including the serial digital data intercommunication system, is outlined. The paper summarizes progress to Fall 1974.

  18. Plant development, auxin, and the subsystem incompleteness theorem.

    Science.gov (United States)

    Niklas, Karl J; Kutschera, Ulrich

    2012-01-01

    Plant morphogenesis (the process whereby form develops) requires signal cross-talking among all levels of organization to coordinate the operation of metabolic and genomic subsystems operating in a larger network of subsystems. Each subsystem can be rendered as a logic circuit supervising the operation of one or more signal-activated system. This approach simplifies complex morphogenetic phenomena and allows for their aggregation into diagrams of progressively larger networks. This technique is illustrated here by rendering two logic circuits and signal-activated subsystems, one for auxin (IAA) polar/lateral intercellular transport and another for IAA-mediated cell wall loosening. For each of these phenomena, a circuit/subsystem diagram highlights missing components (either in the logic circuit or in the subsystem it supervises) that must be identified experimentally if each of these basic plant phenomena is to be fully understood. We also illustrate the "subsystem incompleteness theorem," which states that no subsystem is operationally self-sufficient. Indeed, a whole-organism perspective is required to understand even the most simple morphogenetic process, because, when isolated, every biological signal-activated subsystem is morphogenetically ineffective.

  19. 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...

  20. 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...

  1. Lunar Robotic Precursor Missions Using Electric Propulsion

    OpenAIRE

    Winski, Richard G.

    2006-01-01

    A trade study is carried out for the design of electric propulsion based lunar robotic precursor missions. The focus is to understand the relationships between payload mass delivered, electric propulsion power, and trip time. The results are compared against a baseline system using chemical propulsion with LOX/H2. The major differences between the chemical propulsion based and electric propulsion based systems are presented in terms of the payload mass and trip time. It is shown that solar e...

  2. Electric Motors for Vehicle Propulsion

    OpenAIRE

    Larsson, Martin

    2014-01-01

    This work is intended to contribute with knowledge to the area of electic motorsfor propulsion in the vehicle industry. This is done by first studying the differentelectric motors available, the motors suitable for vehicle propulsion are then dividedinto four different types to be studied separately. These four types are thedirect current, induction, permanent magnet and switched reluctance motors. Thedesign and construction are then studied to understand how the different typesdiffer from ea...

  3. Improved Rhenium Thrust Chambers for In-Space Propulsion, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Radiation-cooled, bipropellant thrust chambers are being considered for the ascent/descent engines and reaction control systems for NASA missions such as Mars Sample...

  4. Double Shell Tank (DST) Monitor and Control Subsystem Definition Report

    International Nuclear Information System (INIS)

    BAFUS, R.R.

    2000-01-01

    The system description of the Double-Shell Tank (DST) Monitor and Control Subsystem establishes the system boundaries and describes the interface of the DST Monitor and Control Subsystem with new and existing systems that are required to accomplish the Waste Feed Delivery (WFD) mission

  5. Subsystem cost data for the tritium systems test assembly

    International Nuclear Information System (INIS)

    Bartlit, J.R.; Anderson, J.L.; Rexroth, V.G.

    1983-01-01

    Details of subsystem costs are among the questions most frequently asked about the $14.4 million Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory. This paper presents a breakdown of cost components for each of the 20 major subsystems of TSTA. Also included are details to aid in adjusting the costs to other years, contracting conditions, or system sizes

  6. Does Normal Processing Provide Evidence of Specialised Semantic Subsystems?

    Science.gov (United States)

    Shapiro, Laura R.; Olson, Andrew C.

    2005-01-01

    Category-specific disorders are frequently explained by suggesting that living and non-living things are processed in separate subsystems (e.g. Caramazza & Shelton, 1998). If subsystems exist, there should be benefits for normal processing, beyond the influence of structural similarity. However, no previous study has separated the relative…

  7. Simulating the Various Subsystems of a Coal Mine

    Directory of Open Access Journals (Sweden)

    V. Okolnishnikov

    2016-06-01

    Full Text Available A set of simulation models of various subsystems of a coal mine was developed with the help of a new visual interactive simulation system of technological processes. This paper contains a brief description of this simulation system and its possibilities. The main possibilities provided by the simulation system are: the quick construction of models from library elements, 3D representation, and the communication of models with actual control systems. These simulation models were developed for the simulation of various subsystems of a coal mine: underground conveyor network subsystems, pumping subsystems and coal face subsystems. These simulation models were developed with the goal to be used as a quality and reliability assurance tool for new process control systems in coal mining.

  8. A revolutionary lunar space transportation system architecture using extraterrestrial LOX-augmented NTR propulsion

    Science.gov (United States)

    Borowski, Stanley K.; Corban, Robert R.; Culver, Donald W.; Bulman, Melvin J.; McIlwain, Mel C.

    1994-08-01

    The concept of a liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) engine is introduced, and its potential for revolutionizing lunar space transportation system (LTS) performance using extraterrestrial 'lunar-derived' liquid oxygen (LUNOX) is outlined. The LOX-augmented NTR (LANTR) represents the marriage of conventional liquid hydrogen (LH2)-cooled NTR and airbreathing engine technologies. The large divergent section of the NTR nozzle functions as an 'afterburner' into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging from the NTR's choked sonic throat: 'scramjet propulsion in reverse.' By varying the oxygen-to-fuel mixture ratio (MR), the LANTR concept can provide variable thrust and specific impulse (Isp) capability with a LH2-cooled NTR operating at relatively constant power output. For example, at a MR = 3, the thrust per engine can be increased by a factor of 2.75 while the Isp decreases by only 30 percent. With this thrust augmentation option, smaller, 'easier to develop' NTR's become more acceptable from a mission performance standpoint (e.g., earth escape gravity losses are reduced and perigee propulsion requirements are eliminated). Hydrogen mass and volume is also reduced resulting in smaller space vehicles. An evolutionary NTR-based lunar architecture requiring only Shuttle C and/or 'in-line' shuttle-derived launch vehicles (SDV's) would operate initially in an 'expandable mode' with NTR lunar transfer vehicles (LTV's) delivering 80 percent more payload on piloted missions than their LOX/LH2 chemical propulsion counterparts. With the establishment of LUNOX production facilities on the lunar surface and 'fuel/oxidizer' depot in low lunar orbit (LLO), monopropellant NTR's would be outfitted with an oxygen propellant module, feed system, and afterburner nozzle for 'bipropellant' operation. The LANTR cislunar LTV now transitions to a reusable mode with smaller vehicle and payload doubling benefits on

  9. Presence in the IP Multimedia Subsystem

    Directory of Open Access Journals (Sweden)

    Ling Lin

    2007-01-01

    Full Text Available With an ever increasing penetration of Internet Protocol (IP technologies, the wireless industry is evolving the mobile core network towards all-IP network. The IP Multimedia Subsystem (IMS is a standardised Next Generation Network (NGN architectural framework defined by the 3rd Generation Partnership Project (3GPP to bridge the gap between circuit-switched and packet-switched networks and consolidate both sides into on single all-IP network for all services. In this paper, we provide an insight into the limitation of the presence service, one of the fundamental building blocks of the IMS. Our prototype-based study is unique of its kind and helps identifying the factors which limit the scalability of the current version of the presence service (3GPP TS 23.141 version 7.2.0 Release 7 [1], which will in turn dramatically limit the performance of advanced IMS services. We argue that the client-server paradigm behind the current IMS architecture does not suite the requirements of the IMS system, which defies the very purpose of its introduction. We finally elaborate on possible avenues for addressing this problem.

  10. The CALIPSO Integrated Thermal Control Subsystem

    Science.gov (United States)

    Gasbarre, Joseph F.; Ousley, Wes; Valentini, Marc; Thomas, Jason; Dejoie, Joel

    2007-01-01

    The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) is a joint NASA-CNES mission to study the Earth's cloud and aerosol layers. The satellite is composed of a primary payload (built by Ball Aerospace) and a spacecraft platform bus (PROTEUS, built by Alcatel Alenia Space). The thermal control subsystem (TCS) for the CALIPSO satellite is a passive design utilizing radiators, multi-layer insulation (MLI) blankets, and both operational and survival surface heaters. The most temperature sensitive component within the satellite is the laser system. During thermal vacuum testing of the integrated satellite, the laser system's operational heaters were found to be inadequate in maintaining the lasers required set point. In response, a solution utilizing the laser system's survival heaters to augment the operational heaters was developed with collaboration between NASA, CNES, Ball Aerospace, and Alcatel-Alenia. The CALIPSO satellite launched from Vandenberg Air Force Base in California on April 26th, 2006. Evaluation of both the platform and payload thermal control systems show they are performing as expected and maintaining the critical elements of the satellite within acceptable limits.

  11. 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.

  12. Rosary as the ethnoreligious marker of the actional subsystem of significative field of catholicism

    Directory of Open Access Journals (Sweden)

    V. I. Kryachko

    2015-02-01

    The socioevaluative, autointentional, identificative attempts to explicate some ethnoreligious crosscorrelations between different significative structural fields in sociospace are based on the author’s Model of the structure of significative field of Catholicism, which consists of the following 12 basic significative structural subsystems: 1 anthropomorphic significative subsystem, which includes human­similar (manlike and personificated symbolic constructions, monuments and architectural ensembles, as well as symbols of human body parts, their combinations and signals; 2 zoomorphic significative subsystem, which includes animal­similar significative constructions and signs of their separate bodyparts, as well as symbols of their lifeproducts; 3 vegetomorphic significative subsystem, which includes plant­similar significative elements and food products; 4 geomorphic significative subsystem; 5 geometric significative subsystem; 6 astral­referent significative subsystem; 7 coloristic significative subsystem; 8 topos­instalative significative subsystem; 9 objective­instrumental significative subsystem; 10 architectural exterior­interior significative subsystem; 11 abstractive significative subsystem; 12 actional significative subsystem.

  13. Modeling and simulation of a 100 kWe HT-PEMFC subsystem integrated with an absorption chiller subsystem

    DEFF Research Database (Denmark)

    Arsalis, Alexandros

    2012-01-01

    A 100 kWe liquid-cooled HT-PEMFC subsystem is integrated with an absorption chiller subsystem to provide electricity and cooling. The system is designed, modeled and simulated to investigate the potential of this technology for future novel energy system applications. Liquid-cooling can provide...

  14. Propulsion Health Management System Development for Affordable and Reliable Operation of Space Exploration Systems

    Science.gov (United States)

    Melcher, Kevin J.; Maul, William A.; Garg, Sanjay

    2007-01-01

    The constraints of future Exploration Missions will require unique integrated system health management capabilities throughout the mission. An ambitious launch schedule, human-rating requirements, long quiescent periods, limited human access for repair or replacement, and long communication delays, all require an integrated approach to health management that can span distinct, yet interdependent vehicle subsystems, anticipate failure states, provide autonomous remediation and support the Exploration Mission from beginning to end. Propulsion is a critical part of any space exploration mission, and monitoring the health of the propulsion system is an integral part of assuring mission safety and success. Health management is a somewhat ubiquitous technology that encompasses a large spectrum of physical components and logical processes. For this reason, it is essential to develop a systematic plan for propulsion health management system development. This paper provides a high-level perspective of propulsion health management systems, and describes a logical approach for the future planning and early development that are crucial to planned space exploration programs. It also presents an overall approach, or roadmap, for propulsion health management system development and a discussion of the associated roadblocks and challenges.

  15. Analysis and experimental validation of an HTS linear synchronous propulsion prototype with HTS magnetic suspension

    International Nuclear Information System (INIS)

    Jin Jianxun; Zheng Luhai; Guo Youguang; Xu Wei; Zhu Jianguo

    2011-01-01

    An HTS linear synchronous propulsion prototype with an HTSLSM drive is developed. The feasibility of combining an HTSLSM with an HTS magnetic suspension system has been verified. Three different PMGs are studied by ECS method and experiment verification to obtain an optimal one. The prototype has been tested to obtain the performance and thrust characteristics of the HTSLSM. The measurement results benefit the optimal design and control scheme development for an HTSLSM. A high temperature superconducting (HTS) linear propulsion system composed of a single-sided HTS linear synchronous motor (HTSLSM) in its middle and HTS magnetic suspension sub-systems on both sides has been developed. The HTSLSM uses an HTS bulk magnet array on the moving secondary, and the field-trapped characteristics of the HTS bulk using different magnetized methods have been measured and compared to identify their magnetization capability. In order to generate a large levitation force for the system, three different types of permanent magnet guideways (PMGs) have been numerically analyzed and experimentally verified to obtain an optimal PMG. Based on comprehensive experimental prototype tests, the results show that the HTS linear propulsion system can run with stable magnetic suspension having a constant air-gap length, and the thrust characteristics versus the exciting current, working frequency and the air-gap length have also been obtained. This work forms the basis for developing a practical HTS linear propulsion system by using HTS bulks both for propulsion and suspension.

  16. Nuclear modules for space electric propulsion

    International Nuclear Information System (INIS)

    Difilippo, F.C.

    1998-01-01

    The analysis of interplanetary cargo and piloted missions requires the 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 in an iterative way by using simulations that run fast on a computer. As a consequence of a collaborative agreement between the National Aeronautic and Space Administration (NASA) and the Oak Ridge National Laboratory (ORNL), 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

  17. 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

  18. Nuclear space power and propulsion requirements and issues

    International Nuclear Information System (INIS)

    Swerdling, M.; Isenberg, L.

    1995-01-01

    The use of nuclear power in space is going through a low point. The kinds of missions that would use nuclear power are expensive and there are few new expensive missions. Both NASA and DoD are in a mode of cheaper, faster, better, which means using what is available as much as possible and only incorporating new technology to reduce mission cost. NASA is performing Mission to Planet Earth and detailed exploration missions of Mars. These NASA missions can be done with solar-battery power subsystems and there is no need for nuclear power. The NASA mission to Pluto does require nuclear radioisotope power. Ways to reduce the power subsystem cost and the power level are being investigated. NASA is studying ways to explore beyond Mars with solar-battery power because of the cost and uncertainty in the availability and launchability of nuclear space power systems. The DoD missions are all in earth orbit and can be done with solar-battery systems. The major DoD requirement at present is to reduce costs of all their space missions. One way to do this is to develop highly efficient upper stage boosters that can be integrated with lower cost Earth to low orbit stages and still place their payloads in to higher orbits. One attractive upper stage is a nuclear bimodal (propulsion and power) engine to accomplished lower booster cost to place space assets in GEO. However this is not being pursued because of DOE's new policy not to fund nuclear space power research and development as well as the difficulty in obtaining launch approval for nuclear propulsion and power systems

  19. Subsystem response analysis for the Seismic Safety Margins Research Program

    International Nuclear Information System (INIS)

    Chuang, T.Y.

    1981-01-01

    A review of the state-of-the-art of seismic qualification methods of subsystem has been completed. This task assesses the accuracy of seismic analysis techniques to predict dynamic response, and also identifies and quantifies sources of random and modeling undertainty in subsystem response determination. The subsystem has been classified as two categories according to the nature of support: multiply supported subsystems (e.g., piping systems) and singly supported subsystems (e.g., pumps, turbines, electrical control panels, etc.). The mutliply supported piping systems are analyzed by multisupport input time history method. The input motions are the responses of major structures. The dynamic models of the subsystems identified by the event/fault tree are created. The responses calculated by multisupport input time history method are consistent with the fragility parameters. These responses are also coordinated with the event/fault tree description. The subsystem responses are then evaluated against the fragility curves of components and systems and incorporated in the event/fault tree analysis. (orig./HP)

  20. Failure analysis of satellite subsystems to define suitable de-orbit devices

    Science.gov (United States)

    Palla, Chiara; Peroni, Moreno; Kingston, Jennifer

    2016-11-01

    Space missions in Low Earth Orbit (LEO) are severely affected by the build-up of orbital debris. A key practice, to be compliant with IADC (Inter-Agency Space Debris Coordination Committee) mitigation guidelines, is the removal of space systems that interfere with the LEO region not later than 25 years after the End of Mission. It is important to note that the current guidelines are not generally legally binding, even if different Space Agencies are now looking at the compliance for their missions. If the guidelines will change in law, it will be mandatory to have a postmission disposal strategy for all satellites, including micro and smaller classes. A potential increased number of these satellites is confirmed by different projections, in particular in the commercial sector. Micro and smaller spacecraft are, in general, not provided with propulsion capabilities to achieve a controlled re-entry, so they need different de-orbit disposal methods. When considering the utility of different debris mitigation methods, it is useful to understand which spacecraft subsystems are most likely to fail and how this may affect the operation of a de-orbit system. This also helps the consideration of which components are the most relevant or should be redundant depending on the satellite mass class. This work is based on a sample of LEO and MEO satellites launched between January 2000 and December 2014 with mass lower than 1000 kg. Failure analysis of satellite subsystems is performed by means of the Kaplan-Meier survival analysis; the parametric fits are conducted with Weibull distributions. The study is carried out by using the satellite database SpaceTrak™ which provides anomalies, failures, and trends information for spacecraft subsystems and launch vehicles. The database identifies five states for each satellite subsystem: three degraded states, one fully operational state, and one failed state (complete failure). The results obtained can guide the identification of the

  1. Magnetic levitation and MHD propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Tixador, P [CNRS/CRTBT-LEG, 38 - Grenoble (France)

    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 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.).

  2. 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.)

  3. 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

  4. Human exploration and settlement of the Moon using LUNOX-augmented NTR propulsion

    Science.gov (United States)

    Borowski, Stanley K.; Culver, Donald W.; Bulman, Melvin J.

    1995-10-01

    An innovative trimodal nuclear thermal rocket (NTR) concept is described which combines conventional liquid hydrogen (LH2)-cooled NTR, Brayton cycle power generation and supersonic combustion ramjet (scramjet) technologies. Known as the liquid oxygen (LOX) augmented NTR (LANTR), this concept utilizes the large divergent section of the NTR nozzle as an 'afterburner' into which LOX is injected and supersonically combusted with nuclear preheated hydrogen emerging from the LANTR's choked sonic throat--'scramjet propulsion in reverse.' By varying the oxygen-to-hydrogen mixture ratio (MR), the LANTR can operate over a wide range of thrust and specific impulse (Isp) values while the reactor core power level remains relatively constant. As the MR varies from zero to seven, the thrust-to-weight ratio for a 15 thousand pound force (klbf) NTR increases by approximately 440%--from 3 to 13--while the Isp decreases by only approximately 45%--from 940 to 515 seconds. This thrust augmentation feature of the LANTR means that 'big engine' performance can be obtained using smaller more affordable, easier to test NTR engines. 'Reoxidizing' the bipropellant LANTR system in low lunar orbit (LLO) with high density 'lunar-derived' LOX (LUNOX) enables a reusable, reduced size and mass lunar transfer vehicle (LTV) which can be deployed and resupplied using two 66 t-class Shuttle-derived launch vehicles. The reusable LANTR can also transport 200 to 300% more payload on each piloted round trip mission than an expendable 'all LH2' NTR system. As initial outposts grow to eventual lunar settlements and LUNOX production capacity increases, the LANTR concept can also enable a rapid 'commuter' shuttle capable of 36 to 24 hour 'one way' trips to the Moon and back with reasonable size vehicles and initial mass in low Earth orbit (IMLEO) requirements.

  5. Shuttle Orbiter Active Thermal Control Subsystem design and flight experience

    Science.gov (United States)

    Bond, Timothy A.; Metcalf, Jordan L.; Asuncion, Carmelo

    1991-01-01

    The paper examines the design of the Space Shuttle Orbiter Active Thermal Control Subsystem (ATCS) constructed for providing the vehicle and payload cooling during all phases of a mission and during ground turnaround operations. The operation of the Shuttle ATCS and some of the problems encountered during the first 39 flights of the Shuttle program are described, with special attention given to the major problems encountered with the degradation of the Freon flow rate on the Orbiter Columbia, the Flash Evaporator Subsystem mission anomalies which occurred on STS-26 and STS-34, and problems encountered with the Ammonia Boiler Subsystem. The causes and the resolutions of these problems are discussed.

  6. Subsystem response review. Seismic safety margins research program

    International Nuclear Information System (INIS)

    Kennedy, R.P.; Campbell, R.D.; Wesley, D.A.; Kamil, H.; Gantayat, A.; Vasudevan, R.

    1981-07-01

    A study was conducted to document the state of the art in seismic qualification of nuclear power plant components and subsystems by analysis and testing and to identify the sources and magnitude of the uncertainties associated with analysis and testing methods. The uncertainties are defined in probabilistic terms for use in probabilistic seismic risk studies. Recommendations are made for the most appropriate subsystem response analysis methods to minimize response uncertainties. Additional studies, to further quantify testing uncertainties, are identified. Although the general effect of non-linearities on subsystem response is discussed, recommendations and conclusions are based principally on linear elastic analysis and testing models. (author)

  7. Airbreathing engine selection criteria for SSTO propulsion system

    Science.gov (United States)

    Ohkami, Yoshiaki; Maita, Masataka

    1995-02-01

    This paper presents airbreathing engine selection criteria to be applied to the propulsion system of a Single Stage To Orbit (SSTO). To establish the criteria, a relation among three major parameters, i.e., delta-V capability, weight penalty, and effective specific impulse of the engine subsystem, is derived as compared to these parameters of the LH2/LOX rocket engine. The effective specific impulse is a function of the engine I(sub sp) and vehicle thrust-to-drag ratio which is approximated by a function of the vehicle velocity. The weight penalty includes the engine dry weight, cooling subsystem weight. The delta-V capability is defined by the velocity region starting from the minimum operating velocity up to the maximum velocity. The vehicle feasibility is investigated in terms of the structural and propellant weights, which requires an iteration process adjusting the system parameters. The system parameters are computed by iteration based on the Newton-Raphson method. It has been concluded that performance in the higher velocity region is extremely important so that the airbreathing engines are required to operate beyond the velocity equivalent to the rocket engine exhaust velocity (approximately 4500 m/s).

  8. Center for Advanced Space Propulsion Second Annual Technical Symposium Proceedings

    Science.gov (United States)

    1990-01-01

    The proceedings for the Center for Advanced Space Propulsion Second Annual Technical Symposium are divided as follows: Chemical Propulsion, CFD; Space Propulsion; Electric Propulsion; Artificial Intelligence; Low-G Fluid Management; and Rocket Engine Materials.

  9. Propulsion of magnetically levitated trains

    Energy Technology Data Exchange (ETDEWEB)

    Wipf, S L

    1976-05-01

    A propulsion system for magnetically levitated trains is proposed. A method of periodically energizing magnetic loops on a train moving over a periodically undulating track allows the net repulsive magnetic force to tilt forward or backward for either propulsion or braking. The principle is explained and a specific example discussed. Approximate calculations show feasibility. Problems requiring technical solutions which cannot be considered present state-of-the-art are AC losses at frequencies up to 20 Hz and mechanical fatigue properties at low temperatures. Suitable primary power could be derived from hydrogen-fueled turbines yet to be developed.

  10. Aeronautic propulsion systems; Propulseurs aeronautiques

    Energy Technology Data Exchange (ETDEWEB)

    Lepourry, P; Ciryci, R

    1992-12-31

    This book is devoted to airplane pilots having a private licence and who would like to take up a professional rank. It comprises 8 chapters dealing with: the different type of propulsion systems, turbojet, turbofan and piston engines; the propeller (characteristics, different types, functioning, protection systems..); the piston engines (4-stroke cycle, power and efficiency, description, characteristics); the gas generator and its limitations (air intake, combustion chamber, turbines, nozzles, fuel systems..); the performances of propulsion systems; the drive, control and instruments; and the use of engines. The last chapter is a self-evaluation questionnaire about the notions developed in the book. (J.S.)

  11. 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.

  12. In-Space Propulsion Technology Program Solar Electric Propulsion Technologies

    Science.gov (United States)

    Dankanich, John W.

    2006-01-01

    NASA's In-space Propulsion (ISP) Technology Project is developing new propulsion technologies that can enable or enhance near and mid-term NASA science missions. The Solar Electric Propulsion (SEP) technology area has been investing in NASA s Evolutionary Xenon Thruster (NEXT), the High Voltage Hall Accelerator (HiVHAC), lightweight reliable feed systems, wear testing, and thruster modeling. These investments are specifically targeted to increase planetary science payload capability, expand the envelope of planetary science destinations, and significantly reduce the travel times, risk, and cost of NASA planetary science missions. Status and expected capabilities of the SEP technologies are reviewed in this presentation. The SEP technology area supports numerous mission studies and architecture analyses to determine which investments will give the greatest benefit to science missions. Both the NEXT and HiVHAC thrusters have modified their nominal throttle tables to better utilize diminished solar array power on outbound missions. A new life extension mechanism has been implemented on HiVHAC to increase the throughput capability on low-power systems to meet the needs of cost-capped missions. Lower complexity, more reliable feed system components common to all electric propulsion (EP) systems are being developed. ISP has also leveraged commercial investments to further validate new ion and hall thruster technologies and to potentially lower EP mission costs.

  13. 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.

  14. Deployable Propulsion and Power Systems for Solar System Exploration

    Science.gov (United States)

    Johnson, Les; Carr, John

    2017-01-01

    NASA is developing thin-film based, deployable propulsion, power and communication systems for small spacecraft that could provide a revolutionary new capability allowing small spacecraft exploration of the solar system. The Near Earth Asteroid (NEA) Scout reconnaissance mission will demonstrate solar sail propulsion on a 6U CubeSat interplanetary spacecraft and lay the groundwork for their future use in deep space science and exploration missions. Solar sails use sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like sail made of a lightweight, highly reflective material. This continuous photon pressure provides propellantless thrust, allowing for very high delta V maneuvers on long-duration, deep space exploration. Since reflected light produces thrust, solar sails require no onboard propellant. The Lightweight Integrated Solar Array and Transceiver (LISA-T) is a launch stowed, orbit deployed array on which thin-film photovoltaic and antenna elements are embedded. Inherently, small satellites are limited in surface area, volume, and mass allocation; driving competition between power, communications, and GN&C (guidance navigation and control) subsystems. This restricts payload capability and limits the value of these low-cost satellites. LISA-T is addressing this issue, deploying large-area arrays from a reduced volume and mass envelope - greatly enhancing power generation and communications capabilities of small spacecraft. The NEA Scout mission, funded by NASA's Advanced Exploration Systems Program and managed by NASA MSFC, will use the solar sail as its primary propulsion system, allowing it to survey and image one or more NEA's of interest for possible future human exploration. NEA Scout uses a 6U cubesat (to be provided by NASA's Jet Propulsion Laboratory), an 86 sq m solar sail and will weigh less than 12 kilograms. NEA Scout will be launched on the first flight of the Space Launch System in 2018. Similar in concept

  15. ngVLA Cryogenic Subsystem Concept

    Science.gov (United States)

    Wootten, Al; Urbain, Denis; Grammer, Wes; Durand, S.

    2018-01-01

    The VLA’s success over 35 years of operations stems in part from dramatically upgraded components over the years. The time has come to build a new array to lead the radio astronomical science into its next 40 years. To accomplish that, a next generation VLA (ngVLA) is envisioned to have 214 antennas with diameters of 18m. The core of the array will be centered at the current VLA location, but the arms will extend out to 1000km.The VLA cryogenic subsystem equipment and technology have remained virtually unchanged since the early 1980s. While adequate for a 27-antenna array, scaling the current system for an array of 214 antennas would be prohibitively expensive in terms of operating cost and maintenance. The overall goal is to limit operating cost to within three times the current level, despite having 8 times the number of antennas. To help realize this goal, broadband receivers and compact feeds will be utilized to reduce both the size and number of cryostats required. The current baseline front end concept calls for just two moderately-sized cryostats for the entire 1.2-116 GHz frequency range, as opposed to 8 in the VLA.For the ngVLA cryogenics, our objective is a well-optimized and efficient system that uses state-of-the-art technology to minimize per-antenna power consumption and maximize reliability. Application of modern technologies, such as variable-speed operation for the scroll compressors and cryocooler motor drives, allow the cooling capacity of the system to be dynamically matched to thermal loading in each cryostat. Significantly, power savings may be realized while the maintenance interval of the cryocoolers is also extended.Finally, a receiver designed to minimize thermal loading can produce savings directly translating to lower operating cost when variable-speed drives are used. Multi-layer insulation (MLI) on radiation shields and improved IR filters on feed windows can significantly reduce heat loading.Measurements done on existing cryogenic

  16. THE FUTURE OF SPACECRAFT NUCLEAR PROPULSION

    OpenAIRE

    Jansen, Frank

    2014-01-01

    This paper summarizes the advantages of space nuclear power and propulsion systems. It describes the actual status of international power level dependent spacecraft nuclear propulsion missions, especially the high power EU-Russian MEGAHIT study including the Russian Megawatt-Class Nuclear Power Propulsion System, the NASA GRC project and the low and medium power EU DiPoP study. Space nuclear propulsion based mission scenarios of these studies are sketched as well.

  17. Development status of a preprototype water electrolysis subsystem

    Science.gov (United States)

    Martin, R. B.; Erickson, A. C.

    1981-01-01

    A preprototype water electrolysis subsystem was designed and fabricated for NASA's advanced regenerative life support program. A solid polymer is used for the cell electrolyte. The electrolysis module has 12 cells that can generate 5.5 kg/day of oxygen for the metabolic requirements of three crewmembers, for cabin leakage, and for the oxygen and hydrogen required for carbon dioxide collection and reduction processes. The subsystem can be operated at a pressure between 276 and 2760 kN/sq m and in a continuous constant-current, cyclic, or standby mode. A microprocessor is used to aid in operating the subsystem. Sensors and controls provide fault detection and automatic shutdown. The results of development, demonstration, and parametric testing are presented. Modifications to enhance operation in an integrated and manned test are described. Prospective improvements for the electrolysis subsystem are discussed.

  18. PREVAIL-EPL alpha tool electron optics subsystem

    Science.gov (United States)

    Pfeiffer, Hans C.; Dhaliwal, Rajinder S.; Golladay, Steven D.; Doran, Samuel K.; Gordon, Michael S.; Kendall, Rodney A.; Lieberman, Jon E.; Pinckney, David J.; Quickle, Robert J.; Robinson, Christopher F.; Rockrohr, James D.; Stickel, Werner; Tressler, Eileen V.

    2001-08-01

    The IBM/Nikon alliance is continuing pursuit of an EPL stepper alpha tool based on the PREVAIL technology. This paper provides a status report of the alliance activity with particular focus on the Electron Optical Subsystem developed at IBM. We have previously reported on design features of the PREVAIL alpha system. The new state-of-the-art e-beam lithography concepts have since been reduced to practice and turned into functional building blocks of a production level lithography tool. The electron optical alpha tool subsystem has been designed, build, assembled and tested at IBM's Semiconductor Research and Development Center (SRDC) in East Fishkill, New York. After demonstrating subsystem functionality, the electron optical column and all associated control electronics hardware and software have been shipped during January 2001 to Nikon's facility in Kumagaya, Japan, for integration into the Nikon commercial e-beam stepper alpha tool. Early pre-shipment results obtained with this electron optical subsystem are presented.

