WorldWideScience

Sample records for solid rocket fuel

  1. Development and Characterization of Fast Burning Solid Fuels/Propellants for Hybrid Rocket Motors with High Volumetric Efficiency

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this proposed work is to develop several fast burning solid fuels/fuel-rich solid propellants for hybrid rocket motor applications. In the...

  2. Formulation and Testing of Paraffin-Based Solid Fuels Containing Energetic Additives for Hybrid Rockets

    Science.gov (United States)

    Larson, Daniel B.; Boyer, Eric; Wachs,Trevor; Kuo, Kenneth K.; Story, George

    2012-01-01

    Many approaches have been considered in an effort to improve the regression rate of solid fuels for hybrid rocket applications. One promising method is to use a fuel with a fast burning rate such as paraffin wax; however, additional performance increases to the fuel regression rate are necessary to make the fuel a viable candidate to replace current launch propulsion systems. The addition of energetic and/or nano-sized particles is one way to increase mass-burning rates of the solid fuels and increase the overall performance of the hybrid rocket motor.1,2 Several paraffin-based fuel grains with various energetic additives (e.g., lithium aluminum hydride (LiAlH4) have been cast in an attempt to improve regression rates. There are two major advantages to introducing LiAlH4 additive into the solid fuel matrix: 1) the increased characteristic velocity, 2) decreased dependency of Isp on oxidizer-to-fuel ratio. The testing and characterization of these solid-fuel grains have shown that continued work is necessary to eliminate unburned/unreacted fuel in downstream sections of the test apparatus.3 Changes to the fuel matrix include higher melting point wax and smaller energetic additive particles. The reduction in particle size through various methods can result in more homogeneous grain structure. The higher melting point wax can serve to reduce the melt-layer thickness, allowing the LiAlH4 particles to react closer to the burning surface, thus increasing the heat feedback rate and fuel regression rate. In addition to the formulation of LiAlH4 and paraffin wax solid-fuel grains, liquid additives of triethylaluminum and diisobutylaluminum hydride will be included in this study. Another promising fuel formulation consideration is to incorporate a small percentage of RDX as an additive to paraffin. A novel casting technique will be used by dissolving RDX in a solvent to crystallize the energetic additive. After dissolving the RDX in a solvent chosen for its compatibility

  3. History of Solid Rockets

    Science.gov (United States)

    Green, Rebecca

    2017-01-01

    Solid rockets are of interest to the space program because they are commonly used as boosters that provide the additional thrust needed for the space launch vehicle to escape the gravitational pull of the Earth. Larger, more advanced solid rockets allow for space launch vehicles with larger payload capacities, enabling mankind to reach new depths of space. This presentation will discuss, in detail, the history of solid rockets. The history begins with the invention and origin of the solid rocket, and then goes into the early uses and design of the solid rocket. The evolution of solid rockets is depicted by a description of how solid rockets changed and improved and how they were used throughout the 16th, 17th, 18th, and 19th centuries. Modern uses of the solid rocket include the Solid Rocket Boosters (SRBs) on the Space Shuttle and the solid rockets used on current space launch vehicles. The functions and design of the SRB and the advancements in solid rocket technology since the use of the SRB are discussed as well. Common failure modes and design difficulties are discussed as well.

  4. Optimization of the stand for test of hybrid rocket engines of solid fuel

    Directory of Open Access Journals (Sweden)

    Zolotorev Nikolay

    2017-01-01

    Full Text Available In the paper the laboratory experimental stand of the hybrid rocket engine of solid fuel to study ballistic parameters of the engine at burning of high-energy materials in flow of hot gas is presented. Mixture of air with nitrogen with a specified content of active oxygen is used as a gaseous oxidizer. The experimental stand has modular design and consists of system of gas supply, system of heating of gas, system for monitoring gas parameters, to which a load cell with a model engine was connected. The modular design of the stand allows to change its configuration under specific objective. This experimental stand allows to conduct a wide range of the pilot studies at interaction of a hot stream of gas with samples high-energy materials.

  5. Thiokol Solid Rocket Motors

    Science.gov (United States)

    Graves, S. R.

    2000-01-01

    This paper presents viewgraphs on thiokol solid rocket motors. The topics include: 1) Communications; 2) Military and government intelligence; 3) Positioning satellites; 4) Remote sensing; 5) Space burial; 6) Science; 7) Space manufacturing; 8) Advertising; 9) Space rescue space debris management; 10) Space tourism; 11) Space settlements; 12) Hazardous waste disposal; 13) Extraterrestrial resources; 14) Fast package delivery; and 15) Space utilities.

  6. Study of Liquid Breakup Process in Solid Rocket Motor Nozzle

    Science.gov (United States)

    2016-02-16

    Laboratory, Edwards, CA Abstract In a solid rocket motor (SRM), when the aluminum based propellant combusts, the fuel is oxidized into alumina (Al2O3...34Chemical Erosion of Refractory-Metal Nozzle Inserts in Solid - Propellant Rocket Motors," J. Propulsion and Power, Vol. 25, no.1,, 2009. [4] E. Y. Wong...34 Solid Rocket Nozzle Design Summary," in 4th AIAA Propulsion Joint Specialist Conference, Cleveland, OH, 1968. [5] Nayfeh, A. H.; Saric, W. S

  7. Mechanical and Combustion Performance of Multi-Walled Carbon Nanotubes as an Additive to Paraffin-Based Solid Fuels for Hybrid Rockets

    Science.gov (United States)

    Larson, Daniel B.; Boyer, Eric; Wachs, Trevor; Kuo, Kenneth, K.; Koo, Joseph H.; Story, George

    2012-01-01

    Paraffin-based solid fuels for hybrid rocket motor applications are recognized as a fastburning alternative to other fuel binders such as HTPB, but efforts to further improve the burning rate and mechanical properties of paraffin are still necessary. One approach that is considered in this study is to use multi-walled carbon nanotubes (MWNT) as an additive to paraffin wax. Carbon nanotubes provide increased electrical and thermal conductivity to the solid-fuel grains to which they are added, which can improve the mass burning rate. Furthermore, the addition of ultra-fine aluminum particles to the paraffin/MWNT fuel grains can enhance regression rate of the solid fuel and the density impulse of the hybrid rocket. The multi-walled carbon nanotubes also present the possibility of greatly improving the mechanical properties (e.g., tensile strength) of the paraffin-based solid-fuel grains. For casting these solid-fuel grains, various percentages of MWNT and aluminum particles will be added to the paraffin wax. Previous work has been published about the dispersion and mixing of carbon nanotubes.1 Another manufacturing method has been used for mixing the MWNT with a phenolic resin for ablative applications, and the manufacturing and mixing processes are well-documented in the literature.2 The cost of MWNT is a small fraction of single-walled nanotubes. This is a scale-up advantage as future applications and projects will require low cost additives to maintain cost effectiveness. Testing of the solid-fuel grains will be conducted in several steps. Dog bone samples will be cast and prepared for tensile testing. The fuel samples will also be analyzed using thermogravimetric analysis and a high-resolution scanning electron microscope (SEM). The SEM will allow for examination of the solid fuel grain for uniformity and consistency. The paraffin-based fuel grains will also be tested using two hybrid rocket test motors located at the Pennsylvania State University s High Pressure

  8. Space Shuttle solid rocket booster

    Science.gov (United States)

    Hardy, G. B.

    1979-01-01

    Details of the design, operation, testing and recovery procedures of the reusable solid rocket boosters (SRB) are given. Using a composite PBAN propellant, they will provide the primary thrust (six million pounds maximum at 20 s after ignition) within a 3 g acceleration constraint, as well as thrust vector control for the Space Shuttle. The drogues were tested to a load of 305,000 pounds, and the main parachutes to 205,000. Insulation in the solid rocket motor (SRM) will be provided by asbestos-silica dioxide filled acrylonitrile butadiene rubber ('asbestos filled NBR') except in high erosion areas (principally in the aft dome), where a carbon-filled ethylene propylene diene monomer-neopreme rubber will be utilized. Furthermore, twenty uses for the SRM nozzle will be allowed by its ablative materials, which are principally carbon cloth and silica cloth phenolics.

  9. Program ELM: A tool for rapid thermal-hydraulic analysis of solid-core nuclear rocket fuel elements

    International Nuclear Information System (INIS)

    Walton, J.T.

    1992-11-01

    This report reviews the state of the art of thermal-hydraulic analysis codes and presents a new code, Program ELM, for analysis of fuel elements. ELM is a concise computational tool for modeling the steady-state thermal-hydraulics of propellant flow through fuel element coolant channels in a nuclear thermal rocket reactor with axial coolant passages. The program was developed as a tool to swiftly evaluate various heat transfer coefficient and friction factor correlations generated for turbulent pipe flow with heat addition which have been used in previous programs. Thus, a consistent comparison of these correlations was performed, as well as a comparison with data from the NRX reactor experiments from the Nuclear Engine for Rocket Vehicle Applications (NERVA) project. This report describes the ELM Program algorithm, input/output, and validation efforts and provides a listing of the code

  10. Formulation, Casting, and Evaluation of Paraffin-Based Solid Fuels Containing Energetic and Novel Additives for Hybrid Rockets

    Science.gov (United States)

    Larson, Daniel B.; Desain, John D.; Boyer, Eric; Wachs, Trevor; Kuo, Kenneth K.; Borduin, Russell; Koo, Joseph H.; Brady, Brian B.; Curtiss, Thomas J.; Story, George

    2012-01-01

    This investigation studied the inclusion of various additives to paraffin wax for use in a hybrid rocket motor. Some of the paraffin-based fuels were doped with various percentages of LiAlH4 (up to 10%). Addition of LiAlH4 at 10% was found to increase regression rates between 7 - 10% over baseline paraffin through tests in a gaseous oxygen hybrid rocket motor. Mass burn rates for paraffin grains with 10% LiAlH4 were also higher than those of the baseline paraffin. RDX was also cast into a paraffin sample via a novel casting process which involved dissolving RDX into dimethylformamide (DMF) solvent and then drawing a vacuum on the mixture of paraffin and RDX/DMF in order to evaporate out the DMF. It was found that although all DMF was removed, the process was not conducive to generating small RDX particles. The slow boiling generated an inhomogeneous mixture of paraffin and RDX. It is likely that superheating the DMF to cause rapid boiling would likely reduce RDX particle sizes. In addition to paraffin/LiAlH4 grains, multi-walled carbon nanotubes (MWNT) were cast in paraffin for testing in a hybrid rocket motor, and assorted samples containing a range of MWNT percentages in paraffin were imaged using SEM. The fuel samples showed good distribution of MWNT in the paraffin matrix, but the MWNT were often agglomerated, indicating that a change to the sonication and mixing processes were required to achieve better uniformity and debundled MWNT. Fuel grains with MWNT fuel grains had slightly lower regression rate, likely due to the increased thermal conductivity to the fuel subsurface, reducing the burning surface temperature.

  11. Experimental investigation of solid rocket motors for small sounding rockets

    Science.gov (United States)

    Suksila, Thada

    2018-01-01

    Experimentation and research of solid rocket motors are important subjects for aerospace engineering students. However, many institutes in Thailand rarely include experiments on solid rocket motors in research projects of aerospace engineering students, mainly because of the complexity of mixing the explosive propellants. This paper focuses on the design and construction of a solid rocket motor for total impulse in the class I-J that can be utilised as a small sounding rocket by researchers in the near future. Initially, the test stands intended for measuring the pressure in the combustion chamber and the thrust of the solid rocket motor were designed and constructed. The basic design of the propellant configuration was evaluated. Several formulas and ratios of solid propellants were compared for achieving the maximum thrust. The convenience of manufacturing and casting of the fabricated solid rocket motors were a critical consideration. The motor structural analysis such as the combustion chamber wall thickness was also discussed. Several types of nozzles were compared and evaluated for ensuring the maximum thrust of the solid rocket motors during the experiments. The theory of heat transfer analysis in the combustion chamber was discussed and compared with the experimental data.

  12. The Advanced Solid Rocket Motor

    Science.gov (United States)

    Mitchell, Royce E.

    1992-01-01

    The Advanced Solid Rocket Motor will utilize improved design features and automated manufacturing methods to produce an inherently safer propulsive system for the Space Shuttle and future launch systems. This second-generation motor will also provide an additional 12,000 pounds of payload to orbit, enhancing the utility and efficiency of the Shuttle system. The new plant will feature strip-wound, asbestos-free insulation; propellant continuous mixing and casting; and extensive robotic systems. Following a series of static tests at the Stennis Space Center, MS flights are targeted to begin in early 1997.

  13. Ignition of Liquid Fuel Spray and Simulated Solid Rocket Fuel by Photoignition of Carbon Nanotube Utilizing a Camera Flash

    Science.gov (United States)

    2011-12-01

    10,11 There has been a recent report on the photoignition of graphene oxide for fuel ignition applications.12 In this report, we will describe the...slide Aluminum foil Glass petri dish Xe flash Camera Sample Black spray paint Figure 2- Schematic and photographs of the experimental setup...Gilje, Sergey Dubin, Alireza Badakhshan, Jabari Farrar, Stephen. A. Danczyk, Richard B. Kaner, “Photothermal Deoxygenation of Graphene Oxide for

  14. Design methods in solid rocket motors

    Energy Technology Data Exchange (ETDEWEB)

    1987-03-01

    A compilation of lectures summarizing the current state-of-the-art in designing solid rocket motors and and their components is presented. The experience of several countries in the use of new technologies and methods is represented. Specific sessions address propellant grains, cases, nozzles, internal thermal insulation, and the general optimization of solid rocket motor designs.

  15. Solid rocket motor cost model

    Science.gov (United States)

    Harney, A. G.; Raphael, L.; Warren, S.; Yakura, J. K.

    1972-01-01

    A systematic and standardized procedure for estimating life cycle costs of solid rocket motor booster configurations. The model consists of clearly defined cost categories and appropriate cost equations in which cost is related to program and hardware parameters. Cost estimating relationships are generally based on analogous experience. In this model the experience drawn on is from estimates prepared by the study contractors. Contractors' estimates are derived by means of engineering estimates for some predetermined level of detail of the SRM hardware and program functions of the system life cycle. This method is frequently referred to as bottom-up. A parametric cost analysis is a useful technique when rapid estimates are required. This is particularly true during the planning stages of a system when hardware designs and program definition are conceptual and constantly changing as the selection process, which includes cost comparisons or trade-offs, is performed. The use of cost estimating relationships also facilitates the performance of cost sensitivity studies in which relative and comparable cost comparisons are significant.

  16. ELM - A SIMPLE TOOL FOR THERMAL-HYDRAULIC ANALYSIS OF SOLID-CORE NUCLEAR ROCKET FUEL ELEMENTS

    Science.gov (United States)

    Walton, J. T.