  19. Automated Subsystem Control for Life Support System (ASCLSS)

    Science.gov (United States)

    Block, Roger F.

    1987-01-01

    The Automated Subsystem Control for Life Support Systems (ASCLSS) program has successfully developed and demonstrated a generic approach to the automation and control of space station subsystems. The automation system features a hierarchical and distributed real-time control architecture which places maximum controls authority at the lowest or process control level which enhances system autonomy. The ASCLSS demonstration system pioneered many automation and control concepts currently being considered in the space station data management system (DMS). Heavy emphasis is placed on controls hardware and software commonality implemented in accepted standards. The approach demonstrates successfully the application of real-time process and accountability with the subsystem or process developer. The ASCLSS system completely automates a space station subsystem (air revitalization group of the ASCLSS) which moves the crew/operator into a role of supervisory control authority. The ASCLSS program developed over 50 lessons learned which will aide future space station developers in the area of automation and controls..

  20. Effector-Triggered Self-Replication in Coupled Subsystems.

    Science.gov (United States)

    Komáromy, Dávid; Tezcan, Meniz; Schaeffer, Gaël; Marić, Ivana; Otto, Sijbren

    2017-11-13

    In living systems processes like genome duplication and cell division are carefully synchronized through subsystem coupling. If we are to create life de novo, similar control over essential processes such as self-replication need to be developed. Here we report that coupling two dynamic combinatorial subsystems, featuring two separate building blocks, enables effector-mediated control over self-replication. The subsystem based on the first building block shows only self-replication, whereas that based on the second one is solely responsive toward a specific external effector molecule. Mixing the subsystems arrests replication until the effector molecule is added, resulting in the formation of a host-effector complex and the liberation of the building block that subsequently engages in self-replication. The onset, rate and extent of self-replication is controlled by the amount of effector present. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  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. 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

  3. Distributed propulsion and future aerospace technologies

    OpenAIRE

    Ameyugo, Gregorio

    2007-01-01

    This thesis describes an Engineering Doctorate project in Distributed Propulsion carried out from 2004 to 2007 at Cranfield University. Distributed propulsion is a propulsion system arrangement that consists in spreading the engine thrust along the aircraft span. This can be accomplished by distributing a series of driven fans or the engines themselves. The aim of this project is to determine the feasibility of ...

  4. Measurement system as a subsystem of the quality management system

    OpenAIRE

    Ľubica Floreková; Ján Terpák; Marcela Čarnogurská

    2006-01-01

    Each measurement system and a control principle must be based on certain facts about the system behaviour (what), operation (how) and structure (why). Each system is distributed into subsystems that provide an input for the next subsystem. For each system, start is important the begin, that means system characteristics, collecting of data, its hierarchy and the processes distribution.A measurement system (based on the chapter 8 of the standard ISO 9001:2000 Quality management system, requirem...

  5. Opto-mechanical subsystem with temperature compensation through isothemal design

    Science.gov (United States)

    Goodwin, F. E. (Inventor)

    1977-01-01

    An opto-mechanical subsystem for supporting a laser structure which minimizes changes in the alignment of the laser optics in response to temperature variations is described. Both optical and mechanical structural components of the system are formed of the same material, preferably beryllium, which is selected for high mechanical strength and good thermal conducting qualities. All mechanical and optical components are mounted and assembled to provide thorough thermal coupling throughout the subsystem to prevent the development of temperature gradients.

  6. Ultrasonic propulsion of kidney stones.

    Science.gov (United States)

    May, Philip C; Bailey, Michael R; Harper, Jonathan D

    2016-05-01

    Ultrasonic propulsion is a novel technique that uses short bursts of focused ultrasonic pulses to reposition stones transcutaneously within the renal collecting system and ureter. The purpose of this review is to discuss the initial testing of effectiveness and safety, directions for refinement of technique and technology, and opinions on clinical application. Preclinical studies with a range of probes, interfaces, and outputs have demonstrated feasibility and consistent safety of ultrasonic propulsion with room for increased outputs and refinement toward specific applications. Ultrasonic propulsion was used painlessly and without adverse events to reposition stones in 14 of 15 human study participants without restrictions on patient size, stone size, or stone location. The initial feasibility study showed applicability in a range of clinically relevant situations, including facilitating passage of residual fragments following ureteroscopy or shock wave lithotripsy, moving a large stone at the ureteropelvic junction with relief of pain, and differentiating large stones from a collection of small fragments. Ultrasonic propulsion shows promise as an office-based system for transcutaneously repositioning kidney stones. Potential applications include facilitating expulsion of residual fragments following ureteroscopy or shock wave lithotripsy, repositioning stones prior to treatment, and repositioning obstructing ureteropelvic junction stones into the kidney to alleviate acute renal colic.

  7. An Algorithm for Integrated Subsystem Embodiment and System Synthesis

    Science.gov (United States)

    Lewis, Kemper

    1997-01-01

    Consider the statement,'A system has two coupled subsystems, one of which dominates the design process. Each subsystem consists of discrete and continuous variables, and is solved using sequential analysis and solution.' To address this type of statement in the design of complex systems, three steps are required, namely, the embodiment of the statement in terms of entities on a computer, the mathematical formulation of subsystem models, and the resulting solution and system synthesis. In complex system decomposition, the subsystems are not isolated, self-supporting entities. Information such as constraints, goals, and design variables may be shared between entities. But many times in engineering problems, full communication and cooperation does not exist, information is incomplete, or one subsystem may dominate the design. Additionally, these engineering problems give rise to mathematical models involving nonlinear functions of both discrete and continuous design variables. In this dissertation an algorithm is developed to handle these types of scenarios for the domain-independent integration of subsystem embodiment, coordination, and system synthesis using constructs from Decision-Based Design, Game Theory, and Multidisciplinary Design Optimization. Implementation of the concept in this dissertation involves testing of the hypotheses using example problems and a motivating case study involving the design of a subsonic passenger aircraft.

  8. An analytical model for an input/output-subsystem

    International Nuclear Information System (INIS)

    Roemgens, J.

    1983-05-01

    An input/output-subsystem of one or several computers if formed by the external memory units and the peripheral units of a computer system. For these subsystems mathematical models are established, taking into account the special properties of the I/O-subsystems, in order to avoid planning errors and to allow for predictions of the capacity of such systems. Here an analytical model is presented for the magnetic discs of a I/O-subsystem, using analytical methods for the individual waiting queues or waiting queue networks. Only I/O-subsystems of IBM-computer configurations are considered, which can be controlled by the MVS operating system. After a description of the hardware and software components of these I/O-systems, possible solutions from the literature are presented and discussed with respect to their applicability in IBM-I/O-subsystems. Based on these models a special scheme is developed which combines the advantages of the literature models and avoids the disadvantages in part. (orig./RW) [de

  9. Independent Orbiter Assessment (IOA): Assessment of the orbiter main propulsion system FMEA/CIL, volume 1

    Science.gov (United States)

    Slaughter, B. C.

    1988-01-01

    The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Main Propulsion System (MPS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to available data from the Rockwell Downey/NASA JSC FMEA/CIL review. The Orbiter MPS is composed of the Propellant Management Subsystem (PMS) consisting of the liquid oxygen (LO2) and liquid hydrogen (LH2) subsystems and the helium subsystem. The PMS is a system of manifolds, distribution lines, and valves by which the liquid propellants pass from the External Tank to the Space Shuttle Main Engine (SSME). The helium subsystem consists of a series of helium supply tanks and their associated regulators, control valves, and distribution lines. Volume 1 contains the MPS description, assessment results, ground rules and assumptions, and some of the IOA worksheets.

  10. Extending the Scope of the Resource Admission Control Subsystem (RACS) in IP multimedia subsystem using cognitive radios

    CSIR Research Space (South Africa)

    Muwonge, BK

    2008-04-01

    Full Text Available is greatly increased, and resource reservation and QoS management by the RACS is also greatly increased. Index Terms—Traffic Engineering; Cross Layer; Cognitive Radio, IP Multimedia Subsystem (IMS) I. INTRODUCTION HE IP Multimedia Subsystem (IMS...) is seen as the answer to the much talked-about convergence of data and telecommunication services. The original IMS design was by the 3rd Generation Partnership Project (3GPP) for delivering IP Multimedia services to end users, using telecommunication...

  11. Software To Secure Distributed Propulsion Simulations

    Science.gov (United States)

    Blaser, Tammy M.

    2003-01-01

    Distributed-object computing systems are presented with many security threats, including network eavesdropping, message tampering, and communications middleware masquerading. NASA Glenn Research Center, and its industry partners, has taken an active role in mitigating the security threats associated with developing and operating their proprietary aerospace propulsion simulations. In particular, they are developing a collaborative Common Object Request Broker Architecture (CORBA) Security (CORBASec) test bed to secure their distributed aerospace propulsion simulations. Glenn has been working with its aerospace propulsion industry partners to deploy the Numerical Propulsion System Simulation (NPSS) object-based technology. NPSS is a program focused on reducing the cost and time in developing aerospace propulsion engines

  12. Concept Design of High Power Solar Electric Propulsion Vehicles for Human Exploration

    Science.gov (United States)

    Hoffman, David J.; Kerslake, Thomas W.; Hojnicki, Jeffrey S.; Manzella, David H.; Falck, Robert D.; Cikanek, Harry A., III; Klem, Mark D.; Free, James M.

    2011-01-01

    Human exploration beyond low Earth orbit will require enabling capabilities that are efficient, affordable and reliable. Solar electric propulsion (SEP) has been proposed by NASA s Human Exploration Framework Team as one option to achieve human exploration missions beyond Earth orbit because of its favorable mass efficiency compared to traditional chemical propulsion systems. This paper describes the unique challenges associated with developing a large-scale high-power (300-kWe class) SEP vehicle and design concepts that have potential to meet those challenges. An assessment of factors at the subsystem level that must be considered in developing an SEP vehicle for future exploration missions is presented. Overall concepts, design tradeoffs and pathways to achieve development readiness are discussed.

  13. Optimization of extended propulsion time nuclear-electric propulsion trajectories

    Science.gov (United States)

    Sauer, C. G., Jr.

    1981-01-01

    This paper presents the methodology used in optimizing extended propulsion time NEP missions considering realistic thruster lifetime constraints. These missions consist of a powered spiral escape from a 700-km circular orbit at the earth, followed by a powered heliocentric transfer with an optimized coast phase, and terminating in a spiral capture phase at the target planet. This analysis is most applicable to those missions with very high energy requirements such as outer planet orbiter missions or sample return missions where the total propulsion time could greatly exceed the expected lifetime of an individual thruster. This methodology has been applied to the investigation of NEP missions to the outer planets where examples are presented of both constrained and optimized trajectories.

  14. Development and Qualification of ATV Propulsion Assemblies

    Science.gov (United States)

    Riehle, M.; Jost, R.

    2002-01-01

    In the frame of the development and operation of the International Space Station ISS, the European Space Agency ESA is not only contributing experiments and a laboratory module but also logistics capacity. This purpose of supplying the ISS shall be covered by an unmanned, Automated Transfer Vehicle (ATV) that will be launched for the first time in 2004 by Ariane 5. The development of the ATV is in close conjunction to the future Ariane 5 launch capacity of about 20 tons injected into low earth orbit. Thus this unmanned transporter will be a quite large space craft that is subjected to fulfil several mission objectives apart of only delivering cargo such as multiple automatic docking/de-docking, re-boost services and re-fuelling. For those reasons and due to its dimensions the propulsion sub-system is one of the most sophisticated in the field of space propulsion. Even safety issues of manned space flight have to be applied since the pressurised cargo section is part of the ISS when docked to the manned modules. This leads to by far the largest but also the most sophisticated propulsion system ever built in Europe. Astrium as one of the major partners of this european project is responsible for this major system that will be described in the paper. Focusing on the major core assemblies such as multi thruster platforms, pressure control system incl. safety and redundancy mechanisms as well as tanks and other components that completes a propulsion system. System Design and Qualification Starting from the basic criteria the paper will present the major performance requirements such as pressures, thrust levels and other parameters that led to the selection of major components of the system such as thrusters, valves, tanks, etc. Some of the component could be selected from off the shelve, whereas other core components such as the 200N Attitude Control and Braking Thrusters or Propellant Tanks had to be newly developed. The stepwise approach of development and careful

  15. 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

  16. Simulation of hybrid vehicle propulsion with an advanced battery model

    Energy Technology Data Exchange (ETDEWEB)

    Nallabolu, S.; Kostetzer, L.; Rudnyi, E. [CADFEM GmbH, Grafing (Germany); Geppert, M.; Quinger, D. [LION Smart GmbH, Frieding (Germany)

    2011-07-01

    In the recent years there has been observed an increasing concern about global warming and greenhouse gas emissions. In addition to the environmental issues the predicted scarcity of oil supplies and the dramatic increase in oil price puts new demands on vehicle design. As a result energy efficiency and reduced emission have become one of main selling point for automobiles. Hybrid electric vehicles (HEV) have therefore become an interesting technology for the governments and automotive industries. HEV are more complicated compared to conventional vehicles due to the fact that these vehicles contain more electrical components such as electric machines, power electronics, electronic continuously variable transmissions (CVT), and embedded powertrain controllers. Advanced energy storage devices and energy converters, such as Li-ion batteries, ultracapacitors, and fuel cells are also considered. A detailed vehicle model used for an energy flow analysis and vehicle performance simulation is necessary. Computer simulation is indispensible to facilitate the examination of the vast hybrid electric vehicle design space with the aim to predict the vehicle performance over driving profiles, estimate fuel consumption and the pollution emissions. There are various types of mathematical models and simulators available to perform system simulation of vehicle propulsion. One of the standard methods to model the complete vehicle powertrain is ''backward quasistatic modeling''. In this method vehicle subsystems are defined based on experiential models in the form of look-up tables and efficiency maps. The interaction between adjacent subsystems of the vehicle is defined through the amount of power flow. Modeling the vehicle subsystems like motor, engine, gearbox and battery is under this technique is based on block diagrams. The vehicle model is applied in two case studies to evaluate the vehicle performance and fuel consumption. In the first case study the affect

  17. Double-Shell Tank (DST) Monitor and Control Subsystem Specification

    International Nuclear Information System (INIS)

    BAFUS, R.R.

    2000-01-01

    This specification establishes the performance requirements and provides references to the requisite codes and standards to be applied during design of the Double-Shell Tank (DST) Monitor and Control Subsystem that supports the first phase of Waste Feed Delivery. This subsystem specification establishes the interface and performance requirements and provides references to the requisite codes and standards to be applied during the design of the Double-Shell Tank (DST) Monitor and Control Subsystem. The DST Monitor and Control Subsystem consists of the new and existing equipment that will be used to provide tank farm operators with integrated local monitoring and control of the DST systems to support Waste Feed Delivery (WFD). New equipment will provide automatic control and safety interlocks where required and provide operators with visibility into the status of DST subsystem operations (e.g., DST mixer pump operation and DST waste transfers) and the ability to manually control specified DST functions as necessary. This specification is intended to be the basis for new project/installations (W-521, etc.). This specification is not intended to retroactively affect previously established project design criteria without specific direction by the program

  18. Preprototype vapor compression distillation subsystem. [recovering potable water from wastewater

    Science.gov (United States)

    Ellis, G. S.; Wynveen, R. A.; Schubert, F. H.

    1979-01-01

    A three-person capacity preprototype vapor compression distillation subsystem for recovering potable water from wastewater aboard spacecraft was designed, assembled, and tested. The major components of the subsystem are: (1) a distillation unit which includes a compressor, centrifuge, central shaft, and outer shell; (2) a purge pump; (3) a liquids pump; (4) a post-treat cartridge; (5) a recycle/filter tank; (6) an evaporator high liquid level sensor; and (7) the product water conductivity monitor. A computer based control monitor instrumentation carries out operating mode change sequences, monitors and displays subsystem parameters, maintains intramode controls, and stores and displays fault detection information. The mechanical hardware occupies 0.467 m3, requires 171 W of electrical power, and has a dry weight of 143 kg. The subsystem recovers potable water at a rate of 1.59 kg/hr, which is equivalent to a duty cycle of approximately 30% for a crew of three. The product water has no foul taste or odor. Continued development of the subsystem is recommended for reclaiming water for human consumption as well as for flash evaporator heat rejection, urinal flushing, washing, and other on-board water requirements.

  19. Planetary explorer liquid propulsion study

    Science.gov (United States)

    Mckevitt, F. X.; Eggers, R. F.; Bolz, C. W.

    1971-01-01

    An analytical evaluation of several candidate monopropellant hydrazine propulsion system approaches is conducted in order to define the most suitable configuration for the combined velocity and attitude control system for the Planetary Explorer spacecraft. Both orbiter and probe-type missions to the planet Venus are considered. The spacecraft concept is that of a Delta launched spin-stabilized vehicle. Velocity control is obtained through preprogrammed pulse-mode firing of the thrusters in synchronism with the spacecraft spin rate. Configuration selection is found to be strongly influenced by the possible error torques induced by uncertainties in thruster operation and installation. The propulsion systems defined are based on maximum use of existing, qualified components. Ground support equipment requirements are defined and system development testing outlined.

  20. Assessing Hypothetical Gravity Control Propulsion

    OpenAIRE

    Millis, Marc G.

    2006-01-01

    Gauging the benefits of hypothetical gravity control propulsion is difficult, but addressable. The major challenge is that such breakthroughs are still only notional concepts rather than being specific methods from which performance can be rigorously quantified. A recent assessment by Tajmar and Bertolami used the rocket equation to correct naive misconceptions, but a more fundamental analysis requires the use of energy as the basis for comparison. The energy of a rocket is compared to an ide...

  1. Turboelectric Distributed Propulsion System Modelling

    OpenAIRE

    Liu, Chengyuan

    2013-01-01

    The Blended-Wing-Body is a conceptual aircraft design with rear-mounted, over wing engines. Turboelectric distributed propulsion system with boundary layer ingestion has been considered for this aircraft. It uses electricity to transmit power from the core turbine to the fans, therefore dramatically increases bypass ratio to reduce fuel consumption and noise. This dissertation presents methods on designing the TeDP system, evaluating effects of boundary layer ingestion, modelling engine perfo...

  2. 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

  3. Propulsion Systems in Water Tunnel

    Directory of Open Access Journals (Sweden)

    Nobuyuki Fujisawa

    1995-01-01

    agreement with the field experiment with prototype craft. Measurements are also made for the losses in the intake and the nozzle. The optimization study of the water jet systems is conducted by simulating the change of the nozzle outlet diameter with the variable nozzle arrangement. It is suggested that the nozzle outlet diameter should be decreased as the craft velocity increases to obtain an optimum propulsive efficiency in a wide range of craft velocity.

  4. The Main Subsystems Involved in Defining the Quality Management System in a Hospital

    Directory of Open Access Journals (Sweden)

    Dobrea Valentina Alina

    2010-06-01

    Full Text Available The hospital is the most important organization in health field, so they have to improve the quality in all the activities deployed. A very suitable way to show the hospital’s preoccupation for quality of health services is the quality management system certificate according ISO 9001/2000. In understanding the architecture of the hospital quality management system is necessary to decompose this system in subsystems and analyze each separately: the managerial subsystem, the human subsystem, the social subsystem, thetechnical subsystem, the informative subsystem. The relationship between those subsystems leads to the continuous improvement of quality in health services.

  5. Space station propulsion requirements study

    Science.gov (United States)

    Wilkinson, C. L.; Brennan, S. M.

    1985-01-01

    Propulsion system requirements to support Low Earth Orbit (LEO) manned space station development and evolution over a wide range of potential capabilities and for a variety of STS servicing and space station operating strategies are described. The term space station and the overall space station configuration refers, for the purpose of this report, to a group of potential LEO spacecraft that support the overall space station mission. The group consisted of the central space station at 28.5 deg or 90 deg inclinations, unmanned free-flying spacecraft that are both tethered and untethered, a short-range servicing vehicle, and a longer range servicing vehicle capable of GEO payload transfer. The time phasing for preferred propulsion technology approaches is also investigated, as well as the high-leverage, state-of-the-art advancements needed, and the qualitative and quantitative benefits of these advancements on STS/space station operations. The time frame of propulsion technologies applicable to this study is the early 1990's to approximately the year 2000.

  6. 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.

  7. Development and Integration of the Janus Robotic Lander: A Liquid Oxygen-Liquid Methane Propulsion System Testbed

    Science.gov (United States)

    Ponce, Raul

    Initiatives have emerged with the goal of sending humans to other places in our solar system. New technologies are being developed that will allow for more efficient space systems to transport future astronauts. One of those technologies is the implementation of propulsion systems that use liquid oxygen and liquid methane (LO2-LCH4) as propellants. The benefits of a LO2-LCH4 propulsion system are plenty. One of the main advantages is the possibility of manufacturing the propellants at the destination body. A space vehicle which relies solely on liquid oxygen and liquid methane for its main propulsion and reaction control engines is necessary to exploit this advantage. At the University of Texas at El Paso (UTEP) MIRO Center for Space Exploration Technology Research (cSETR) such a vehicle is being developed. Janus is a robotic lander vehicle with the capability of vertical take-off and landing (VTOL) which integrates several LO2-LCH 4 systems that are being devised in-house. The vehicle will serve as a testbed for the parallel operation of these propulsion systems while being fed from common propellant tanks. The following work describes the efforts done at the cSETR to develop the first prototype of the vehicle as well as the plan to move forward in the design of the subsequent prototypes that will lead to a flight vehicle. In order to ensure an eventual smooth integration of the different subsystems that will form part of Janus, requirements were defined for each individual subsystem as well as the vehicle as a whole. Preliminary testing procedures and layouts have also been developed and will be discussed to detail in this text. Furthermore, the current endeavors in the design of each subsystem and the way that they interact with one another within the lander will be explained.

  8. Mathematical modeling of control subsystems for CELSS: Application to diet

    Science.gov (United States)

    Waleh, Ahmad; Nguyen, Thoi K.; Kanevsky, Valery

    1991-01-01

    The dynamic control of a Closed Ecological Life Support System (CELSS) in a closed space habitat is of critical importance. The development of a practical method of control is also a necessary step for the selection and design of realistic subsystems and processors for a CELSS. Diet is one of the dynamic factors that strongly influences, and is influenced, by the operational states of all major CELSS subsystems. The problems of design and maintenance of a stable diet must be obtained from well characterized expert subsystems. The general description of a mathematical model that forms the basis of an expert control program for a CELSS is described. The formulation is expressed in terms of a complete set of time dependent canonical variables. System representation is dynamic and includes time dependent storage buffers. The details of the algorithm are described. The steady state results of the application of the method for representative diets made from wheat, potato, and soybean are presented.

  9. Double Shell Tank (DST) Transfer Piping Subsystem Specification

    International Nuclear Information System (INIS)

    GRAVES, C.E.

    2000-01-01

    This specification establishes the performance requirements and provides references to the requisite codes and standards to be applied during design of the Double-Shell Tank (DST) Transfer Piping Subsystem that supports the first phase of Waste Feed Delivery. This specification establishes the performance requirements and provides references to the requisite codes and standards to be applied during design of the Double-Shell Tank (DST) Transfer Piping Subsystem that supports the first phase of waste feed delivery. This subsystem transfers waste between transfer-associated structures (pits) and to the River Protection Project (RPP) Privatization Contractor Facility where it will be processed into an immobilized waste form. This specification is intended to be the basis for new projects/installations (W-521, etc.). This specification is not intended to retroactively affect previously established project design criteria without specific direction by the program

  10. The complete Heyting algebra of subsystems and contextuality

    International Nuclear Information System (INIS)

    Vourdas, A.

    2013-01-01

    The finite set of subsystems of a finite quantum system with variables in Z(n), is studied as a Heyting algebra. The physical meaning of the logical connectives is discussed. It is shown that disjunction of subsystems is more general concept than superposition. Consequently, the quantum probabilities related to commuting projectors in the subsystems, are incompatible with associativity of the join in the Heyting algebra, unless if the variables belong to the same chain. This leads to contextuality, which in the present formalism has as contexts, the chains in the Heyting algebra. Logical Bell inequalities, which contain “Heyting factors,” are discussed. The formalism is also applied to the infinite set of all finite quantum systems, which is appropriately enlarged in order to become a complete Heyting algebra

  11. Embedded Thermal Control for Subsystems for Next Generation Spacecraft Applications

    Science.gov (United States)

    Didion, Jeffrey R.

    2015-01-01

    Thermal Fluids and Analysis Workshop, Silver Spring MD NCTS 21070-15. NASA, the Defense Department and commercial interests are actively engaged in developing miniaturized spacecraft systems and scientific instruments to leverage smaller cheaper spacecraft form factors such as CubeSats. This paper outlines research and development efforts among Goddard Space Flight Center personnel and its several partners to develop innovative embedded thermal control subsystems. Embedded thermal control subsystems is a cross cutting enabling technology integrating advanced manufacturing techniques to develop multifunctional intelligent structures to reduce Size, Weight and Power (SWaP) consumption of both the thermal control subsystem and overall spacecraft. Embedded thermal control subsystems permit heat acquisition and rejection at higher temperatures than state of the art systems by employing both advanced heat transfer equipment (integrated heat exchangers) and high heat transfer phenomena. The Goddard Space Flight Center Thermal Engineering Branch has active investigations seeking to characterize advanced thermal control systems for near term spacecraft missions. The embedded thermal control subsystem development effort consists of fundamental research as well as development of breadboard and prototype hardware and spaceflight validation efforts. This paper will outline relevant fundamental investigations of micro-scale heat transfer and electrically driven liquid film boiling. The hardware development efforts focus upon silicon based high heat flux applications (electronic chips, power electronics etc.) and multifunctional structures. Flight validation efforts include variable gravity campaigns and a proposed CubeSat based flight demonstration of a breadboard embedded thermal control system. The CubeSat investigation is technology demonstration will characterize in long-term low earth orbit a breadboard embedded thermal subsystem and its individual components to develop

  12. Ground test facility for nuclear testing of space reactor subsystems

    International Nuclear Information System (INIS)

    Quapp, W.J.; Watts, K.D.

    1985-01-01

    Two major reactor facilities at the INEL have been identified as easily adaptable for supporting the nuclear testing of the SP-100 reactor subsystem. They are the Engineering Test Reactor (ETR) and the Loss of Fluid Test Reactor (LOFT). In addition, there are machine shops, analytical laboratories, hot cells, and the supporting services (fire protection, safety, security, medical, waste management, etc.) necessary to conducting a nuclear test program. This paper presents the conceptual approach for modifying these reactor facilities for the ground engineering test facility for the SP-100 nuclear subsystem. 4 figs

  13. Coexistence of uniquely ergodic subsystems of interval mapping

    International Nuclear Information System (INIS)

    Ye Xiangdong.

    1991-10-01

    The purpose of this paper is to show that uniquely ergodic subsystems of interval mapping also coexist in the same way as minimal sets do. To do this we give some notations in section 2. In section 3 we define D-function of a uniquely ergodic system and show its basic properties. We prove the coexistence of uniquely ergodic subsystems of interval mapping in section 4. Lastly we give the examples of uniquely ergodic systems with given D-functions in section 5. 27 refs

  14. Optomechanical design of TMT NFIRAOS Subsystems at INO

    Science.gov (United States)

    Lamontagne, Frédéric; Desnoyers, Nichola; Grenier, Martin; Cottin, Pierre; Leclerc, Mélanie; Martin, Olivier; Buteau-Vaillancourt, Louis; Boucher, Marc-André; Nash, Reston; Lardière, Olivier; Andersen, David; Atwood, Jenny; Hill, Alexis; Byrnes, Peter W. G.; Herriot, Glen; Fitzsimmons, Joeleff; Véran, Jean-Pierre

    2017-08-01

    The adaptive optics system for the Thirty Meter Telescope (TMT) is the Narrow-Field InfraRed Adaptive Optics System (NFIRAOS). Recently, INO has been involved in the optomechanical design of several subsystems of NFIRAOS, including the Instrument Selection Mirror (ISM), the NFIRAOS Beamsplitters (NBS), and the NFIRAOS Source Simulator system (NSS) comprising the Focal Plane Mask (FPM), the Laser Guide Star (LGS) sources, and the Natural Guide Star (NGS) sources. This paper presents an overview of these subsystems and the optomechanical design approaches used to meet the optical performance requirements under environmental constraints.

  15. Software Testbed for Developing and Evaluating Integrated Autonomous Subsystems

    Science.gov (United States)

    Ong, James; Remolina, Emilio; Prompt, Axel; Robinson, Peter; Sweet, Adam; Nishikawa, David

    2015-01-01

    To implement fault tolerant autonomy in future space systems, it will be necessary to integrate planning, adaptive control, and state estimation subsystems. However, integrating these subsystems is difficult, time-consuming, and error-prone. This paper describes Intelliface/ADAPT, a software testbed that helps researchers develop and test alternative strategies for integrating planning, execution, and diagnosis subsystems more quickly and easily. The testbed's architecture, graphical data displays, and implementations of the integrated subsystems support easy plug and play of alternate components to support research and development in fault-tolerant control of autonomous vehicles and operations support systems. Intelliface/ADAPT controls NASA's Advanced Diagnostics and Prognostics Testbed (ADAPT), which comprises batteries, electrical loads (fans, pumps, and lights), relays, circuit breakers, invertors, and sensors. During plan execution, an experimentor can inject faults into the ADAPT testbed by tripping circuit breakers, changing fan speed settings, and closing valves to restrict fluid flow. The diagnostic subsystem, based on NASA's Hybrid Diagnosis Engine (HyDE), detects and isolates these faults to determine the new state of the plant, ADAPT. Intelliface/ADAPT then updates its model of the ADAPT system's resources and determines whether the current plan can be executed using the reduced resources. If not, the planning subsystem generates a new plan that reschedules tasks, reconfigures ADAPT, and reassigns the use of ADAPT resources as needed to work around the fault. The resource model, planning domain model, and planning goals are expressed using NASA's Action Notation Modeling Language (ANML). Parts of the ANML model are generated automatically, and other parts are constructed by hand using the Planning Model Integrated Development Environment, a visual Eclipse-based IDE that accelerates ANML model development. Because native ANML planners are currently

  16. Novel Design Aspects of the Space Technology 5 Mechanical Subsystem

    Science.gov (United States)

    Rossoni, Peter; McGill, William

    2003-01-01

    This paper describes several novel design elements of the Space Technology 5 (ST5) spacecraft mechanical subsystem. The spacecraft structure itself takes a significant step in integrating electronics into the primary structure. The deployment system restrains the spacecraft during launch and imparts a predetermined spin rate upon release from its secondary payload accommodations. The deployable instrument boom incorporates some traditional as well as new techniques for lightweight and stiffness. Analysis and test techniques used to validate these technologies are described. Numerous design choices were necessitated due to the compact spacecraft size and strict mechanical subsystem requirements.

  17. Nondestructive examination of the Tropical Rainfall Measuring Mission (TRMM) reaction control subsystem (RCS) propellant tanks

    Science.gov (United States)

    Free, James M.

    1993-01-01

    This paper assesses the feasibility of using eddy current nondestructive examination to determine flaw sizes in completely assembled hydrazine propellant tanks. The study was performed by the NASA Goddard Space Flight Center for the Tropical Rainfall Measuring Mission (TRMM) project to help determine whether existing propellant tanks could meet the fracture analysis requirements of the current pressure vessel specification, MIL-STD-1522A and, therefore be used on the TRMM spacecraft. After evaluating several nondestructive test methods, eddy current testing was selected as the most promising method for determining flaw sizes on external and internal surfaces of completely assembled tanks. Tests were conducted to confirm the detection capability of the eddy current NDE, procedures were developed to inspect two candidate tanks, and the test support equipment was designed. The non-spherical tank eddy current NDE test program was terminated when the decision was made to procure new tanks for the TRMM propulsion subsystem. The information on the development phase of this test program is presented in this paper as a reference for future investigation on the subject.

  18. 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 ...

  19. 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.

  20. Solar Electric Propulsion Technology Development for Electric Propulsion

    Science.gov (United States)

    Mercer, Carolyn R.; Kerslake, Thomas W.; Scheidegger, Robert J.; Woodworth, Andrew A.; Lauenstein, Jean-Marie

    2015-01-01

    NASA is developing technologies to prepare for human exploration missions to Mars. Solar electric propulsion (SEP) systems are expected to enable a new cost effective means to deliver cargo to the Mars surface. Nearer term missions to Mars moons or near-Earth asteroids can be used to both develop and demonstrate the needed technology for these future Mars missions while demonstrating new capabilities in their own right. This presentation discusses recent technology development accomplishments for high power, high voltage solar arrays and power management that enable a new class of SEP missions.

  1. Seismic Safety Margins Research Program. Phase 1. Project V. Structural sub-system response: subsystem response review

    International Nuclear Information System (INIS)

    Fogelquist, J.; Kaul, M.K.; Koppe, R.; Tagart, S.W. Jr.; Thailer, H.; Uffer, R.

    1980-03-01

    This project is directed toward a portion of the Seismic Safety Margins Research Program which includes one link in the seismic methodology chain. The link addressed here is the structural subsystem dynamic response which consists of those components and systems whose behavior is often determined decoupled from the major structural response. Typically the mathematical model utilized for the major structural response will include only the mass effects of the subsystem and the main model is used to produce the support motion inputs for subsystem seismic qualification. The main questions addressed in this report have to do with the seismic response uncertainty of safety-related components or equipment whose seismic qualification is performed by (a) analysis, (b) tests, or (c) combinations of analysis and tests, and where the seismic input is assumed to have no uncertainty

  2. 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)

  3. 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

  4. 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.

  5. 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...

  6. 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.)

  7. Cascade Distillation Subsystem Development: Progress Toward a Distillation Comparison Test

    Science.gov (United States)

    Callahan, M. R.; Lubman, A.; Pickering, Karen D.

    2009-01-01

    Recovery of potable water from wastewater is essential for the success of long-duration manned missions to the Moon and Mars. Honeywell International and a team from NASA Johnson Space Center (JSC) are developing a wastewater processing subsystem that is based on centrifugal vacuum distillation. The wastewater processor, referred to as the Cascade Distillation Subsystem (CDS), utilizes an innovative and efficient multistage thermodynamic process to produce purified water. The rotary centrifugal design of the system also provides gas/liquid phase separation and liquid transport under microgravity conditions. A five-stage subsystem unit has been designed, built, delivered and integrated into the NASA JSC Advanced Water Recovery Systems Development Facility for performance testing. A major test objective of the project is to demonstrate the advancement of the CDS technology from the breadboard level to a subsystem level unit. An initial round of CDS performance testing was completed in fiscal year (FY) 2008. Based on FY08 testing, the system is now in development to support an Exploration Life Support (ELS) Project distillation comparison test expected to begin in early 2009. As part of the project objectives planned for FY09, the system will be reconfigured to support the ELS comparison test. The CDS will then be challenged with a series of human-gene-rated waste streams representative of those anticipated for a lunar outpost. This paper provides a description of the CDS technology, a status of the current project activities, and data on the system s performance to date.

  8. Mark 4A DSN receiver-exciter and transmitter subsystems

    Science.gov (United States)

    Wick, M. R.

    1986-01-01

    The present configuration of the Mark 4A DSN Receiver-Exciter and Transmitter Subsystems is described. Functional requirements and key characteristics are given to show the differences in the capabilities required by the Networks Consolidation task for combined High Earth Orbiter and Deep Space Network tracking support.

  9. Effector-Triggered Self-Replication in Coupled Subsystems

    NARCIS (Netherlands)

    Komáromy, Dávid; Tezcan, Meniz; Schaeffer, Gaël; Marić, Ivana; Otto, Sijbren

    2017-01-01

    In living systems processes like genome duplication and cell division are carefully synchronized through subsystem coupling. If we are to create life de novo, similar control over essential processes such as self-replication need to be developed. Here we report that coupling two dynamic

  10. Computer Simulation of the Circulation Subsystem of a Library

    Science.gov (United States)

    Shaw, W. M., Jr.

    1975-01-01

    When circulation data are used as input parameters for a computer simulation of a library's circulation subsystem, the results of the simulation provide information on book availability and delays. The model may be used to simulate alternative loan policies. (Author/LS)

  11. Double-Shell Tank (DST) Diluent and Flush Subsystem Specification

    International Nuclear Information System (INIS)

    GRAVES, C.E.

    2000-01-01

    The Double-Shell Tank (DST) Diluent and Flush Subsystem is intended to support Waste Feed Delivery. The DST Diluent and Flush Subsystem specification describes the relationship of this system with the DST System, describes the functions that must be performed by the system, and establishes the performance requirements to be applied to the design of the system. It also provides references for the requisite codes and standards. The DST Diluent and Flush Subsystem will treat the waste for a more favorable waste transfer. This will be accomplished by diluting the waste, dissolving the soluble portion of the waste, and flushing waste residuals from the transfer line. The Diluent and Flush Subsystem will consist of the following: The Diluent and Flush Station(s) where chemicals will be off-loaded, temporarily stored, mixed as necessary, heated, and metered to the delivery system; and A piping delivery system to deliver the chemicals to the appropriate valve or pump pit Associated support structures. This specification is intended to be the basis for new projects/installations. This specification is not intended to retroactively affect previously established project design criteria without specific direction by the program

  12. A shell-model calculation in terms of correlated subsystems

    International Nuclear Information System (INIS)

    Boisson, J.P.; Silvestre-Brac, B.

    1979-01-01

    A method for solving the shell-model equations in terms of a basis which includes correlated subsystems is presented. It is shown that the method allows drastic truncations of the basis to be made. The corresponding calculations are easy to perform and can be carried out rapidly

  13. Compliance with NRC subsystem requirements in the repository licensing process

    International Nuclear Information System (INIS)

    Minwalla, H.

    1994-01-01

    Section 121 of the Nuclear Waste Policy Act of 1982 requires the Nuclear Regulatory Commission (Commission) to issue technical requirements and criteria, for the use of a system of multiple barriers in the design of the repository, that are not inconsistent with any comparable standard promulgated by the Environmental Protection Agency (EPA). The Administrator of the EPA is required to promulgate generally applicable standards for protection of the general environment from offsite releases from radioactive material in repositories. The Commission's regulations pertaining to geologic repositories are provided in 10 CFR part 60. The Commission has provided in 10 CFR 60.112 the overall post-closure system performance objective which is used to demonstrate compliance with the EPA high-level waste (HLW) disposal standard. In addition, the Commission has provided, in 10 CFR 60.113, subsystem performance requirements for substantially complete containment, fractional release rate, and groundwater travel time; however, none of these subsystem performance requirements have a causal technical nexus with the EPA HLW disposal standard. This paper examines the issue of compliance with the conflicting dual regulatory role of subsystem performance requirements in the repository licensing process and recommends several approaches that would appropriately define the role of subsystem performance requirements in the repository licensing process

  14. Charactering lidar optical subsystem using four quadrants method

    Science.gov (United States)

    Tian, Xiaomin; Liu, Dong; Xu, Jiwei; Wang, Zhenzhu; Wang, Bangxin; Wu, Decheng; Zhong, Zhiqing; Xie, Chenbo; Wang, Yingjian

    2018-02-01

    Lidar is a kind of active optical remote sensing instruments , can be applied to sound atmosphere with a high spatial and temporal resolution. Many parameter of atmosphere can be get by using different inverse algorithm with lidar backscatter signal. The basic setup of a lidar consist of a transmitter and a receiver. To make sure the quality of lidar signal data, the lidar must be calibrated before being used to measure the atmospheric variables. It is really significant to character and analyze lidar optical subsystem because a well equiped lidar optical subsystem contributes to high quality lidar signal data. we pay close attention to telecover test to character and analyze lidar optical subsystem.The telecover test is called four quadrants method consisting in dividing the telescope aperture in four quarants. when a lidar is well configured with lidar optical subsystem, the normalized signal from four qudrants will agree with each other on some level. Testing our WARL-II lidar by four quadrants method ,we find the signals of the four basically consistent with each other both in near range and in far range. But in detail, the signals in near range have some slight distinctions resulting from overlap function, some signals distinctions are induced by atmospheric instability.

  15. 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

  16. 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.

  17. Space storable propulsion components development

    Science.gov (United States)

    Hagler, R., Jr.

    1982-01-01

    The current development status of components to control the flow of propellants (liquid fluorine and hydrazine) in a demonstration space storable propulsion system is discussed. The criteria which determined the designs for the pressure regulator, explosive-actuated valves, propellant shutoff valve, latching solenoid-actuated valve and propellant filter are presented. The test philosophy that was followed during component development is outlined. The results from compatibility demonstrations for reusable connectors, flange seals, and CRES/Ti-6Al4V transition tubes and the evaluations of processes for welding (hand-held TIG, automated TIG, and EB), cleaning for fluorine service, and decontamination after fluorine exposure are described.

  18. Laser Diagnostics for Spacecraft Propulsion

    Science.gov (United States)

    2015-10-13

    for public release; distribution unlimited.  AFTC/PA Clearance No.  XXXX 3 Motivation • Many satellite propulsion technologies were developed in the...distribution unlimited.  AFTC/PA Clearance No.  XXXX Propellant Catalyst Bed Decomposition Chamber Thrust Chamber 5 Diode Laser Absorption Spectroscopy Beer...Hydrazine Thruster NH3 Iν(L)Iν0 Ramp t I L DISTRIBUTION A:  Approved for public release; distribution unlimited.  AFTC/PA Clearance No.  XXXX 6 Wavelength

  19. Impact of the "faster better cheaper" requirements for satellites components/subsystems on SEP organisation and processes.

    Science.gov (United States)

    Pages, X.

    2000-03-01

    in the early 90's in Hall propulsion through numerous partnership with Russian, American and Italian companies and/or universities. A mature knowledge of Hall thruster functioning and technologies helped SEP to recently complete a successful qualification of their first Hall thruster. "PPS 1350" which will be in flight aboard STENTOR French technological satellite in year 2000. A cost reduction research of this new product was held in parallel to the PPS 1350 qualification, taking into account all the lessons learnt during PPS 1350 development. Its major outputs are the numerous simplifications that were found leading to dramatic cost reductions without impairing thruster performances (reliability was even improved). This improved thruster is today very favorably considered by several primes for small low earth orbit satellites. Hydrazine propulsion is an other example. In this field, which SEP decided in 1996 to accompany their customers in their move from large traditional satellites (SPOT/ERS family) to smaller, cheaper ones. To do so, SEP proposed a monolithic propulsion subsystem (patented design) in which all usual propulsion subsystem assembly devices (piping, supports, brackets…) are avoided, components being directly mounted on the propellant tank. Significant costs reduction could be offered to customers thanks to this innovation. Along with the hydrazine propulsion, SEP also modernised their solar array drive mechanisms the SEPTA's® — SEPTA 31 was qualified end 1998 and will have its maiden flight aboard CNES/ALCATEL JASONI small earth observation satellite. In summary, SEP had to make important changes in order to adapt to the market evolution, which occurred in the early 90's. There efforts implied as well organization as processes as products. First outputs are significant cost reduction; in line will the objectives. First hardware of this new generation will fly in year 2000.

  20. Characterization of the power and efficiency of Stirling engine subsystems

    International Nuclear Information System (INIS)

    García, D.; González, M.A.; Prieto, J.I.; Herrero, S.; López, S.; Mesonero, I.; Villasante, C.

    2014-01-01

    Highlights: • We review experimental data from a V160 engine developed for cogeneration. • We also investigate the V161 solar engine. • The possible margin of improvement is evaluated for each subsystem. • The procedure is based on similarity models and thermodynamic models. • The procedure may be of general interest for other prototypes. - Abstract: The development of systems based on Stirling machines is limited by the lack of data about the performance of the various subsystems that are located between the input and output power sections. The measurement of some of the variables used to characterise these internal subsystems presents difficulties, particularly in the working gas circuit and the drive mechanism, which causes experimental reports to rarely be comprehensive enough for analysing the whole performance of the machine. In this article, we review experimental data from a V160 engine developed for cogeneration to evaluate the general validity; we also investigate one of the most successful prototypes used in dish-Stirling systems, the V161 engine, for which a seemingly small mechanical efficiency value has been recently predicted. The procedure described in this article allows the possible margin of improvement to be evaluated for each subsystem. The procedure is based on similarity models, which have been previously developed through experimental data from very different prototypes. Thermodynamic models for the gas circuit are also considered. Deduced characteristic curves show that both prototypes have an advanced degree of development as evidenced by relatively high efficiencies for each subsystem. The analyses are examples that demonstrate the qualities of dimensionless numbers in representing physical phenomena with maximum generality and physical meaning

  1. Power processing for electric propulsion

    Science.gov (United States)

    Finke, R. C.; Herron, B. G.; Gant, G. D.

    1975-01-01

    The potential of achieving up to 30 per cent more spacecraft payload or 50 per cent more useful operating life by the use of electric propulsion in place of conventional cold gas or hydrazine systems in science, communications, and earth applications spacecraft is a compelling reason to consider the inclusion of electric thruster systems in new spacecraft design. The propulsion requirements of such spacecraft dictate a wide range of thruster power levels and operational lifetimes, which must be matched by lightweight, efficient, and reliable thruster power processing systems. This paper will present electron bombardment ion thruster requirements; review the performance characteristics of present power processing systems; discuss design philosophies and alternatives in areas such as inverter type, arc protection, and control methods; and project future performance potentials for meeting goals in the areas of power processor weight (10 kg/kW), efficiency (approaching 92 per cent), reliability (0.96 for 15,000 hr), and thermal control capability (0.3 to 5 AU).

  2. Gasdynamic Mirror Fusion Propulsion Experiment

    Science.gov (United States)

    Emrich, Bill; Rodgers, Stephen L. (Technical Monitor)

    2000-01-01

    A gasdynamic mirror (GDM) fusion propulsion experiment is currently being constructed at the NASA Marshall Space Flight Center (MSFC) to test the feasibility of this particular type of fusion device. Because of the open magnetic field line configuration of mirror fusion devices, they are particularly well suited for propulsion system applications since they allow for the easy ejection of thrust producing plasma. Currently, the MSFC GDM is constructed in three segments. The vacuum chamber mirror segment, the plasma injector mirror segment, and the main plasma chamber segment. Enough magnets are currently available to construct up to three main plasma chamber segments. The mirror segments are also segmented such that they can be expanded to accommodate new end plugging strategies with out requiring the disassembly of the entire mirror segment. The plasma for the experiment is generated in a microwave cavity located between the main magnets and the mirror magnets. Ion heating is accomplished through ambipolar diffusion. The objective of the experiment is to investigate the stability characteristics of the gasdynamic mirror and to map a region of parameter space within which the plasma can be confined in a stable steady state configuration. The mirror ratio, plasma density, and plasma "b" will be varied over a range of values and measurements subsequently taken to determine the degree of plasma stability.

  3. Development of superconducting ship propulsion system

    International Nuclear Information System (INIS)

    Sakuraba, Junji; Mori, Hiroyuki; Hata, Fumiaki; Sotooka, Koukichi

    1991-01-01

    When we plan displacement-type monohull high speed vessels, it is difficult to get the hull form with the wave-making resistance minimum, because the stern shape is restricted by arrangement of propulsive machines and shafts. A small-sized and light-weight propulsive machines will reduce the limit to full form design. Superconducting technology will have capability of realizing the small-sized and light-weight propulsion motor. The superconducting electric propulsion system which is composed of superconducting propulsion motors and generators, seems to be an ideal propulsion system for future vehicles. We have constructed a 480 kW superconducting DC homopolar laboratory test motor for developing this propulsion system. The characteristic of this motor is that it has a superconducting field winding and a segmented armature drum. The superconducting field winding which operates in the persistent current mode, is cooled by a condensation heat exchanger and helium refigerating system built into the cryostat of the superconducting field winding. The operating parameters of this motor agreed well with the design parameters. Using the design concepts of this motor, we have conceptually designed a 150,000-200,000 PS superconducting electric propulsive system for a displacement-type monohull high speed ship. (author)

  4. Integrated Propulsion Data System Public Web Site

    Science.gov (United States)

    Hamilton, Kimberly

    2001-01-01

    The Integrated Propulsion Data System's (IPDS) focus is to provide technologically-advanced philosophies of doing business at SSC that will enhance the existing operations, engineering and management strategies and provide insight and metrics to assess their daily impacts, especially as related to the Propulsion Test Directorate testing scenarios for the 21st Century.

  5. 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...

  6. Research Activities on Special Propulsion in BUAA

    International Nuclear Information System (INIS)

    Tang Haibin; Wang Haixing; Liu Chang; Xiang Min; Yao Jie; Liu Yu

    2007-01-01

    An overview is presented of special propulsion research carried out in Beijing University of Aeronautics and Astronautics of China. The research activities are supported by NSFC (National Natural Science Foundation of China), other governmental agencies and industrial partners, which include experimental, analytical and numerical work related to arcjet thrusters, ion thrusters, plasma sail and other new concept propulsions

  7. Propulsive efficiency and non- expert swimmers performance

    Directory of Open Access Journals (Sweden)

    Tiago Barbosa

    2009-12-01

    Full Text Available Propulsive efficiency is one of the most interesting issues for competitive swimming researchers, has it presents significant relationships with the swimmer’s biophysical behavior and his/her performance. Although propulsive efficiency is a variable that has been quite studied in elite swimmers, there is no research on this issue in young and non-expert swimmers. Thus, the aim of this study was to: (i estimate the propulsive efficiency on non-expert swimmers; (ii identify biomechanical and anthropometrical parameters that are associated with propulsive efficiency; (iii identify the association between the propulsive efficiency and swim performance. Twenty-eight non-expert swimmers participated on this study. It was assessed the propulsive efficiency, biomechanical and anthropometrical parameters, as well as, the swim performance. The propulsive efficiency of non-expert swimmers is lower than data reported in the literature to higher competitive levels swimmers and there are no significant differences between boys and girls. It was also noted that several biomechanical and anthropometrical parameters, as well as, the swim performance are associated with the propulsive efficiency.

  8. Powersail High Power Propulsion System Design Study

    Science.gov (United States)

    Gulczinski, Frank S., III

    2000-11-01

    A desire by the United States Air Force to exploit the space environment has led to a need for increased on-orbit electrical power availability. To enable this, the Air Force Research Laboratory Space Vehicles Directorate (AFRL/ VS) is developing Powersail: a two-phased program to demonstrate high power (100 kW to 1 MW) capability in space using a deployable, flexible solar array connected to the host spacecraft using a slack umbilical. The first phase will be a proof-of-concept demonstration at 50 kW, followed by the second phase, an operational system at full power. In support of this program, the AFRL propulsion Directorate's Spacecraft Propulsion Branch (AFRL/PRS ) at Edwards AFB has commissioned a design study of the Powersail High Power Propulsion System. The purpose of this study, the results of which are summarized in this paper, is to perform mission and design trades to identify potential full-power applications (both near-Earth and interplanetary) and the corresponding propulsion system requirements and design. The design study shall farther identify a suitable low power demonstration flight that maximizes risk reduction for the fully operational system. This propulsion system is expected to be threefold: (1) primary propulsion for moving the entire vehicle, (2) a propulsion unit that maintains the solar array position relative to the host spacecraft, and (3) control propulsion for maintaining proper orientation for the flexible solar array.

  9. 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...

  10. Ablative Laser Propulsion: An Update, Part I

    International Nuclear Information System (INIS)

    Pakhomov, Andrew V.; Cohen, Timothy; Lin Jun; Thompson, M. Shane; Herren, Kenneth A.

    2004-01-01

    This paper presents an updated review of studies on Ablative Laser Propulsion conducted by the Laser Propulsion Group (LPG) at the University of Alabama in Huntsville. In particular, we describe the newest results of our experimental study of specific impulses and coupling coefficients achieved by double-pulsed ablation of graphite, aluminum, copper and lead targets

  11. Max Launch Abort System (MLAS) Pad Abort Test Vehicle (PATV) II Attitude Control System (ACS) Integration and Pressurization Subsystem Dynamic Random Vibration Analysis

    Science.gov (United States)

    Ekrami, Yasamin; Cook, Joseph S.

    2011-01-01

    In order to mitigate catastrophic failures on future generation space vehicles, engineers at the National Aeronautics and Space Administration have begun to integrate a novel crew abort systems that could pull a crew module away in case of an emergency at the launch pad or during ascent. The Max Launch Abort System (MLAS) is a recent test vehicle that was designed as an alternative to the baseline Orion Launch Abort System (LAS) to demonstrate the performance of a "tower-less" LAS configuration under abort conditions. The MLAS II test vehicle will execute a propulsive coast stabilization maneuver during abort to control the vehicles trajectory and thrust. To accomplish this, the spacecraft will integrate an Attitude Control System (ACS) with eight hypergolic monomethyl hydrazine liquid propulsion engines that are capable of operating in a quick pulsing mode. Two main elements of the ACS include a propellant distribution subsystem and a pressurization subsystem to regulate the flow of pressurized gas to the propellant tanks and the engines. The CAD assembly of the Attitude Control System (ACS) was configured and integrated into the Launch Abort Vehicle (LAV) design. A dynamic random vibration analysis was conducted on the Main Propulsion System (MPS) helium pressurization panels to assess the response of the panel and its components under increased gravitational acceleration loads during flight. The results indicated that the panels fundamental and natural frequencies were farther from the maximum Acceleration Spectral Density (ASD) vibrations which were in the range of 150-300 Hz. These values will direct how the components will be packaged in the vehicle to reduce the effects high gravitational loads.

  12. National Ingition Facility subsystem design requirements optical mounts SSDR 1.4.4

    International Nuclear Information System (INIS)

    Richardson, M.

    1996-01-01

    This SSDR establishes the performance, design, development and test requirements for NIF Beam Transport Optomechanical Subsystems. optomechanical Subsystems includes the mounts for the beam transport mirrors, LMl - LM8, the polarizer mount, and the spatial filter lens mounts

  13. Double Shell Tank (DST) Transfer Pump Subsystem Specification

    International Nuclear Information System (INIS)

    GRAVES, C.E.

    2001-01-01

    This specification establishes the performance requirements and provides the references to the requisite codes and standards to be applied during the design of the Double-Shell Tank (DST) Transfer Pump Subsystem that supports the first phase of waste feed delivery (WFD). The DST Transfer Pump Subsystem consists of a pump for supernatant and/or slurry transfer for the DSTs that will be retrieved during the Phase 1 WFD operations. This system is used to transfer low-activity waste (LAW) and high-level waste (HLW) to designated DST staging tanks. It also will deliver blended LAW and HLW feed from these staging tanks to the River Protection Project (RPP) Waste Treatment Plant where it will be processed into an immobilized waste form. This specification is intended to be the basis for new projects/installations (W-521, etc.). This specification is not intended to retroactively affect previously established project design criteria without specific direction by the program

  14. Recovering Intrinsic Fragmental Vibrations Using the Generalized Subsystem Vibrational Analysis.

    Science.gov (United States)

    Tao, Yunwen; Tian, Chuan; Verma, Niraj; Zou, Wenli; Wang, Chao; Cremer, Dieter; Kraka, Elfi

    2018-05-08

    Normal vibrational modes are generally delocalized over the molecular system, which makes it difficult to assign certain vibrations to specific fragments or functional groups. We introduce a new approach, the Generalized Subsystem Vibrational Analysis (GSVA), to extract the intrinsic fragmental vibrations of any fragment/subsystem from the whole system via the evaluation of the corresponding effective Hessian matrix. The retention of the curvature information with regard to the potential energy surface for the effective Hessian matrix endows our approach with a concrete physical basis and enables the normal vibrational modes of different molecular systems to be legitimately comparable. Furthermore, the intrinsic fragmental vibrations act as a new link between the Konkoli-Cremer local vibrational modes and the normal vibrational modes.

  15. Measurement system as a subsystem of the quality management system

    Directory of Open Access Journals (Sweden)

    Ľubica Floreková

    2006-12-01

    Full Text Available Each measurement system and a control principle must be based on certain facts about the system behaviour (what, operation (how and structure (why. Each system is distributed into subsystems that provide an input for the next subsystem. For each system, start is important the begin, that means system characteristics, collecting of data, its hierarchy and the processes distribution.A measurement system (based on the chapter 8 of the standard ISO 9001:2000 Quality management system, requirements defines the measurement, analysis and improvement for each organization in order to present the products conformity, the quality management system conformity guarantee and for the continuously permanent improvement of effectivity, efficiency and economy of quality management system.

  16. Subsystem software for TSTA [Tritium Systems Test Assembly

    International Nuclear Information System (INIS)

    Mann, L.W.; Claborn, G.W.; Nielson, C.W.

    1987-01-01

    The Subsystem Control Software at the Tritium System Test Assembly (TSTA) must control sophisticated chemical processes through the physical operation of valves, motor controllers, gas sampling devices, thermocouples, pressure transducers, and similar devices. Such control software has to be capable of passing stringent quality assurance (QA) criteria to provide for the safe handling of significant amounts of tritium on a routine basis. Since many of the chemical processes and physical components are experimental, the control software has to be flexible enough to allow for trial/error learning curve, but still protect the environment and personnel from exposure to unsafe levels of radiation. The software at TSTA is implemented in several levels as described in a preceding paper in these proceedings. This paper depends on information given in the preceding paper for understanding. The top level is the Subsystem Control level

  17. Solar Electric Propulsion (SEP) Tug Power System Considerations

    Science.gov (United States)

    Kerslake, Thomas W.; Bury, Kristen M.; Hojinicki, Jeffrey S.; Sajdak, Adam M.; Scheiddegger, Robert J.

    2011-01-01

    Solar electric propulsion (SEP) technology is truly at the "intersection of commercial and military space" as well as the intersection of NASA robotic and human space missions. Building on the use of SEP for geosynchronous spacecraft station keeping, there are numerous potential commercial and military mission applications for SEP stages operating in Earth orbit. At NASA, there is a resurgence of interest in robotic SEP missions for Earth orbit raising applications, 1-AU class heliocentric missions to near Earth objects (NEOs) and SEP spacecraft technology demonstrations. Beyond these nearer term robotic missions, potential future human space flight missions to NEOs with high-power SEP stages are being considered. To enhance or enable this broad class of commercial, military and NASA missions, advancements in the power level and performance of SEP technologies are needed. This presentation will focus on design considerations for the solar photovoltaic array (PVA) and electric power system (EPS) vital to the design and operation of an SEP stage. The engineering and programmatic pros and cons of various PVA and EPS technologies and architectures will be discussed in the context of operating voltage and power levels. The impacts of PVA and EPS design options on the remaining SEP stage subsystem designs, as well as spacecraft operations, will also be discussed.

  18. 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

  19. LightNVM: The Linux Open-Channel SSD Subsystem

    DEFF Research Database (Denmark)

    Bjørling, Matias; Gonzalez, Javier; Bonnet, Philippe

    2017-01-01

    resource utilization. We propose that SSD management trade-offs should be handled through Open-Channel SSDs, a new class of SSDs, that give hosts control over their internals. We present our experience building LightNVM, the Linux Open-Channel SSD subsystem. We introduce a new Physical Page Ad- dress I...... to limit read latency variability and that it can be customized to achieve predictable I/O latencies....

  20. CAMAC subsystem and user context utilities in ngdp framework

    International Nuclear Information System (INIS)

    Isupov, A.Yu.

    2010-01-01

    The ngdp framework advanced topics are described. Namely, we consider work with CAMAC hardware, 'selfflow' nodes for the data acquisition systems with the As-Soon-As-Possible policy, ng m m(4) as an alternative to ng s ocket(4), the control subsystem, user context utilities, events representation for the ROOT package, test and debug nodes, possible advancements for netgraph(4), etc. It is shown that the ngdp is suitable for building lightweight DAQ systems to handle CAMAC

  1. Subsystem for control of isotope production with linear electron accelerator

    CERN Document Server

    Karasyov, S P; Uvarov, V L

    2001-01-01

    In this report the high-current LINAC subsystem for diagnostic and monitoring the basic technological parameters of isotope production (energy flux of Bremsstrahlung photons and absorbed doze in the target,target activity, temperature and consumption of water cooling the converter and target) is described.T he parallel printer port (LPT) of the personal computer is proposed to use as an interface with the measurement channels.

  2. Photovoltaic subsystem optimization and design tradeoff study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Stolte, W.J.

    1982-03-01

    Tradeoffs and subsystem choices are examined in photovoltaic array subfield design, power-conditioning sizing and selection, roof- and ground-mounted structure installation, energy loss, operating voltage, power conditioning cost, and subfield size. Line- and self-commutated power conditioning options are analyzed to determine the most cost-effective technology in the megawatt power range. Methods for reducing field installation of flat panels and roof mounting of intermediate load centers are discussed, including the cost of retrofit installations.