    1994-01-01

    ELM is a simple computational tool for modeling the steady-state thermal-hydraulics of propellant flow through fuel element coolant channels in nuclear thermal rockets. Written for the nuclear propulsion project of the Space Exploration Initiative, ELM evaluates the various heat transfer coefficient and friction factor correlations available for turbulent pipe flow with heat addition. In the past, these correlations were found in different reactor analysis codes, but now comparisons are possible within one program. The logic of ELM is based on the one-dimensional conservation of energy in combination with Newton's Law of Cooling to determine the bulk flow temperature and the wall temperature across a control volume. Since the control volume is an incremental length of tube, the corresponding pressure drop is determined by application of the Law of Conservation of Momentum. The size, speed, and accuracy of ELM make it a simple tool for use in fuel element parametric studies. ELM is a machine independent program written in FORTRAN 77. It has been successfully compiled on an IBM PC compatible running MS-DOS using Lahey FORTRAN 77, a DEC VAX series computer running VMS, and a Sun4 series computer running SunOS UNIX. ELM requires 565K of RAM under SunOS 4.1, 360K of RAM under VMS 5.4, and 406K of RAM under MS-DOS. Because this program is machine independent, no executable is provided on the distribution media. The standard distribution medium for ELM is one 5.25 inch 360K MS-DOS format diskette. ELM was developed in 1991. DEC, VAX, and VMS are trademarks of Digital Equipment Corporation. Sun4 and SunOS are trademarks of Sun Microsystems, Inc. IBM PC is a registered trademark of International Business Machines. MS-DOS is a registered trademark of Microsoft Corporation.

  17. Infrared Imagery of Solid Rocket Exhaust Plumes

    Science.gov (United States)

    Moran, Robert P.; Houston, Janice D.

    2011-01-01

    The Ares I Scale Model Acoustic Test program consisted of a series of 18 solid rocket motor static firings, simulating the liftoff conditions of the Ares I five-segment Reusable Solid Rocket Motor Vehicle. Primary test objectives included acquiring acoustic and pressure data which will be used to validate analytical models for the prediction of Ares 1 liftoff acoustics and ignition overpressure environments. The test article consisted of a 5% scale Ares I vehicle and launch tower mounted on the Mobile Launch Pad. The testing also incorporated several Water Sound Suppression Systems. Infrared imagery was employed during the solid rocket testing to support the validation or improvement of analytical models, and identify corollaries between rocket plume size or shape and the accompanying measured level of noise suppression obtained by water sound suppression systems.

  18. Development of high performance hybrid rocket fuels

    Science.gov (United States)

    Zaseck, Christopher R.

    In this document I discuss paraffin fuel combustion and investigate the effects of additives on paraffin entrainment and regression. In general, hybrid rockets offer an economical and safe alternative to standard liquid and solid rockets. However, slow polymeric fuel regression and low combustion efficiency have limited the commercial use of hybrid rockets. Paraffin is a fast burning fuel that has received significant attention in the 2000's and 2010's as a replacement for standard fuels. Paraffin regresses three to four times faster than polymeric fuels due to the entrainment of a surface melt layer. However, further regression rate enhancement over the base paraffin fuel is necessary for widespread hybrid rocket adoption. I use a small scale opposed flow burner to investigate the effect of additives on the combustion of paraffin. Standard additives such as aluminum combust above the flame zone where sufficient oxidizer levels are present. As a result no heat is generated below the flame itself. In small scale opposed burner experiments the effect of limited heat feedback is apparent. Aluminum in particular does not improve the regression of paraffin in the opposed burner. The lack of heat feedback from additive combustion limits the applicability of the opposed burner. In turn, the results obtained in the opposed burner with metal additive loaded hybrid fuels do not match results from hybrid rocket experiments. In addition, nano-scale aluminum increases melt layer viscosity and greatly slows the regression of paraffin in the opposed flow burner. However, the reactive additives improve the regression rate of paraffin in the opposed burner where standard metals do not. At 5 wt.% mechanically activated titanium and carbon (Ti-C) improves the regression rate of paraffin by 47% in the opposed burner. The mechanically activated Ti C likely reacts in or near the melt layer and provides heat feedback below the flame region that results in faster opposed burner regression

  19. Combustion of metal agglomerates in a solid rocket core flow

    Science.gov (United States)

    Maggi, Filippo; Dossi, Stefano; DeLuca, Luigi T.

    2013-12-01

    The need for access to space may require the use of solid propellants. High thrust and density are appealing features for different applications, spanning from boosting phase to other service applications (separation, de-orbiting, orbit insertion). Aluminum is widely used as a fuel in composite solid rocket motors because metal oxidation increases enthalpy release in combustion chamber and grants higher specific impulse. Combustion process of metal particles is complex and involves aggregation, agglomeration and evolution of reacting particulate inside the core flow of the rocket. It is always stated that residence time should be enough in order to grant complete metal oxidation but agglomerate initial size, rocket grain geometry, burning rate, and other factors have to be reconsidered. New space missions may not require large rocket systems and metal combustion efficiency becomes potentially a key issue to understand whether solid propulsion embodies a viable solution or liquid/hybrid systems are better. A simple model for metal combustion is set up in this paper. Metal particles are represented as single drops trailed by the core flow and reacted according to Beckstead's model. The fluid dynamics is inviscid, incompressible, 1D. The paper presents parametric computations on ideal single-size particles as well as on experimental agglomerate populations as a function of operating rocket conditions and geometries.

  20. Technology for low cost solid rocket boosters.

    Science.gov (United States)

    Ciepluch, C.

    1971-01-01

    A review of low cost large solid rocket motors developed at the Lewis Research Center is given. An estimate is made of the total cost reduction obtainable by incorporating this new technology package into the rocket motor design. The propellant, case material, insulation, nozzle ablatives, and thrust vector control are discussed. The effect of the new technology on motor cost is calculated for a typical expandable 260-in. booster application. Included in the cost analysis is the influence of motor performance variations due to specific impulse and weight changes. It is found for this application that motor costs may be reduced by up to 30% and that the economic attractiveness of future large solid rocket motors will be improved when the new technology is implemented.

  1. Flow-Structural Interaction in Solid Rocket Motors

    National Research Council Canada - National Science Library

    Murdock, John

    2004-01-01

    .... The static test failure of the Titan solid rocket motor upgrade (SRMU) that occurred on 1 April, 1991, demonstrated the importance of flow-structural modeling in the design of large, solid rocket motors...

  2. Rocket Solid Propellant Alternative Based on Ammonium Dinitramide

    Directory of Open Access Journals (Sweden)

    Grigore CICAN

    2017-03-01

    Full Text Available Due to the continuous run for a green environment the current article proposes a new type of solid propellant based on the fairly new synthesized oxidizer, ammonium dinitramide (ADN. Apart of having a higher specific impulse than the worldwide renowned oxidizer, ammonium perchlorate, ADN has the advantage, of leaving behind only nitrogen, oxygen and water after decomposing at high temperatures and therefore totally avoiding the formation of hydrogen chloride fumes. Based on the oxidizer to fuel ratios of the current formulations of the major rocket solid booster (e.g. Space Shuttle’s SRB, Ariane 5’s SRB which comprises mass variations of ammonium perchlorate oxidizer (70-75%, atomized aluminum powder (10-18% and polybutadiene binder (12-20% a new solid propellant was formulated. As previously stated, the new propellant formula and its variations use ADN as oxidizer and erythritol tetranitrate as fuel, keeping the same polybutadiene as binder.

  3. Solid Rocket Testing at AFRL (Briefing Charts)

    Science.gov (United States)

    2016-10-21

    Distribution Unlimited. PA#16492 2 Agenda • Solid Rocket Motors • History of Sea Level Testing • Small Component Testing • Full-scale Testing • Altitude...Facility • History of Testing • Questions -Distribution A: Approved for Public Release; Distribution Unlimited. PA#16492 3 RQ-West • AFRL/RQ...INTEGRATION FACILITY NATIONAL HOVER TEST FACILITY TITAN SRM TEST FACILITY TS-1C1-125 LARGE ENGINE/COMPONENT TEST FACILITY TS-1A 1-120 1-115 X-33 LAUNCH

  4. A Multiconstrained Ascent Guidance Method for Solid Rocket-Powered Launch Vehicles

    Directory of Open Access Journals (Sweden)

    Si-Yuan Chen

    2016-01-01

    Full Text Available This study proposes a multiconstrained ascent guidance method for a solid rocket-powered launch vehicle, which uses a hypersonic glide vehicle (HGV as payload and shuts off by fuel exhaustion. First, pseudospectral method is used to analyze the two-stage launch vehicle ascent trajectory with different rocket ignition modes. Then, constraints, such as terminal height, velocity, flight path angle, and angle of attack, are converted into the constraints within height-time profile according to the second-stage rocket flight characteristics. The closed-loop guidance method is inferred by different spline curves given the different terminal constraints. Afterwards, a thrust bias energy management strategy is proposed to waste the excess energy of the solid rocket. Finally, the proposed method is verified through nominal and dispersion simulations. The simulation results show excellent applicability and robustness of this method, which can provide a valuable reference for the ascent guidance of solid rocket-powered launch vehicles.

  5. The Chameleon Solid Rocket Propulsion Model

    International Nuclear Information System (INIS)

    Robertson, Glen A.

    2010-01-01

    The Khoury and Weltman (2004a and 2004b) Chameleon Model presents an addition to the gravitation force and was shown by the author (Robertson, 2009a and 2009b) to present a new means by which one can view other forces in the Universe. The Chameleon Model is basically a density-dependent model and while the idea is not new, this model is novel in that densities in the Universe to include the vacuum of space are viewed as scalar fields. Such an analogy gives the Chameleon scalar field, dark energy/dark matter like characteristics; fitting well within cosmological expansion theories. In respect to this forum, in this paper, it is shown how the Chameleon Model can be used to derive the thrust of a solid rocket motor. This presents a first step toward the development of new propulsion models using density variations verse mass ejection as the mechanism for thrust. Further, through the Chameleon Model connection, these new propulsion models can be tied to dark energy/dark matter toward new space propulsion systems utilizing the vacuum scalar field in a way understandable by engineers, the key toward the development of such systems. This paper provides corrections to the Chameleon rocket model in Robertson (2009b).

  6. Unsupervised Anomaly Detection for Liquid-Fueled Rocket Prop...

    Data.gov (United States)

    National Aeronautics and Space Administration — Title: Unsupervised Anomaly Detection for Liquid-Fueled Rocket Propulsion Health Monitoring. Abstract: This article describes the results of applying four...

  7. Solid Rocket Motor Design Using Hybrid Optimization

    Directory of Open Access Journals (Sweden)

    Kevin Albarado

    2012-01-01

    Full Text Available A particle swarm/pattern search hybrid optimizer was used to drive a solid rocket motor modeling code to an optimal solution. The solid motor code models tapered motor geometries using analytical burn back methods by slicing the grain into thin sections along the axial direction. Grains with circular perforated stars, wagon wheels, and dog bones can be considered and multiple tapered sections can be constructed. The hybrid approach to optimization is capable of exploring large areas of the solution space through particle swarming, but is also able to climb “hills” of optimality through gradient based pattern searching. A preliminary method for designing tapered internal geometry as well as tapered outer mold-line geometry is presented. A total of four optimization cases were performed. The first two case studies examines designing motors to match a given regressive-progressive-regressive burn profile. The third case study studies designing a neutrally burning right circular perforated grain (utilizing inner and external geometry tapering. The final case study studies designing a linearly regressive burning profile for right circular perforated (tapered grains.

  8. Metallic hydrogen: The most powerful rocket fuel yet to exist

    Energy Technology Data Exchange (ETDEWEB)

    Silvera, Isaac F [Lyman Laboratory of Physics, Harvard University, Cambridge MA 02138 (United States); Cole, John W, E-mail: silvera@physics.harvard.ed [NASA MSFC, Huntsville, AL 35801 (United States)

    2010-03-01

    Wigner and Huntington first predicted that pressures of order 25 GPa were required for the transition of solid molecular hydrogen to the atomic metallic phase. Later it was predicted that metallic hydrogen might be a metastable material so that it remains metallic when pressure is released. Experimental pressures achieved on hydrogen have been more than an order of magnitude higher than the predicted transition pressure and yet it remains an insulator. We discuss the applications of metastable metallic hydrogen to rocketry. Metastable metallic hydrogen would be a very light-weight, low volume, powerful rocket propellant. One of the characteristics of a propellant is its specific impulse, I{sub sp}. Liquid (molecular) hydrogen-oxygen used in modern rockets has an Isp of {approx}460s; metallic hydrogen has a theoretical I{sub sp} of 1700s. Detailed analysis shows that such a fuel would allow single-stage rockets to enter into orbit or carry economical payloads to the moon. If pure metallic hydrogen is used as a propellant, the reaction chamber temperature is calculated to be greater than 6000 K, too high for currently known rocket engine materials. By diluting metallic hydrogen with liquid hydrogen or water, the reaction temperature can be reduced, yet there is still a significant performance improvement for the diluted mixture.

  9. Space shuttle with common fuel tank for liquid rocket booster and main engines (supertanker space shuttle)

    Science.gov (United States)

    Thorpe, Douglas G.

    1991-01-01

    An operation and schedule enhancement is shown that replaces the four-body cluster (Space Shuttle Orbiter (SSO), external tank, and two solid rocket boosters) with a simpler two-body cluster (SSO and liquid rocket booster/external tank). At staging velocity, the booster unit (liquid-fueled booster engines and vehicle support structure) is jettisoned while the remaining SSO and supertank continues on to orbit. The simpler two-bodied cluster reduces the processing and stack time until SSO mate from 57 days (for the solid rocket booster) to 20 days (for the liquid rocket booster). The areas in which liquid booster systems are superior to solid rocket boosters are discussed. Alternative and future generation vehicles are reviewed to reveal greater performance and operations enhancements with more modifications to the current methods of propulsion design philosophy, e.g., combined cycle engines, and concentric propellant tanks.

  10. Integral performance optimum design for multistage solid propellant rocket motors

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hongtao (Shaanxi Power Machinery Institute (China))

    1989-04-01

    A mathematical model for integral performance optimization of multistage solid propellant rocket motors is presented. A calculation on a three-stage, volume-fixed, solid propellant rocket motor is used as an example. It is shown that the velocity at burnout of intermediate-range or long-range ballistic missile calculated using this model is four percent greater than that using the usual empirical method.

  11. Study of solid rocket motor for space shuttle booster, volume 2, book 1

    Science.gov (United States)

    1972-01-01

    The technical requirements for the solid propellant rocket engine to be used with the space shuttle orbiter are presented. The subjects discussed are: (1) propulsion system definition, (2) solid rocket engine stage design, (3) solid rocket engine stage recovery, (4) environmental effects, (5) manrating of the solid rocket engine stage, (6) system safety analysis, and (7) ground support equipment.