  3. Attitude Control Subsystem for the Advanced Communications Technology Satellite

    Science.gov (United States)

    Hewston, Alan W.; Mitchell, Kent A.; Sawicki, Jerzy T.

    1996-01-01

    This paper provides an overview of the on-orbit operation of the Attitude Control Subsystem (ACS) for the Advanced Communications Technology Satellite (ACTS). The three ACTS control axes are defined, including the means for sensing attitude and determining the pointing errors. The desired pointing requirements for various modes of control as well as the disturbance torques that oppose the control are identified. Finally, the hardware actuators and control loops utilized to reduce the attitude error are described.

  4. Radioisotope thermoelectric generator transportation system subsystem 143 software development plan

    International Nuclear Information System (INIS)

    King, D.A.

    1994-01-01

    This plan describes the activities to be performed and the controls to be applied to the process of specifying, developing, and qualifying the data acquisition software for the Radioisotope Thermoelectric Generator (RTG) Transportation System Subsystem 143 Instrumentation and Data Acquisition System (IDAS). This plan will serve as a software quality assurance plan, a verification and validation (V and V) plan, and a configuration management plan

  5. FireSignal application Node for subsystem control

    International Nuclear Information System (INIS)

    Duarte, A.S.; Santos, B.; Pereira, T.; Carvalho, B.B.; Fernandes, H.; Neto, A.; Janky, F.; Cahyna, P.; Pisacka, J.; Hron, M.

    2010-01-01

    Modern fusion experiments require the presence of several subsystems, responsible for the different parameters involved in the operation of the machine. With the migration from the pre-programmed to the real-time control paradigm, their integration in Control, Data Acquisition, and Communication (CODAC) systems became an important issue, as this implies not only the connection to a main central coordination system, but also communications with related diagnostics and actuators. A subsystem for the control and operation of the vacuum, gas injection and baking was developed and installed in the COMPASS tokamak. These tasks are performed by dsPIC microcontrollers that receive commands from a hub computer and send information regarding the status of the operation. Communications are done in the serial protocol RS-232 through fibre optics. Java software, with an intuitive graphical user interface, for controlling and monitoring of the subsystem was developed and installed in a hub computer. In order to allow operators to perform these tasks remotely besides locally, this was integrated in the FireSignal system. Taking advantage of FireSignal features, it was possible to provide the users with, not only the same functionalities of the local application but also a similar user interface. An independent FireSignal Java Node bridges the central server and the control application. This design makes possible to easily reuse the Node for other subsystems or integrate the vacuum slow control in the other CODAC systems. The complete system, with local and remote control, has been installed successfully on COMPASS and has been in operation since April this year.

  6. Frozen density embedding with non-integer subsystems' particle numbers.

    Science.gov (United States)

    Fabiano, Eduardo; Laricchia, Savio; Della Sala, Fabio

    2014-03-21

    We extend the frozen density embedding theory to non-integer subsystems' particles numbers. Different features of this formulation are discussed, with special concern for approximate embedding calculations. In particular, we highlight the relation between the non-integer particle-number partition scheme and the resulting embedding errors. Finally, we provide a discussion of the implications of the present theory for the derivative discontinuity issue and the calculation of chemical reactivity descriptors.

  7. Stability of subsystem solutions in agent-based models

    Science.gov (United States)

    Perc, Matjaž

    2018-01-01

    The fact that relatively simple entities, such as particles or neurons, or even ants or bees or humans, give rise to fascinatingly complex behaviour when interacting in large numbers is the hallmark of complex systems science. Agent-based models are frequently employed for modelling and obtaining a predictive understanding of complex systems. Since the sheer number of equations that describe the behaviour of an entire agent-based model often makes it impossible to solve such models exactly, Monte Carlo simulation methods must be used for the analysis. However, unlike pairwise interactions among particles that typically govern solid-state physics systems, interactions among agents that describe systems in biology, sociology or the humanities often involve group interactions, and they also involve a larger number of possible states even for the most simplified description of reality. This begets the question: when can we be certain that an observed simulation outcome of an agent-based model is actually stable and valid in the large system-size limit? The latter is key for the correct determination of phase transitions between different stable solutions, and for the understanding of the underlying microscopic processes that led to these phase transitions. We show that a satisfactory answer can only be obtained by means of a complete stability analysis of subsystem solutions. A subsystem solution can be formed by any subset of all possible agent states. The winner between two subsystem solutions can be determined by the average moving direction of the invasion front that separates them, yet it is crucial that the competing subsystem solutions are characterised by a proper composition and spatiotemporal structure before the competition starts. We use the spatial public goods game with diverse tolerance as an example, but the approach has relevance for a wide variety of agent-based models.

  8. Subsystem for control of isotope production with linear electron accelerator

    International Nuclear Information System (INIS)

    Karasyov, S.P.; Pomatsalyuk, R.I.; Uvarov, V.L.

    2001-01-01

    In this report the high-current LINAC subsystem for diagnostic and monitoring the basic technological parameters of isotope production (energy flux of Bremsstrahlung photons and absorbed doze in the target,target activity, temperature and consumption of water cooling the converter and target) is described.T he parallel printer port (LPT) of the personal computer is proposed to use as an interface with the measurement channels

  9. Functional Analysis for Double Shell Tank (DST) Subsystems

    International Nuclear Information System (INIS)

    SMITH, D.F.

    2000-01-01

    This functional analysis identifies the hierarchy and describes the subsystem functions that support the Double-Shell Tank (DST) System described in HNF-SD-WM-TRD-007, System Specification for the Double-Shell Tank System. Because of the uncertainty associated with the need for upgrades of the existing catch tanks supporting the Waste Feed Delivery (WFD) mission, catch tank functions are not addressed in this document. The functions identified herein are applicable to the Phase 1 WFD mission only

  10. FireSignal Application Node for Subsystem Control

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, A.; Santos, B.; Pereira, T.; Carvalho, B.; Fernandes, H. [Instituto de Plasmas e Fusao Nuclear - Instituto Superior Tecnico, Lisbon (Portugal); Cahyna, P.; Pisacka, J.; Hron, M. [Institute of Plasma Physics AS CR, Association EURATOM/IPP.CR, Prague (Czech Republic)

    2009-07-01

    Modern fusion experiments require the presence of several sub-systems, responsible for the different parameters involved in the operation of the machine. With the migration from the pre-programmed to the real-time control paradigm, their integration in Control, Data Acquisition, and Communication (CODAC) systems became an important issue, as this implies not only the connection to a main central coordination system, but also communications with related diagnostics and actuators. A sub-system for the control and operation of the vacuum, gas injection and baking was developed and installed in the COMPASS tokamak. These tasks are performed by 'dsPIC' micro-controllers that receive commands from a computer and send information regarding the status of the operation. Communications are done in the serial protocol RS-232 through fibre optics at speeds up to 1 Mbaud. A Java software, with an intuitive graphical user interface, for controlling and monitoring the sub-system was developed and installed in a hub computer. In order to allow operators to perform these tasks remotely besides locally, this was integrated in the FireSignal system. Taking advantage of FireSignal features, it was possible to provide the users with, not only the same functionalities of the local application but also a similar user interface. An independent FireSignal Java node bridges the central server and the control application. This design makes possible to easily reuse the node for other subsystems or integrate the vacuum slow control in the other CODAC systems. This document is composed of an abstract and a poster. (authors)

  11. Design of nanophotonic circuits for autonomous subsystem quantum error correction

    Energy Technology Data Exchange (ETDEWEB)

    Kerckhoff, J; Pavlichin, D S; Chalabi, H; Mabuchi, H, E-mail: jkerc@stanford.edu [Edward L Ginzton Laboratory, Stanford University, Stanford, CA 94305 (United States)

    2011-05-15

    We reapply our approach to designing nanophotonic quantum memories in order to formulate an optical network that autonomously protects a single logical qubit against arbitrary single-qubit errors. Emulating the nine-qubit Bacon-Shor subsystem code, the network replaces the traditionally discrete syndrome measurement and correction steps by continuous, time-independent optical interactions and coherent feedback of unitarily processed optical fields.

  12. SING-dialoque subsystem for graphical representation of one-dimensional array contents

    International Nuclear Information System (INIS)

    Karlov, A.A.; Kirilov, A.S.

    1979-01-01

    General principles of organization and main features of dialogue subsystem for graphical representation of one-dimensional array contents are considered. The subsystem is developed for remote display station of the JINR BESM-6 computer. Some examples of using the subsystem for drawing curves and histograms are given. The subsystem is developed according to modern dialogue systems requirements. It is ''open'' for extension and could be installed into other computers [ru

  13. Static Feed Water Electrolysis Subsystem Testing and Component Development

    Science.gov (United States)

    Koszenski, E. P.; Schubert, F. H.; Burke, K. A.

    1983-01-01

    A program was carried out to develop and test advanced electrochemical cells/modules and critical electromechanical components for a static feed (alkaline electrolyte) water electrolysis oxygen generation subsystem. The accomplishments were refurbishment of a previously developed subsystem and successful demonstration for a total of 2980 hours of normal operation; achievement of sustained one-person level oxygen generation performance with state-of-the-art cell voltages averaging 1.61 V at 191 ASF for an operating temperature of 128F (equivalent to 1.51V when normalized to 180F); endurance testing and demonstration of reliable performance of the three-fluid pressure controller for 8650 hours; design and development of a fluid control assembly for this subsystem and demonstration of its performance; development and demonstration at the single cell and module levels of a unitized core composite cell that provides expanded differential pressure tolerance capability; fabrication and evaluation of a feed water electrolyte elimination five-cell module; and successful demonstration of an electrolysis module pressurization technique that can be used in place of nitrogen gas during the standby mode of operation to maintain system pressure and differential pressures.

  14. Quantitative risk analysis of a space shuttle subsystem

    International Nuclear Information System (INIS)

    Frank, M.V.

    1989-01-01

    This paper reports that in an attempt to investigate methods for risk management other than qualitative analysis techniques, NASA has funded pilot study quantitative risk analyses for space shuttle subsystems. The authors performed one such study of two shuttle subsystems with McDonnell Douglas Astronautics Company. The subsystems were the auxiliary power units (APU) on the orbiter, and the hydraulic power units on the solid rocket booster. The technology and results of the APU study are presented in this paper. Drawing from a rich in-flight database as well as from a wealth of tests and analyses, the study quantitatively assessed the risk of APU-initiated scenarios on the shuttle during all phases of a flight mission. Damage states of interest were loss of crew/vehicle, aborted mission, and launch scrub. A quantitative risk analysis approach to deciding on important items for risk management was contrasted with the current NASA failure mode and effects analysis/critical item list approach

  15. Double Shell Tank (DST) Transfer Pump Subsystem Specification

    International Nuclear Information System (INIS)

    LESHIKAR, G.A.

    2000-01-01

    This specification establishes the performance requirements and provides references to the requisite codes and standards to be applied to the Double-Shell Tank (DST) Transfer Pump Subsystem which supports the first phase of Waste Feed Delivery (WFD). This specification establishes the performance requirements and provides the references to the requisite codes and standards to be applied during the design of the DST Transfer Pump Subsystem that supports the first phase of (WFD). The DST Transfer Pump Subsystem consists of a pump for supernatant and or slurry transfer for the DSTs that will be retrieved during the Phase 1 WFD operations. This system is used to transfer low-activity waste (LAW) and high-level waste (HLW) to designated DST staging tanks. It also will deliver blended LAW and HLW feed from these staging tanks to the River Protection Project (RPP) Privatization Contractor facility where it will be processed into an immobilized waste form. This specification is intended to be the basis for new projects/installations (W-521, etc.). This specification is not intended to retroactively affect previously established project design criteria without specific direction by the program

  16. Predicting Speech Intelligibility with a Multiple Speech Subsystems Approach in Children with Cerebral Palsy

    Science.gov (United States)

    Lee, Jimin; Hustad, Katherine C.; Weismer, Gary

    2014-01-01

    Purpose: Speech acoustic characteristics of children with cerebral palsy (CP) were examined with a multiple speech subsystems approach; speech intelligibility was evaluated using a prediction model in which acoustic measures were selected to represent three speech subsystems. Method: Nine acoustic variables reflecting different subsystems, and…

  17. 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.

  18. Fiscal 1974 research report. General research on hydrogen energy subsystems; 1974 nendo suiso riyo subsystem sogoteki kento hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1975-03-01

    Based on the contract research 'General research on hydrogen energy subsystems and their peripheral technologies' with Agency of Industrial Science and Technology, each of 7 organizations including Denki Kagaku Kyokai (Electrochemical Association) promoted the research on hydrogen energy subsystem, combustion, fuel cell, car engine, aircraft engine, gas turbine and chemical energy, respectively. This report summarizes the research result on the former of 2 committees on hydrogen energy and peripheral technologies promoted by Denki Kagaku Kyokai. The first part describes the merit, demerit, domestic and overseas R and D states, technical problems, and future research issue for every use form of hydrogen. This part also outlines the short-, medium- and long-term prospects for use of hydrogen and oxygen energy, and describes the whole future research issue. The second part summarizes the content of each committee report. Although on details the original reports of each committee should be lead, this report is useful for obtaining the outline of utilization of hydrogen energy. (NEDO)

  19. On DESTINY Science Instrument Electrical and Electronics Subsystem Framework

    Science.gov (United States)

    Kizhner, Semion; Benford, Dominic J.; Lauer, Tod R.

    2009-01-01

    Future space missions are going to require large focal planes with many sensing arrays and hundreds of millions of pixels all read out at high data rates'' . This will place unique demands on the electrical and electronics (EE) subsystem design and it will be critically important to have high technology readiness level (TRL) EE concepts ready to support such missions. One such omission is the Joint Dark Energy Mission (JDEM) charged with making precise measurements of the expansion rate of the universe to reveal vital clues about the nature of dark energy - a hypothetical form of energy that permeates all of space and tends to increase the rate of the expansion. One of three JDEM concept studies - the Dark Energy Space Telescope (DESTINY) was conducted in 2008 at the NASA's Goddard Space Flight Center (GSFC) in Greenbelt, Maryland. This paper presents the EE subsystem framework, which evolved from the DESTINY science instrument study. It describes the main challenges and implementation concepts related to the design of an EE subsystem featuring multiple focal planes populated with dozens of large arrays and millions of pixels. The focal planes are passively cooled to cryogenic temperatures (below 140 K). The sensor mosaic is controlled by a large number of Readout Integrated Circuits and Application Specific Integrated Circuits - the ROICs/ASICs in near proximity to their sensor focal planes. The ASICs, in turn, are serviced by a set of "warm" EE subsystem boxes performing Field Programmable Gate Array (FPGA) based digital signal processing (DSP) computations of complex algorithms, such as sampling-up-the-ramp algorithm (SUTR), over large volumes of fast data streams. The SUTR boxes are supported by the Instrument Control/Command and Data Handling box (ICDH Primary and Backup boxes) for lossless data compression, command and low volume telemetry handling, power conversion and for communications with the spacecraft. The paper outlines how the JDEM DESTINY concept

  20. NASA program planning on nuclear electric propulsion

    International Nuclear Information System (INIS)

    Bennett, G.L.; Miller, T.J.

    1992-03-01

    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. 28 refs

  1. Fitting aerodynamics and propulsion into the puzzle

    Science.gov (United States)

    Johnston, Patrick J.; Whitehead, Allen H., Jr.; Chapman, Gary T.

    1987-01-01

    The development of an airbreathing single-stage-to-orbit vehicle, in particular the problems of aerodynamics and propulsion integration, is examined. The boundary layer transition on constant pressure surfaces at hypersonic velocities, and the effects of noise on the transition are investigated. The importance of viscosity, real-gas effects, and drag at hypersonic speeds is discussed. A propulsion system with sufficient propulsive lift to enhance the performance of the vehicle is being developed. The difficulties of engine-airframe integration are analyzed.

  2. 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,

  3. National Ignition Facility, subsystem design requirements beam control and laser diagnostics SSDR 1.7

    International Nuclear Information System (INIS)

    Bliss, E.

    1996-01-01

    This Subsystem Design Requirement document is a development specification that establishes the performance, design, development, and test requirements for the Alignment subsystem (WBS 1.7.1), Beam Diagnostics (WBS 1.7.2), and the Wavefront Control subsystem (WBS 1.7. 3) of the NIF Laser System (WBS 1.3). These three subsystems are collectively referred to as the Beam Control ampersand Laser Diagnostics Subsystem. The NIF is a multi-pass, 192-beam, high-power, neodymium-glass laser that meets requirements set forth in the NIF SDR 002 (Laser System). 3 figs., 3 tabs

  4. Autonomous navigation - The ARMMS concept. [Autonomous Redundancy and Maintenance Management Subsystem

    Science.gov (United States)

    Wood, L. J.; Jones, J. B.; Mease, K. D.; Kwok, J. H.; Goltz, G. L.; Kechichian, J. A.

    1984-01-01

    A conceptual design is outlined for the navigation subsystem of the Autonomous Redundancy and Maintenance Management Subsystem (ARMMS). The principal function of this navigation subsystem is to maintain the spacecraft over a specified equatorial longitude to within + or - 3 deg. In addition, the navigation subsystem must detect and correct internal faults. It comprises elements for a navigation executive and for orbit determination, trajectory, maneuver planning, and maneuver command. Each of these elements is described. The navigation subsystem is to be used in the DSCS III spacecraft.

  5. Systems and methods for an integrated electrical sub-system powered by wind energy

    Science.gov (United States)

    Liu, Yan [Ballston Lake, NY; Garces, Luis Jose [Niskayuna, NY

    2008-06-24

    Various embodiments relate to systems and methods related to an integrated electrically-powered sub-system and wind power system including a wind power source, an electrically-powered sub-system coupled to and at least partially powered by the wind power source, the electrically-powered sub-system being coupled to the wind power source through power converters, and a supervisory controller coupled to the wind power source and the electrically-powered sub-system to monitor and manage the integrated electrically-powered sub-system and wind power system.

  6. 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.

  7. Reusable Orbit Transfer Vehicle Propulsion Technology Considerations

    National Research Council Canada - National Science Library

    Perkins, Dave

    1998-01-01

    .... ROTV propulsion technologies to consider chemical rockets have limited mission capture, solar thermal rockets capture most missions but LH2 issues, and electric has highest PL without volume constraint...

  8. 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.

  9. Magnetic propulsion for magnetically levitated trains

    Energy Technology Data Exchange (ETDEWEB)

    Melville, P H

    1973-12-01

    One of the main problems associated with magnetically levitated trains is the means of propulsion. A system is described whereby the repulsion from the superconducting magnets, in addition to levitating the train, can also be used to propel it.

  10. 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...

  11. 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...

  12. 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...

  13. 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

    Nuclear Thermal Propulsion (NTP) is a concept which uses a nuclear reactor to heat a propellant to high temperatures without combustion and can achieve significantly greater specific impulse than chemical engines. NTP has been considered many times for human and cargo missions beyond low earth orbit. A lot of development and technical maturation of NTP components took place during the Rover/NERVA program of the 60's and early 70's. Other NTP programs and studies followed attempting to further mature the NTP concept and identify a champion customer willing to devote the funds and support the development schedule to a demonstration mission. Budgetary constraints require the use of an affordable development and qualification strategy that takes into account all the previous work performed on NTP to construct an existing database, and include lessons learned and past guidelines followed. Current guidelines and standards NASA uses for human rating chemical rocket engines is referenced. The long lead items for NTP development involve the fuel elements of the reactor and ground testing the engine system, subsystem, and components. Other considerations which greatly impact the development plans includes the National Space Policy, National Environmental Policy Act, Presidential Directive/National Security Council Memorandum #25 (Scientific or Technological Experiments with Possible Large-Scale Adverse Environmental Effects and Launch of Nuclear Systems into Space), and Safeguards and Security. Ground testing will utilize non-nuclear test capabilities to help down select components and subsystems before testing in a nuclear environment to save time and cost. Existing test facilities with minor modifications will be considered to the maximum extent practical. New facilities will be designed to meet minimum requirements. Engine and test facility requirements are based on the driving mission requirements with added factors of safety for better assurance and reliability

  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. Solar electric propulsion for Mars transport vehicles

    Science.gov (United States)

    Hickman, J. M.; Curtis, H. B.; Alexander, S. W.; Gilland, J. H.; Hack, K. J.; Lawrence, C.; Swartz, C. K.

    1990-01-01

    Solar electric propulsion (SEP) is an alternative to chemical and nuclear powered propulsion systems for both piloted and unpiloted Mars transport vehicles. Photovoltaic solar cell and array technologies were evaluated as components of SEP power systems. Of the systems considered, the SEP power system composed of multijunction solar cells in an ENTECH domed fresnel concentrator array had the least array mass and area. Trip times to Mars optimized for minimum propellant mass were calculated. Additionally, a preliminary vehicle concept was designed.

  16. Institute for Computational Mechanics in Propulsion (ICOMP)

    Science.gov (United States)

    Keith, Theo G., Jr. (Editor); Balog, Karen (Editor); Povinelli, Louis A. (Editor)

    2001-01-01

    The Institute for Computational Mechanics in Propulsion (ICOMP) was formed to develop techniques to improve problem-solving capabilities in all aspects of computational mechanics related to propulsion. ICOMP is operated by the Ohio Aerospace Institute (OAI) and funded via numerous cooperative agreements by the NASA Glenn Research Center in Cleveland, Ohio. This report describes the activities at ICOMP during 1999, the Institute's fourteenth year of operation.

  17. 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.

  18. Passive propulsion in vortex wakes

    Science.gov (United States)

    Beal, D. N.; Hover, F. S.; Triantafyllou, M. S.; Liao, J. C.; Lauder, G. V.

    A dead fish is propelled upstream when its flexible body resonates with oncoming vortices formed in the wake of a bluff cylinder, despite being well outside the suction region of the cylinder. Within this passive propulsion mode, the body of the fish extracts sufficient energy from the oncoming vortices to develop thrust to overcome its own drag. In a similar turbulent wake and at roughly the same distance behind a bluff cylinder, a passively mounted high-aspect-ratio foil is also shown to propel itself upstream employing a similar flow energy extraction mechanism. In this case, mechanical energy is extracted from the flow at the same time that thrust is produced. These results prove experimentally that, under proper conditions, a body can follow at a distance or even catch up to another upstream body without expending any energy of its own. This observation is also significant in the development of low-drag energy harvesting devices, and in the energetics of fish dwelling in flowing water and swimming behind wake-forming obstacles.

  19. Development of the CsI Calorimeter Subsystem for AMEGO

    Science.gov (United States)

    Grove, J. Eric; Woolf, Richard; Johnson, W. Neil; Phlips, Bernard

    2018-01-01

    We report on the development of the thallium-doped cesium iodide (CsI:Tl) calorimeter subsystem for the All-Sky Medium-Energy Gamma-ray Observatory (AMEGO). The CsI calorimeter is one of the three main subsystems that comprise the AMEGO instrument suite; the others include the double-sided silicon strip detector (DSSD) tracker/converter and a cadmium zinc telluride (CZT) calorimeter. Similar to the LAT instrument on Fermi, the hodoscopic calorimeter consists of orthogonally layered CsI bars. Unlike the LAT, which uses PIN photodiodes, the scintillation light readout from each end of the CsI bar is done with recently developed large-area silicon photomultiplier (SiPM) arrays. We currently have an APRA program to develop the calorimeter technology for a larger, future space-based gamma-ray observatory. Under this program, we are building and testing a prototype calorimeter consisting of 24 CsI bars (16.7 mm x 16.7 mm x 100 mm) arranged in 4 layers with 6 bars per layer. The ends of each bar are read out with a 2 x 2 array of 6 mm x 6 mm SensL J series SiPMs. Signal readout and processing is done with the IDEAS SIPHRA (IDE3380) ASIC. Performance testing of this prototype will be done with laboratory sources, a beam test, and a balloon flight in conjunction with the other subsystems led by NASA GSFC. Additionally, we will test 16.7 mm x 16.7 mm x 450 mm CsI bars with SiPM readout to understand the performance of longer bars in advance of the developing the full instrument.Acknowledgement: This work was sponsored by the Chief of Naval Research (CNR) and NASA-APRA (NNH15ZDA001N-APRA).

  20. RF communications subsystem for the Radiation Belt Storm Probes mission

    Science.gov (United States)

    Srinivasan, Dipak K.; Artis, David; Baker, Ben; Stilwell, Robert; Wallis, Robert

    2009-12-01

    The NASA Radiation Belt Storm Probes (RBSP) mission, currently in Phase B, is a two-spacecraft, Earth-orbiting mission, which will launch in 2012. The spacecraft's S-band radio frequency (RF) telecommunications subsystem has three primary functions: provide spacecraft command capability, provide spacecraft telemetry and science data return, and provide accurate Doppler data for navigation. The primary communications link to the ground is via the Johns Hopkins University Applied Physics Laboratory's (JHU/APL) 18 m dish, with secondary links to the NASA 13 m Ground Network and the Tracking and Data Relay Spacecraft System (TDRSS) in single-access mode. The on-board RF subsystem features the APL-built coherent transceiver and in-house builds of a solid-state power amplifier and conical bifilar helix broad-beam antennas. The coherent transceiver provides coherency digitally, and controls the downlink data rate and encoding within its field-programmable gate array (FPGA). The transceiver also provides a critical command decoder (CCD) function, which is used to protect against box-level upsets in the C&DH subsystem. Because RBSP is a spin-stabilized mission, the antennas must be symmetric about the spin axis. Two broad-beam antennas point along both ends of the spin axis, providing communication coverage from boresight to 70°. An RF splitter excites both antennas; therefore, the mission is designed such that no communications are required close to 90° from the spin axis due to the interferometer effect from the two antennas. To maximize the total downlink volume from the spacecraft, the CCSDS File Delivery Protocol (CFDP) has been baselined for the RBSP mission. During real-time ground contacts with the APL ground station, downlinked files are checked for errors. Handshaking between flight and ground CFDP software results in requests to retransmit only the file fragments lost due to dropouts. This allows minimization of RF link margins, thereby maximizing data rate and

  1. Electric and hybrid vehicles environmental control subsystem study

    Science.gov (United States)

    1981-01-01

    An environmental control subsystem (ECS) in the passenger compartment of electric and hybrid vehicles is studied. Various methods of obtaining the desired temperature control for the battery pack is also studied. The functional requirements of ECS equipment is defined. Following categorization by methodology, technology availability and risk, all viable ECS concepts are evaluated. Each is assessed independently for benefits versus risk, as well as for its feasibility to short, intermediate and long term product development. Selection of the preferred concept is made against these requirements, as well as the study's major goal of providing safe, highly efficient and thermally confortable ECS equipment.

  2. The New York Public Library Automated Book Catalog Subsystem

    Directory of Open Access Journals (Sweden)

    S. Michael Malinconico

    1973-03-01

    Full Text Available A comprehensive automated bibliographic control system has been developed by the New York Public Library. This system is unique in its use of an automated authority system and highly sophisticated machine filing algorithms. The primary aim was the rigorous control of established forms and their cross-reference structure. The original impetus for creation of the system, and its most highly visible product, is a photocomposed book catalog. The book catalog subsystem supplies automatic punctuation of condensed entries and contains the ability to pmduce cumulation/ supplement book catalogs in installments without loss of control of the crossreferencing structure.

  3. Recent developments for the Large Binocular Telescope Guiding Control Subsystem

    Science.gov (United States)

    Golota, T.; De La Peña, M. D.; Biddick, C.; Lesser, M.; Leibold, T.; Miller, D.; Meeks, R.; Hahn, T.; Storm, J.; Sargent, T.; Summers, D.; Hill, J.; Kraus, J.; Hooper, S.; Fisher, D.

    2014-07-01

    The Large Binocular Telescope (LBT) has eight Acquisition, Guiding, and wavefront Sensing Units (AGw units). They provide guiding and wavefront sensing capability at eight different locations at both direct and bent Gregorian focal stations. Recent additions of focal stations for PEPSI and MODS instruments doubled the number of focal stations in use including respective motion, camera controller server computers, and software infrastructure communicating with Guiding Control Subsystem (GCS). This paper describes the improvements made to the LBT GCS and explains how these changes have led to better maintainability and contributed to increased reliability. This paper also discusses the current GCS status and reviews potential upgrades to further improve its performance.

  4. Architecture of the software for LAMOST fiber positioning subsystem

    Science.gov (United States)

    Peng, Xiaobo; Xing, Xiaozheng; Hu, Hongzhuan; Zhai, Chao; Li, Weimin

    2004-09-01

    The architecture of the software which controls the LAMOST fiber positioning sub-system is described. The software is composed of two parts as follows: a main control program in a computer and a unit controller program in a MCS51 single chip microcomputer ROM. And the function of the software includes: Client/Server model establishment, observation planning, collision handling, data transmission, pulse generation, CCD control, image capture and processing, and data analysis etc. Particular attention is paid to the ways in which different parts of the software can communicate. Also software techniques for multi threads, SOCKET programming, Microsoft Windows message response, and serial communications are discussed.

  5. Analysis of subsystems in wavelength-division-multiplexing networks

    DEFF Research Database (Denmark)

    Liu, Fenghai

    2001-01-01

    Wavelength division multiplexing (WDM) technology together with optical amplification has created a new era for optical communication. Transmission capacity is greatly increased by adding more and more wavelength channels into a single fiber, as well as by increasing the line rate of each channel...... in semiconductor optical amplifiers (SOAs), and dispersion managed fiber sections. New subsystems are also proposed in the thesis: a modular 2×2 multiwavelength cross-connect using wavelength switching blocks, a wavelength converter based on cross phase modulation in a semiconductor modulator, a wavelength...

  6. Information measuring subsystem oil pumping station “Parabel”

    Directory of Open Access Journals (Sweden)

    Nyashina Galina S.

    2014-01-01

    Full Text Available Information-measurement subsystem oil pumping station (OPS “Parabel”, located on the site of the main pipeline “Alexandrov-Anzhero” (OJSC “AK” Transneft "”. Developed on the basis of a modern microprocessor equipment, automation, as well as high-speed digital data channels. The simple solution to meet the requirements set out in the guidance document "Automation and remote control of trunk pipelines. «General provisions» (RD-35.240.0000-KTN-207-08.

  7. Reactor Subsystem Simulation for Nuclear Hybrid Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Shannon Bragg-Sitton; J. Michael Doster; Alan Rominger

    2012-09-01

    Preliminary system models have been developed by Idaho National Laboratory researchers and are currently being enhanced to assess integrated system performance given multiple sources (e.g., nuclear + wind) and multiple applications (i.e., electricity + process heat). Initial efforts to integrate a Fortran-based simulation of a small modular reactor (SMR) with the balance of plant model have been completed in FY12. This initial effort takes advantage of an existing SMR model developed at North Carolina State University to provide initial integrated system simulation for a relatively low cost. The SMR subsystem simulation details are discussed in this report.

  8. Data Management Applications for the Service Preparation Subsystem

    Science.gov (United States)

    Luong, Ivy P.; Chang, George W.; Bui, Tung; Allen, Christopher; Malhotra, Shantanu; Chen, Fannie C.; Bui, Bach X.; Gutheinz, Sandy C.; Kim, Rachel Y.; Zendejas, Silvino C.; hide

    2009-01-01

    These software applications provide intuitive User Interfaces (UIs) with a consistent look and feel for interaction with, and control of, the Service Preparation Subsystem (SPS). The elements of the UIs described here are the File Manager, Mission Manager, and Log Monitor applications. All UIs provide access to add/delete/update data entities in a complex database schema without requiring technical expertise on the part of the end users. These applications allow for safe, validated, catalogued input of data. Also, the software has been designed in multiple, coherent layers to promote ease of code maintenance and reuse in addition to reducing testing and accelerating maturity.

  9. Low Current Surface Flashover for Initiation of Electric Propulsion Devices

    Science.gov (United States)

    Dary, Omar G.

    There has been a recent increase in interest in miniaturization of propulsion systems for satellites. These systems are needed to propel micro- and nano-satellites, where platforms are much smaller than conventional satellites and require smaller levels of thrust. Micro-propulsion systems for these satellites are in their infancy and they must manage with smaller power systems and smaller propellant volumes. Electric propulsion systems operating on various types of electric discharges are typically used for these needs. One of the central components of such electrical micropropulsion systems are ignitor subsystems, which are required for creation the breakdown and initiation of the main discharge. Ignitors have to provide reliable ignition for entire lifetime of the micropropulsion system. Electric breakdown in vacuum usually require high voltage potentials of hundreds of kilovolts per mm to induce breakdown. The breakdown voltage can be significantly decreased (down to several kVs per mm) if dielectric surface flashover is utilized. However, classical dielectric surface flashover operates at large electric current (100s of Amperes) and associated with overheating and damage of the electrodes/dielectric assembly after several flashover events. The central idea of this work was to eliminate the damage to the flashover electrode assembly by limiting the flashover currents to low values in milliampere range (Low Current Surface Flashover -LCSF) and utilize LCSF system as an ignition source for the main discharge on the micropropulsion system. The main objective of this research was to create a robust LCSF ignition system, capable producing a large number of surface flashover triggering events without significant damage to the LCSF electrode assembly. The thesis aims to characterize the plasma plume created at LCSF, study electrodes ablation and identify conditions required for robust triggering of main discharge utilized on micro-propulsion system. Conditioning of a

  10. Status and Perspectives of Electric Propulsion in Italy

    Science.gov (United States)

    Svelto, F.; Marcuccio, S.; Matticari, G.

    2002-01-01

    Electric Propulsion (EP) is recognized as one of today's enabling technologies for scientific and commercial missions. In consideration of EP's major strategic impact on the near and long term scenarios, an EP development programme has been established within the Italian Space Agency (ASI), aimed at the development of a variety of propulsion capabilities covering different fields of application. This paper presents an overview of Electric Propulsion (EP) activities underway in Italy and outlines the planned development lines, both in research institutions and in industry. Italian EP activities are essentially concentrated in Pisa, at Centrospazio and Alta, and in Florence, at LABEN - Proel Tecnologie Division (LABEN/Proel). Centrospazio/Alta and LABEN/Proel have established a collaboration program for joint advanced developments in the EP field. Established in 1989, Centrospazio is a private research center closely related to the Department of Aerospace Engineering of Pisa University. Along the years, Centrospazio lines of development have included arcjets, magneto- plasma-dynamic thrusters, FEEP and Hall thrusters, as well as computational plasma dynamics and low-thrust mission studies. Alta, a small enterprise, was founded in 1999 to exploit in an industrial setting the results of research previously carried out at Centrospazio. Alta's activities include the development of micronewton and millinewton FEEP thrusters, and testing of high power Hall and ion thrusters in specialised facilities. A full micronewton FEEP propulsion system is being developed for the Microscope spacecraft, a scientific mission by CNES aimed at verification of the Equivalence Principle. FEEP will also fly on ASI's HypSEO, a technological demonstrator for Earth Observation, and is being considered for ESA's GOCE (geodesy) and SMART-2 (formation flying), as well as for the intended scientific spacecraft GG by ASI. The ASI-funded STEPS facility will be placed on an external site on the

  11. The Ion Propulsion System for the Solar Electric Propulsion Technology Demonstration Mission

    Science.gov (United States)

    Herman, Daniel A.; Santiago, Walter; Kamhawi, Hani; Polk, James E.; Snyder, John Steven; Hofer, Richard R.; Parker, J. Morgan

    2015-01-01

    The Asteroid Redirect Robotic Mission is a candidate Solar Electric Propulsion Technology Demonstration Mission whose main objectives are to develop and demonstrate a high-power solar electric propulsion capability for the Agency and return an asteroidal mass for rendezvous and characterization in a companion human-crewed mission. The ion propulsion system must be capable of operating over an 8-year time period and processing up to 10,000 kg of xenon propellant. This high-power solar electric propulsion capability, or an extensible derivative of it, has been identified as a critical part of an affordable, beyond-low-Earth-orbit, manned-exploration architecture. Under the NASA Space Technology Mission Directorate the critical electric propulsion and solar array technologies are being developed. The ion propulsion system being co-developed by the NASA Glenn Research Center and the Jet Propulsion Laboratory for the Asteroid Redirect Vehicle is based on the NASA-developed 12.5 kW Hall Effect Rocket with Magnetic Shielding (HERMeS0 thruster and power processing technologies. This paper presents the conceptual design for the ion propulsion system, the status of the NASA in-house thruster and power processing activity, and an update on flight hardware.

  12. Optimum cycle frequencies in hand-rim wheelchair propulsion. Wheelchair propulsion technique

    NARCIS (Netherlands)

    van der Woude, L H; Veeger, DirkJan (H. E. J.); Rozendal, R H; Sargeant, A J

    1989-01-01

    To study the effect of different cycle frequencies on cardio-respiratory responses and propulsion technique in hand-rim wheelchair propulsion, experienced wheelchair sportsmen (WS group; n = 6) and non-wheelchair users (NW group; n = 6) performed wheelchair exercise tests on a motor-driven

  13. Effect of workload setting on propulsion technique in handrim wheelchair propulsion

    NARCIS (Netherlands)

    van Drongelen, Stefan; Arnet, Ursina; Veeger, DirkJan (H E. J); van der Woude, Lucas H. V.

    Objective: To investigate the influence of workload setting (speed at constant power, method to impose power) on the propulsion technique (i.e. force and timing characteristics) in handrim wheelchair propulsion. Method: Twelve able-bodied men participated in this study. External forces were measured

  14. Coordination and propulsion and non-propulsion phases in 100 meter breaststroke swimming.

    Science.gov (United States)

    Strzała, Marek; Krężałek, Piotr; Kucia-Czyszczoń, Katarzyna; Ostrowski, Andrzej; Stanula, Arkadiusz; Tyka, Anna K; Sagalara, Andrzej

    2014-01-01

    The main purpose of this study was to analyze the coordination, propulsion and non-propulsion phases in the 100 meter breaststroke race. Twenty-seven male swimmers (15.7 ± 1.98 years old) with the total body length (TBL) of 247.0 ± 10.60 [cm] performed an all-out 100 m breaststroke bout. The bouts were recorded with an underwater camera installed on a portable trolley. The swimming kinematic parameters, stroke rate (SR) and stroke length (SL), as well as the coordination indices based on propulsive or non-propulsive movement phases of the arms and legs were distinguished. Swimming speed (V100surface breast) was associated with SL (R = 0.41, p study were measured using partial correlations with controlled age. SL interplayed negatively with the limbs propulsive phase Overlap indicator (R = -0.46, p propulsion Glide indicator. The propulsion in-sweep (AP3) phase of arms and their non-propulsion partial air recovery (ARair) phase interplayed with V100surface breast (R = 0.51, p < 0.05 and 0.48 p < 0.05) respectively, displaying the importance of proper execution of this phase (AP3) and in reducing the resistance recovery phases in consecutive ones.

  15. Revealing electronic open quantum systems with subsystem TDDFT

    Science.gov (United States)

    Krishtal, Alisa; Pavanello, Michele

    2016-03-01

    Open quantum systems (OQSs) are perhaps the most realistic systems one can approach through simulations. In recent years, describing OQSs with Density Functional Theory (DFT) has been a prominent avenue of research with most approaches based on a density matrix partitioning in conjunction with an ad-hoc description of system-bath interactions. We propose a different theoretical approach to OQSs based on partitioning of the electron density. Employing the machinery of subsystem DFT (and its time-dependent extension), we provide a novel way of isolating and analyzing the various terms contributing to the coupling between the system and the surrounding bath. To illustrate the theory, we provide numerical simulations on a toy system (a molecular dimer) and on a condensed phase system (solvated excimer). The simulations show that non-Markovian dynamics in the electronic system-bath interactions are important in chemical applications. For instance, we show that the superexchange mechanism of transport in donor-bridge-acceptor systems is a non-Markovian interaction between the donor-acceptor (OQS) with the bridge (bath) which is fully characterized by real-time subsystem time-dependent DFT.

  16. Lunar Advanced Volatile Analysis Subsystem: Pressure Transducer Trade Study

    Science.gov (United States)

    Kang, Edward Shinuk

    2017-01-01

    In Situ Resource Utilization (ISRU) is a key factor in paving the way for the future of human space exploration. The ability to harvest resources on foreign astronomical objects to produce consumables and propellant offers potential reduction in mission cost and risk. Through previous missions, the existence of water ice at the poles of the moon has been identified, however the feasibility of water extraction for resources remains unanswered. The Resource Prospector (RP) mission is currently in development to provide ground truth, and will enable us to characterize the distribution of water at one of the lunar poles. Regolith & Environment Science and Oxygen & Lunar Volatile Extraction (RESOLVE) is the primary payload on RP that will be used in conjunction with a rover. RESOLVE contains multiple instruments for systematically identifying the presence of water. The main process involves the use of two systems within RESOLVE: the Oxygen Volatile Extraction Node (OVEN) and Lunar Advanced Volatile Analysis (LAVA). Within the LAVA subsystem, there are multiple calculations that depend on accurate pressure readings. One of the most important instances where pressure transducers (PT) are used is for calculating the number of moles in a gas transfer from the OVEN subsystem. As a critical component of the main process, a mixture of custom and commercial off the shelf (COTS) PTs are currently being tested in the expected operating environment to eventually down select an option for integrated testing in the LAVA engineering test unit (ETU).

  17. Principles of control for decoherence-free subsystems.

    Science.gov (United States)

    Cappellaro, P; Hodges, J S; Havel, T F; Cory, D G

    2006-07-28

    Decoherence-free subsystems (DFSs) are a powerful means of protecting quantum information against noise with known symmetry properties. Although Hamiltonians that can implement a universal set of logic gates on DFS encoded qubits without ever leaving the protected subsystem theoretically exist, the natural Hamiltonians that are available in specific implementations do not necessarily have this property. Here we describe some of the principles that can be used in such cases to operate on encoded qubits without losing the protection offered by the DFSs. In particular, we show how dynamical decoupling can be used to control decoherence during the unavoidable excursions outside of the DFS. By means of cumulant expansions, we show how the fidelity of quantum gates implemented by this method on a simple two physical qubit DFS depends on the correlation time of the noise responsible for decoherence. We further show by means of numerical simulations how our previously introduced "strongly modulating pulses" for NMR quantum information processing can permit high-fidelity operations on multiple DFS encoded qubits in practice, provided that the rate at which the system can be modulated is fast compared to the correlation time of the noise. The principles thereby illustrated are expected to be broadly applicable to many implementations of quantum information processors based on DFS encoded qubits.

  18. Revealing electronic open quantum systems with subsystem TDDFT.

    Science.gov (United States)

    Krishtal, Alisa; Pavanello, Michele

    2016-03-28

    Open quantum systems (OQSs) are perhaps the most realistic systems one can approach through simulations. In recent years, describing OQSs with Density Functional Theory (DFT) has been a prominent avenue of research with most approaches based on a density matrix partitioning in conjunction with an ad-hoc description of system-bath interactions. We propose a different theoretical approach to OQSs based on partitioning of the electron density. Employing the machinery of subsystem DFT (and its time-dependent extension), we provide a novel way of isolating and analyzing the various terms contributing to the coupling between the system and the surrounding bath. To illustrate the theory, we provide numerical simulations on a toy system (a molecular dimer) and on a condensed phase system (solvated excimer). The simulations show that non-Markovian dynamics in the electronic system-bath interactions are important in chemical applications. For instance, we show that the superexchange mechanism of transport in donor-bridge-acceptor systems is a non-Markovian interaction between the donor-acceptor (OQS) with the bridge (bath) which is fully characterized by real-time subsystem time-dependent DFT.

  19. Modifications in Wheelchair Propulsion Technique with Speed.

    Science.gov (United States)

    Russell, Ian M; Raina, Shashank; Requejo, Philip S; Wilcox, Rand R; Mulroy, Sara; McNitt-Gray, Jill L

    2015-01-01

    Repetitive loading of the upper limb joints during manual wheelchair (WC) propulsion (WCP) has been identified as 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 WC users with paraplegia modify propulsion mechanics to accommodate expected increases in reaction forces (RFs) generated at the pushrim with self-selected increases in WCP speed. Upper extremity kinematics and pushrim RFs were measured for 40 experienced manual WC 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). Increased propulsion speed was accompanied by increases in RF magnitude (22 of 40, >10 N) and shoulder net joint moment (NJM, 15 of 40, >10 Nm) 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. 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 toward preserving musculoskeletal health of the shoulder and improving health-related quality of life.

  20. The development of the intrinsic functional connectivity of default network subsystems from age 3 to 5.

    Science.gov (United States)

    Xiao, Yaqiong; Zhai, Hongchang; Friederici, Angela D; Jia, Fucang

    2016-03-01

    In recent years, research on human functional brain imaging using resting-state fMRI techniques has been increasingly prevalent. The term "default mode" was proposed to describe a baseline or default state of the brain during rest. Recent studies suggested that the default mode network (DMN) is comprised of two functionally distinct subsystems: a dorsal-medial prefrontal cortex (DMPFC) subsystem involved in self-oriented cognition (i.e., theory of mind) and a medial temporal lobe (MTL) subsystem engaged in memory and scene construction; both subsystems interact with the anterior medial prefrontal cortex (aMPFC) and posterior cingulate (PCC) as the core regions of DMN. The present study explored the development of DMN core regions and these two subsystems in both hemispheres from 3- to 5-year-old children. The analysis of the intrinsic activity showed strong developmental changes in both subsystems, and significant changes were specifically found in MTL subsystem, but not in DMPFC subsystem, implying distinct developmental trajectories for DMN subsystems. We found stronger interactions between the DMPFC and MTL subsystems in 5-year-olds, particularly in the left subsystems that support the development of environmental adaptation and relatively complex mental activities. These results also indicate that there is stronger right hemispheric lateralization at age 3, which then changes as bilateral development gradually increases through to age 5, suggesting in turn the hemispheric dominance in DMN subsystems changing with age. The present results provide primary evidence for the development of DMN subsystems in early life, which might be closely related to the development of social cognition in childhood.

  1. Nuclear electric propulsion: An integral part of NASA's nuclear propulsion project

    International Nuclear Information System (INIS)

    Stone, J.R.

    1992-01-01

    NASA has initiated a technology program to establish the readiness of nuclear propulsion technology for the Space Exploration Initiative (SEI). This program was initiated with a very modest effort identified with nuclear thermal propulsion (NTP); however, nuclear electric propulsion (NEP) is also an integral part of this program and builds upon NASA's Base Research and Technology Program in power and electric propulsion as well as the SP-100 space nuclear power program. Although the Synthesis Group On America's SEI has identified NEP only as an option for cargo missions, recent studies conducted by NASA-Lewis show that NEP offers the potential for early manned Mars missions as well. Lower power NEP is also of current interest for outer planetary robotic missions. Current plans are reviewed for the overall nuclear propulsion project, with emphasis on NEP and those elements of NTP program which have synergism with NEP

  2. Effect of workload setting on propulsion technique in handrim wheelchair propulsion.

    Science.gov (United States)

    van Drongelen, Stefan; Arnet, Ursina; Veeger, Dirkjan H E J; van der Woude, Lucas H V

    2013-03-01

    To investigate the influence of workload setting (speed at constant power, method to impose power) on the propulsion technique (i.e. force and timing characteristics) in handrim wheelchair propulsion. Twelve able-bodied men participated in this study. External forces were measured during handrim wheelchair propulsion on a motor driven treadmill at different velocities and constant power output (to test the forced effect of speed) and at power outputs imposed by incline vs. pulley system (to test the effect of method to impose power). Outcome measures were the force and timing variables of the propulsion technique. FEF and timing variables showed significant differences between the speed conditions when propelling at the same power output (p propulsion technique parameters despite an overall constant power output. Copyright © 2012 IPEM. Published by Elsevier Ltd. All rights reserved.

  3. Comparison of candidate solar array maximum power utilization approaches. [for spacecraft propulsion

    Science.gov (United States)

    Costogue, E. N.; Lindena, S.

    1976-01-01

    A study was made of five potential approaches that can be utilized to detect the maximum power point of a solar array while sustaining operations at or near maximum power and without endangering stability or causing array voltage collapse. The approaches studied included: (1) dynamic impedance comparator, (2) reference array measurement, (3) onset of solar array voltage collapse detection, (4) parallel tracker, and (5) direct measurement. The study analyzed the feasibility and adaptability of these approaches to a future solar electric propulsion (SEP) mission, and, specifically, to a comet rendezvous mission. Such missions presented the most challenging requirements to a spacecraft power subsystem in terms of power management over large solar intensity ranges of 1.0 to 3.5 AU. The dynamic impedance approach was found to have the highest figure of merit, and the reference array approach followed closely behind. The results are applicable to terrestrial solar power systems as well as to other than SEP space missions.

  4. Study to adapt solar electric propulsion to the Pioneer F and G spacecraft

    Science.gov (United States)

    1972-01-01

    The addition of an electric thrust subsystem to the spin-stabilized Pioneer F and G spacecraft to improve performance capability for certain missions is discussed. The evaluation was performed for the Atlas and Titan launch vehicles with Centaur and TE-364-4 stages and for electric thrust stages of 8- and 5-kw with three 30- and five 15-cm thrusters respectively. The combination of a spinning spacecraft with electric propulsion is a concept only recently evaluated and the penalty from spinning over three-axis stabilized is not as significant as might initally be thought. There are major gains in weight, cost, and reliability, the disadvantages being lower data rate during the thrust phase and less efficient pointing. A variety of missions were evaluated from a solar approach mission into 0.14 AU to a flyby mission of Neptune at approximately 30 AU. Performance improvements were present for all missions evaluated.

  5. 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

  6. 28th Joint Propulsion Conference and Exhibit

    International Nuclear Information System (INIS)

    Stone, J.R.; Sovey, J.S.

    1992-07-01

    The National Aeronautics and Space Administration (NASA) has initiated a program to establish the readiness of nuclear electric propulsion (NEP) technology for relatively near-term applications to outer planet robotic science missions with potential future evolution to system for piloted Mars vehicles. This program was initiated in 1991 with a very modest effort identified with nuclear thermal propulsion (NTP); however, NEP is also an integral part of this program and builds upon NASA's Base Research and Technology Program in power and electric propulsion as well as the SP-100 space nuclear power program. The NEP Program will establish the feasibility and practicality of electric propulsion for robotic and piloted solar system exploration. The performance objectives are high specific impulse (200 greater than I(sub sp) greater than 10000 s), high efficiency (over 0.50), and low specific mass. The planning for this program was initially focussed on piloted Mars missions, but has since been redirected to first focus on 100-kW class systems for relatively near-term robotic missions, with possible future evolution to megawatt- and multi-megawatt-class systems applicable to cargo vehicles supporting human missions as well as to the piloted vehicles. This paper reviews current plans and recent progress for the overall nuclear electric propulsion project and closely related activities

  7. NASA's nuclear electric propulsion technology project

    International Nuclear Information System (INIS)

    Stone, J.R.; Sovey, J.S.

    1992-07-01

    The National Aeronautics and Space Administration (NASA) has initiated a program to establish the readiness of nuclear electric propulsion (NEP) technology for relatively near-term applications to outer planet robotic science missions with potential future evolution to system for piloted Mars vehicles. This program was initiated in 1991 with a very modest effort identified with nuclear thermal propulsion (NTP); however, NEP is also an integral part of this program and builds upon NASA's Base Research and Technology Program in power and electric propulsion as well as the SP-100 space nuclear power program. The NEP Program will establish the feasibility and practicality of electric propulsion for robotic and piloted solar system exploration. The performance objectives are high specific impulse (200 greater than I(sub sp) greater than 10000 s), high efficiency (over 0.50), and low specific mass. The planning for this program was initially focussed on piloted Mars missions, but has since been redirected to first focus on 100-kW class systems for relatively near-term robotic missions, with possible future evolution to megawatt-and multi-megawatt-class systems applicable to cargo vehicles supporting human missions as well as to the piloted vehicles. This paper reviews current plans and recent progress for the overall nuclear electric propulsion project and closely related activities. 33 refs

  8. 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

  9. Robust Exploration and Commercial Missions to the Moon Using Nuclear Thermal Rocket Propulsion and Lunar Liquid Oxygen Derived from FeO-Rich Pyroclasitc Deposits

    Science.gov (United States)

    Borowski, Stanley K.; Ryan, Stephen W.; Burke, Laura M.; McCurdy, David R.; Fittje, James E.; Joyner, Claude R.

    2018-01-01

    The nuclear thermal rocket (NTR) has frequently been identified as a key space asset required for the human exploration of Mars. This proven technology can also provide the affordable access through cislunar space necessary for commercial development and sustained human presence on the Moon. It is a demonstrated technology capable of generating both high thrust and high specific impulse (I(sub sp) approx. 900 s) twice that of today's best chemical rockets. Nuclear lunar transfer vehicles-consisting of a propulsion stage using three approx. 16.5-klb(sub f) small nuclear rocket engines (SNREs), an in-line propellant tank, plus the payload-are reusable, enabling a variety of lunar missions. These include cargo delivery and crewed lunar landing missions. Even weeklong ''tourism'' missions carrying passengers into lunar orbit for a day of sightseeing and picture taking are possible. The NTR can play an important role in the next phase of lunar exploration and development by providing a robust in-space lunar transportation system (LTS) that can allow initial outposts to evolve into settlements supported by a variety of commercial activities such as in-situ propellant production used to supply strategically located propellant depots and transportation nodes. The use of lunar liquid oxygen (LLO2) derived from iron oxide (FeO)-rich volcanic glass beads, found in numerous pyroclastic deposits on the Moon, can significantly reduce the launch mass requirements from Earth by enabling reusable, surface-based lunar landing vehicles (LLVs)that use liquid oxygen and hydrogen (LO2/LH2) chemical rocket engines. Afterwards, a LO2/LH2 propellant depot can be established in lunar equatorial orbit to supply the LTS. At this point a modified version of the conventional NTR-called the LO2-augmented NTR, or LANTR-is introduced into the LTS allowing bipropellant operation and leveraging the mission benefits of refueling with lunar-derived propellants for Earth return. The bipropellant LANTR

  10. Robust Exploration and Commercial Missions to the Moon Using LANTR Propulsion and Lunar Liquid Oxygen Derived from FeO-Rich Pyroclastic Deposits

    Science.gov (United States)

    Borowski, Stanley K.; Ryan, Stephen W.; Burke, Laura M.; McCurdy, David R.; Fittje, James E.; Joyner, Claude R.

    2017-01-01

    The nuclear thermal rocket (NTR) has frequently been identified as a key space asset required for the human exploration of Mars. This proven technology can also provide the affordable access through cislunar space necessary for commercial development and sustained human presence on the Moon. It is a demonstrated technology capable of generating both high thrust and high specific impulse (Isp approx.900 s) twice that of todays best chemical rockets. Nuclear lunar transfer vehicles consisting of a propulsion stage using three approx.16.5 klbf Small Nuclear Rocket Engines (SNREs), an in-line propellant tank, plus the payload can enable a variety of reusable lunar missions. These include cargo delivery and crewed lunar landing missions. Even weeklong tourism missions carrying passengers into lunar orbit for a day of sightseeing and picture taking are possible. The NTR can play an important role in the next phase of lunar exploration and development by providing a robust in-space lunar transportation system (LTS) that can allow initial outposts to evolve into settlements supported by a variety of commercial activities such as in-situ propellant production used to supply strategically located propellant depots and transportation nodes. The use of lunar liquid oxygen (LLO2) derived from iron oxide (FeO)-rich volcanic glass beads, found in numerous pyroclastic deposits on the Moon, can significantly reduce the launch mass requirements from Earth by enabling reusable, surface-based lunar landing vehicles (LLVs) using liquid oxygen/hydrogen (LO2/H2) chemical rocket engines. Afterwards, a LO2/H2 propellant depot can be established in lunar equatorial orbit to supply the LTS. At this point a modified version of the conventional NTR called the LOX-augmented NTR, or LANTR is introduced into the LTS allowing bipropellant operation and leveraging the mission benefits of refueling with lunar-derived propellants for Earth return. The bipropellant LANTR engine utilizes the large

  11. Internet use during childhood and the ecological techno-subsystem

    Directory of Open Access Journals (Sweden)

    Genevieve Marie Johnson

    2008-12-01

    Full Text Available Research findings suggest both positive and negative developmental consequences of Internet use during childhood (e.g., playing video games have been associated with enhanced visual skills as well as increased aggression. Several studies have concluded that environmental factors mediate the developmental impact of childhood online behaviour. From an ecological perspective, we propose the techno-subsystem, a dimension of the microsystem (i.e., immediate environments. The techno-subsystem includes child interaction with both living (e.g., peers and nonliving (e.g., hardware elements of communication, information, and recreation technologies in direct environments. By emphasizing the role of technology in child development, the ecological techno-subsystem encourages holistic exploration of the developmental consequences of Internet use (and future technological advances during childhood. L’usage d’Internet chez les enfants et le sous-système Techno écologique Résumé : Les résultats de recherche semblent indiquer que l’usage d’Internet chez les enfants aurait des conséquences développementales qui soit à la fois positives et négatives (ex. : l’usage des jeux vidéo auraient été associés à un accroissement des habileté visuelles ainsi qu’à un accroissement de l’agressivité. Plusieurs études ont aussi conclue que l’impact du comportement des enfants quand il sont en ligne sur leur développement serait affecté par des facteurs environnementaux. Dans une perspective écologique, nous proposons le sous-système Techno, une dimension du microsystème (ex :. les environnements immédiats. Le sous-système Techno comprend l’interaction de l’enfant avec des éléments vivants (e. : les paires et non vivants (ex; les ordinateurs de communication, d’information et de technologie de jeux dans des environnements directes.

  12. A development and integration analysis of commercial and in-house control subsystems

    International Nuclear Information System (INIS)

    Moore, D.M.; Dalesio, L.R.

    1998-01-01

    The acquisition and integration of commercial automation and control subsystems in physics research is becoming more common. It is presumed these systems present lower risk and less cost. This paper studies four subsystems used in the Accelerator Production of Tritium (APT) Low Energy Demonstration Accelerator (LEDA) at the Los Alamos National Laboratory (LANL). The radio frequency quadrupole (RFQ) resonance-control cooling subsystem (RCCS), the high-power RF subsystem and the RFQ vacuum subsystem were outsourced; the low-level RF (LLRF) subsystem was developed in-house. Based on the authors experience a careful evaluation of the costs and risks in acquisition, implementation, integration, and maintenance associated with these approaches is given

  13. A Step by Step Approach for Evaluating the Reliability of the Main Engine Lube Oil System for a Ship's Propulsion System

    Directory of Open Access Journals (Sweden)

    Mohan Anantharaman

    2014-09-01

    Full Text Available Effective and efficient maintenance is essential to ensure reliability of a ship's main propulsion system, which in turn is interdependent on the reliability of a number of associated sub- systems. A primary step in evaluating the reliability of the ship's propulsion system will be to evaluate the reliability of each of the sub- system. This paper discusses the methodology adopted to quantify reliability of one of the vital sub-system viz. the lubricating oil system, and development of a model, based on Markov analysis thereof. Having developed the model, means to improve reliability of the system should be considered. The cost of the incremental reliability should be measured to evaluate cost benefits. A maintenance plan can then be devised to achieve the higher level of reliability. Similar approach could be considered to evaluate the reliability of all other sub-systems. This will finally lead to development of a model to evaluate and improve the reliability of the main propulsion system.

  14. Dynamic simulator for PEFC propulsion plant

    Energy Technology Data Exchange (ETDEWEB)

    Hiraide, Masataka; Kaneda, Eiichi; Sato, Takao [Mitsui Engineering & Shipbuilding Co., Ltd., Tokyo (Japan)] [and others

    1996-12-31

    This report covers part of a joint study on a PEFC propulsion system for surface ships, summarized in a presentation to this Seminar, entitled {open_quote}Study on a Polymer Electrolyte Fuel Cell (PEFC) Propulsion System for Surface Ships{close_quotes}, and which envisages application to a 1,500 DWT cargo vessel. The work presented here focuses on a simulation study on PEFC propulsion plant performance, and particularly on the system response to changes in load. Using a dynamic simulator composed of system components including fuel cell, various simulations were executed, to examine the performance of the system as a whole and of the individual system components under quick and large load changes such as occasioned by maneuvering operations and by racing when the propeller emerges above water in heavy sea.

  15. NASA's Launch Propulsion Systems Technology Roadmap

    Science.gov (United States)

    McConnaughey, Paul K.; Femminineo, Mark G.; Koelfgen, Syri J.; Lepsch, Roger A; Ryan, Richard M.; Taylor, Steven A.

    2012-01-01

    Safe, reliable, and affordable access to low-Earth (LEO) orbit is necessary for all of the United States (US) space endeavors. In 2010, NASA s Office of the Chief Technologist commissioned 14 teams to develop technology roadmaps that could be used to guide the Agency s and US technology investment decisions for the next few decades. The Launch Propulsion Systems Technology Area (LPSTA) team was tasked to address the propulsion technology challenges for access to LEO. The developed LPSTA roadmap addresses technologies that enhance existing solid or liquid propulsion technologies and their related ancillary systems or significantly advance the technology readiness level (TRL) of less mature systems like airbreathing, unconventional, and other launch technologies. In developing this roadmap, the LPSTA team consulted previous NASA, military, and industry studies as well as subject matter experts to develop their assessment of this field, which has fundamental technological and strategic impacts for US space capabilities.