  12. Solid electrolyte fuel cells

    Science.gov (United States)

    Isaacs, H. S.

    Progress in the development of functioning solid electrolyte fuel cells is summarized. The solid electrolyte cells perform at 1000 C, a temperature elevated enough to indicate high efficiencies are available, especially if the cell is combined with a steam generator/turbine system. The system is noted to be sulfur tolerant, so coal containing significant amounts of sulfur is expected to yield satisfactory performances with low parasitic losses for gasification and purification. Solid oxide systems are electrically reversible, and are usable in both fuel cell and electrolysis modes. Employing zirconium and yttrium in the electrolyte provides component stability with time, a feature not present with other fuel cells. The chemical reactions producing the cell current are reviewed, along with materials choices for the cathodes, anodes, and interconnections.

  13. Chemicals - potential substances for WMD creation, explosives and rocket fuel

    International Nuclear Information System (INIS)

    Vorozhtsova, M.D.; Khakimova, N.U.; Barotov, M.A.

    2010-01-01

    fluoropolymer (teflon) production, in metallurgy, during glass reprocessing and others. Chlorine trifluoride - ClF_3 - has wide range. It is applied for nuclear materials conversion, rocket fuel additive as well as for semiconductors production in military field. ClF_3 is colorless gas and has sweetish smell, toxic and strong oxidizer. In this article just some chemicals of CHW production are presented. Chemicals are also potential components of strong explosives. Explosives are known as: cyclonite, octogen, triamino trinitrobenzol, solid oxidant (for example, ammonium perchlorate) and others. Chemicals are widely used in rocket fuel production: combustible chemicals; solid and liquid oxidants; binding polymers; other additives. Solid fuel - admixture of many chemicals and connecting components and usually consist from oxidant and de oxidizer. Liquid fuel - also admixture of different liquid chemicals. Usually for rocket fuel NH_4ClO_4 is widely used, hydrazine, hydrides monomethyl, aluminium powder, AlH_3, nitrogen oxide, nitric acids. Some words about heavy water - D_2O, which is moderator in nuclear reactors, ensures continuous nuclear chain reaction with use of natural uranium. D_2O - colorless liquid, external view doesn't differ from H_2O and not radioactive. Its density is 10% more than H_2O. Thus, in this article the chemical substances are presented which are used for WMD, explosives and rocket fuel production. That's why control and exact identification of these substances is guarantee of weapons of mass destruction (WMD) non-proliferation.

  14. Solid Oxide Fuel Cell

    DEFF Research Database (Denmark)

    2010-01-01

    The solid oxide fuel cell comprising a metallic support material, an active anode layer consisting of a good hydrocarbon cracking catalyst, an electrolyte layer, an active cathode layer, and a transition layer consisting of preferably a mixture of LSM and a ferrite to the cathode current collector...

  15. Grooved Fuel Rings for Nuclear Thermal Rocket Engines

    Science.gov (United States)

    Emrich, William

    2009-01-01

    An alternative design concept for nuclear thermal rocket engines for interplanetary spacecraft calls for the use of grooved-ring fuel elements. Beyond spacecraft rocket engines, this concept also has potential for the design of terrestrial and spacecraft nuclear electric-power plants. The grooved ring fuel design attempts to retain the best features of the particle bed fuel element while eliminating most of its design deficiencies. In the grooved ring design, the hydrogen propellant enters the fuel element in a manner similar to that of the Particle Bed Reactor (PBR) fuel element.

  16. Evaluation of the Effect of Exhausts from Liquid and Solid Rockets on Ozone Layer

    Science.gov (United States)

    Yamagiwa, Yoshiki; Ishimaki, Tetsuya

    This paper reports the analytical results of the influences of solid rocket and liquid rocket exhausts on ozone layer. It is worried about that the exhausts from solid propellant rockets cause the ozone depletion in the ozone layer. Some researchers try to develop the analytical model of ozone depletion by rocket exhausts to understand its physical phenomena and to find the effective design of rocket to minimize its effect. However, these models do not include the exhausts from liquid rocket although there are many cases to use solid rocket boosters with a liquid rocket at the same time in practical situations. We constructed combined analytical model include the solid rocket exhausts and liquid rocket exhausts to analyze their effects. From the analytical results, we find that the exhausts from liquid rocket suppress the ozone depletion by solid rocket exhausts.

  17. Parameters Affecting the Erosive Burning of Solid Rocket Motor

    OpenAIRE

    Abdelaziz Almostafa; Guozhu Liang; Elsayed Anwer

    2018-01-01

    Increasing the velocity of gases inside solid rocket motors with low port-to-throat area ratios, leading to increased occurrence and severity of burning rate augmentation due to flow of propellant products across burning propellant surfaces (erosive burning), erosive burning of high energy composite propellant was investigated to supply rocket motor design criteria and to supplement knowledge of combustion phenomena, pressure, burning rate and high velocity of gases all of these are parameter...

  18. Linear stability analysis in a solid-propellant rocket motor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.M.; Kang, K.T.; Yoon, J.K. [Agency for Defense Development, Taejon (Korea, Republic of)

    1995-10-01

    Combustion instability in solid-propellant rocket motors depends on the balance between acoustic energy gains and losses of the system. The objective of this paper is to demonstrate the capability of the program which predicts the standard longitudinal stability using acoustic modes based on linear stability analysis and T-burner test results of propellants. Commercial ANSYS 5.0A program can be used to calculate the acoustic characteristic of a rocket motor. The linear stability prediction was compared with the static firing test results of rocket motors. (author). 11 refs., 17 figs.

  19. Measuring the Internal Environment of Solid Rocket Motors During Ignition

    Science.gov (United States)

    Weisenberg, Brent; Smith, Doug; Speas, Kyle; Corliss, Adam

    2003-01-01

    A new instrumentation system has been developed to measure the internal environment of solid rocket test motors during motor ignition. The system leverages conventional, analog gages with custom designed, electronics modules to provide safe, accurate, high speed data acquisition capability. To date, the instrumentation system has been demonstrated in a laboratory environment and on subscale static fire test motors ranging in size from 5-inches to 24-inches in diameter. Ultimately, this system is intended to be installed on a full-scale Reusable Solid Rocket Motor. This paper explains the need for the data, the components and capabilities of the system, and the test results.

  20. Solid TRU fuels and fuel cycle technology

    International Nuclear Information System (INIS)

    Ogawa, Toru; Suzuki, Yasufumi

    1997-01-01

    Alloys and nitrides are candidate solid fuels for transmutation. However, the nitride fuels are preferred to the alloys because they have more favorable thermal properties which allows to apply a cold-fuel concept. The nitride fuel cycle technology is briefly presented

  1. Hydrodynamic Stability Analysis of Particle-Laden Solid Rocket Motors

    Science.gov (United States)

    Elliott, T. S.; Majdalani, J.

    2014-11-01

    Fluid-wall interactions within solid rocket motors can result in parietal vortex shedding giving rise to hydrodynamic instabilities, or unsteady waves, that translate into pressure oscillations. The oscillations can result in vibrations observed by the rocket, rocket subsystems, or payload, which can lead to changes in flight characteristics, design failure, or other undesirable effects. For many years particles have been embedded in solid rocket propellants with the understanding that their presence increases specific impulse and suppresses fluctuations in the flowfield. This study utilizes a two dimensional framework to understand and quantify the aforementioned two-phase flowfield inside a motor case with a cylindrical grain perforation. This is accomplished through the use of linearized Navier-Stokes equations with the Stokes drag equation and application of the biglobal ansatz. Obtaining the biglobal equations for analysis requires quantification of the mean flowfield within the solid rocket motor. To that end, the extended Taylor-Culick form will be utilized to represent the gaseous phase of the mean flowfield while the self-similar form will be employed for the particle phase. Advancing the mean flowfield by quantifying the particle mass concentration with a semi-analytical solution the finalized mean flowfield is combined with the biglobal equations resulting in a system of eight partial differential equations. This system is solved using an eigensolver within the framework yielding the entire spectrum of eigenvalues, frequency and growth rate components, at once. This work will detail the parametric analysis performed to demonstrate the stabilizing and destabilizing effects of particles within solid rocket combustion.

  2. Hydrodynamic Stability Analysis of Particle-Laden Solid Rocket Motors

    International Nuclear Information System (INIS)

    Elliott, T S; Majdalani, J

    2014-01-01

    Fluid-wall interactions within solid rocket motors can result in parietal vortex shedding giving rise to hydrodynamic instabilities, or unsteady waves, that translate into pressure oscillations. The oscillations can result in vibrations observed by the rocket, rocket subsystems, or payload, which can lead to changes in flight characteristics, design failure, or other undesirable effects. For many years particles have been embedded in solid rocket propellants with the understanding that their presence increases specific impulse and suppresses fluctuations in the flowfield. This study utilizes a two dimensional framework to understand and quantify the aforementioned two-phase flowfield inside a motor case with a cylindrical grain perforation. This is accomplished through the use of linearized Navier-Stokes equations with the Stokes drag equation and application of the biglobal ansatz. Obtaining the biglobal equations for analysis requires quantification of the mean flowfield within the solid rocket motor. To that end, the extended Taylor-Culick form will be utilized to represent the gaseous phase of the mean flowfield while the self-similar form will be employed for the particle phase. Advancing the mean flowfield by quantifying the particle mass concentration with a semi-analytical solution the finalized mean flowfield is combined with the biglobal equations resulting in a system of eight partial differential equations. This system is solved using an eigensolver within the framework yielding the entire spectrum of eigenvalues, frequency and growth rate components, at once. This work will detail the parametric analysis performed to demonstrate the stabilizing and destabilizing effects of particles within solid rocket combustion

  3. Scale Effects on Solid Rocket Combustion Instability Behaviour

    OpenAIRE

    David R. Greatrix

    2011-01-01

    The ability to understand and predict the expected internal behaviour of a given solid-propellant rocket motor under transient conditions is important. Research towards predicting and quantifying undesirable transient axial combustion instability symptoms necessitates a comprehensive numerical model for internal ballistic simulation under dynamic flow and combustion conditions. A numerical model incorporating pertinent elements, such as a representative transient, frequency-dependent combusti...

  4. Electric Propellant Solid Rocket Motor Thruster Results Enabling Small Satellites

    OpenAIRE

    Koehler, Frederick; Langhenry, Mark; Summers, Matt; Villarreal, James; Villarreal, Thomas

    2017-01-01

    Raytheon Missile Systems has developed and tested true on/off/restart solid propellant thrusters which are controlled only by electrical current. This new patented class of energetic rocket propellant is safe, controllable and simple. The range of applications for this game changing technology includes attitude control systems and a safe alternative to higher impulse space satellite thrusters. Described herein are descriptions and performance data for several small electric propellant solid r...

  5. Development of small solid rocket boosters for the ILR-33 sounding rocket

    Science.gov (United States)

    Nowakowski, Pawel; Okninski, Adam; Pakosz, Michal; Cieslinski, Dawid; Bartkowiak, Bartosz; Wolanski, Piotr

    2017-09-01

    This paper gives an overview of the development of a 6000 Newton-class solid rocket motor for suborbital applications. The design configuration and results of interior ballistics calculations are given. The initial use of the motor as the main propulsion system of the H1 experimental in-flight test platform, within the Polish Small Sounding Rocket Program, is presented. Comparisons of theoretical and experimental performance are shown. Both on-ground and in-flight tests are discussed. A novel composite-case manufacturing technology, which enabled to reach high propellant mass fractions, was validated and significant cost-reductions were achieved. This paper focuses on the process of adapting the design for use as the booster stage of the ILR-33 sounding rocket, under development at the Institute of Aviation in Warsaw, Poland. Parallel use of two of the flight-proven rocket motors along with the main stage is planned. The process of adapting the rocket motor for booster application consists of stage integration, aerothermodynamics and reliability analyses. The separation mechanism and environmental impact are also discussed within this paper. Detailed performance analysis with focus on propellant grain geometry is provided. The evolution of the design since the first flights of the H1 rocket is covered and modifications of the manufacturing process are described. Issues of simultaneous ignition of two motors and their non-identical performance are discussed. Further applications and potential for future development are outlined. The presented results are based on the initial work done by the Rocketry Group of the Warsaw University of Technology Students' Space Association. The continuation of the Polish Small Sounding Rocket Program on a larger scale at the Institute of Aviation proves the value of the outcomes of the initial educational project.

  6. Nutation instability of spinning solid rocket motor spacecraft

    Directory of Open Access Journals (Sweden)

    Dan YANG

    2017-08-01

    Full Text Available The variation of mass, and moment of inertia of a spin-stabilized spacecraft leads to concern about the nutation instability. Here a careful analysis on the nutation instability is performed on a spacecraft propelled by solid rocket booster (SRB. The influences of specific solid propellant designs on transversal angular velocity are discussed. The results show that the typical SRB of End Burn suppresses the non-principal axial angular velocity. On the contrary, the frequently used SRB of Radial Burn could amplify the transversal angular velocity. The nutation instability caused by a design of Radial Burn could be remedied by the addition of End Burn at the same time based on the study of the combination design of both End Burn and Radial Burn. The analysis of the results proposes the design conception of how to control the nutation motion. The method is suitable to resolve the nutation instability of solid rocket motor with complex propellant patterns.

  7. A novel kind of solid rocket propellant

    Energy Technology Data Exchange (ETDEWEB)

    Lo, R.E. [Berlin University of Technology (Germany). Rocket Technology at the Aerospace Institute (ILR)

    1998-09-01

    Cryogenic Solid Propellants (CSPs) combine the simplicity of conventional solid propulsion with the high performance of liquid propulsion. By introducing materials that require cooling for remaining solid, CSPs offer an almost unlimited choice of propellant constituents that mights be selected with respect to specific impulse, density or environmental protection. The prize to be paid for these advantages is the necessity of constant cooling and the requirement of special design features that provide combustion control by moving from deflagration to hybrid like boundary layer combustion. This is achieved by building the solid propellant grains out of macroscopic elements rather than using the quasi homogeneous mixture of conventional composites. The elements may be coated, providing protection and support. Different elements may be designed for individual tasks and serve as modules for ignition, sustained combustion, gas generation, combustion efficiency enhancement, etc. Modular dissected grains offer many new ways of interaction inside the combustion chamber and new degrees of freedom for the designer of such `multiple internal hybrid grains`. At a preliminary level, a study finished in Germany 1997 demonstrated large payload gains when the US space Shuttle and the ARIANE 5 boosters were replaced by CSP-boosters. A very preliminary cost analysis resulted in development costs in the usual magnitude (but not in higher ones). Costs of operation were identified as crucial, but not established. Some experimental work in Germany is scheduled to begin in 1998, almost all details in this article (and many more that were not mentioned - most prominent cost analyses of CSP development and operations) wait for deeper analysis and verification. Actually, a whole new world new of world of chemical propulsion awaits exploration. The topic can be looked up and discussed at the web site of the Advanced Propulsion Workshop of the International Academy of Astronautics. The author

  8. Parameters Affecting the Erosive Burning of Solid Rocket Motor

    Directory of Open Access Journals (Sweden)

    Abdelaziz Almostafa

    2018-01-01

    Full Text Available Increasing the velocity of gases inside solid rocket motors with low port-to-throat area ratios, leading to increased occurrence and severity of burning rate augmentation due to flow of propellant products across burning propellant surfaces (erosive burning, erosive burning of high energy composite propellant was investigated to supply rocket motor design criteria and to supplement knowledge of combustion phenomena, pressure, burning rate and high velocity of gases all of these are parameters affect on erosive burning. Investigate the phenomena of the erosive burning by using the 2’inch rocket motor and modified one. Different tests applied to fulfil all the parameters that calculated out from the experiments and by studying the pressure time curve and erosive burning phenomena.