  16. Manual wheelchair propulsion patterns on natural surfaces during start-up propulsion.

    Science.gov (United States)

    Koontz, Alicia M; Roche, Bailey M; Collinger, Jennifer L; Cooper, Rory A; Boninger, Michael L

    2009-11-01

    To classify propulsion patterns over surfaces encountered in the natural environment during start-up and compare selected biomechanical variables between pattern types. Case series. National Veterans Wheelchair Games, Minneapolis, MN, 2005. Manual wheelchair users (N=29). Subjects pushed their wheelchairs from a resting position over high-pile carpet, over linoleum, and up a ramp with a 5 degrees incline while propulsion kinematics and kinetics were recorded with a motion capture system and an instrumented wheel. Three raters classified the first 3 strokes as 1 of 4 types on each surface: arc, semicircular (SC), single looping over propulsion (SL), and double looping over propulsion (DL). The Fisher exact test was used to assess pattern changes between strokes and surface type. A multiple analysis of variance test was used to compare peak and average resultant force and moment about the hub, average wheel velocity, stroke frequency, contact angle, and distance traveled between stroke patterns. SL was the most common pattern used during start-up propulsion (44.9%), followed by arc (35.9%), DL (14.1%), and SC (5.1%). Subjects who dropped their hands below the rim during recovery achieved faster velocities and covered greater distances (.016propulsion patterns is a difficult task that should use multiple raters. In addition, propulsion patterns change during start-up, with an arc pattern most prevalent initially. The biomechanical findings in this study agree with current clinical guidelines that recommend training users to drop the hand below the pushrim during recovery.

  17. Designing RF control subsystems using the VXIbus standard

    International Nuclear Information System (INIS)

    Stepp, J.D.; Vong, F.C.; Bridges, J.F.

    1993-01-01

    Various components are being designed to control the RF system of the 7-GeV Advanced Photon Source (APS). The associated control electronics (phase shifters, amplitude modulators, phase detectors, automatic tuning control, and local feedback control) are designed as modular cards with multiple channels for ease of replacement as well as for compact design. Various specifications of the VXIbus are listed and the method used to simplify the design of the control subsystem is shown. A commercial VXI interface board was used to speed the design cycle. Required manpower and actual task times are included. A discussion of the computer architecture and software development of the device drivers which allowed computer control from a VME processor located in a remote crate operating under the Experimental Physics and Industrial Controls Software (EPICS) program is also presented

  18. Lacie phase 1 Classification and Mensuration Subsystem (CAMS) rework experiment

    Science.gov (United States)

    Chhikara, R. S.; Hsu, E. M.; Liszcz, C. J.

    1976-01-01

    An experiment was designed to test the ability of the Classification and Mensuration Subsystem rework operations to improve wheat proportion estimates for segments that had been processed previously. Sites selected for the experiment included three in Kansas and three in Texas, with the remaining five distributed in Montana and North and South Dakota. The acquisition dates were selected to be representative of imagery available in actual operations. No more than one acquisition per biophase were used, and biophases were determined by actual crop calendars. All sites were worked by each of four Analyst-Interpreter/Data Processing Analyst Teams who reviewed the initial processing of each segment and accepted or reworked it for an estimate of the proportion of small grains in the segment. Classification results, acquisitions and classification errors and performance results between CAMS regular and ITS rework are tabulated.

  19. The precision segmented reflectors: Moderate mission figure control subsystem

    Science.gov (United States)

    Sevaston, G.; Redding, D.; Lau, K.; Breckenridge, W.; Levine, B.; Nerheim, N.; Sirlin, S.; Kadogawa, H.

    1991-01-01

    A system concept for a space based segmented reflector telescope figure control subsystem is described. The concept employs a two phase architecture in which figure initialization and figure maintenance are independent functions. Figure initialization is accomplished by image sharpening using natural reference targets. Figure maintenance is performed by monitoring the relative positions and alignments of the telescope components using an optical truss. Actuation is achieved using precision positioners. Computer simulation results of figure initialization by pairwise segment coalignment/cophasing and simulated annealing are presented along with figure maintenance results using a wavefront error regulation algorithm. Both functions are shown to perform at acceptable levels for the class of submillimeter telescopes that are serving as the focus of this technology development effort. Component breadboard work as well as plans for a system testbed are discussed.

  20. The Earth Observing System AM Spacecraft - Thermal Control Subsystem

    Science.gov (United States)

    Chalmers, D.; Fredley, J.; Scott, C.

    1993-01-01

    Mission requirements for the EOS-AM Spacecraft intended to monitor global changes of the entire earth system are considered. The spacecraft is based on an instrument set containing the Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER), Clouds and Earth's Radiant Energy System (CERES), Multiangle Imaging Spectro-Radiometer (MISR), Moderate-Resolution Imaging Spectrometer (MODIS), and Measurements of Pollution in the Troposphere (MOPITT). Emphasis is placed on the design, analysis, development, and verification plans for the unique EOS-AM Thermal Control Subsystem (TCS) aimed at providing the required environments for all the onboard equipment in a densely packed layout. The TCS design maximizes the use of proven thermal design techniques and materials, in conjunction with a capillary pumped two-phase heat transport system for instrument thermal control.

  1. FireSignal application Node for subsystem control

    Czech Academy of Sciences Publication Activity Database

    Duarte, A.S.; Santos, B.; Pereira, T.; Carvalho, B.B.; Fernandes, H.; Neto, A.; Janky, Filip; Cahyna, Pavel; Písačka, Jan; Hron, Martin

    2010-01-01

    Roč. 85, 3-4 (2010), s. 496-499 ISSN 0920-3796. [IAEA Technical Meeting on Control , Data Acquisition and Remote Participation for Fusion Research/7th./. Aix – en – Provence, 15.06.2009-19.06.2009] Institutional research plan: CEZ:AV0Z20430508 Keywords : Subsystems * CODAC * FireSignal * Java * Remote operation Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.143, year: 2010 http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V3C-4YYGPR8-4&_user=6542793&_coverDate=07%2F31%2F2010&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_acct=C000070123&_version=1&_urlVersion=0&_userid=6542793&md5=899631b6e2f4d05b21b04bde3cfb8e65&searchtype=a

  2. Mid Infrared Instrument cooler subsystem test facility overview

    Science.gov (United States)

    Moore, B.; Zan, J.; Hannah, B.; Chui, T.; Penanen, K.; Weilert, M.

    2017-12-01

    The Cryocooler for the Mid Infrared Instrument (MIRI) on the James Webb Space Telescope (JWST) provides cooling at 6.2K on the instrument interface. The cooler system design has been incrementally documented in previous publications [1][2][3][4][5]. It has components that traverse three primary thermal regions on JWST: Region 1, approximated by 40K; Region 2, approximated by 100K; and Region 3, which is at the allowable flight temperatures for the spacecraft bus. However, there are several sub-regions that exist in the transition between primary regions and at the heat reject interfaces of the Cooler Compressor Assembly (CCA) and Cooler Control Electronics Assembly (CCEA). The design and performance of the test facility to provide a flight representative thermal environment for acceptance testing and characterization of the complete MIRI cooler subsystem are presented.

  3. Designing a New Raster Sub-System for GRASS-7

    Directory of Open Access Journals (Sweden)

    Martin Hruby

    2012-03-01

    Full Text Available The paper deals with a design of a new raster sub-system intended for modern GIS systems open for client and server operation, database connection and strong application interface (API. Motivation for such a design comes from the current state of API working in GRASS 6. If found attractive, the here presented design and its implementation (referred as RG7 may be integrated to the future new generation of the GRASS Geographical Information System version 7-8. The paper describes in details the concept of raster tiling, computer storage of rasters and basic raster access procedures. Finally, the paper gives a simple benchmarking experiment of random read access to raster files imported from the Spearfish dataset. The experiment compares the early implementation of RG7 with the current implementation of rasters in GRASS 6. As the result, the experiment shows the RG7 to be significantly faster than GRASS in random read access to large raster files.

  4. An inverter/controller subsystem optimized for photovoltaic applications

    Science.gov (United States)

    Pickrell, R. L.; Merrill, W. C.; Osullivan, G.

    1978-01-01

    Conversion of solar array dc power to ac power stimulated the specification, design, and simulation testing of an inverter/controller subsystem tailored to the photovoltaic power source characteristics. This paper discusses the optimization of the inverter/controller design as part of an overall Photovoltaic Power System (PPS) designed for maximum energy extraction from the solar array. The special design requirements for the inverter/controller include: (1) a power system controller (PSC) to control continuously the solar array operating point at the maximum power level based on variable solar insolation and cell temperatures; and (2) an inverter designed for high efficiency at rated load and low losses at light loadings to conserve energy. It must be capable of operating connected to the utility line at a level set by an external controller (PSC).

  5. Progress report for the scintillator plate calorimeter subsystem

    International Nuclear Information System (INIS)

    1990-01-01

    This report covers the work completed in FY90 by ANL staff and those of Westinghouse STC and BICRON Corporation under subcontract to ANL towards the design of a compensating calorimeter based on the use of scintillator plate as the sensitive medium. It is presented as five task sections dealing with respectively mechanical design; simulation studies; optical system design; electronics development; development of rad hard plastic scintillator and wavelength shifter and a summary. The work carried out by the University of Tennessee under a subcontract from ANL is reported separately. Finally, as principal institution with responsibility for the overall management of this subsystem effort, the summary here reports the conclusions resulting from the work of the collaboration and their impact on our proposed direction of effort in FY91. This proposal, for obvious reasons is given separately

  6. Fragmented network subsystem with traffic filtering for microkernel environment

    Directory of Open Access Journals (Sweden)

    Anna Urievna Budkina

    2016-06-01

    Full Text Available The TCP/IP stack in a microkernel operating system executed in a user space, which requires the development of a distributed network infrastructure within a single software environment. Its functions are the organization of interaction between the components of the stack with different processes, as well as the organization of filtering mechanisms and routing of internal network traffic. Use of architectural approaches applicable in monolithic-modular systems is impossible, because the network stack is not a shareable component of the system. As a consequence, the microkernel environment requires development of special network subsystem. In this work we provide overview of major conceptions of network architectures in microkernel environments. Also, we provide own architecture which supports filtering of internal network traffic. We evaluate the architecture by development of high-performance "key-value" store.

  7. Mars Sample Return Using Solar Sail Propulsion

    Science.gov (United States)

    Johnson, Les; Macdonald, Malcolm; Mcinnes, Colin; Percy, Tom

    2012-01-01

    Many Mars Sample Return (MSR) architecture studies have been conducted over the years. A key element of them is the Earth Return Stage (ERS) whose objective is to obtain the sample from the Mars Ascent Vehicle (MAV) and return it safely to the surface of the Earth. ERS designs predominantly use chemical propulsion [1], incurring a significant launch mass penalty due to the low specific impulse of such systems coupled with the launch mass sensitivity to returned mass. It is proposed to use solar sail propulsion for the ERS, providing a high (effective) specific impulse propulsion system in the final stage of the multi-stage system. By doing so to the launch mass of the orbiter mission can be significantly reduced and hence potentially decreasing mission cost. Further, solar sailing offers a unique set of non-Keplerian low thrust trajectories that may enable modifications to the current approach to designing the Earth Entry Vehicle by potentially reducing the Earth arrival velocity. This modification will further decrease the mass of the orbiter system. Solar sail propulsion uses sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like surface made of a lightweight, reflective material. The continuous photonic pressure provides propellantless thrust to conduct orbital maneuvering and plane changes more efficiently than conventional chemical propulsion. Because the Sun supplies the necessary propulsive energy, solar sails require no onboard propellant, thus reducing system mass. This technology is currently at TRL 7/8 as demonstrated by the 2010 flight of the Japanese Aerospace Exploration Agency, JAXA, IKAROS mission. [2

  8. 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.

  9. Implementation of amplifiers, control and safety subsystems of radiofrequency system of VINCY Cyclotron

    International Nuclear Information System (INIS)

    Drndarevic, V.; Obradovic, M.; Samardic, B.; Djuric, B.; Bojovic, B.; Trajic, M.I.; Golubicic, Z.; Smiljakovic, V.

    1996-01-01

    Concept and design of power amplifiers, control subsystem and safety subsystems for the RF system of the VINCY cyclotron are described. The power amplifiers subsystem consists of two amplifiers of 30 kW nominal power that operate in class B or class C. High stability of voltage amplitude of 5x10 -4 and phase stability between two resonators better than ± 0.5 0 in the range from 16.5 to 31 MHz is being providing by RF control subsystem. Autonomous safety system serves to protect staff from high voltage and to protect equipment from damage. (author)

  10. Subsystem response determination for the US NRC Seismic Safety Margins Research Program

    International Nuclear Information System (INIS)

    Johnson, J.J.

    1979-01-01

    The initial portion of the task described deals with a definition of the state-of-the-art of seismic qualification methods for subsystems. Too facilitate treatment of this broad class of subsystems, three classifications have been identified: multiply supported subsystems (e.g., piping systems); mechanical components (e.g., valves, pumps, control rod drives, hydraulic systems, etc.); and electrical components (e.g., electrical control panels). Descriptions of the available analysis and/or testing techniques for the above classifications are sought. The results of this assessment will be applied to the development of structural subsystem transfer functions

  11. Local control station for development, testing and maintenance of mirror fusion facility subsystem controls

    International Nuclear Information System (INIS)

    Ables, E.; Kelly, M.F.

    1985-01-01

    A Local Control Station (LCS) was designed and built to provide a simplified ad easily configurable means of controlling any Mirror Fusion Test Facility (MFTF-B) subsystem for the purpose of development, testing and maintenance of the subsystem. All MFTF-B Subsystems incorporate at least one Local Control Computer (LCC) that is connected to and accepts high level commands from one of the Supervisory Control and Diagnostic System (SCDS) computers. The LCS connects directly to the LCC in place of SCDS. The LCS communicates with the subsystem hardware using the same SCDS commands that the local control computer recognizes and as such requires no special configuration of the LCC

  12. THE ANALYSIS OF BEEF CATTLE SUBSYSTEM AGRIBUSINESS IMPLEMENTATION IN CENTRAL JAVA PROVINCE, INDONESIA

    Directory of Open Access Journals (Sweden)

    T. Ekowati

    2014-10-01

    Full Text Available The study aimed to analyze the implementation of subsystem agribusiness on the beef cattlefarming in Central Java. Five districts (Rembang, Blora, Grobogan, Boyolali and Wonogiri werepurposively chosen based on the value of Location Quotient (LQ. The study was conducted usingquota sampling method. Forty respondents of each district were chosen randomly using quota sampling.Data were analyzed through Structural Equation Model (SEM. The results showed that each subsystemagribusiness had adequate potential score. The score of 0.693, 0.721, 0.684, 0.626, and 0.691 were givenfor up-stream subsystem, on-farm, down-stream subsystem, marketing and supporting institution,respectively. The results showed that the SEM model was feasible with Chi-Square value=0.952;RMSEA=0.000; Probability =0.621 and TL1=1.126. The significant results of Critical Ratio (CR were:up-stream subsystem to the on-farm agribusiness; on-farm subsystem to down-stream agribusiness;down-stream subsystem to the farmer’s income; marketing subsystem to the up-stream agribusiness andSupporting Institution to the marketing subsystem and down-stream agribusiness. The conclusion ofresearch indicated that the implementation of beef cattle subsystem agribusiness had adequate index andgive positive effect to the beef cattle agribusiness.

  13. Cryogenic propulsion for lunar and Mars missions

    Science.gov (United States)

    Redd, Larry

    1988-01-01

    Future missions to the moon and Mars have been investigated with regard to propulsion system selection. The results of this analysis show that near state-of-the-art LO2/LH2 propulsion technology provides a feasible means of performing lunar missions and trans-Mars injections. In other words, existing cryogenic space engines with certain modifications and product improvements would be suitable for these missions. In addition, present day cryogenic system tankage and structural weights appear to scale reasonably when sizing for large payload and high energy missions such as sending men to Mars.

  14. Electric rail gun application to space propulsion

    International Nuclear Information System (INIS)

    Barber, J.P.

    1979-01-01

    The paper examines the possibility of using the DC electric gun principles as a space vehicle propulsion system, capable of producing intermediate thrust levels. The application of an electromagnetic launch technique, called the DC electric rail gun, to the space propulsion concept of O'Neill, is examined. It is determined that the DC electric rail gun offers very high projectile accelerations and a very significant potential for reducing the size and mass of a reaction motor for space application. A detailed description of rail gun principles is given and some simple expressions for the accelerating force, gun impedance, power supply requirements, and system performance are discussed

  15. Distributed Multi-propulsion Units System

    OpenAIRE

    原田, 正志; HARADA, Masashi

    2002-01-01

    Reduction of the weight of the propulsion system is important in the design of a stratospheric airship. However, it also important to increaseefficiency of the system because available energy generated by solar cells on the hull is quite limited. One solution to increase efficiency of the propulsion system is to use a stern propeller, the propeller mounted on the stern of the hull as shown in Figure 1. Mounted on the stern of the hull, the stern propeller is merged with the boundary layer of ...

  16. Superconducting DC homopolar motors for ship propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Heiberger, M.; Reed, M.R.; Creedon, W.P.; O' Hea, B.J. [General Atomic (United States)

    2000-07-01

    Superconducting DC homopolar motors have undergone recent advances in technology, warranting serious consideration of their use for ship propulsion. Homopolar motor propulsion is now practical because of two key technology developments: cryogen-free superconducting refrigeration and high performance motor fiber brushes. These compact motors are ideal for podded applications, where reduced drag and fuel consumption are predicted. In addition, the simple DC motor controller is more efficient and reliable compared with AC motor controllers. Military ships also benefit from increased stealth implicit in homopolar DC excitation, which also allows the option for direct hull or pod mounting. (authors)

  17. Advanced electrostatic ion thruster for space propulsion

    Science.gov (United States)

    Masek, T. D.; Macpherson, D.; Gelon, W.; Kami, S.; Poeschel, R. L.; Ward, J. W.

    1978-01-01

    The suitability of the baseline 30 cm thruster for future space missions was examined. Preliminary design concepts for several advanced thrusters were developed to assess the potential practical difficulties of a new design. Useful methodologies were produced for assessing both planetary and earth orbit missions. Payload performance as a function of propulsion system technology level and cost sensitivity to propulsion system technology level are among the topics assessed. A 50 cm diameter thruster designed to operate with a beam voltage of about 2400 V is suggested to satisfy most of the requirements of future space missions.

  18. Laser propulsion activity in South Africa

    CSIR Research Space (South Africa)

    Michaelis, MM

    2006-07-01

    Full Text Available hemisphere are becoming excited at the prospect of a considerable reduction in the cost of launch to low Earth orbit (LEO) by means of laser propulsion (LP) (see ref. 1). We argue here that developing nations also should assess the potential of a cheaper... of the grandiose scheme of ‘Space Port Kilimanjaro’ (Fig. 5), envis- aged by various authors becoming a reality, South African scien- tists, engineers and financiers would benefit. Kilimanjaro is regarded by some13 as the prime location for laser propulsion...

  19. 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

  20. Advanced Propulsion Physics Lab: Eagleworks Investigations

    Science.gov (United States)

    Scogin, Tyler

    2014-01-01

    Eagleworks Laboratory is an advanced propulsions physics laboratory with two primary investigations currently underway. The first is a Quantum Vacuum Plasma Thruster (QVPT or Q-thrusters), an advanced electric propulsion technology in the development and demonstration phase. The second investigation is in Warp Field Interferometry (WFI). This is an investigation of Dr. Harold "Sonny" White's theoretical physics models for warp field equations using optical experiments in the Electro Optical laboratory (EOL) at Johnson Space Center. These investigations are pursuing technology necessary to enable human exploration of the solar system and beyond.

  1. Artist's concept of Antimatter propulsion system

    Science.gov (United States)

    1999-01-01

    This is an artist's rendition of an antimatter propulsion system. Matter - antimatter arnihilation offers the highest possible physical energy density of any known reaction substance. It is about 10 billion times more powerful than that of chemical engergy 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 on-going and making some strides, but production of this as a propulsion system is far into the future.

  2. Multidisciplinary approach to materials selection for bipropellant ...

    Indian Academy of Sciences (India)

    The second method to cool combustion chamber is the unsteady state ... propellant. Engines that have this kind of cooling are, for .... tion velocity and CAbl is ablation heat coefficient. ... propellant flow, TPS and control volume lead to Eq. (9).

  3. Low-Thrust Bipropellant Engine Technology.

    Science.gov (United States)

    1980-08-01

    Non-Destructive Testing OD Outside Diameter xv tr. GLOSSARY (cont.J ODE One Dimensional Equilibrium ODK One Dimensional Kinetics Pc Thrust Chamber...performance (280 sec steady- state, 220 sec pulsing) have not yet been collectively achieved, but should be obtainable with further development activities...even at nozzle area ratios up to 400:1. The influence of nozzle kinetics (i.e., equilibrium versus frozen flow and ODK ) are noted to be a much more

  4. Hybrid Propulsion Technology for Robotic Science Missions, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — C3 Propulsion's Hybrid Propulsion Technology will be applied to a NASA selected Sample Return Mission. Phase I will demonstrate Proof-of-Principle and Phase II will...

  5. The synchronous long-stator propulsion system for TRANSRAPID; Langstator-Synchronmotorantrieb des TRANSRAPID

    Energy Technology Data Exchange (ETDEWEB)

    Henning, U [Siemens AG Verkehrstechnik, Erlangen (Germany). Geschaeftsgebiet Fahrzeuge Fernverkehr; Kamp, P G [Siemens AG, Erlangen (Germany). Projektierung und Entwicklung von Stromrichtergeraeten fuer die Bahnstromversorgung; Hochleitner, J [Siemens AG, Erlangen (Germany). Abt. Kombinationstechnik

    1996-12-31

    The synchronous long-stator motor for the maglev vehicle TRANSRAPID is a propulsion system with proven service maturity. The following paper describes the structure of the propulsion system proposed for maglev revenue service lines and how it meets the requirements for modular design, operation of several vehicles on one line, double-end feeding of power from adjacent substations, as well as for optimum maglev operation with minimum fault susceptibility. The overall concept is described and prototypes incorporating new technologies are presented for the various subsystems and components. The main focus is on the converter and control systems. (orig.) [Deutsch] Der Langstator-Synchronmotorantrieb des TRANSRAPID stellt ein einsatzreifes System dar. Die fuer Anwendungsstrecken entwickelte Struktur des Antriebssystems wird beschrieben. Mit ihr werden die Einsatzanforderungen wie modulare Gestaltung, Betrieb mehrerer Fahrzeuge auf eine Strecke, Doppelspeisung aus benachbarten Unterwerken sowie optimaler und stoerungsarmer Betrieb erfuellt. Neben der Beschreibung des Gesamtkonzeptes werden auch Prototypen fuer Teilsysteme und Komponenten auf der Basis fortschrittlicher Technologien vorgestellt. Schwerpunkte sind dabei Umrichter- und Regelungstechnik. (orig.)

  6. Executive Summary of Propulsion on the Orion Abort Flight-Test Vehicles

    Science.gov (United States)

    Jones, Daniel S.; Brooks, Syri J.; Barnes, Marvin W.; McCauley, Rachel J.; Wall, Terry M.; Reed, Brian D.; Duncan, C. Miguel

    2012-01-01

    The National Aeronautics and Space Administration Orion Flight Test Office was tasked with conducting a series of flight tests in several launch abort scenarios to certify that the Orion Launch Abort System is capable of delivering astronauts aboard the Orion Crew Module to a safe environment, away from a failed booster. The first of this series was the Orion Pad Abort 1 Flight-Test Vehicle, which was successfully flown on May 6, 2010 at the White Sands Missile Range in New Mexico. This report provides a brief overview of the three propulsive subsystems used on the Pad Abort 1 Flight-Test Vehicle. An overview of the propulsive systems originally planned for future flight-test vehicles is also provided, which also includes the cold gas Reaction Control System within the Crew Module, and the Peacekeeper first stage rocket motor encased within the Abort Test Booster aeroshell. Although the Constellation program has been cancelled and the operational role of the Orion spacecraft has significantly evolved, lessons learned from Pad Abort 1 and the other flight-test vehicles could certainly contribute to the vehicle architecture of many future human-rated space launch vehicles

  7. Overview and future prospects of laser plasma propulsion technology

    International Nuclear Information System (INIS)

    Zheng Zhiyuan; Lu Xin; Zhang Jie

    2003-01-01

    Due to its high cost, low efficiency, complex operation and unsatisfactory recycling, traditional rocket propulsion by chemical fuels has hindered the exploration of outer space to further limits. With the rapid development of laser and space technology, the new technology of laser propulsion exhibits unique advantages and prospects. The mechanism and current development of laser plasma propulsion are reviewed, with mention of the technical problems and focus issues of laser plasma in micro-flight propulsion

  8. Laser Propulsion - Is it another myth or a real potential?

    International Nuclear Information System (INIS)

    Cook, Joung R.

    2008-01-01

    This paper discusses different principles of inducing propulsive power using lasers and examines the performance limits along with pros and cons with respect to different space propulsion applications: satellite launching, orbital transfer, space debris clearing, satellite propulsion, and space travels. It concludes that a use of electrical propulsion, in conjunction with laser power beaming, is the most feasible application with technological and economic advantages for commercial use within the next decades

  9. 46 CFR 121.620 - Propulsion engine control systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Propulsion engine control systems. 121.620 Section 121... Propulsion engine control systems. (a) A vessel must have two independent means of controlling each propulsion engine. Control must be provided for the engine speed, direction of shaft rotation, and engine...

  10. 46 CFR 184.620 - Propulsion engine control systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Propulsion engine control systems. 184.620 Section 184... Communications Systems § 184.620 Propulsion engine control systems. (a) A vessel must have two independent means of controlling each propulsion engine. Control must be provided for the engine speed, direction of...

  11. Prospective application of laser plasma propulsion in rocket technology

    International Nuclear Information System (INIS)

    Lu Xin; Zhang Jie; Li Yingjun

    2002-01-01

    Interest in laser plasma propulsion is growing intensively. The interaction of high intensity short laser pulses with materials can produce plasma expansion with a velocity of hundreds of km/s. The specific impulse of ablative laser propulsion can be many tens of times greater than that of chemical rockets. The development and potential application of laser plasma propulsion are discussed

  12. In-Space Propulsion Technologies for Robotic Exploration of the Solar System

    Science.gov (United States)

    Johnson, Les; Meyer, Rae Ann; Frame, Kyle

    2006-01-01

    Supporting NASA's Science Mission Directorate, the In-Space Propulsion Technology Program is developing the next generation of space propulsion technologies for robotic, deep-space exploration. Recent technological advancements and demonstrations of key, high-payoff propulsion technologies have been achieved and will be described. Technologies under development and test include aerocapture, solar electric propulsion, solar sail propulsion, and advanced chemical propulsion.

  13. New propulsion components for electric vehicles

    Science.gov (United States)

    Secunde, R. R.

    1983-01-01

    Improved component technology is described. This includes electronically commutated permanent magnet motors of both drum and disk configurations, an unconventional brush commutated motor, ac induction motors, various controllers, transmissions and complete systems. One or more of these approaches to electric vehicle propulsion may eventually displace presently used controllers and brush commutated dc motors. Previously announced in STAR as N83-25982

  14. Heavy Ion Propulsion in the Megadalton Range

    Science.gov (United States)

    2006-11-01

    atomizacidn electrostdtica, Universidad Carlos III, Madrid, Spain (2006) 15. D. Garoz, "Sintesis, estudio y mezclas de nuevos combustibles basados en...propellants for electrical propulsion from Taylor cones in vacuo), Proyecto fin de carrera (Senior Thesis), Universidad Politecnica de Madrid, Marzo 2004

  15. Advanced propulsion system for hybrid vehicles

    Science.gov (United States)

    Norrup, L. V.; Lintz, A. T.

    1980-01-01

    A number of hybrid propulsion systems were evaluated for application in several different vehicle sizes. A conceptual design was prepared for the most promising configuration. Various system configurations were parametrically evaluated and compared, design tradeoffs performed, and a conceptual design produced. Fifteen vehicle/propulsion systems concepts were parametrically evaluated to select two systems and one vehicle for detailed design tradeoff studies. A single hybrid propulsion system concept and vehicle (five passenger family sedan)were selected for optimization based on the results of the tradeoff studies. The final propulsion system consists of a 65 kW spark-ignition heat engine, a mechanical continuously variable traction transmission, a 20 kW permanent magnet axial-gap traction motor, a variable frequency inverter, a 386 kg lead-acid improved state-of-the-art battery, and a transaxle. The system was configured with a parallel power path between the heat engine and battery. It has two automatic operational modes: electric mode and heat engine mode. Power is always shared between the heat engine and battery during acceleration periods. In both modes, regenerative braking energy is absorbed by the battery.

  16. Statistical modelling for ship propulsion efficiency

    DEFF Research Database (Denmark)

    Petersen, Jóan Petur; Jacobsen, Daniel J.; Winther, Ole

    2012-01-01

    This paper presents a state-of-the-art systems approach to statistical modelling of fuel efficiency in ship propulsion, and also a novel and publicly available data set of high quality sensory data. Two statistical model approaches are investigated and compared: artificial neural networks...

  17. Reconfigurable Control of a Ship Propulsion Plant

    DEFF Research Database (Denmark)

    Blanke, M.; Izadi-Zamanabadi, Roozbeh

    1998-01-01

    -tolerant control is a fairly new area. Thise paper presents a ship propulsion system as a benchmark that should be useful as a platform for the development of new ideas and a comparison of methods. The benchmark has two main elements. One is the development of efficient FDI algorithms, and the other...

  18. Magnetic artificial cilia for microfluidic propulsion

    NARCIS (Netherlands)

    Khaderi, S.N.; den Toonder, J.M.J.; Onck, P.R.

    2015-01-01

    Cilia are tiny hair-like structures that cover the surfaces of biological cells. One of their functions is to generate flow. Artificial cilia are mechanical actuators that are designed to mimic the motion of natural cilia in order to create fluid transport in microchannels. These fluid propulsion

  19. Magnetic Artificial Cilia for Microfluidic Propulsion

    NARCIS (Netherlands)

    Khaderi, Syed N.; den Toonder, Jaap M. J.; Onck, Patrick R.; Bordas, Stéphane P.A.; Balint, Daniel S.

    2015-01-01

    Cilia are tiny hair-like structures that cover the surfaces of biological cells. One of their functions is to generate flow. Artificial cilia are mechanical actuators that are designed to mimic the motion of natural cilia in order to create fluid transport in microchannels. These fluid propulsion

  20. Supersonic propulsion technology. [variable cycle engines

    Science.gov (United States)

    Powers, A. G.; Coltrin, R. E.; Stitt, L. E.; Weber, R. J.; Whitlow, J. B., Jr.