  9. The use of solid phase microextraction as sample preparation technique for determination of n-nitrosodimethylamine in water polluted by hydrazine-based rocket fuel

    Directory of Open Access Journals (Sweden)

    Bulat Kenessov

    2009-05-01

    Full Text Available A paper describes a method for determination of N-nitrosodimethylamine in water, polluted by spills of 1,1-dimethylhydrazine, based on solid phase microextraction coupled to gas chromatography/mass spectrometry. A method detection limit was determined to be 1 ug/kg, relative error was below 20%. A method is very sensitive and selective as well as quite simple, relatively cheap and fully automated.

  10. Specific Impulses Losses in Solid Propellant Rockets

    Science.gov (United States)

    1974-12-17

    the solid we go back to the wall flux. Platinum film thermometric probes [77, 78], developed for somewhat similar problems, were used without succ...AS: E Paper 63-41A 207, 1964. [83) A.D. KIDEIR .A XU - J.A. CAHILL - The density of liquid aluminium oxide. J. Inovg. luc.. Chem. vol.14, no 3-4, p...IELLOR - I. GLL.ASIJ - Augo.nted ignition effi ciency for aluminium . Combustion Science rand Tcchnology, vol. I, p. 437, 1970. [90s EIJ. IJJ tBAU

  11. Longitudinal acoustic instabilities in slender solid propellant rockets : linear analysis

    OpenAIRE

    García Schafer, Juan Esteban; Liñán Martínez, Amable

    2001-01-01

    To describe the acoustic instabilities in the combustion chambers of laterally burning solid propellant rockets the interaction of the mean flow with the acoustic waves is analysed, using multiple scale techniques, for realistic cases in which the combustion chamber is slender and the nozzle area is small compared with the cross-sectional area of the chamber. Associated with the longitudinal acoustic oscillations we find vorticity and entropy waves, with a wavelength typically small compared ...

  12. MEMS-Based Solid Propellant Rocket Array Thruster

    Science.gov (United States)

    Tanaka, Shuji; Hosokawa, Ryuichiro; Tokudome, Shin-Ichiro; Hori, Keiichi; Saito, Hirobumi; Watanabe, Masashi; Esashi, Masayoshi

    The prototype of a solid propellant rocket array thruster for simple attitude control of a 10 kg class micro-spacecraft was completed and tested. The prototype has 10×10 φ0.8 mm solid propellant micro-rockets arrayed at a pitch of 1.2 mm on a 20×22 mm substrate. To realize such a dense array of micro-rockets, each ignition heater is powered from the backside of the thruster through an electrical feedthrough which passes along a propellant cylinder wall. Boron/potassium nitrate propellant (NAB) is used with/without lead rhodanide/potassium chlorate/nitrocellulose ignition aid (RK). Impulse thrust was measured by a pendulum method in air. Ignition required electric power of at least 3 4 W with RK and 4 6 W without RK. Measured impulse thrusts were from 2×10-5 Ns to 3×10-4 Ns after the calculation of compensation for air dumping.

  13. Improving of Hybrid Rocket Engine on the Basis of Optimizing Design Fuel Grain

    Science.gov (United States)

    Oriekov, K. M.; Ushkin, M. P.

    2015-09-01

    This article examines the processes intrachamber in hybrid rocket engine (HRE) and the comparative assessment of the use of solid rocket motors (SRM) and HRE for meteorological rockets with a mass of payload of the 364 kg. Results of the research showed the possibility of a significant increase in the ballistic effectiveness of meteorological rocket.

  14. An improved heat transfer configuration for a solid-core nuclear thermal rocket engine

    International Nuclear Information System (INIS)

    Clark, J.S.; Walton, J.T.; Mcguire, M.L.

    1992-07-01

    Interrupted flow, impingement cooling, and axial power distribution are employed to enhance the heat-transfer configuration of a solid-core nuclear thermal rocket engine. Impingement cooling is introduced to increase the local heat-transfer coefficients between the reactor material and the coolants. Increased fuel loading is used at the inlet end of the reactor to enhance heat-transfer capability where the temperature differences are the greatest. A thermal-hydraulics computer program for an unfueled NERVA reactor core is employed to analyze the proposed configuration with attention given to uniform fuel loading, number of channels through the impingement wafers, fuel-element length, mass-flow rate, and wafer gap. The impingement wafer concept (IWC) is shown to have heat-transfer characteristics that are better than those of the NERVA-derived reactor at 2500 K. The IWC concept is argued to be an effective heat-transfer configuration for solid-core nuclear thermal rocket engines. 11 refs

  15. The Potential for Ozone Depletion in Solid Rocket Motor Plumes by Heterogeneous Chemistry

    National Research Council Canada - National Science Library

    Hanning-Lee, M

    1996-01-01

    ... (hydroxylated alumina), respectively, over the temperature range -60 to 200 degrees C. This work addresses the potential for stratospheric ozone depletion by launch vehicle solid rocket motor exhaust...

  16. Five-Segment Solid Rocket Motor Development Status

    Science.gov (United States)

    Priskos, Alex S.

    2012-01-01

    In support of the National Aeronautics and Space Administration (NASA), Marshall Space Flight Center (MSFC) is developing a new, more powerful solid rocket motor for space launch applications. To minimize technical risks and development costs, NASA chose to use the Space Shuttle s solid rocket boosters as a starting point in the design and development. The new, five segment motor provides a greater total impulse with improved, more environmentally friendly materials. To meet the mass and trajectory requirements, the motor incorporates substantial design and system upgrades, including new propellant grain geometry with an additional segment, new internal insulation system, and a state-of-the art avionics system. Significant progress has been made in the design, development and testing of the propulsion, and avionics systems. To date, three development motors (one each in 2009, 2010, and 2011) have been successfully static tested by NASA and ATK s Launch Systems Group in Promontory, UT. These development motor tests have validated much of the engineering with substantial data collected, analyzed, and utilized to improve the design. This paper provides an overview of the development progress on the first stage propulsion system.

  17. Low Cost Nuclear Thermal Rocket Cermet Fuel Element Environment Testing

    Science.gov (United States)

    Bradley, David E.; Mireles, Omar R.; Hickman, Robert R.

    2011-01-01

    Deep space missions with large payloads require high specific impulse (Isp) and relatively high thrust in order to achieve mission goals in reasonable time frames. Conventional, storable propellants produce average Isp. Nuclear thermal rockets (NTR) capable of high Isp thrust have been proposed. NTR employs heat produced by fission reaction to heat and therefore accelerate hydrogen which is then forced through a rocket nozzle providing thrust. Fuel element temperatures are very high (up to 3000K) and hydrogen is highly reactive with most materials at high temperatures. Data covering the effects of high temperature hydrogen exposure on fuel elements is limited. The primary concern is the mechanical failure of fuel elements which employ high-melting-point metals, ceramics or a combination (cermet) as a structural matrix into which the nuclear fuel is distributed. It is not necessary to include fissile material in test samples intended to explore high temperature hydrogen exposure of the structural support matrices. A small-scale test bed designed to heat fuel element samples via non-contact RF heating and expose samples to hydrogen is being developed to assist in optimal material and manufacturing process selection without employing fissile material. This paper details the test bed design and results of testing conducted to date.

  18. Innovative nuclear thermal rocket concept utilizing LEU fuel for space application

    International Nuclear Information System (INIS)

    Nam, Seung Hyun; Venneri, Paolo; Choi, Jae Young; Jeong, Yong Hoon; Chang, Soon Heung

    2015-01-01

    Space is one of the best places for humanity to turn to keep learning and exploiting. A Nuclear Thermal Rocket (NTR) is a viable and more efficient option for human space exploration than the existing Chemical Rockets (CRs) which are highly inefficient for long-term manned missions such as to Mars and its satellites. NERVA derived NTR engines have been studied for the human missions as a mainstream in the United States of America (USA). Actually, the NERVA technology has already been developed and successfully tested since 1950s. The state-of-the-art technology is based on a Hydrogen gas (H_2) cooled high temperature reactor with solid core utilizing High-Enriched Uranium (HEU) fuel to reduce heavy metal mass and to use fast or epithermal neutron spectrums enabling simple core designs. However, even though the NTR designs utilizing HEU is the best option in terms of rocket performance, they inevitably provoke nuclear proliferation obstacles on all Research and Development (R and D) activities by civilians and non-nuclear weapon states, and its eventual commercialization. To surmount the security issue to use HEU fuel for a NTR, a concept of the innovative NTR engine, Korea Advanced NUclear Thermal Engine Rocket utilizing Low-Enriched Uranium fuel (KANUTER-LEU) is presented in this paper. The design goal of KANUTER-LEU is to make use of a LEU fuel for its compact reactor, but does not sacrifice the rocket performance relative to the traditional NTRs utilizing HEU. KANUTER-LEU mainly consists of a fission reactor utilizing H_2 propellant, a propulsion system and an optional Electricity Generation System as a bimodal engine. To implement LEU fuel for the reactor, the innovative engine adopts W-UO_2 CERMET fuel to drastically increase uranium density and thermal neutron spectrum to improve neutron economy in the core. The moderator and structural material selections also consider neutronic and thermo-physical characteristics to reduce non-fission neutron loss and

  19. Numerical investigation on the regression rate of hybrid rocket motor with star swirl fuel grain

    Science.gov (United States)

    Zhang, Shuai; Hu, Fan; Zhang, Weihua

    2016-10-01

    Although hybrid rocket motor is prospected to have distinct advantages over liquid and solid rocket motor, low regression rate and insufficient efficiency are two major disadvantages which have prevented it from being commercially viable. In recent years, complex fuel grain configurations are attractive in overcoming the disadvantages with the help of Rapid Prototyping technology. In this work, an attempt has been made to numerically investigate the flow field characteristics and local regression rate distribution inside the hybrid rocket motor with complex star swirl grain. A propellant combination with GOX and HTPB has been chosen. The numerical model is established based on the three dimensional Navier-Stokes equations with turbulence, combustion, and coupled gas/solid phase formulations. The calculated fuel regression rate is compared with the experimental data to validate the accuracy of numerical model. The results indicate that, comparing the star swirl grain with the tube grain under the conditions of the same port area and the same grain length, the burning surface area rises about 200%, the spatially averaged regression rate rises as high as about 60%, and the oxidizer can combust sufficiently due to the big vortex around the axis in the aft-mixing chamber. The combustion efficiency of star swirl grain is better and more stable than that of tube grain.

  20. Feasibility study of palm-based fuels for hybrid rocket motor applications

    Science.gov (United States)

    Tarmizi Ahmad, M.; Abidin, Razali; Taha, A. Latif; Anudip, Amzaryi

    2018-02-01

    This paper describes the combined analysis done in pure palm-based wax that can be used as solid fuel in a hybrid rocket engine. The measurement of pure palm wax calorific value was performed using a bomb calorimeter. An experimental rocket engine and static test stand facility were established. After initial measurement and calibration, repeated procedures were performed. Instrumentation supplies carried out allow fuel regression rate measurements, oxidizer mass flow rates and stearic acid rocket motors measurements. Similar tests are also carried out with stearate acid (from palm oil by-products) dissolved with nitrocellulose and bee solution. Calculated data and experiments show that rates and regression thrust can be achieved even in pure-tested palm-based wax. Additionally, palm-based wax is mixed with beeswax characterized by higher nominal melting temperatures to increase moisturizing points to higher temperatures without affecting regression rate values. Calorie measurements and ballistic experiments were performed on this new fuel formulation. This new formulation promises driving applications in a wide range of temperatures.

  1. Maturation of Structural Health Management Systems for Solid Rocket Motors

    Science.gov (United States)

    Quing, Xinlin; Beard, Shawn; Zhang, Chang

    2011-01-01

    Concepts of an autonomous and automated space-compliant diagnostic system were developed for conditioned-based maintenance (CBM) of rocket motors for space exploration vehicles. The diagnostic system will provide real-time information on the integrity of critical structures on launch vehicles, improve their performance, and greatly increase crew safety while decreasing inspection costs. Using the SMART Layer technology as a basis, detailed procedures and calibration techniques for implementation of the diagnostic system were developed. The diagnostic system is a distributed system, which consists of a sensor network, local data loggers, and a host central processor. The system detects external impact to the structure. The major functions of the system include an estimate of impact location, estimate of impact force at impacted location, and estimate of the structure damage at impacted location. This system consists of a large-area sensor network, dedicated multiple local data loggers with signal processing and data analysis software to allow for real-time, in situ monitoring, and longterm tracking of structural integrity of solid rocket motors. Specifically, the system could provide easy installation of large sensor networks, onboard operation under harsh environments and loading, inspection of inaccessible areas without disassembly, detection of impact events and impact damage in real-time, and monitoring of a large area with local data processing to reduce wiring.

  2. Approaches to Low Fuel Regression Rate in Hybrid Rocket Engines

    Directory of Open Access Journals (Sweden)

    Dario Pastrone

    2012-01-01

    Full Text Available Hybrid rocket engines are promising propulsion systems which present appealing features such as safety, low cost, and environmental friendliness. On the other hand, certain issues hamper the development hoped for. The present paper discusses approaches addressing improvements to one of the most important among these issues: low fuel regression rate. To highlight the consequence of such an issue and to better understand the concepts proposed, fundamentals are summarized. Two approaches are presented (multiport grain and high mixture ratio which aim at reducing negative effects without enhancing regression rate. Furthermore, fuel material changes and nonconventional geometries of grain and/or injector are presented as methods to increase fuel regression rate. Although most of these approaches are still at the laboratory or concept scale, many of them are promising.