    1979-01-01

    Propulsion concepts for commercial supersonic transports are discussed. It is concluded that variable cycle engines, together with advanced supersonic inlets and low noise coannular nozzles, provide good operating performance for both supersonic and subsonic flight. In addition, they are reasonably quiet during takeoff and landing and have acceptable exhaust emissions.

  1. An Analysis of Rocket Propulsion Testing Costs

    Science.gov (United States)

    Ramirez, Carmen; Rahman, Shamim

    2010-01-01

    The primary mission at NASA Stennis Space Center (SSC) is rocket propulsion testing. Such testing is commonly characterized as one of two types: production testing for certification and acceptance of engine hardware, and developmental testing for prototype evaluation or research and development (R&D) purposes. For programmatic reasons there is a continuing need to assess and evaluate the test costs for the various types of test campaigns that involve liquid rocket propellant test articles. Presently, in fact, there is a critical need to provide guidance on what represents a best value for testing and provide some key economic insights for decision-makers within NASA and the test customers outside the Agency. Hence, selected rocket propulsion test databases and references have been evaluated and analyzed with the intent to discover correlations of technical information and test costs that could help produce more reliable and accurate cost projections in the future. The process of searching, collecting, and validating propulsion test cost information presented some unique obstacles which then led to a set of recommendations for improvement in order to facilitate future cost information gathering and analysis. In summary, this historical account and evaluation of rocket propulsion test cost information will enhance understanding of the various kinds of project cost information; identify certain trends of interest to the aerospace testing community.

  2. MSFC Propulsion Systems Department Knowledge Management Project

    Science.gov (United States)

    Caraccioli, Paul A.

    2007-01-01

    This slide presentation reviews the Knowledge Management (KM) project of the Propulsion Systems Department at Marshall Space Flight Center. KM is needed to support knowledge capture, preservation and to support an information sharing culture. The presentation includes the strategic plan for the KM initiative, the system requirements, the technology description, the User Interface and custom features, and a search demonstration.

  3. Propulsion via flexible flapping in granular media

    Science.gov (United States)

    Peng, Zhiwei; Ding, Yang; Pietrzyk, Kyle; Elfring, Gwynn; Pak, On Shun

    2017-11-01

    Biological locomotion in nature is often achieved by the interaction between a flexible body and its surrounding medium. The interaction of a flexible body with granular media is less understood compared with viscous fluids partially due to its complex rheological properties. In this work, we explore the effect of flexibility on granular propulsion by considering a simple mechanical model in which a rigid rod is connected to a torsional spring that is under a displacement actuation using a granular resistive force theory. Through a combined numerical and asymptotic investigation, we characterize the propulsive dynamics of such a flexible flapper in relation to the actuation amplitude and spring stiffness, and we compare these dynamics with those observed in a viscous fluid. In addition, we demonstrate that the maximum possible propulsive force can be obtained in the steady propulsion limit with a finite spring stiffness and large actuation amplitude. These results may apply to the development of synthetic locomotive systems that exploit flexibility to move through complex terrestrial media. Funding for Z.P. and Y.D. was partially provided by NSFC 394 Grant No. 11672029 and NSAF-NSFC Grant No. U1530401.

  4. On-Orbit Propulsion OMS/RCS

    Science.gov (United States)

    Hurlbert, Eric A.

    2001-01-01

    This slide presentation reviews the Space Shuttle's On-Orbit Propulsion systems: the Orbital Maneuvering System (OMS) and the Reaction Control System (RCS). The functions of each of the systems is described, and the diagrams of the systems are presented. The OMS/RCS thruster is detailed and a trade study comparison of non-toxic propellants is presented.

  5. Numerical analysis of a waterjet propulsion system

    NARCIS (Netherlands)

    Bulten, N.W.H.

    2006-01-01

    A waterjet propulsion system is used to propel ships, using a pump which produces a high speed jet. A standard waterjet installation can be divided into an inlet, a pump and a nozzle. For manoeuvring and reversing purposes an additional steering device can be integrated into the installation. The

  6. A concept of ferroelectric microparticle propulsion thruster

    International Nuclear Information System (INIS)

    Yarmolich, D.; Vekselman, V.; Krasik, Ya. E.

    2008-01-01

    A space propulsion concept using charged ferroelectric microparticles as a propellant is suggested. The measured ferroelectric plasma source thrust, produced mainly by microparticles emission, reaches ∼9x10 -4 N. The obtained trajectories of microparticles demonstrate that the majority of the microparticles are positively charged, which permits further improvement of the thruster

  7. Nuclear propulsion for the space exploration initiative

    International Nuclear Information System (INIS)

    Stanley, M.L.

    1991-01-01

    President Bush's speech of July 20, 1989, outlining a goal to go back to the moon and then Mars initiated the Space Exploration Initiative (SEI). The US Department of Defense (DOD), US Department of Energy (DOE), and NASA have been working together in the planning necessary to initiate a program to develop a nuclear propulsion system. Applications of nuclear technology for in-space transfer of personnel and cargo between Earth orbit and lunar or Martian orbit are being considered as alternatives to chemical propulsion systems. Mission and system concept studies conducted over the past 30 yr have consistently indicated that use of nuclear technology can substantially reduce in-space propellant requirements. A variety of nuclear technology options are currently being studied, including nuclear thermal rockets, nuclear electrical propulsion systems, and hybrid nuclear thermal rockets/nuclear electric propulsion concepts. Concept performance in terms of thrust, weight, power, and efficiency are dependent, and appropriate concept application is mission dependent (i.e., lunar, Mars, cargo, personnel, trajectory, transit time, payload). A comprehensive evaluation of mission application, technology performance capability and maturity, technology development programmatics, and safety characteristics is required to optimize both technology and mission selection to support the Presidential initiative

  8. Measurement Issues In Pulsed Laser Propulsion

    International Nuclear Information System (INIS)

    Sinko, John E.; Scharring, Stefan; Eckel, Hans-Albert; Roeser, Hans-Peter; Sasoh, Akihiro

    2010-01-01

    Various measurement techniques have been used throughout the over 40-year history of laser propulsion. Often, these approaches suffered from inconsistencies in definitions of the key parameters that define the physics of laser ablation impulse generation. Such parameters include, but are not limited to the pulse energy, spot area, imparted impulse, and ablated mass. The limits and characteristics of common measurement techniques in each of these areas will be explored as they relate to laser propulsion. The idea of establishing some standardization system for laser propulsion data is introduced in this paper, so that reported results may be considered and studied by the general community with more certain understanding of particular merits and limitations. In particular, it is the intention to propose a minimum set of requirements a literature study should meet. Some international standards for measurements are already published, but modifications or revisions of such standards may be necessary for application to laser ablation propulsion. Issues relating to development of standards will be discussed, as well as some examples of specific experimental circumstances in which standardization would have prevented misinterpretation or misuse of past data.

  9. Wheelchair propulsion technique at different speeds

    NARCIS (Netherlands)

    Veeger, DirkJan (H. E. J.); van der Woude, L H; Rozendal, R H

    1989-01-01

    To study wheelchair propulsion technique at different speeds, five well-trained subjects propelled a wheelchair on a treadmill. Measurements were made at four belt speeds of 0.56-1.39 m/s and against slopes of 2 and 3 degrees. Cardiorespiratory data were collected. Three consecutive strokes were

  10. The Potential for Ambient Plasma Wave Propulsion

    Science.gov (United States)

    Gilland, James H.; Williams, George J.

    2016-01-01

    A truly robust space exploration program will need to make use of in-situ resources as much as possible to make the endeavor affordable. Most space propulsion concepts are saddled with one fundamental burden; the propellant needed to produce momentum. The most advanced propulsion systems currently in use utilize electric and/or magnetic fields to accelerate ionized propellant. However, significant planetary exploration missions in the coming decades, such as the now canceled Jupiter Icy Moons Orbiter, are restricted by propellant mass and propulsion system lifetimes, using even the most optimistic projections of performance. These electric propulsion vehicles are inherently limited in flexibility at their final destination, due to propulsion system wear, propellant requirements, and the relatively low acceleration of the vehicle. A few concepts are able to utilize the environment around them to produce thrust: Solar or magnetic sails and, with certain restrictions, electrodynamic tethers. These concepts focus primarily on using the solar wind or ambient magnetic fields to generate thrust. Technically immature, quasi-propellantless alternatives lack either the sensitivity or the power to provide significant maneuvering. An additional resource to be considered is the ambient plasma and magnetic fields in solar and planetary magnetospheres. These environments, such as those around the Sun or Jupiter, have been shown to host a variety of plasma waves. Plasma wave propulsion takes advantage of an observed astrophysical and terrestrial phenomenon: Alfven waves. These are waves that propagate in the plasma and magnetic fields around and between planets and stars. The generation of Alfven waves in ambient magnetic and plasma fields to generate thrust is proposed as a truly propellantless propulsion system which may enable an entirely new matrix of exploration missions. Alfven waves are well known, transverse electromagnetic waves that propagate in magnetized plasmas at

  11. Beamed-Energy Propulsion (BEP) Study

    Science.gov (United States)

    George, Patrick; Beach, Raymond

    2012-01-01

    The scope of this study was to (1) review and analyze the state-of-art in beamed-energy propulsion (BEP) by identifying potential game-changing applications, (2) formulate a roadmap of technology development, and (3) identify key near-term technology demonstrations to rapidly advance elements of BEP technology to Technology Readiness Level (TRL) 6. The two major areas of interest were launching payloads and space propulsion. More generally, the study was requested and structured to address basic mission feasibility. The attraction of beamed-energy propulsion (BEP) is the potential for high specific impulse while removing the power-generation mass. The rapid advancements in high-energy beamed-power systems and optics over the past 20 years warranted a fresh look at the technology. For launching payloads, the study concluded that using BEP to propel vehicles into space is technically feasible if a commitment to develop new technologies and large investments can be made over long periods of time. From a commercial competitive standpoint, if an advantage of beamed energy for Earth-to-orbit (ETO) is to be found, it will rest with smaller, frequently launched payloads. For space propulsion, the study concluded that using beamed energy to propel vehicles from low Earth orbit to geosynchronous Earth orbit (LEO-GEO) and into deep space is definitely feasible and showed distinct advantages and greater potential over current propulsion technologies. However, this conclusion also assumes that upfront infrastructure investments and commitments to critical technologies will be made over long periods of time. The chief issue, similar to that for payloads, is high infrastructure costs.

  12. Mirror fusion propulsion system - A performance comparison with alternate propulsion systems for the manned Mars mission

    International Nuclear Information System (INIS)

    Deveny, M.; Carpenter, S.; O'connell, T.; Schulze, N.

    1993-06-01

    The performance characteristics of several propulsion technologies applied to piloted Mars missions are compared. The characteristics that are compared are Initial Mass in Low Earth Orbit (IMLEO), mission flexibility, and flight times. The propulsion systems being compared are both demonstrated and envisioned: Chemical (or Cryogenic), Nuclear Thermal Rocket (NTR) solid core, NTR gas core, Nuclear Electric Propulsion (NEP), and a mirror fusion space propulsion system. The proposed magnetic mirror fusion reactor, known as the Mirror Fusion Propulsion System (MFPS), is described. The description is an overview of a design study that was conducted to convert a mirror reactor experiment at Lawrence Livermore National Lab (LLNL) into a viable space propulsion system. Design principles geared towards minimizing mass and maximizing power available for thrust are identified and applied to the LLNL reactor design, resulting in the MFPS. The MFPS' design evolution, reactor and fuel choices, and system configuration are described. Results of the performance comparison shows that the MFPS minimizes flight time to 60 to 90 days for flights to Mars while allowing continuous return-home capability while at Mars. Total MFPS IMLEO including propellant and payloads is kept to about 1,000 metric tons. 50 refs

  13. Propulsion System and Orbit Maneuver Integration in CubeSats: Trajectory Control Strategies Using Micro Ion Propulsion

    Science.gov (United States)

    Hudson, Jennifer; Martinez, Andres; Petro, Andrew

    2015-01-01

    The Propulsion System and Orbit Maneuver Integration in CubeSats project aims to solve the challenges of integrating a micro electric propulsion system on a CubeSat in order to perform orbital maneuvers and control attitude. This represents a fundamentally new capability for CubeSats, which typically do not contain propulsion systems and cannot maneuver far beyond their initial orbits.

  14. Operationally efficient propulsion system study (OEPSS) data book. Volume 6; Space Transfer Propulsion Operational Efficiency Study Task of OEPSS

    Science.gov (United States)

    Harmon, Timothy J.

    1992-01-01

    This document is the final report for the Space Transfer Propulsion Operational Efficiency Study Task of the Operationally Efficient Propulsion System Study (OEPSS) conducted by the Rocketdyne Division of Rockwell International. This Study task studied, evaluated and identified design concepts and technologies which minimized launch and in-space operations and optimized in-space vehicle propulsion system operability.

  15. Preliminary Design of Monitoring and Control Subsystem for GNSS Ground Station

    Directory of Open Access Journals (Sweden)

    Seongkyun Jeong

    2008-06-01

    Full Text Available GNSS (Global Navigation Satellite System Ground Station monitors navigation satellite signal, analyzes navigation result, and uploads correction information to satellite. GNSS Ground Station is considered as a main object for constructing GNSS infra-structure and applied in various fields. ETRI (Electronics and Telecommunications Research Institute is developing Monitoring and Control subsystem, which is subsystem of GNSS Ground Station. Monitoring and Control subsystem acquires GPS and Galileo satellite signal and provides signal monitoring data to GNSS control center. In this paper, the configurations of GNSS Ground Station and Monitoring and Control subsystem are introduced and the preliminary design of Monitoring and Control subsystem is performed. Monitoring and Control subsystem consists of data acquisition module, data formatting and archiving module, data error correction module, navigation solution determination module, independent quality monitoring module, and system operation and maintenance module. The design process uses UML (Unified Modeling Language method which is a standard for developing software and consists of use-case modeling, domain design, software structure design, and user interface structure design. The preliminary design of Monitoring and Control subsystem enhances operation capability of GNSS Ground Station and is used as basic material for detail design of Monitoring and Control subsystem.

  16. Subsystem for processing, storage and editing of the results of the chamber film scanning

    International Nuclear Information System (INIS)

    Balgansurehn, Ya.; Dirner, A.; Ivanov, V.G.

    1987-01-01

    A subsystem which is an element of the high-automated system for film data processing and intended for run with the scanning information is described. The subsystem consists of routines which allow to create, to edit and to print the file of scanning results both in batch and interactive mode on the CDC-6500 computer

  17. Approaches and Tools Used to Teach the Computer Input/Output Subsystem: A Survey

    Science.gov (United States)

    Larraza-Mendiluze, Edurne; Garay-Vitoria, Nestor

    2015-01-01

    This paper surveys how the computer input/output (I/O) subsystem is taught in introductory undergraduate courses. It is important to study the educational process of the computer I/O subsystem because, in the curricula recommendations, it is considered a core topic in the area of knowledge of computer architecture and organization (CAO). It is…

  18. Development and testing of the data automation subsystem for the Mariner Mars 1971 spacecraft

    Science.gov (United States)

    1971-01-01

    The data automation subsystem designed and built as part of the Mariner Mars 1971 program, sequences and controls the science instruments and formats all science data. A description of the subsystem with emphasis on major changes relative to Mariner Mars 1969 is presented. In addition, the complete test phase is described.

  19. THE INFLUENCE OF AGRIBUSINESS SUBSYSTEM ON BEEF CATTLE FATTENING FARMS PROFIT IN CENTRAL JAVA

    Directory of Open Access Journals (Sweden)

    E. Rianto

    2012-06-01

    Full Text Available This study was aimed : (i to know the subsystem implementation and agribusiness planning in beef cattle fattening; (ii to count the profit of beef cattle farming; (iii to analyze the effect of agribusiness subsystem implementation and agribusiness planning to beef cattle fattening profit. This study was carried out using survey method and the elementary units were feedlot farmers. The sample was determined by Purposive Quota Sampling Method on 112 respondents spread across five regencies, namely Blora, Rembang, Grobogan, Wonogiri, and Boyolali. Data were collected from primary and secondary sources. The data analysis used quantitative descriptive and inferential statistics method, which include scoring, financial, and multiple linear regression analysis. The results showed that : (i the implementation of agribusiness subsystem (including preproduction subsystem, marketing, and agribusiness support services and agribusiness planning were not so good category, while the cattle farming subsystem was moderate category; (ii the average of farming scale in each feedlot farmer was 2.95 head of cattle with the profit rate was IDR 1,044,719 per fattening period during 6.68 months (equivalent to IDR 156,395 per month; (iii agribusiness subsystem and agribusiness planning had significant impact on feedlot farmer profit simultaneously, but preproduction subsystem and the agribusiness support services subsystem partially had a significant impact on feedlot farmer profit.

  20. THE INFLUENCE OF AGRIBUSINESS SUBSYSTEM ON BEEF CATTLE FATTENING FARM’S PROFIT IN CENTRAL JAVA

    Directory of Open Access Journals (Sweden)

    E. Prasetyo

    2014-10-01

    Full Text Available This study was aimed : (i to know the subsystem implementation and agribusiness planning inbeef cattle fattening; (ii to count the profit of beef cattle farming; (iii to analyze the effect ofagribusiness subsystem implementation and agribusiness planning to beef cattle fattening profit. Thisstudy was carried out using survey method and the elementary units were feedlot farmers. The samplewas determined by Purposive Quota Sampling Method on 112 respondents spread across five regencies,namely Blora, Rembang, Grobogan, Wonogiri, and Boyolali. Data were collected from primary andsecondary sources. The data analysis used quantitative descriptive and inferential statistics method,which include scoring, financial, and multiple linear regression analysis. The results showed that : (i theimplementation of agribusiness subsystem (including preproduction subsystem, marketing, andagribusiness support services and agribusiness planning were not so good category, while the cattlefarming subsystem was moderate category; (ii the average of farming scale in each feedlot farmer was2.95 head of cattle with the profit rate was IDR 1,044,719 per fattening period during 6.68 months(equivalent to IDR 156,395 per month; (iii agribusiness subsystem and agribusiness planning hadsignificant impact on feedlot farmer profit simultaneously, but preproduction subsystem and theagribusiness support services subsystem partially had a significant impact on feedlot farmer profit.

  1. BEHAVE: fire behavior prediction and fuel modeling system-BURN Subsystem, part 1

    Science.gov (United States)

    Patricia L. Andrews

    1986-01-01

    Describes BURN Subsystem, Part 1, the operational fire behavior prediction subsystem of the BEHAVE fire behavior prediction and fuel modeling system. The manual covers operation of the computer program, assumptions of the mathematical models used in the calculations, and application of the predictions.

  2. A new generation of high performance engines for spacecraft propulsion

    Science.gov (United States)

    Rosenberg, Sanders D.; Schoenman, Leonard

    1991-01-01

    Experimental data validating advanced engine designs at three thrust levels (5, 15, and 100 lbF) is presented. All of the three engine designs considered employ a Moog bipropellant torque motor valve, platelet injector design, and iridium-lined rhenium combustion chamber. Attention is focused on the performance, robustness, duration, and flexibility characteristics of the engines. It is noted that the 5- and 15-lbF thrust engines can deliver a steady state specific impulse in excess of 310 lbF-sec/lbm at an area ratio of 150:1, while the 150-lbF thrust engines deliver a steady state specific impulse of 320 lbF-sec/lbm at an area ratio of 250:1. The hot-fire test results reveal specific impulse improvements of 15 to 25 sec over conventional fuel film cooled columbium chamber designs while operating at maximum chamber temperatures.

  3. [Financing, organization, costs and services performance of the Argentinean health sub-systems.

    Science.gov (United States)

    Yavich, Natalia; Báscolo, Ernesto Pablo; Haggerty, Jeannie

    2016-01-01

    To analyze the relationship between health system financing and services organization models with costs and health services performance in each of Rosario's health sub-systems. The financing and organization models were characterized using secondary data. Costs were calculated using the WHO/SHA methodology. Healthcare quality was measured by a household survey (n=822). Public subsystem:Vertically integrated funding and primary healthcare as a leading strategy to provide services produced low costs and individual-oriented healthcare but with weak accessibility conditions and comprehensiveness. Private subsystem: Contractual integration and weak regulatory and coordination mechanisms produced effects opposed to those of the public sub-system. Social security: Contractual integration and strong regulatory and coordination mechanisms contributed to intermediate costs and overall high performance. Each subsystem financing and services organization model had a strong and heterogeneous influence on costs and health services performance.

  4. Independent operation by subsystems: Strategic behavior for the Brazilian electricity sector

    International Nuclear Information System (INIS)

    Guido Tapia Carpio, Lucio; Olimpio Pereira, Amaro

    2006-01-01

    This article describes the competitive strategies of the subsystems in the Brazilian electricity sector. The objective is to present a model in which the operation of each subsystem is managed independently. As the subsystems correspond to the country's geographic regions, the adoption of this model creates conditions for each region to develop according to its own peculiarities. The decision-making process is described based Game Theory. As such, the players or operators of each subsystem carry out their strategies based on the quantities produced, which results in Nash-Cournot equilibrium. In this model, the importance of the proper transmission line dimensioning is highlighted. It determines the competition level among subsystems and allows for optimization of the whole system without requiring arrangements for managing the congestion of the energy transportation grid. The model was programmed in FORTRAN, using IBM's optimization subroutine library (OSL) package

  5. Preliminary analysis of a membrane-based atmosphere-control subsystem

    Science.gov (United States)

    Mccray, Scott B.; Newbold, David D.; Ray, Rod; Ogle, Kathryn

    1993-01-01

    Controlled ecological life supprot systems will require subsystems for maintaining the consentrations of atmospheric gases within acceptable ranges in human habitat chambers and plant growth chambers. The goal of this work was to develop a membrane-based atmosphere comntrol (MBAC) subsystem that allows the controlled exchange of atmospheric componets (e.g., oxygen, carbon dioxide, and water vapor) between these chambers. The MBAC subsystem promises to offer a simple, nonenergy intensive method to separate, store and exchange atmospheric components, producing optimal concentrations of components in each chamber. In this paper, the results of a preliminary analysis of the MBAC subsystem for control of oxygen and nitrogen are presented. Additionally, the MBAC subsystem and its operation are described.

  6. An overview of the NASA Advanced Propulsion Concepts program

    International Nuclear Information System (INIS)

    Curran, F.M.; Bennett, G.L.; Frisbee, R.H.; Sercel, J.C.; Lapointe, M.R.

    1992-07-01

    NASA Advanced Propulsion Concepts (APC) program for the development of long-term space propulsion system schemes is managed by both NASA-Lewis and the JPL and is tasked with the identification and conceptual development of high-risk/high-payoff configurations. Both theoretical and experimental investigations have been undertaken in technology areas deemed essential to the implementation of candidate concepts. These APC candidates encompass very high energy density chemical propulsion systems, advanced electric propulsion systems, and an antiproton-catalyzed nuclear propulsion concept. A development status evaluation is presented for these systems. 45 refs

  7. Optimal allocation of thermodynamic irreversibility for the integrated design of propulsion and thermal management systems

    Science.gov (United States)

    Maser, Adam Charles

    More electric aircraft systems, high power avionics, and a reduction in heat sink capacity have placed a larger emphasis on correctly satisfying aircraft thermal management requirements during conceptual design. Thermal management systems must be capable of dealing with these rising heat loads, while simultaneously meeting mission performance. Since all subsystem power and cooling requirements are ultimately traced back to the engine, the growing interactions between the propulsion and thermal management systems are becoming more significant. As a result, it is necessary to consider their integrated performance during the conceptual design of the aircraft gas turbine engine cycle to ensure that thermal requirements are met. This can be accomplished by using thermodynamic subsystem modeling and simulation while conducting the necessary design trades to establish the engine cycle. However, this approach also poses technical challenges associated with the existence of elaborate aircraft subsystem interactions. This research addresses these challenges through the creation of a parsimonious, transparent thermodynamic model of propulsion and thermal management systems performance with a focus on capturing the physics that have the largest impact on propulsion design choices. This modeling environment, known as Cycle Refinement for Aircraft Thermodynamically Optimized Subsystems (CRATOS), is capable of operating in on-design (parametric) and off-design (performance) modes and includes a system-level solver to enforce design constraints. A key aspect of this approach is the incorporation of physics-based formulations involving the concurrent usage of the first and second laws of thermodynamics, which are necessary to achieve a clearer view of the component-level losses across the propulsion and thermal management systems. This is facilitated by the direct prediction of the exergy destruction distribution throughout the system and the resulting quantification of available

  8. Default Mode Network Subsystems are Differentially Disrupted in Posttraumatic Stress Disorder.

    Science.gov (United States)

    Miller, Danielle R; Hayes, Scott M; Hayes, Jasmeet P; Spielberg, Jeffrey M; Lafleche, Ginette; Verfaellie, Mieke

    2017-05-01

    Posttraumatic stress disorder (PTSD) is a psychiatric disorder characterized by debilitating re-experiencing, avoidance, and hyperarousal symptoms following trauma exposure. Recent evidence suggests that individuals with PTSD show disrupted functional connectivity in the default mode network, an intrinsic network that consists of a midline core, a medial temporal lobe (MTL) subsystem, and a dorsomedial prefrontal cortex (dMPFC) subsystem. The present study examined whether functional connectivity in these subsystems is differentially disrupted in PTSD. Sixty-nine returning war Veterans with PTSD and 44 trauma-exposed Veterans without PTSD underwent resting state functional MRI (rs-fMRI). To examine functional connectivity, seeds were placed in the core hubs of the default mode network, namely the posterior cingulate cortex (PCC) and anterior medial PFC (aMPFC), and in each subsystem. Compared to controls, individuals with PTSD had reduced functional connectivity between the PCC and the hippocampus, a region of the MTL subsystem. Groups did not differ in connectivity between the PCC and dMPFC subsystem or between the aMPFC and any region within either subsystem. In the PTSD group, connectivity between the PCC and hippocampus was negatively associated with avoidance/numbing symptoms. Examination of the MTL and dMPFC subsystems revealed reduced anticorrelation between the ventromedial PFC (vMPFC) seed of the MTL subsystem and the dorsal anterior cingulate cortex in the PTSD group. Our results suggest that selective alterations in functional connectivity in the MTL subsystem of the default mode network in PTSD may be an important factor in PTSD pathology and symptomatology.

  9. Advanced Space Suit Portable Life Support Subsystem Packaging Design

    Science.gov (United States)

    Howe, Robert; Diep, Chuong; Barnett, Bob; Thomas, Gretchen; Rouen, Michael; Kobus, Jack

    2006-01-01

    This paper discusses the Portable Life Support Subsystem (PLSS) packaging design work done by the NASA and Hamilton Sundstrand in support of the 3 future space missions; Lunar, Mars and zero-g. The goal is to seek ways to reduce the weight of PLSS packaging, and at the same time, develop a packaging scheme that would make PLSS technology changes less costly than the current packaging methods. This study builds on the results of NASA s in-house 1998 study, which resulted in the "Flex PLSS" concept. For this study the present EMU schematic (low earth orbit) was used so that the work team could concentrate on the packaging. The Flex PLSS packaging is required to: protect, connect, and hold the PLSS and its components together internally and externally while providing access to PLSS components internally for maintenance and for technology change without extensive redesign impact. The goal of this study was two fold: 1. Bring the advanced space suit integrated Flex PLSS concept from its current state of development to a preliminary design level and build a proof of concept mockup of the proposed design, and; 2. "Design" a Design Process, which accommodates both the initial Flex PLSS design and the package modifications, required to accommodate new technology.

  10. Upgrade of ESO's FIERA CCD Controller and PULPO Subsystem

    Science.gov (United States)

    Reyes-Moreno, J.; Geimer, C.; Balestra, A.; Haddad, N.

    An overview of FIERA is presented with emphasis on its recent upgrade to PCI. The PCI board hosts two DSPs, one for real time control of the camera and another for on-the-fly processing of the incoming video data. In addition, the board is able to make DMA transfers, to synchronize to other boards alike, to be synchronized by a TIM bus and to control PULPO via RS232. The design is based on the IOP480 chip from PLX, for which we have developed a device driver for both Solaris and Linux. One computer is able to host more than one board and therefore can control an array of FIERA detector electronics. PULPO is a multifunctional subsystem widely used at ESO for the housekeeping of CCD cryostat heads and for shutter control. The upgrade of PULPO is based on an embedded PC running Linux. The upgraded PULPO is able to handle 29 temperature sensors, control 8 heaters and one shutter, read out one vacuum sensor and log any combination of parameters.

  11. The magnetic diagnostics subsystem of the LISA Technology Package

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Aguilo, M; Garcia-Berro, E [Departament de Fisica Aplicada, Universitat Politecnica de Catalunya, c/Esteve Terrades, 5, 08860 Castelldefels (Spain); Lobo, A; Mateos, N; Sanjuan, J, E-mail: marc.diaz.aguilo@fa.upc.ed [Institut d' Estudis Espacials de Catalunya, c/Gran Capita 2-4, Edif. Nexus 104, 08034 Barcelona (Spain)

    2010-05-01

    The Magnetic Diagnostics Subsystem of the LISA Technology Package (LTP) on board the LISA Pathfinder (LPF) spacecraft includes a set of four tri-axial fluxgate magnetometers, intended to measure with high precision the magnetic field at the positions they occupy. However, their readouts do not provide a direct measurement of the magnetic field at the positions of the test masses. Therefore, an interpolation method must be implemented to obtain this information. However, such interpolation process faces serious difficulties. Indeed, the size of the interpolation region is excessive for a linear interpolation to be reliable, and the number of magnetometer channels does not provide sufficient data to go beyond that poor approximation. Recent research points to a possible alternative to address the magnetic interpolation problem by means of neural network algorithms. The key point of this approach is the ability neural networks have to learn from suitable training data representing the magnetic field behaviour. Despite the large distance to the test masses and the insufficient magnetic readings, artificial neural networks are able to significantly reduce the estimation error to acceptable levels. The learning efficiency can be best improved by making use of data obtained from on-ground measurements prior to mission launch in all relevant satellite locations and under real operation conditions. Reliable information on that appears to be essential for a meaningful assessment of magnetic noise in the LTP.