  3. Power generation from solid fuels

    CERN Document Server

    Spliethoff, Hartmut

    2010-01-01

    Power Generation from Solid Fuels introduces the different technologies to produce heat and power from solid fossil (hard coal, brown coal) and renewable (biomass, waste) fuels, such as combustion and gasification, steam power plants and combined cycles etc. The book discusses technologies with regard to their efficiency, emissions, operational behavior, residues and costs. Besides proven state of the art processes, the focus is on the potential of new technologies currently under development or demonstration. The main motivation of the book is to explain the technical possibilities for reduci

  4. Space shuttle solid rocket booster water entry cavity collapse loads

    Science.gov (United States)

    Keefe, R. T.; Rawls, E. A.; Kross, D. A.

    1982-01-01

    Solid rocket booster cavity collapse flight measurements included external pressures on the motor case and aft skirt, internal motor case pressures, accelerometers located in the forward skirt, mid-body area, and aft skirt, as well as strain gages located on the skin of the motor case. This flight data yielded applied pressure longitudinal and circumferential distributions which compare well with model test predictions. The internal motor case ullage pressure, which is below atmospheric due to the rapid cooling of the hot internal gas, was more severe (lower) than anticipated due to the ullage gas being hotter than predicted. The structural dynamic response characteristics were as expected. Structural ring and wall damage are detailed and are considered to be attributable to the direct application of cavity collapse pressure combined with the structurally destabilizing, low internal motor case pressure.

  5. Scale effects on solid rocket combustion instability behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Greatrix, D. R. [Ryerson University, Department of Aerospace Engineering, Toronto, Ontario (Canada)

    2011-07-01

    The ability to understand and predict the expected internal behaviour of a given solid-propellant rocket motor under transient conditions is important. Research towards predicting and quantifying undesirable transient axial combustion instability symptoms necessitates a comprehensive numerical model for internal ballistic simulation under dynamic flow and combustion conditions. A numerical model incorporating pertinent elements, such as a representative transient, frequency-dependent combustion response to pressure wave activity above the burning propellant surface, is applied to the investigation of scale effects (motor size, i.e., grain length and internal port diameter) on influencing instability-related behaviour in a cylindrical-grain motor. The results of this investigation reveal that the motor's size has a significant influence on transient pressure wave magnitude and structure, and on the appearance and magnitude of an associated base pressure rise. (author)

  6. Scale Effects on Solid Rocket Combustion Instability Behaviour

    Directory of Open Access Journals (Sweden)

    David R. Greatrix

    2011-01-01

    Full Text Available The ability to understand and predict the expected internal behaviour of a given solid-propellant rocket motor under transient conditions is important. Research towards predicting and quantifying undesirable transient axial combustion instability symptoms necessitates a comprehensive numerical model for internal ballistic simulation under dynamic flow and combustion conditions. A numerical model incorporating pertinent elements, such as a representative transient, frequency-dependent combustion response to pressure wave activity above the burning propellant surface, is applied to the investigation of scale effects (motor size, i.e., grain length and internal port diameter on influencing instability-related behaviour in a cylindrical-grain motor. The results of this investigation reveal that the motor’s size has a significant influence on transient pressure wave magnitude and structure, and on the appearance and magnitude of an associated base pressure rise.

  7. Design and Experimental Study on Spinning Solid Rocket Motor

    Science.gov (United States)

    Xue, Heng; Jiang, Chunlan; Wang, Zaicheng

    The study on spinning solid rocket motor (SRM) which used as power plant of twice throwing structure of aerial submunition was introduced. This kind of SRM which with the structure of tangential multi-nozzle consists of a combustion chamber, propellant charge, 4 tangential nozzles, ignition device, etc. Grain design, structure design and prediction of interior ballistic performance were described, and problem which need mainly considered in design were analyzed comprehensively. Finally, in order to research working performance of the SRM, measure pressure-time curve and its speed, static test and dynamic test were conducted respectively. And then calculated values and experimental data were compared and analyzed. The results indicate that the designed motor operates normally, and the stable performance of interior ballistic meet demands. And experimental results have the guidance meaning for the pre-research design of SRM.

  8. Efficient solid rocket propulsion for access to space

    Science.gov (United States)

    Maggi, Filippo; Bandera, Alessio; Galfetti, Luciano; De Luca, Luigi T.; Jackson, Thomas L.

    2010-06-01

    Space launch activity is expected to grow in the next few years in order to follow the current trend of space exploitation for business purpose. Granting high specific thrust and volumetric specific impulse, and counting on decades of intense development, solid rocket propulsion is a good candidate for commercial access to space, even with common propellant formulations. Yet, some drawbacks such as low theoretical specific impulse, losses as well as safety issues, suggest more efficient propulsion systems, digging into the enhancement of consolidated techniques. Focusing the attention on delivered specific impulse, a consistent fraction of losses can be ascribed to the multiphase medium inside the nozzle which, in turn, is related to agglomeration; a reduction of agglomerate size is likely. The present paper proposes a model based on heterogeneity characterization capable of describing the agglomeration trend for a standard aluminized solid propellant formulation. Material microstructure is characterized through the use of two statistical descriptors (pair correlation function and near-contact particles) looking at the mean metal pocket size inside the bulk. Given the real formulation and density of a propellant, a packing code generates the material representative which is then statistically analyzed. Agglomerate predictions are successfully contrasted to experimental data at 5 bar for four different formulations.

  9. Integration of Flex Nozzle System and Electro Hydraulic Actuators to Solid Rocket Motors

    Science.gov (United States)

    Nayani, Kishore Nath; Bajaj, Dinesh Kumar

    2017-10-01

    A rocket motor assembly comprised of solid rocket motor and flex nozzle system. Integration of flex nozzle system and hydraulic actuators to the solid rocket motors are done after transportation to the required place where integration occurred. The flex nozzle system is integrated to the rocket motor in horizontal condition and the electro hydraulic actuators are assembled to the flex nozzle systems. The electro hydraulic actuators are connected to the hydraulic power pack to operate the actuators. The nozzle-motor critical interface are insulation diametrical compression, inhibition resin-28, insulation facial compression, shaft seal `O' ring compression and face seal `O' ring compression.

  10. Solid Oxide Fuel Cell Experimental Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — NETL’s Solid Oxide Fuel Cell Experimental Laboratory in Morgantown, WV, gives researchers access to models and simulations that predict how solid oxide fuel cells...

  11. Experimental validation of solid rocket motor damping models

    Science.gov (United States)

    Riso, Cristina; Fransen, Sebastiaan; Mastroddi, Franco; Coppotelli, Giuliano; Trequattrini, Francesco; De Vivo, Alessio

    2017-12-01

    In design and certification of spacecraft, payload/launcher coupled load analyses are performed to simulate the satellite dynamic environment. To obtain accurate predictions, the system damping properties must be properly taken into account in the finite element model used for coupled load analysis. This is typically done using a structural damping characterization in the frequency domain, which is not applicable in the time domain. Therefore, the structural damping matrix of the system must be converted into an equivalent viscous damping matrix when a transient coupled load analysis is performed. This paper focuses on the validation of equivalent viscous damping methods for dynamically condensed finite element models via correlation with experimental data for a realistic structure representative of a slender launch vehicle with solid rocket motors. A second scope of the paper is to investigate how to conveniently choose a single combination of Young's modulus and structural damping coefficient—complex Young's modulus—to approximate the viscoelastic behavior of a solid propellant material in the frequency band of interest for coupled load analysis. A scaled-down test article inspired to the Z9-ignition Vega launcher configuration is designed, manufactured, and experimentally tested to obtain data for validation of the equivalent viscous damping methods. The Z9-like component of the test article is filled with a viscoelastic material representative of the Z9 solid propellant that is also preliminarily tested to investigate the dependency of the complex Young's modulus on the excitation frequency and provide data for the test article finite element model. Experimental results from seismic and shock tests performed on the test configuration are correlated with numerical results from frequency and time domain analyses carried out on its dynamically condensed finite element model to assess the applicability of different equivalent viscous damping methods to describe

  12. Experimental validation of solid rocket motor damping models

    Science.gov (United States)

    Riso, Cristina; Fransen, Sebastiaan; Mastroddi, Franco; Coppotelli, Giuliano; Trequattrini, Francesco; De Vivo, Alessio

    2018-06-01

    In design and certification of spacecraft, payload/launcher coupled load analyses are performed to simulate the satellite dynamic environment. To obtain accurate predictions, the system damping properties must be properly taken into account in the finite element model used for coupled load analysis. This is typically done using a structural damping characterization in the frequency domain, which is not applicable in the time domain. Therefore, the structural damping matrix of the system must be converted into an equivalent viscous damping matrix when a transient coupled load analysis is performed. This paper focuses on the validation of equivalent viscous damping methods for dynamically condensed finite element models via correlation with experimental data for a realistic structure representative of a slender launch vehicle with solid rocket motors. A second scope of the paper is to investigate how to conveniently choose a single combination of Young's modulus and structural damping coefficient—complex Young's modulus—to approximate the viscoelastic behavior of a solid propellant material in the frequency band of interest for coupled load analysis. A scaled-down test article inspired to the Z9-ignition Vega launcher configuration is designed, manufactured, and experimentally tested to obtain data for validation of the equivalent viscous damping methods. The Z9-like component of the test article is filled with a viscoelastic material representative of the Z9 solid propellant that is also preliminarily tested to investigate the dependency of the complex Young's modulus on the excitation frequency and provide data for the test article finite element model. Experimental results from seismic and shock tests performed on the test configuration are correlated with numerical results from frequency and time domain analyses carried out on its dynamically condensed finite element model to assess the applicability of different equivalent viscous damping methods to describe

  13. Numerical and experimental study of liquid breakup process in solid rocket motor nozzle

    Science.gov (United States)

    Yen, Yi-Hsin

    Rocket propulsion is an important travel method for space exploration and national defense, rockets needs to be able to withstand wide range of operation environment and also stable and precise enough to carry sophisticated payload into orbit, those engineering requirement makes rocket becomes one of the state of the art industry. The rocket family have been classified into two major group of liquid and solid rocket based on the fuel phase of liquid or solid state. The solid rocket has the advantages of simple working mechanism, less maintenance and preparing procedure and higher storage safety, those characters of solid rocket make it becomes popular in aerospace industry. Aluminum based propellant is widely used in solid rocket motor (SRM) industry due to its avalibility, combusion performance and economical fuel option, however after aluminum react with oxidant of amonimum perchrate (AP), it will generate liquid phase alumina (Al2O3) as product in high temperature (2,700˜3,000 K) combustion chamber enviornment. The liquid phase alumina particles aggromorate inside combustion chamber into larger particle which becomes major erosion calprit on inner nozzle wall while alumina aggromorates impinge on the nozzle wall surface. The erosion mechanism result nozzle throat material removal, increase the performance optimized throat diameter and reduce nozzle exit to throat area ratio which leads to the reduction of exhaust gas velocity, Mach number and lower the propulsion thrust force. The approach to avoid particle erosion phenomenon taking place in SRM's nozzle is to reduce the alumina particle size inside combustion chamber which could be done by further breakup of the alumina droplet size in SRM's combustion chamber. The study of liquid breakup mechanism is an important means to smaller combustion chamber alumina droplet size and mitigate the erosion tack place on rocket nozzle region. In this study, a straight two phase air-water flow channel experiment is set up

  14. Development of a new generation solid rocket motor ignition computer code

    Science.gov (United States)

    Foster, Winfred A., Jr.; Jenkins, Rhonald M.; Ciucci, Alessandro; Johnson, Shelby D.

    1994-01-01

    This report presents the results of experimental and numerical investigations of the flow field in the head-end star grain slots of the Space Shuttle Solid Rocket Motor. This work provided the basis for the development of an improved solid rocket motor ignition transient code which is also described in this report. The correlation between the experimental and numerical results is excellent and provides a firm basis for the development of a fully three-dimensional solid rocket motor ignition transient computer code.

  15. Applied algorithm in the liner inspection of solid rocket motors

    Science.gov (United States)

    Hoffmann, Luiz Felipe Simões; Bizarria, Francisco Carlos Parquet; Bizarria, José Walter Parquet

    2018-03-01

    In rocket motors, the bonding between the solid propellant and thermal insulation is accomplished by a thin adhesive layer, known as liner. The liner application method involves a complex sequence of tasks, which includes in its final stage, the surface integrity inspection. Nowadays in Brazil, an expert carries out a thorough visual inspection to detect defects on the liner surface that may compromise the propellant interface bonding. Therefore, this paper proposes an algorithm that uses the photometric stereo technique and the K-nearest neighbor (KNN) classifier to assist the expert in the surface inspection. Photometric stereo allows the surface information recovery of the test images, while the KNN method enables image pixels classification into two classes: non-defect and defect. Tests performed on a computer vision based prototype validate the algorithm. The positive results suggest that the algorithm is feasible and when implemented in a real scenario, will be able to help the expert in detecting defective areas on the liner surface.

  16. Working-cycle processes in solid-propellant rocket engines (Handbook). Rabochie protsessy v raketnykh dvigateliakh tverdogo topliva /Spravochnik/

    Energy Technology Data Exchange (ETDEWEB)

    Shishkov, A.A.; Panin, S.D.; Rumiantsev, B.V.

    1989-01-01

    Physical and mathematical models of processes taking place in solid-propellant rocket engines and gas generators are presented in a systematic manner. The discussion covers the main types of solid propellants, the general design and principal components of solid-propellant rocket engines, the combustion of a solid-propellant charge, thermodynamic calculation of combustion and outflow processes, and analysis of gasdynamic processes in solid-propellant rocket engines. 40 refs.

  17. Composite Solid Fuel: Research of Formation Parameters

    Directory of Open Access Journals (Sweden)

    Tabakaev Roman

    2016-01-01

    Full Text Available Involving of local low-grade fuels resources in fuel and energy balance is actual question of research in the present. In this paper the possibility of processing low-grade fuel in the solid fuel composite was considered. The aim of the work is to define the optimal parameters for formation of the solid composite fuel. A result of researches determined that dextrin content in the binder allows to obtain solid composite fuel having the highest strength. The drying temperature for the various fuels was determined: for pellets production was 20-80 °C, for briquettes – 20-40 °C.

  18. Cooperative Threat Reduction: Solid Rocket Motor Disposition Facility Project (D-2003-131)

    National Research Council Canada - National Science Library

    2003-01-01

    .... DoD contracted with Lockheed Martin Advanced Environmental Systems for $52.4 million to design, develop, fabricate, and test a closed burn, solid rocket motor disposition facility for the Russian Federation in April 1997...

  19. Construction and design of solid-propellant rocket engines. Konstruktsiia i proektirovanie raketnykh dvigatelei tverdogo topliva

    Energy Technology Data Exchange (ETDEWEB)

    Fakhrutdinov, I.K.; Kotel' nikov, A.V.

    1987-01-01

    Methods for assessing the durability of different components of solid-propellant rocket engines are presented. The following aspects of engine development are discussed: task formulation, parameter calculation, construction scheme selection, materials, and durability assessment. 45 references.

  20. Aluminum Agglomeration and Trajectory in Solid Rocket Motors

    National Research Council Canada - National Science Library

    Coats, Douglas; Hylin, E. C; Babbitt, Deborah; Tullos, James A; Beckstead, Merrill; Webb, Michael; Davis, I. L; Dang, Anthony

    2007-01-01

    Report developed under STTR contract for Topic AF06-T012. The demand for higher performance rocket motors at a reduced cost requires continuous improvements in understanding and controlling propellant combustion...

  1. Electrolytes for solid oxide fuel cells

    Science.gov (United States)

    Fergus, Jeffrey W.

    The high operating temperature of solid oxide fuel cells (SOFCs), as compared to polymer electrolyte membrane fuel cells (PEMFCs), improves tolerance to impurities in the fuel, but also creates challenges in the development of suitable materials for the various fuel cell components. In response to these challenges, intermediate temperature solid oxide fuel cells (IT-SOFCs) are being developed to reduce high-temperature material requirements, which will extend useful lifetime, improve durability and reduce cost, while maintaining good fuel flexibility. A major challenge in reducing the operating temperature of SOFCs is the development of solid electrolyte materials with sufficient conductivity to maintain acceptably low ohmic losses during operation. In this paper, solid electrolytes being developed for solid oxide fuel cells, including zirconia-, ceria- and lanthanum gallate-based materials, are reviewed and compared. The focus is on the conductivity, but other issues, such as compatibility with electrode materials, are also discussed.

  2. Electrolytes for solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Fergus, Jeffrey W. [Auburn University, Materials Research and Education Center, 275 Wilmore Laboratories, Auburn, AL 36849 (United States)

    2006-11-08

    The high operating temperature of solid oxide fuel cells (SOFCs), as compared to polymer electrolyte membrane fuel cells (PEMFCs), improves tolerance to impurities in the fuel, but also creates challenges in the development of suitable materials for the various fuel cell components. In response to these challenges, intermediate temperature solid oxide fuel cells (IT-SOFCs) are being developed to reduce high-temperature material requirements, which will extend useful lifetime, improve durability and reduce cost, while maintaining good fuel flexibility. A major challenge in reducing the operating temperature of SOFCs is the development of solid electrolyte materials with sufficient conductivity to maintain acceptably low ohmic losses during operation. In this paper, solid electrolytes being developed for solid oxide fuel cells, including zirconia-, ceria- and lanthanum gallate-based materials, are reviewed and compared. The focus is on the conductivity, but other issues, such as compatibility with electrode materials, are also discussed. (author)

  3. Gas transport in solid oxide fuel cells

    CERN Document Server

    He, Weidong; Dickerson, James

    2014-01-01

    This book provides a comprehensive overview of contemporary research and emerging measurement technologies associated with gas transport in solid oxide fuel cells. Within these pages, an introduction to the concept of gas diffusion in solid oxide fuel cells is presented. This book also discusses the history and underlying fundamental mechanisms of gas diffusion in solid oxide fuel cells, general theoretical mathematical models for gas diffusion, and traditional and advanced techniques for gas diffusivity measurement.

  4. Solid Rocket Booster Large Main and Drogue Parachute Reliability Analysis

    Science.gov (United States)

    Clifford, Courtenay B.; Hengel, John E.

    2009-01-01

    The parachutes on the Space Transportation System (STS) Solid Rocket Booster (SRB) are the means for decelerating the SRB and allowing it to impact the water at a nominal vertical velocity of 75 feet per second. Each SRB has one pilot, one drogue, and three main parachutes. About four minutes after SRB separation, the SRB nose cap is jettisoned, deploying the pilot parachute. The pilot chute then deploys the drogue parachute. The drogue chute provides initial deceleration and proper SRB orientation prior to frustum separation. At frustum separation, the drogue pulls the frustum from the SRB and allows the main parachutes that are mounted in the frustum to unpack and inflate. These chutes are retrieved, inspected, cleaned, repaired as needed, and returned to the flight inventory and reused. Over the course of the Shuttle Program, several improvements have been introduced to the SRB main parachutes. A major change was the replacement of the small (115 ft. diameter) main parachutes with the larger (136 ft. diameter) main parachutes. Other modifications were made to the main parachutes, main parachute support structure, and SRB frustum to eliminate failure mechanisms, improve damage tolerance, and improve deployment and inflation characteristics. This reliability analysis is limited to the examination of the SRB Large Main Parachute (LMP) and drogue parachute failure history to assess the reliability of these chutes. From the inventory analysis, 68 Large Main Parachutes were used in 651 deployments, and 7 chute failures occurred in the 651 deployments. Logistic regression was used to analyze the LMP failure history, and it showed that reliability growth has occurred over the period of use resulting in a current chute reliability of R = .9983. This result was then used to determine the reliability of the 3 LMPs on the SRB, when all must function. There are 29 drogue parachutes that were used in 244 deployments, and no in-flight failures have occurred. Since there are no

  5. Solid fuel applications to transportation engines

    Energy Technology Data Exchange (ETDEWEB)

    Rentz, Richard L.; Renner, Roy A.

    1980-06-01

    The utilization of solid fuels as alternatives to liquid fuels for future transportation engines is reviewed. Alternative liquid fuels will not be addressed nor will petroleum/solid fuel blends except for the case of diesel engines. With respect to diesel engines, coal/oil mixtures will be addressed because of the high interest in this specific application as a result of the large number of diesel engines currently in transportation use. Final assessments refer to solid fuels only for diesel engines. The technical assessments of solid fuels utilization for transportation engines is summarized: solid fuel combustion in transportation engines is in a non-developed state; highway transportation is not amenable to solid fuels utilization due to severe environmental, packaging, control, and disposal problems; diesel and open-cycle gas turbines do not appear worthy of further development, although coal/oil mixtures for slow speed diesels may offer some promise as a transition technology; closed-cycle gas turbines show some promise for solid fuels utilization for limited applications as does the Stirling engine for use of cleaner solid fuels; Rankine cycle engines show good potential for limited applications, such as for locomotives and ships; and any development program will require large resources and sophisticated equipment in order to advance the state-of-the-art.

  6. Numerical Study on Similarity of Plume’s Infrared Radiation from Reduced Scaling Solid Rocket

    Directory of Open Access Journals (Sweden)

    Xiaoying Zhang

    2015-01-01

    Full Text Available Similarity of plume radiation between reduced scaling solid rocket models and full scale ones in ground conditions has been taken for investigation. Flow and radiation of plume from solid rockets with scaling ratio from 0.1 to 1 have been computed. The radiative transfer equation (RTE is solved by the finite volume method (FVM in infrared band 2~6 μm. The spectral characteristics of plume gases have been calculated with the weighted-sum-of-gray-gas (WSGG model, and those of the Al2O3 particles have been solved by the Mie scattering model. Our research shows that, with the decreasing scaling ratio of the rocket engine, the radiation intensity of the plume decreases with 1.5~2.5 power of the scaling ratio. The infrared radiation of the plume gases shows a strong spectral dependency, while that of the Al2O3 particles shows grey property. Spectral radiation intensity of the high temperature core of the solid rocket plume increases greatly in the peak absorption spectrum of plume gases. Al2O3 particle is the major radiation composition in the rocket plume, whose scattering coefficient is much larger than its absorption coefficient. There is good similarity between spectral variations of plumes from different scaling solid rockets. The directional plume radiation rises with the increasing azimuth angle.

  7. Energy properties of solid fossil fuels and solid biofuels

    International Nuclear Information System (INIS)

    Holubcik, Michal; Jandacka, Jozef; Kolkova, Zuzana

    2016-01-01

    The paper deals about the problematic of energy properties of solid biofuels in comparison with solid fossil fuels. Biofuels are alternative to fossil fuels and their properties are very similar. During the experiments were done in detail experiments to obtain various properties of spruce wood pellets and wheat straw pellets like biofuels in comparison with brown coal and black coal like fossil fuels. There were tested moisture content, volatile content, fixed carbon content, ash content, elementary analysis (C, H, N, S content) and ash fusion temperatures. The results show that biofuels have some advantages and also disadvantages in comparison with solid fossil fuels.

  8. Energy properties of solid fossil fuels and solid biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Holubcik, Michal, E-mail: michal.holubcik@fstroj.uniza.sk; Jandacka, Jozef, E-mail: jozef.jandacka@fstroj.uniza.sk [University of Žilina, Faculty of Mechanical Engineering, Department of Power Engineering, Univerzitná 8215/1, 010 26 Žilina (Slovakia); Kolkova, Zuzana, E-mail: zuzana.kolkova@rc.uniza.sk [Research centre, University of Žilina, Univerzitna 8215/1, 010 26 Žilina (Slovakia)

    2016-06-30

    The paper deals about the problematic of energy properties of solid biofuels in comparison with solid fossil fuels. Biofuels are alternative to fossil fuels and their properties are very similar. During the experiments were done in detail experiments to obtain various properties of spruce wood pellets and wheat straw pellets like biofuels in comparison with brown coal and black coal like fossil fuels. There were tested moisture content, volatile content, fixed carbon content, ash content, elementary analysis (C, H, N, S content) and ash fusion temperatures. The results show that biofuels have some advantages and also disadvantages in comparison with solid fossil fuels.

  9. High energy density additives for Hybrid Fuel Rockets to Improve Performance and Enhance Safety

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a conceptual study of prototype strained hydrocarbon molecules as high energy density additives for hybrid rocket fuels to boost the performance of these...

  10. Modeling the Thermal Rocket Fuel Preparation Processes in the Launch Complex Fueling System

    Directory of Open Access Journals (Sweden)

    A. V. Zolin

    2015-01-01

    Full Text Available It is necessary to carry out fuel temperature preparation for space launch vehicles using hydrocarbon propellant components. A required temperature is reached with cooling or heating hydrocarbon fuel in ground facilities fuel storages. Fuel temperature preparing processes are among the most energy-intensive and lengthy processes that require the optimal technologies and regimes of cooling (heating fuel, which can be defined using the simulation of heat exchange processes for preparing the rocket fuel.The issues of research of different technologies and simulation of cooling processes of rocket fuel with liquid nitrogen are given in [1-10]. Diagrams of temperature preparation of hydrocarbon fuel, mathematical models and characteristics of cooling fuel with its direct contact with liquid nitrogen dispersed are considered, using the numerical solution of a system of heat transfer equations, in publications [3,9].Analytical models, allowing to determine the necessary flow rate and the mass of liquid nitrogen and the cooling (heating time fuel in specific conditions and requirements, are preferred for determining design and operational characteristics of the hydrocarbon fuel cooling system.A mathematical model of the temperature preparation processes is developed. Considered characteristics of these processes are based on the analytical solutions of the equations of heat transfer and allow to define operating parameters of temperature preparation of hydrocarbon fuel in the design and operation of the filling system of launch vehicles.The paper considers a technological system to fill the launch vehicles providing the temperature preparation of hydrocarbon gases at the launch site. In this system cooling the fuel in the storage tank before filling the launch vehicle is provided by hydrocarbon fuel bubbling with liquid nitrogen. Hydrocarbon fuel is heated with a pumping station, which provides fuel circulation through the heat exchanger-heater, with

  11. Effect of ammonium perchlorate grain sizes on the combustion of solid rocket propellant

    Energy Technology Data Exchange (ETDEWEB)

    Hegab, A.; Balabel, A. [Menoufia Univ., Menoufia (Egypt). Faculty of Engineering

    2007-07-01

    The combustion of heterogeneous solid rocket propellant consisting of ammonium perchlorate (AP) particles was discussed with reference to the chemical and physical complexity of the propellant and the microscopic scale of the combustion zone. This study considered the primary flame between the decomposition products of the binder and the AP oxidizer; the primary diffusion flame from the oxidizer; density and conductivity of the AP and binder; temperature-dependent gas-phase transport properties; and, an unsteady non-planer regression surface. Three different random packing disc models for the AP particles imbedded in a matrix of a hydroxyl terminated polybutadience (HTPB) fuel-binder were used as a base of the combustion code. The models have different AP grain sizes and distribution with the fuel binder. A 2D calculation was developed for the combustion of heterogeneous solid propellant, accounting for the gas phase physics, the solid phase physics and an unsteady non-planar description of the regressing propellant surface. The mathematical model described the unsteady burning of a heterogeneous propellant by simultaneously solving the combustion fields in the gas phase and the thermal field in the solid phase with appropriate jump condition across the gas/solid interface. The gas-phase kinetics was represented by a two-step reaction mechanism for the primary premixed flame and the primary diffusion flame between the decomposition products of the HTPB and the oxidizer. The essentially-non-oscillatory (ENO) scheme was used to describe the propagation of the unsteady non-planer regression surface. The results showed that AP particle size has a significant effect on the combustion surface deformation as well as on the burning rate. This study also determined the effect of various parameters on the surface propagation speed, flame structure, and the burning surface geometry. The speed by which the combustion surface recedes was found to depend on the exposed pressure

  12. Review of fuel element development for nuclear rocket engines

    International Nuclear Information System (INIS)

    Taub, J.M.

    1975-06-01

    The Los Alamos Scientific Laboratory (LASL) entered the nuclear propulsion field in 1955 and began work on all aspects of a nuclear propulsion program involving uranium-loaded graphite fuels, hydrogen propellant, and a target exhaust temperature of approximately 2500 0 C. A very extensive uranium-loaded graphite fuel element technology evolved from the program. Selection and composition of raw materials for the extrusion mix had to be coupled with heat treatment studies to give optimum element properties. The highly enriched uranium in the element was incorporated as UO 2 , pyrocarbon-coated UC 2 , or solid solution UC . ZrC particles. An extensive development program resulted in successful NbC or ZrC coatings on elements to withstand hydrogen corrosion at elevated temperatures. Hot gas, thermal shock, thermal stress, and NDT evaluation procedures were developed to monitor progress in preparation of elements with optimum properties. Final evaluation was made in reactor tests at NRDS. Aerojet-General, Westinghouse Astronuclear Laboratory, and the Oak Ridge Y-12 Plant of Union Carbide Nuclear Company entered the program in the early 1960's, and their activities paralleled those of LASL in fuel element development. (U.S.)

  13. Combustion diagnosis for analysis of solid propellant rocket abort hazards: Role of spectroscopy

    Science.gov (United States)

    Gill, W.; Cruz-Cabrera, A. A.; Donaldson, A. B.; Lim, J.; Sivathanu, Y.; Bystrom, E.; Haug, A.; Sharp, L.; Surmick, D. M.