  12. The magnetic diagnostics subsystem of the LISA Technology Package

    International Nuclear Information System (INIS)

    Diaz-Aguilo, M; Garcia-Berro, E; Lobo, A; Mateos, N; Sanjuan, J

    2010-01-01

    The Magnetic Diagnostics Subsystem of the LISA Technology Package (LTP) on board the LISA Pathfinder (LPF) spacecraft includes a set of four tri-axial fluxgate magnetometers, intended to measure with high precision the magnetic field at the positions they occupy. However, their readouts do not provide a direct measurement of the magnetic field at the positions of the test masses. Therefore, an interpolation method must be implemented to obtain this information. However, such interpolation process faces serious difficulties. Indeed, the size of the interpolation region is excessive for a linear interpolation to be reliable, and the number of magnetometer channels does not provide sufficient data to go beyond that poor approximation. Recent research points to a possible alternative to address the magnetic interpolation problem by means of neural network algorithms. The key point of this approach is the ability neural networks have to learn from suitable training data representing the magnetic field behaviour. Despite the large distance to the test masses and the insufficient magnetic readings, artificial neural networks are able to significantly reduce the estimation error to acceptable levels. The learning efficiency can be best improved by making use of data obtained from on-ground measurements prior to mission launch in all relevant satellite locations and under real operation conditions. Reliable information on that appears to be essential for a meaningful assessment of magnetic noise in the LTP.

  13. Separate valuation subsystems for delay and effort decision costs.

    Science.gov (United States)

    Prévost, Charlotte; Pessiglione, Mathias; Météreau, Elise; Cléry-Melin, Marie-Laure; Dreher, Jean-Claude

    2010-10-20

    Decision making consists of choosing among available options on the basis of a valuation of their potential costs and benefits. Most theoretical models of decision making in behavioral economics, psychology, and computer science propose that the desirability of outcomes expected from alternative options can be quantified by utility functions. These utility functions allow a decision maker to assign subjective values to each option under consideration by weighting the likely benefits and costs resulting from an action and to select the one with the highest subjective value. Here, we used model-based neuroimaging to test whether the human brain uses separate valuation systems for rewards (erotic stimuli) associated with different types of costs, namely, delay and effort. We show that humans devalue rewards associated with physical effort in a strikingly similar fashion to those they devalue that are associated with delays, and that a single computational model derived from economics theory can account for the behavior observed in both delay discounting and effort discounting. However, our neuroimaging data reveal that the human brain uses distinct valuation subsystems for different types of costs, reflecting in opposite fashion delayed reward and future energetic expenses. The ventral striatum and the ventromedial prefrontal cortex represent the increasing subjective value of delayed rewards, whereas a distinct network, composed of the anterior cingulate cortex and the anterior insula, represent the decreasing value of the effortful option, coding the expected expense of energy. Together, these data demonstrate that the valuation processes underlying different types of costs can be fractionated at the cerebral level.

  14. VERIFICATION OF THE SENTINEL-4 FOCAL PLANE SUBSYSTEM

    Directory of Open Access Journals (Sweden)

    C. Williges

    2017-05-01

    Full Text Available The Sentinel-4 payload is a multi-spectral camera system which is designed to monitor atmospheric conditions over Europe. The German Aerospace Center (DLR in Berlin, Germany conducted the verification campaign of the Focal Plane Subsystem (FPS on behalf of Airbus Defense and Space GmbH, Ottobrunn, Germany. The FPS consists, inter alia, of two Focal Plane Assemblies (FPAs, one for the UV-VIS spectral range (305 nm … 500 nm, the second for NIR (750 nm … 775 nm. In this publication, we will present in detail the opto-mechanical laboratory set-up of the verification campaign of the Sentinel-4 Qualification Model (QM which will also be used for the upcoming Flight Model (FM verification. The test campaign consists mainly of radiometric tests performed with an integrating sphere as homogenous light source. The FPAs have mainly to be operated at 215 K ± 5 K, making it necessary to exploit a thermal vacuum chamber (TVC for the test accomplishment. This publication focuses on the challenge to remotely illuminate both Sentinel-4 detectors as well as a reference detector homogeneously over a distance of approximately 1 m from outside the TVC. Furthermore selected test analyses and results will be presented, showing that the Sentinel-4 FPS meets specifications.

  15. Anatomy, histochemistry and immunohistochemistry of the olfactory subsystems in mice

    Directory of Open Access Journals (Sweden)

    Arthur William Barrios

    2014-07-01

    Full Text Available The four regions of the murine nasal cavity featuring olfactory neurons were studied anatomically and by labelling with lectins and relevant antibodies with a view to establishing criteria for the identification of olfactory subsystems that are readily applicable to other mammals. In the main olfactory epithelium and the septal organ the olfactory sensory neurons (OSNs are embedded in quasi-stratified columnar epithelium; vomeronasal OSNs are embedded in epithelium lining the medial interior wall of the vomeronasal duct and do not make contact with the mucosa of the main nasal cavity; and in Grüneberg’s ganglion a small isolated population of OSNs lies adjacent to, but not within, the epithelium. With the exception of Grüneberg’s ganglion, all the tissues expressing olfactory marker protein (OMP (the above four nasal territories, the vomeronasal and main olfactory nerves, and the main and accessory olfactory bulbs are also labelled by Lycopersicum esculentum agglutinin, while Ulex europaeus agglutinin I labels all and only tissues expressing Gi2 (the apical sensory neurons of the vomeronasal organ, their axons, and their glomerular destinations in the anterior accessory olfactory bulb. These staining patterns of UEA-I and LEA may facilitate the characterization of olfactory anatomy in other species. A 710-section atlas of the anatomy of the murine nasal cavity has been made available on line.

  16. Quantum trajectory analysis of multimode subsystem-bath dynamics.

    Science.gov (United States)

    Wyatt, Robert E; Na, Kyungsun

    2002-01-01

    The dynamics of a swarm of quantum trajectories is investigated for systems involving the interaction of an active mode (the subsystem) with an M-mode harmonic reservoir (the bath). Equations of motion for the position, velocity, and action function for elements of the probability fluid are integrated in the Lagrangian (moving with the fluid) picture of quantum hydrodynamics. These fluid elements are coupled through the Bohm quantum potential and as a result evolve as a correlated ensemble. Wave function synthesis along the trajectories permits an exact description of the quantum dynamics for the evolving probability fluid. The approach is fully quantum mechanical and does not involve classical or semiclassical approximations. Computational results are presented for three systems involving the interaction on an active mode with M=1, 10, and 15 bath modes. These results include configuration space trajectory evolution, flux analysis of the evolving ensemble, wave function synthesis along trajectories, and energy partitioning along specific trajectories. These results demonstrate the feasibility of using a small number of quantum trajectories to obtain accurate quantum results on some types of open quantum systems that are not amenable to standard quantum approaches involving basis set expansions or Eulerian space-fixed grids.

  17. Gauge subsystems, separability and robustness in autonomous quantum memories

    International Nuclear Information System (INIS)

    Sarma, Gopal; Mabuchi, Hideo

    2013-01-01

    Quantum error correction provides a fertile context for exploring the interplay of feedback control, microscopic physics and non-commutative probability. In this paper we deepen our understanding of this nexus through high-level analysis of a class of quantum memory models that we have previously proposed, which implement continuous-time versions of well-known stabilizer codes in autonomous nanophotonic circuits that require no external clocking or control. We demonstrate that the presence of the gauge subsystem in the nine-qubit Bacon–Shor code allows for a loss-tolerant layout of the corresponding nanophotonic circuit that substantially ameliorates the effects of optical propagation losses, argue that code separability allows for simplified restoration feedback protocols, and propose a modified fidelity metric for quantifying the performance of realistic quantum memories. Our treatment of these topics exploits the homogeneous modeling framework of autonomous nanophotonic circuits, but the key ideas translate to the traditional setting of discrete time, measurement-based quantum error correction. (paper)

  18. Verification of the Sentinel-4 focal plane subsystem

    Science.gov (United States)

    Williges, Christian; Uhlig, Mathias; Hilbert, Stefan; Rossmann, Hannes; Buchwinkler, Kevin; Babben, Steffen; Sebastian, Ilse; Hohn, Rüdiger; Reulke, Ralf

    2017-09-01

    The Sentinel-4 payload is a multi-spectral camera system, designed to monitor atmospheric conditions over Europe from a geostationary orbit. The German Aerospace Center, DLR Berlin, conducted the verification campaign of the Focal Plane Subsystem (FPS) during the second half of 2016. The FPS consists, of two Focal Plane Assemblies (FPAs), two Front End Electronics (FEEs), one Front End Support Electronic (FSE) and one Instrument Control Unit (ICU). The FPAs are designed for two spectral ranges: UV-VIS (305 nm - 500 nm) and NIR (750 nm - 775 nm). In this publication, we will present in detail the set-up of the verification campaign of the Sentinel-4 Qualification Model (QM). This set up will also be used for the upcoming Flight Model (FM) verification, planned for early 2018. The FPAs have to be operated at 215 K +/- 5 K, making it necessary to exploit a thermal vacuum chamber (TVC) for the test accomplishment. The test campaign consists mainly of radiometric tests. This publication focuses on the challenge to remotely illuminate both Sentinel-4 detectors as well as a reference detector homogeneously over a distance of approximately 1 m from outside the TVC. Selected test analyses and results will be presented.

  19. Performance overview of the Euclid infrared focal plane detector subsystems

    Science.gov (United States)

    Waczynski, A.; Barbier, R.; Cagiano, S.; Chen, J.; Cheung, S.; Cho, H.; Cillis, A.; Clémens, J.-C.; Dawson, O.; Delo, G.; Farris, M.; Feizi, A.; Foltz, R.; Hickey, M.; Holmes, W.; Hwang, T.; Israelsson, U.; Jhabvala, M.; Kahle, D.; Kan, Em.; Kan, Er.; Loose, M.; Lotkin, G.; Miko, L.; Nguyen, L.; Piquette, E.; Powers, T.; Pravdo, S.; Runkle, A.; Seiffert, M.; Strada, P.; Tucker, C.; Turck, K.; Wang, F.; Weber, C.; Williams, J.

    2016-07-01

    In support of the European space agency (ESA) Euclid mission, NASA is responsible for the evaluation of the H2RG mercury cadmium telluride (MCT) detectors and electronics assemblies fabricated by Teledyne imaging systems. The detector evaluation is performed in the detector characterization laboratory (DCL) at the NASA Goddard space flight center (GSFC) in close collaboration with engineers and scientists from the jet propulsion laboratory (JPL) and the Euclid project. The Euclid near infrared spectrometer and imaging photometer (NISP) will perform large area optical and spectroscopic sky surveys in the 0.9-2.02 μm infrared (IR) region. The NISP instrument will contain sixteen detector arrays each coupled to a Teledyne SIDECAR application specific integrated circuit (ASIC). The focal plane will operate at 100K and the SIDECAR ASIC will be in close proximity operating at a slightly higher temperature of 137K. This paper will describe the test configuration, performance tests and results of the latest engineering run, also known as pilot run 3 (PR3), consisting of four H2RG detectors operating simultaneously. Performance data will be presented on; noise, spectral quantum efficiency, dark current, persistence, pixel yield, pixel to pixel uniformity, linearity, inter pixel crosstalk, full well and dynamic range, power dissipation, thermal response and unit cell input sensitivity.

  20. Improved Dynamic Modeling of the Cascade Distillation Subsystem and Integration with Models of Other Water Recovery Subsystems

    Science.gov (United States)

    Perry, Bruce; Anderson, Molly

    2015-01-01

    The Cascade Distillation Subsystem (CDS) is a rotary multistage distiller being developed to serve as the primary processor for wastewater recovery during long-duration space missions. The CDS could be integrated with a system similar to the International Space Station (ISS) Water Processor Assembly (WPA) to form a complete Water Recovery System (WRS) for future missions. Independent chemical process simulations with varying levels of detail have previously been developed using Aspen Custom Modeler (ACM) to aid in the analysis of the CDS and several WPA components. The existing CDS simulation could not model behavior during thermal startup and lacked detailed analysis of several key internal processes, including heat transfer between stages. The first part of this paper describes modifications to the ACM model of the CDS that improve its capabilities and the accuracy of its predictions. Notably, the modified version of the model can accurately predict behavior during thermal startup for both NaCl solution and pretreated urine feeds. The model is used to predict how changing operating parameters and design features of the CDS affects its performance, and conclusions from these predictions are discussed. The second part of this paper describes the integration of the modified CDS model and the existing WPA component models into a single WRS model. The integrated model is used to demonstrate the effects that changes to one component can have on the dynamic behavior of the system as a whole.

  1. Interplanetary space transport using inertial fusion propulsion

    International Nuclear Information System (INIS)

    Orth, C.D.

    1998-01-01

    In this paper, we indicate how the great advantages that ICF offers for interplanetary propulsion can be accomplished with the VISTA spacecraft concept. The performance of VISTA is expected to surpass that from other realistic technologies for Mars missions if the energy gain achievable for ICF targets is above several hundred. Based on the good performance expected from the U. S. National Ignition Facility (NIF), the requirements for VISTA should be well within the realm of possibility if creative target concepts such as the fast ignitor can be developed. We also indicate that a 6000-ton VISTA can visit any planet in the solar system and return to Earth in about 7 years or less without any significant physiological hazards to astronauts. In concept, VISTA provides such short-duration missions, especially to Mars, that the hazards from cosmic radiation and zero gravity can be reduced to insignificant levels. VISTA therefore represents a significant step forward for space-propulsion concepts

  2. Evolutionary use of nuclear electric propulsion

    International Nuclear Information System (INIS)

    Hack, K.J.; George, J.A.; Riehl, J.P.; Gilland, J.H.

    1990-01-01

    Evolving new propulsion technologies through a rational and conscious effort to minimize development costs and program risks while maximizing the performance benefits is intuitively practical. A phased approach to the evolution of nuclear electric propulsion from use on planetary probes, to lunar cargo vehicles, and finally to manned Mars missions with a concomitant growth in technology is considered. Technology levels and system component makeup are discussed for nuclear power systems and both ion and magnetoplasmadynamic thrusters. Mission scenarios are described, which include analysis of a probe to Pluto, a lunar cargo mission, Martian split, all-up, and quick-trip mission options. Evolutionary progression of the use of NEP in such missions is discussed. 26 refs

  3. Waves from Propulsion Systems of Fast Ferries

    DEFF Research Database (Denmark)

    Taatø, Søren Haugsted; Aage, Christian; Arnskov, Michael M.

    1998-01-01

    Waves from fast ferries have become an environmental problem of growing concern to the public. Fast ferries produce not only higher waves than conventional ships but also fundamentally different wave systems when they sail at supercritical speeds. Hitherto, ship waves have been considered as being...... generated by the ship hulls alone. Whereas this assumption may be reasonable for conventional ships with large hulls and limited propulsive power, the situation is different for fast ferries with their smaller hulls and very large installed power. A simple theoretical model and a series of model tests...... on a monohull fast ferry seem to indicate that a substantial part of the wave-making can be directly attributed to the propulsion system itself. Thus, two wave systems are created with different phases, but with similar frequency contents, which means that they merge into one system behind the ship, very...

  4. Optimization analysis of propulsion motor control efficiency

    Directory of Open Access Journals (Sweden)

    CAI Qingnan

    2017-12-01

    Full Text Available [Objectives] This paper aims to strengthen the control effect of propulsion motors and decrease the energy used during actual control procedures.[Methods] Based on the traditional propulsion motor equivalence circuit, we increase the iron loss current component, introduce the definition of power matching ratio, calculate the highest efficiency of a motor at a given speed and discuss the flux corresponding to the power matching ratio with the highest efficiency. In the original motor vector efficiency optimization control module, an efficiency optimization control module is added so as to achieve motor efficiency optimization and energy conservation.[Results] MATLAB/Simulink simulation data shows that the efficiency optimization control method is suitable for most conditions. The operation efficiency of the improved motor model is significantly higher than that of the original motor model, and its dynamic performance is good.[Conclusions] Our motor efficiency optimization control method can be applied in engineering to achieve energy conservation.

  5. Hypersonic Vehicle Propulsion System Simplified Model Development

    Science.gov (United States)

    Stueber, Thomas J.; Raitano, Paul; Le, Dzu K.; Ouzts, Peter

    2007-01-01

    This document addresses the modeling task plan for the hypersonic GN&C GRC team members. The overall propulsion system modeling task plan is a multi-step process and the task plan identified in this document addresses the first steps (short term modeling goals). The procedures and tools produced from this effort will be useful for creating simplified dynamic models applicable to a hypersonic vehicle propulsion system. The document continues with the GRC short term modeling goal. Next, a general description of the desired simplified model is presented along with simulations that are available to varying degrees. The simulations may be available in electronic form (FORTRAN, CFD, MatLab,...) or in paper form in published documents. Finally, roadmaps outlining possible avenues towards realizing simplified model are presented.

  6. Propulsion Mechanism of Catalytic Microjet Engines.

    Science.gov (United States)

    Fomin, Vladimir M; Hippler, Markus; Magdanz, Veronika; Soler, Lluís; Sanchez, Samuel; Schmidt, Oliver G

    2014-02-01

    We describe the propulsion mechanism of the catalytic microjet engines that are fabricated using rolled-up nanotech. Microjets have recently shown numerous potential applications in nanorobotics but currently there is a lack of an accurate theoretical model that describes the origin of the motion as well as the mechanism of self-propulsion. The geometric asymmetry of a tubular microjet leads to the development of a capillary force, which tends to propel a bubble toward the larger opening of the tube. Because of this motion in an asymmetric tube, there emerges a momentum transfer to the fluid. In order to compensate this momentum transfer, a jet force acting on the tube occurs. This force, which is counterbalanced by the linear drag force, enables tube velocities of the order of 100 μ m/s. This mechanism provides a fundamental explanation for the development of driving forces that are acting on bubbles in tubular microjets.

  7. ac propulsion system for an electric vehicle

    Science.gov (United States)

    Geppert, S.

    1980-01-01

    It is pointed out that dc drives will be the logical choice for current production electric vehicles (EV). However, by the mid-80's, there is a good chance that the price and reliability of suitable high-power semiconductors will allow for a competitive ac system. The driving force behind the ac approach is the induction motor, which has specific advantages relative to a dc shunt or series traction motor. These advantages would be an important factor in the case of a vehicle for which low maintenance characteristics are of primary importance. A description of an EV ac propulsion system is provided, taking into account the logic controller, the inverter, the motor, and a two-speed transmission-differential-axle assembly. The main barrier to the employment of the considered propulsion system in EV is not any technical problem, but inverter transistor cost.

  8. Ultra-high temperature direct propulsion

    International Nuclear Information System (INIS)

    Araj, K.J.; Slovik, G.; Powell, J.R.; Ludewig, H.

    1987-01-01

    Potential advantages of ultra-high exhaust temperature (3000 K - 4000 K) direct propulsion nuclear rockets are explored. Modifications to the Particle Bed Reactor (PBR) to achieve these temperatures are described. Benefits of ultra-high temperature propulsion are discussed for two missions - orbit transfer (ΔV = 5546 m/s) and interplanetary exploration (ΔV = 20000 m/s). For such missions ultra-high temperatures appear to be worth the additional complexity. Thrust levels are reduced substantially for a given power level, due to the higher enthalpy caused by partial disassociation of the hydrogen propellant. Though technically challenging, it appears potentially feasible to achieve such ultra high temperatures using the PBR

  9. 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.

  10. NASA's progress in nuclear electric propulsion technology

    International Nuclear Information System (INIS)

    Stone, J.R.; Doherty, M.P.; Peecook, K.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. 19 refs

  11. Fluidic electrodynamics: Approach to electromagnetic propulsion

    International Nuclear Information System (INIS)

    Martins, Alexandre A.; Pinheiro, Mario J.

    2009-01-01

    We report on a new methodological approach to electrodynamics based on a fluidic viewpoint. We develop a systematic approach establishing analogies between physical magnitudes and isomorphism (structure-preserving mappings) between systems of equations. This methodological approach allows us to give a general expression for the hydromotive force, thus re-obtaining the Navier-Stokes equation departing from the appropriate electromotive force. From this ground we offer a fluidic approach to different kinds of issues with interest in propulsion, e.g., the force exerted by a charged particle on a body carrying current; the magnetic force between two parallel currents; the Magnus's force. It is shown how the intermingle between the fluid vector fields and electromagnetic fields leads to new insights on their dynamics. The new concepts introduced in this work suggest possible applications to electromagnetic (EM) propulsion devices and the mastery of the principles of producing electric fields of required configuration in plasma medium.

  12. A Simple Estimation of Coupling Loss Factors for Two Flexible Subsystems Connected via Discrete Interfaces

    Directory of Open Access Journals (Sweden)

    Jun Zhang

    2016-01-01

    Full Text Available A simple formula is proposed to estimate the Statistical Energy Analysis (SEA coupling loss factors (CLFs for two flexible subsystems connected via discrete interfaces. First, the dynamic interactions between two discretely connected subsystems are described as a set of intermodal coupling stiffness terms. It is then found that if both subsystems are of high modal density and meanwhile the interface points all act independently, the intermodal dynamic couplings become dominated by only those between different subsystem mode sets. If ensemble- and frequency-averaged, the intermodal coupling stiffness terms can simply reduce to a function of the characteristic dynamic properties of each subsystem and the subsystem mass, as well as the number of interface points. The results can thus be accommodated within the theoretical frame of conventional SEA theory to yield a simple CLF formula. Meanwhile, the approach allows the weak coupling region between the two SEA subsystems to be distinguished simply and explicitly. The consistency and difference of the present technique with and from the traditional wave-based SEA solutions are discussed. Finally, numerical examples are given to illustrate the good performance of the present technique.

  13. Amygdala subsystems and control of feeding behavior by learned cues.

    Science.gov (United States)

    Petrovich, Gorica D; Gallagher, Michela

    2003-04-01

    A combination of behavioral studies and a neural systems analysis approach has proven fruitful in defining the role of the amygdala complex and associated circuits in fear conditioning. The evidence presented in this chapter suggests that this approach is also informative in the study of other adaptive functions that involve the amygdala. In this chapter we present a novel model to study learning in an appetitive context. Furthermore, we demonstrate that long-recognized connections between the amygdala and the hypothalamus play a crucial role in allowing learning to modulate feeding behavior. In the first part we describe a behavioral model for motivational learning. In this model a cue that acquires motivational properties through pairings with food delivery when an animal is hungry can override satiety and promote eating in sated rats. Next, we present evidence that a specific amygdala subsystem (basolateral area) is responsible for allowing such learned cues to control eating (override satiety and promote eating in sated rats). We also show that basolateral amygdala mediates these actions via connectivity with the lateral hypothalamus. Lastly, we present evidence that the amygdalohypothalamic system is specific for the control of eating by learned motivational cues, as it does not mediate another function that depends on intact basolateral amygdala, namely, the ability of a conditioned cue to support new learning based on its acquired value. Knowledge about neural systems through which food-associated cues specifically control feeding behavior provides a defined model for the study of learning. In addition, this model may be informative for understanding mechanisms of maladaptive aspects of learned control of eating that contribute to eating disorders and more moderate forms of overeating.

  14. Superconducting Super Collider silicon tracking subsystem research and development

    International Nuclear Information System (INIS)

    Miller, W.O.; Thompson, T.C.; Ziock, H.J.; Gamble, M.T.

    1990-12-01

    The Alamos National Laboratory Mechanical Engineering and Electronics Division has been investigating silicon-based elementary particle tracking device technology as part of the Superconducting Super Collider-sponsored silicon subsystem collaboration. Structural, materials, and thermal issues have been addressed. This paper explores detector structural integrity and stability, including detailed finite element models of the silicon wafer support and predictive methods used in designing with advanced composite materials. The current design comprises a magnesium metal matrix composite (MMC) truss space frame to provide a sparse support structure for the complex array of silicon detectors. This design satisfies the 25-μm structural stability requirement in a 10-Mrad radiation environment. This stability is achieved without exceeding the stringent particle interaction constraints set at 2.5% of a radiation length. Materials studies have considered thermal expansion, elastic modulus, resistance to radiation and chemicals, and manufacturability of numerous candidate materials. Based on optimization of these parameters, the MMC space frame will possess a coefficient of thermal expansion (CTE) near zero to avoid thermally induced distortions, whereas the cooling rings, which support the silicon detectors and heat pipe network, will probably be constructed of a graphite/epoxy composite whose CTE is engineered to match that of silicon. Results from radiation, chemical, and static loading tests are compared with analytical predictions and discussed. Electronic thermal loading and its efficient dissipation using heat pipe cooling technology are discussed. Calculations and preliminary designs for a sprayed-on graphite wick structure are presented. A hydrocarbon such as butane appears to be a superior choice of heat pipe working fluid based on cooling, handling, and safety criteria

  15. MAIUS-1- Vehicle, Subsystems Design and Mission Operations

    Science.gov (United States)

    Stamminger, A.; Ettl, J.; Grosse, J.; Horschgen-Eggers, M.; Jung, W.; Kallenbach, A.; Raith, G.; Saedtler, W.; Seidel, S. T.; Turner, J.; Wittkamp, M.

    2015-09-01

    In November 2015, the DLR Mobile Rocket Base will launch the MAIUS-1 rocket vehicle at Esrange, Northern Sweden. The MAIUS-A experiment is a pathfinder atom optics experiment. The scientific objective of the mission is the first creation of a BoseEinstein Condensate in space and performing atom interferometry on a sounding rocket [3]. MAIUS-1 comprises a two-stage unguided solid propellant VSB-30 rocket motor system. The vehicle consists of a Brazilian 53 1 motor as 1 st stage, a 530 motor as 2nd stage, a conical motor adapter, a despin module, a payload adapter, the MAIUS-A experiment consisting of five experiment modules, an attitude control system module, a newly developed conical service system, and a two-staged recovery system including a nosecone. In contrast to usual payloads on VSB-30 rockets, the payload has a diameter of 500 mm due to constraints of the scientific experiment. Because of this change in design, a blunted nosecone is necessary to guarantee the required static stability during the ascent phase of the flight. This paper will give an overview on the subsystems which have been built at DLR MORABA, especially the newly developed service system. Further, it will contain a description of the MAIUS-1 vehicle, the mission and the unique requirements on operations and attitude control, which is additionally required to achieve a required attitude with respect to the nadir vector. Additionally to a usual microgravity environment, the MAIUS-l payload requires attitude control to achieve a required attitude with respect to the nadir vector.

  16. A new propulsion concept for interplanetary missions

    Science.gov (United States)

    Dujarric, C.

    2001-11-01

    When tons of payload must be brought back from the planets to Earth, the current launch-system technology hits size limitations. The huge Saturn-V launcher that enabled the Apollo missions to go to the Moon would be dwarfed by a single launcher capable of sending men to a destination like Mars and bringing them back. Keeping interplanetary missions within a reasonable size and cost therefore requires technological progress in terms of both vehicle weight reduction and propulsion efficiency.

  17. Application of SDI technology in space propulsion

    International Nuclear Information System (INIS)

    Klein, A.J.

    1992-01-01

    Numerous technologies developed by the DOD within the SDI program are now available for adaptation to the requirements of commercial spacecraft; SDI has accordingly organized the Technology Applications Information System data base, which contains nearly 2000 nonproprietary abstracts on SDI technology. Attention is here given to such illustrative systems as hydrogen arcjets, ammonia arcjets, ion engines, SSTO launch vehicles, gel propellants, lateral thrusters, pulsed electrothermal thrusters, laser-powered rockets, and nuclear propulsion

  18. Propulsion Physics Using the Chameleon Density Model

    Science.gov (United States)

    Robertson, Glen A.

    2011-01-01

    To grow as a space faring race, future spaceflight systems will require a new theory of propulsion. Specifically one that does not require mass ejection without limiting the high thrust necessary to accelerate within or beyond our solar system and return within a normal work period or lifetime. The Chameleon Density Model (CDM) is one such model that could provide new paths in propulsion toward this end. The CDM is based on Chameleon Cosmology a dark matter theory; introduced by Khrouy and Weltman in 2004. Chameleon as it is hidden within known physics, where the Chameleon field represents a scalar field within and about an object; even in the vacuum. The CDM relates to density changes in the Chameleon field, where the density changes are related to matter accelerations within and about an object. These density changes in turn change how an object couples to its environment. Whereby, thrust is achieved by causing a differential in the environmental coupling about an object. As a demonstration to show that the CDM fits within known propulsion physics, this paper uses the model to estimate the thrust from a solid rocket motor. Under the CDM, a solid rocket constitutes a two body system, i.e., the changing density of the rocket and the changing density in the nozzle arising from the accelerated mass. Whereby, the interactions between these systems cause a differential coupling to the local gravity environment of the earth. It is shown that the resulting differential in coupling produces a calculated value for the thrust near equivalent to the conventional thrust model used in Sutton and Ross, Rocket Propulsion Elements. Even though imbedded in the equations are the Universe energy scale factor, the reduced Planck mass and the Planck length, which relates the large Universe scale to the subatomic scale.

  19. Advanced supersonic propulsion study, phase 3

    Science.gov (United States)

    Howlett, R. A.; Johnson, J.; Sabatella, J.; Sewall, T.

    1976-01-01

    The variable stream control engine is determined to be the most promising propulsion system concept for advanced supersonic cruise aircraft. This concept uses variable geometry components and a unique throttle schedule for independent control of two flow streams to provide low jet noise at takeoff and high performance at both subsonic and supersonic cruise. The advanced technology offers a 25% improvement in airplane range and an 8 decibel reduction in takeoff noise, relative to first generation supersonic turbojet engines.

  20. Comparison of Aero-Propulsive Performance Predictions for Distributed Propulsion Configurations

    Science.gov (United States)

    Borer, Nicholas K.; Derlaga, Joseph M.; Deere, Karen A.; Carter, Melissa B.; Viken, Sally A.; Patterson, Michael D.; Litherland, Brandon L.; Stoll, Alex M.

    2017-01-01

    NASA's X-57 "Maxwell" flight demonstrator incorporates distributed electric propulsion technologies in a design that will achieve a significant reduction in energy used in cruise flight. A substantial portion of these energy savings come from beneficial aerodynamic-propulsion interaction. Previous research has shown the benefits of particular instantiations of distributed propulsion, such as the use of wingtip-mounted cruise propellers and leading edge high-lift propellers. However, these benefits have not been reduced to a generalized design or analysis approach suitable for large-scale design exploration. This paper discusses the rapid, "design-order" toolchains developed to investigate the large, complex tradespace of candidate geometries for the X-57. Due to the lack of an appropriate, rigorous set of validation data, the results of these tools were compared to three different computational flow solvers for selected wing and propulsion geometries. The comparisons were conducted using a common input geometry, but otherwise different input grids and, when appropriate, different flow assumptions to bound the comparisons. The results of these studies showed that the X-57 distributed propulsion wing should be able to meet the as-designed performance in cruise flight, while also meeting or exceeding targets for high-lift generation in low-speed flight.