    2014-11-01

    Solid rocket propellant plume temperatures have been measured using spectroscopic methods as part of an ongoing effort to specify the thermal-chemical-physical environment in and around a burning fragment of an exploded solid rocket at atmospheric pressures. Such specification is needed for launch safety studies where hazardous payloads become involved with large fragments of burning propellant. The propellant burns in an off-design condition producing a hot gas flame loaded with burning metal droplets. Each component of the flame (soot, droplets and gas) has a characteristic temperature, and it is only through the use of spectroscopy that their temperature can be independently identified.

  14. Combustion diagnosis for analysis of solid propellant rocket abort hazards: Role of spectroscopy

    International Nuclear Information System (INIS)

    Gill, W; Cruz-Cabrera, A A; Bystrom, E; Donaldson, A B; Haug, A; Sharp, L; Lim, J; Sivathanu, Y; Surmick, D M

    2014-01-01

    Solid rocket propellant plume temperatures have been measured using spectroscopic methods as part of an ongoing effort to specify the thermal-chemical-physical environment in and around a burning fragment of an exploded solid rocket at atmospheric pressures. Such specification is needed for launch safety studies where hazardous payloads become involved with large fragments of burning propellant. The propellant burns in an off-design condition producing a hot gas flame loaded with burning metal droplets. Each component of the flame (soot, droplets and gas) has a characteristic temperature, and it is only through the use of spectroscopy that their temperature can be independently identified

  15. Combustion means for solid fuels

    Energy Technology Data Exchange (ETDEWEB)

    Murase, D.

    1987-09-23

    A combustion device for solid fuel, suitable for coal, coke, charcoal, coal-dust briquettes etc., comprising:- a base stand with an opening therein, an imperforate heat resistant holding board locatable to close said opening; a combustion chamber standing on the base stand with the holding board forming the base of the combustion chamber; a wiper arm pivoted for horizontal wiping movement over the upper surface of the holding board; an inlet means at a lower edge of said chamber above the base stand, and/or in a surrounding wall of said chamber, whereby combustion air may enter as exhaust gases leave the combustion chamber; an exhaust pipe for the exhaust gases; generally tubular gas-flow heat-exchange ducting putting the combustion chamber and exhaust pipe into communication; and means capable of moving the holding board into and out of the opening for removal of ash or other residue. The invention can be used for a heating system in a house or in a greenhouse or for a boiler.

  16. Solid propellant processing factor in rocket motor design

    Science.gov (United States)

    1971-01-01

    The ways are described by which propellant processing is affected by choices made in designing rocket engines. Tradeoff studies, design proof or scaleup studies, and special design features are presented that are required to obtain high product quality, and optimum processing costs. Processing is considered to include the operational steps involved with the lining and preparation of the motor case for the grain; the procurement of propellant raw materials; and propellant mixing, casting or extrusion, curing, machining, and finishing. The design criteria, recommended practices, and propellant formulations are included.

  17. Oxy-fuel combustion of solid fuels

    DEFF Research Database (Denmark)

    Toftegaard, Maja Bøg; Brix, Jacob; Jensen, Peter Arendt

    2010-01-01

    Oxy-fuel combustion is suggested as one of the possible, promising technologies for capturing CO2 from power plants. The concept of oxy-fuel combustion is removal of nitrogen from the oxidizer to carry out the combustion process in oxygen and, in most concepts, recycled flue gas to lower the flame...... provide additional options for improvement of process economics are however likewise investigated. Of particular interest is the change of the combustion process induced by the exchange of carbon dioxide and water vapor for nitrogen as diluent. This paper reviews the published knowledge on the oxy......-fuel process and focuses particularly on the combustion fundamentals, i.e. flame temperatures and heat transfer, ignition and burnout, emissions, and fly ash characteristics. Knowledge is currently available regarding both an entire oxy-fuel power plant and the combustion fundamentals. However, several...

  18. The TMI regenerable solid oxide fuel cell

    Science.gov (United States)

    Cable, Thomas L.

    1995-04-01

    Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. These systems generally consist of photovoltaic solar arrays which operate during sunlight cycles to provide system power and regenerate fuel (hydrogen) via water electrolysis; during dark cycles, hydrogen is converted by the fuel cell into system. The currently preferred configuration uses two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Fuel cell/electrolyzer system simplicity, reliability, and power-to-weight and power-to-volume ratios could be greatly improved if both power production (fuel cell) and power storage (electrolysis) functions can be integrated into a single unit. The Technology Management, Inc. (TMI), solid oxide fuel cell-based system offers the opportunity to both integrate fuel cell and electrolyzer functions into one unit and potentially simplify system requirements. Based an the TMI solid oxide fuel cell (SOPC) technology, the TMI integrated fuel cell/electrolyzer utilizes innovative gas storage and operational concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H2O electrode (SOFC anode/electrolyzer cathode) materials for solid oxide, regenerative fuel cells. Improved H2/H2O electrode materials showed improved cell performance in both fuel cell and electrolysis modes in reversible cell tests. ln reversible fuel cell/electrolyzer mode, regenerative fuel cell efficiencies (ratio of power out (fuel cell mode) to power in (electrolyzer model)) improved from 50 percent (using conventional electrode materials) to over 80 percent. The new materials will allow the TMI SOFC system to operate as both the electrolyzer and fuel cell in a single unit. Preliminary system designs have also been developed which indicate the technical feasibility of using the TMI SOFC

  19. Interconnection of bundled solid oxide fuel cells

    Science.gov (United States)

    Brown, Michael; Bessette, II, Norman F; Litka, Anthony F; Schmidt, Douglas S

    2014-01-14

    A system and method for electrically interconnecting a plurality of fuel cells to provide dense packing of the fuel cells. Each one of the plurality of fuel cells has a plurality of discrete electrical connection points along an outer surface. Electrical connections are made directly between the discrete electrical connection points of adjacent fuel cells so that the fuel cells can be packed more densely. Fuel cells have at least one outer electrode and at least one discrete interconnection to an inner electrode, wherein the outer electrode is one of a cathode and and anode and wherein the inner electrode is the other of the cathode and the anode. In tubular solid oxide fuel cells the discrete electrical connection points are spaced along the length of the fuel cell.

  20. Solid oxide fuel cells fueled with reducible oxides

    Science.gov (United States)

    Chuang, Steven S.; Fan, Liang Shih

    2018-01-09

    A direct-electrochemical-oxidation fuel cell for generating electrical energy includes a cathode provided with an electrochemical-reduction catalyst that promotes formation of oxygen ions from an oxygen-containing source at the cathode, a solid-state reduced metal, a solid-state anode provided with an electrochemical-oxidation catalyst that promotes direct electrochemical oxidation of the solid-state reduced metal in the presence of the oxygen ions to produce electrical energy, and an electrolyte disposed to transmit the oxygen ions from the cathode to the solid-state anode. A method of operating a solid oxide fuel cell includes providing a direct-electrochemical-oxidation fuel cell comprising a solid-state reduced metal, oxidizing the solid-state reduced metal in the presence of oxygen ions through direct-electrochemical-oxidation to obtain a solid-state reducible metal oxide, and reducing the solid-state reducible metal oxide to obtain the solid-state reduced metal.

  1. Extension of a simplified computer program for analysis of solid-propellant rocket motors

    Science.gov (United States)

    Sforzini, R. H.

    1973-01-01

    A research project to develop a computer program for the preliminary design and performance analysis of solid propellant rocket engines is discussed. The following capabilities are included as computer program options: (1) treatment of wagon wheel cross sectional propellant configurations alone or in combination with circular perforated grains, (2) calculation of ignition transients with the igniter treated as a small rocket engine, (3) representation of spherical circular perforated grain ends as an alternative to the conical end surface approximation used in the original program, and (4) graphical presentation of program results using a digital plotter.

  2. High energy-density liquid rocket fuel performance

    Science.gov (United States)

    Rapp, Douglas C.

    1990-01-01

    A fuel performance database of liquid hydrocarbons and aluminum-hydrocarbon fuels was compiled using engine parametrics from the Space Transportation Engine Program as a baseline. Propellant performance parameters are introduced. General hydrocarbon fuel performance trends are discussed with respect to hydrogen-to-carbon ratio and heat of formation. Aluminum-hydrocarbon fuel performance is discussed with respect to aluminum metal loading. Hydrocarbon and aluminum-hydrocarbon fuel performance is presented with respect to fuel density, specific impulse and propellant density specific impulse.

  3. A Study of Flame Physics and Solid Propellant Rocket Physics

    Science.gov (United States)

    2007-10-01

    and ellipsoids, and the packing of pellets relevant to igniter modeling. Other topics are the instabilities of smolder waves, premixed flame...instabilities in narrow tubes, and flames supported by a spinning porous plug burner . Much of this work has been reported in the high-quality archival...perchlorate in fuel binder, the combustion of model propellant packs of ellipses and ellipsoids, and the packing of pellets relevant to igniter modeling

  4. Combustion Stability Assessments of the Black Brant Solid Rocket Motor

    Science.gov (United States)

    Fischbach, Sean

    2014-01-01

    The Black Brant variation of the Standard Brant developed in the 1960's has been a workhorse motor of the NASA Sounding Rocket Project Office (SRPO) since the 1970's. In March 2012, the Black Brant Mk1 used on mission 36.277 experienced combustion instability during a flight at White Sands Missile Range, the third event in the last four years, the first occurring in November, 2009, the second in April 2010. After the 2010 event the program has been increasing the motor's throat diameter post-delivery with the goal of lowering the chamber pressure and increasing the margin against combustion instability. During the most recent combustion instability event, the vibrations exceeded the qualification levels for the Flight Termination System. The present study utilizes data generated from T-burner testing of multiple Black Brant propellants at the Naval Air Warfare Center at China Lake, to improve the combustion stability predictions for the Black Brant Mk1 and to generate new predictions for the Mk2. Three unique one dimensional (1-D) stability models were generated, representing distinct Black Brant flights, two of which experienced instabilities. The individual models allowed for comparison of stability characteristics between various nozzle configurations. A long standing "rule of thumb" states that increased stability margin is gained by increasing the throat diameter. In contradiction to this experience based rule, the analysis shows that little or no margin is gained from a larger throat diameter. The present analysis demonstrates competing effects resulting from an increased throat diameter accompanying a large response function. As is expected, more acoustic energy was expelled through the nozzle, but conversely more acoustic energy was generated due to larger gas velocities near the propellant surfaces.

  5. Parametric Study of Design Options aecting Solid Rocket Motor Start-up and Onset of Pressure Oscillations

    OpenAIRE

    Di Giacinto, M.; Cavallini, E.; Favini, B.; Steelant, Johan

    2014-01-01

    The start-up represents a very critical phase during the whole operational life of solid rocket motors. This paper provides a detailed study of the eects on the ignition transient of the main design parameters of solid propellant motors. The analysis is made with the use of a Q1D unsteady model of solid rocket ignition transient, extensively validated in the frame of the VEGA program, for ignition transient predictions and reconstructions, during the last ten years. Two baseline soli...

  6. Jet Fuel Based High Pressure Solid Oxide Fuel Cell System

    Science.gov (United States)

    Gummalla, Mallika (Inventor); Yamanis, Jean (Inventor); Olsommer, Benoit (Inventor); Dardas, Zissis (Inventor); Bayt, Robert (Inventor); Srinivasan, Hari (Inventor); Dasgupta, Arindam (Inventor); Hardin, Larry (Inventor)

    2015-01-01

    A power system for an aircraft includes a solid oxide fuel cell system which generates electric power for the aircraft and an exhaust stream; and a heat exchanger for transferring heat from the exhaust stream of the solid oxide fuel cell to a heat requiring system or component of the aircraft. The heat can be transferred to fuel for the primary engine of the aircraft. Further, the same fuel can be used to power both the primary engine and the SOFC. A heat exchanger is positioned to cool reformate before feeding to the fuel cell. SOFC exhaust is treated and used as inerting gas. Finally, oxidant to the SOFC can be obtained from the aircraft cabin, or exterior, or both.

  7. High-Pressure Burning Rate Studies of Solid Rocket Propellants

    Science.gov (United States)

    2013-01-01

    monopropellant burning rate. The self-de§agration rates of neat AP are plotted in Fig. 2 for both pressed pellets and single crystals. There is agreement...rate data from various investigators: 1 ¡ [2]; pressed pellets : 2 ¡ [3], 3 ¡ [4], and 4 ¡ [2]; and single crystals: 5 ¡ [5], and 6 ¡ [6]. Line ¡ AP...7]. Strand or window burners have had more use in the solid propellant community. There are numerous types and styles of combustion vessels, but they

  8. Seismic tests at the HDR facility using explosives and solid propellant rockets

    International Nuclear Information System (INIS)

    Corvin, P.; Steinhilber, H.

    1981-01-01

    In blast tests the HDR reactor building and its mechanical equipment were subjected to earthquake-type excitations through the soil and the foundation. A series of six tests was carried out, two tests being made with HDR facility under operating conditions (BWR conditions, 285 0 C, 70 bar). The charges were placed in boreholes at a depth of 4 to 10 m and a distance of 16 to 25 m from the reactor building. The tests with solid propellant rockets were made in order to try a new excitation technique. The rockets used in these tests were of compact design and had a short combustion period (500 ms) at high constant thrust (100 kN per combustion chamber). These rockets were fixed to the concrete dome of the building in such a way that the thrust generated during the combustion of the propellant resulted in an impulsive load acting on the building. This type of excitation was selected with a view to investigating the global effects of the load case 'aircraft impact' on the building and the mechanical equipment. In the four tests made so far, up to four rockets were ignited simultaneously, so that the maximum impulse was 2 x 10 5 Ns. The excitation level can be markedly increased by adding further rockets. This excitation technique was characterised by excellent reproducibility of the load parameters. (orig./HP)

  9. Durability of solid oxide fuel cells using sulfur containing fuels

    DEFF Research Database (Denmark)

    Hagen, Anke; Rasmussen, Jens Foldager Bregnballe; Thydén, Karl Tor Sune

    2011-01-01

    The usability of hydrogen and also carbon containing fuels is one of the important advantages of solid oxide fuel cells (SOFCs), which opens the possibility to use fuels derived from conventional sources such as natural gas and from renewable sources such as biogas. Impurities like sulfur compounds...... are critical in this respect. State-of-the-art Ni/YSZ SOFC anodes suffer from being rather sensitive towards sulfur impurities. In the current study, anode supported SOFCs with Ni/YSZ or Ni/ScYSZ anodes were exposed to H2S in the ppm range both for short periods of 24h and for a few hundred hours. In a fuel...

  10. Transient simulation of chamber flowfield in a rod-and-tube configuration solid rocket motor

    International Nuclear Information System (INIS)

    Weaver, J.T.; Stowe, R.A.

    2004-01-01

    Currently, DRDC Valcartier of the Canadian Department of National Defence is designing a prototype rod-and-tube configuration solid propellant rocket motor that will propel a hypersonic velocity missile. This configuration will incorporate a very low port-to-throat area ratio, which in turn results in very high velocity propellant gas traveling across burning propellant surfaces, particularly near the nozzle end of the rocket. This causes an augmentation in the propellant burning rate. While numerical and lumped parameter models are available to design and analyze solid propellant rocket motors and nozzles, many of them provide solutions based on the assumption of quasi-steady flow. Due to the high pressure, high velocity and highly transient nature of the flows expected in the motor under design, it is believed that a CFD simulation will better model the time-dependent phenomena that occur during the functioning of a motor of this type. This simulation couples the fluid dynamics and heat transfer of the gas flowfield within the rocket port to the nozzle and the regression rate of the propellant. By incorporating the regression of the propellant surfaces into the model, the information provided by the resulting time-accurate solution will enable a much improved understanding of the flow phenomena within this rod-and-tube grain motor and a better prediction of the internal ballistics of the motor, which in turn will help in the design of both the motor and the nozzle. (author)

  11. Transient simulation of chamber flowfield in a rod-and-tube configuration solid rocket motor

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, J.T. [Carleton Univ., Ottawa, Ontario (Canada)]. E-mail: jrweaver@storm.ca; Stowe, R.A. [Defence R and D Canada - Valcartier, Val-Belair, Quebec (Canada)

    2004-07-01

    Currently, DRDC Valcartier of the Canadian Department of National Defence is designing a prototype rod-and-tube configuration solid propellant rocket motor that will propel a hypersonic velocity missile. This configuration will incorporate a very low port-to-throat area ratio, which in turn results in very high velocity propellant gas traveling across burning propellant surfaces, particularly near the nozzle end of the rocket. This causes an augmentation in the propellant burning rate. While numerical and lumped parameter models are available to design and analyze solid propellant rocket motors and nozzles, many of them provide solutions based on the assumption of quasi-steady flow. Due to the high pressure, high velocity and highly transient nature of the flows expected in the motor under design, it is believed that a CFD simulation will better model the time-dependent phenomena that occur during the functioning of a motor of this type. This simulation couples the fluid dynamics and heat transfer of the gas flowfield within the rocket port to the nozzle and the regression rate of the propellant. By incorporating the regression of the propellant surfaces into the model, the information provided by the resulting time-accurate solution will enable a much improved understanding of the flow phenomena within this rod-and-tube grain motor and a better prediction of the internal ballistics of the motor, which in turn will help in the design of both the motor and the nozzle. (author)

  12. Production of high-energy substances in the process of thorough treatment of hard rocket fuel

    International Nuclear Information System (INIS)

    Shiman, L.N.; Sobolev, V.V.

    2010-01-01

    The high-energy products taken from hard rocket fuel are explored on the sensitivity to a shock, friction, electrostatic discharge, detonation impulse, vibroloads, and capsule-detonator activity. Their chemical stability, thermal stability, and other physicochemical parameters are studied. The field of a recurring effective utilization of gained octogene, ammonium, and potassium perchlorate is shown.

  13. Failure mode and effects analysis (FMEA) for the Space Shuttle solid rocket motor

    Science.gov (United States)

    Russell, D. L.; Blacklock, K.; Langhenry, M. T.

    1988-01-01

    The recertification of the Space Shuttle Solid Rocket Booster (SRB) and Solid Rocket Motor (SRM) has included an extensive rewriting of the Failure Mode and Effects Analysis (FMEA) and Critical Items List (CIL). The evolution of the groundrules and methodology used in the analysis is discussed and compared to standard FMEA techniques. Especially highlighted are aspects of the FMEA/CIL which are unique to the analysis of an SRM. The criticality category definitions are presented and the rationale for assigning criticality is presented. The various data required by the CIL and contribution of this data to the retention rationale is also presented. As an example, the FMEA and CIL for the SRM nozzle assembly is discussed in detail. This highlights some of the difficulties associated with the analysis of a system with the unique mission requirements of the Space Shuttle.

  14. Neutronics Study on LEU Nuclear Thermal Rocket Fuel Options

    Energy Technology Data Exchange (ETDEWEB)

    Venneri, Paolo; Kim, Yong Hee [KAIST, Daejeon (Korea, Republic of); Howe, Steven [CSNR, Idaho (United States)

    2014-10-15

    This has resulted in a non-trivial simplification of the tasks needed to develop such an engine and the quick initial development of the concept. There are, however, a series of key core-design choices that are currently under scrutiny in the field that have to be resolved in order for the LEU-NTR to be fully developed. The most important of these is the choice of fuel: carbide composite or tungsten cermet. This study presents a first comparison of the two fuel types specifically in the neutronic application to the LEU-NTR, keeping in mind the unique neutronic environment and the system requirements of the system. The scope of the study itself is limited to a neutronics study of the two fuels and only a cursory overview of the material properties of the fuels themselves... The results of this study have led to two major conclusions. First of all is that the carbide composite fuel is, from a neutronics standpoint, a much better fuel. It has a low absorption cross-section, is inherently a strong moderator, is able to achieve a higher reactivity using smaller amounts of fissile material, and can potentially enable a smaller reactor. Second is that despite its neutronic difficulties (high absorption, inferior moderating abilities, and lower k-infinity values) the tungsten cermet fuel is still able to perform satisfactorily in an LEU-NTR, largely due to its ability to have an extremely high fuel loading.

  15. Studies on Flame Spread with Sudden Expansions of Ports of Solid Propellant Rockets under Elevated Pressure.

    OpenAIRE

    B.N. Raghunandan; N.S. Madhavan; C. Sanjeev; V.R.S. Kumar

    1996-01-01

    A detailed experimental study on flame spread over non-uniform ports of solid propellant rockets has been carried out. An idealised. 2-dimensional laboratory motor was used for the experimental study with the aid of cinephotography. Freshly prepared rectangular HTPB propellant with backward facing step was used as the specimenfor this study. It has been shown conclusively that under certain conditions of step location. step height and port height which govern the velocity of gases at the step...

  16. Study of organic ablative thermal-protection coating for solid rocket motor

    Science.gov (United States)

    Hua, Zenggong

    1992-06-01

    A study is conducted to find a new interior thermal-protection material that possesses good thermal-protection performance and simple manufacturing possibilities. Quartz powder and Cr2O3 are investigated using epoxy resin as a binder and Al2O3 as the burning inhibitor. Results indicate that the developed thermal-protection coating is suitable as ablative insulation material for solid rocket motors.

  17. Numerical Evaluation of the Use of Aluminum Particles for Enhancing Solid Rocket Motor Combustion Stability

    OpenAIRE

    David Greatrix

    2015-01-01

    The ability to predict the expected internal behaviour of a given solid-propellant rocket motor under transient conditions is important. Research towards predicting and quantifying undesirable transient axial combustion instability symptoms typically necessitates a comprehensive numerical model for internal ballistic simulation under dynamic flow and combustion conditions. On the mitigation side, one in practice sees the use of inert or reactive particles for the suppression of pressure wave ...

  18. Simulation of Axial Combustion Instability Development and Suppression in Solid Rocket Motors

    OpenAIRE

    David R. Greatrix

    2009-01-01

    In the design of solid-propellant rocket motors, the ability to understand and predict the expected behaviour of a given motor under unsteady conditions is important. Research towards predicting, quantifying, and ultimately suppressing undesirable strong transient axial combustion instability symptoms necessitates a comprehensive numerical model for internal ballistic simulation under dynamic flow and combustion conditions. An updated numerical model incorporating recent developments in predi...

  19. Particle size determination in small solid propellant rocket motors using the diffractively scattered light method.

    OpenAIRE

    Cramer, Robert Grewelle.

    1982-01-01

    Approved for public release; distribution unlimited A dual beam apparatus was developed which simultaneously measured particle size (D32) at the entrance and exit of an exhaust nozzle of a small solid propellant rocket motor. The diameters were determined using measurements of dif fractiveiy scattered laser power spectra. The apparatus was calibrated by using spherical glass beads and aluminum oxide powder. Measurements were successfully made at both locations. Because of...

  20. Provisional 2008 assessment of solid mineral fuels

    International Nuclear Information System (INIS)

    2009-03-01

    This article first comments data on solid mineral fuel consumption in France in 2008, i.e., the overall consumption, and the consumption by different sectors (energy production in coal plants, iron and steel industry, other industries, housing and office buildings). Then, it comments solid mineral fuel imports and their origins. It comments and explains the price evolution since 1999 (notably on the Antwerp-Rotterdam-Amsterdam market) in relationship with maritime transport price, availabilities and problems, and with the evolution of coal demand (notably in China) and oil prices. Finally, it briefly comments the French residual production and stocks

  1. Propellant selection for ramjets with solid fuel

    Energy Technology Data Exchange (ETDEWEB)

    Schmucker, R H; Lips, H

    1976-03-11

    Ramjet propulsion using solid propellant for post-boost acceleration of missiles exhibits several favorable properties, brought about by heterogeneous combustion. A simplified theory for calculating the performance of possible propellants is presented, and they are classified with respect to maximum fuel-specific impulse. The optimal choice of fuel, from a system standpoint, must consider volume constraints, and defines the requirements for motor geometry.

  2. Solid Oxide Fuel Cells Operating on Alternative and Renewable Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaoxing; Quan, Wenying; Xiao, Jing; Peduzzi, Emanuela; Fujii, Mamoru; Sun, Funxia; Shalaby, Cigdem; Li, Yan; Xie, Chao; Ma, Xiaoliang; Johnson, David; Lee, Jeong; Fedkin, Mark; LaBarbera, Mark; Das, Debanjan; Thompson, David; Lvov, Serguei; Song, Chunshan

    2014-09-30

    This DOE project at the Pennsylvania State University (Penn State) initially involved Siemens Energy, Inc. to (1) develop new fuel processing approaches for using selected alternative and renewable fuels – anaerobic digester gas (ADG) and commercial diesel fuel (with 15 ppm sulfur) – in solid oxide fuel cell (SOFC) power generation systems; and (2) conduct integrated fuel processor – SOFC system tests to evaluate the performance of the fuel processors and overall systems. Siemens Energy Inc. was to provide SOFC system to Penn State for testing. The Siemens work was carried out at Siemens Energy Inc. in Pittsburgh, PA. The unexpected restructuring in Siemens organization, however, led to the elimination of the Siemens Stationary Fuel Cell Division within the company. Unfortunately, this led to the Siemens subcontract with Penn State ending on September 23rd, 2010. SOFC system was never delivered to Penn State. With the assistance of NETL project manager, the Penn State team has since developed a collaborative research with Delphi as the new subcontractor and this work involved the testing of a stack of planar solid oxide fuel cells from Delphi.

  3. Numerical study on similarity of plume infrared radiation between reduced-scale solid rocket motors

    Directory of Open Access Journals (Sweden)

    Zhang Xiaoying

    2016-08-01

    Full Text Available This study seeks to determine the similarities in plume radiation between reduced and full-scale solid rocket models in ground test conditions through investigation of flow and radiation for a series of scale ratios ranging from 0.1 to 1. The radiative transfer equation (RTE considering gas and particle radiation in a non-uniform plume has been adopted and solved by the finite volume method (FVM to compute the three dimensional, spectral and directional radiation of a plume in the infrared waveband 2–6 μm. Conditions at wavelengths 2.7 μm and 4.3 μm are discussed in detail, and ratios of plume radiation for reduced-scale through full-scale models are examined. This work shows that, with increasing scale ratio of a computed rocket motor, area of the high-temperature core increases as a 2 power function of the scale ratio, and the radiation intensity of the plume increases with 2–2.5 power of the scale ratio. The infrared radiation of plume gases shows a strong spectral dependency, while that of Al2O3 particles shows spectral continuity of gray media. Spectral radiation intensity of a computed solid rocket plume’s high temperature core increases significantly in peak radiation spectra of plume gases CO and CO2. Al2O3 particles are the major radiation component in a rocket plume. There is good similarity between contours of plume spectral radiance from different scale models of computed rockets, and there are two peak spectra of radiation intensity at wavebands 2.7–3.0 μm and 4.2–4.6 μm. Directed radiation intensity of the entire plume volume will rise with increasing elevation angle.

  4. Rocket Fuel Synthesis by Fisher-Tropsch Process

    Data.gov (United States)

    National Aeronautics and Space Administration — This study aims to investigate the feasibility of using Fisher Tropsch (FT), a commercial-scale technology that currently produces liquid fuels from syngas (CO &...

  5. Mathematical modeling of solid oxide fuel cells

    Science.gov (United States)

    Lu, Cheng-Yi; Maloney, Thomas M.

    1988-01-01

    Development of predictive techniques, with regard to cell behavior, under various operating conditions is needed to improve cell performance, increase energy density, reduce manufacturing cost, and to broaden utilization of various fuels. Such technology would be especially beneficial for the solid oxide fuel cells (SOFC) at it early demonstration stage. The development of computer models to calculate the temperature, CD, reactant distributions in the tubular and monolithic SOFCs. Results indicate that problems of nonuniform heat generation and fuel gas depletion in the tubular cell module, and of size limitions in the monolithic (MOD 0) design may be encountered during FC operation.

  6. Solid recovered fuels in the steel industry.

    Science.gov (United States)

    Kepplinger, Werner L; Tappeiner, Tamara

    2012-04-01

    By using waste materials as alternative fuels in metallurgical plants it is possible to minimize the traditionally used reducing agents, such as coke, coal, oil or natural gas. Moreover, by using waste materials in the metallurgical industry it is feasible to recover these materials as far as possible. This also represents another step towards environmental protection because carbon dioxide emissions can be reduced, if the H(2) content of the waste material is greater in comparison with that of the substituted fuel and the effects of global warming can therefore be reduced. In the present article various solid recovered fuels and their applications in the metallurgical industry are detailed.

  7. Reusable Solid Rocket Motor - Accomplishments, Lessons, and a Culture of Success

    Science.gov (United States)

    Moore, Dennis R.; Phelps, Willie J.

    2011-01-01

    The Reusable Solid Rocket Motor represents the largest solid rocket motor ever flown and the only human rated solid motor. Each Reusable Solid Rocket Motor (RSRM) provides approximately 3-million lb of thrust to lift the integrated Space Shuttle vehicle from the launch pad. The motors burn out approximately 2 minutes later, separate from the vehicle and are recovered and refurbished. The size of the motor and the need for high reliability were challenges. Thrust shaping, via shaping of the propellant grain, was needed to limit structural loads during ascent. The motor design evolved through several block upgrades to increase performance and to increase safety and reliability. A major redesign occurred after STS-51L with the Redesigned Solid Rocket Motor. Significant improvements in the joint sealing systems were added. Design improvements continued throughout the Program via block changes with a number of innovations including development of low temperature o-ring materials and incorporation of a unique carbon fiber rope thermal barrier material. Recovery of the motors and post flight inspection improved understanding of hardware performance, and led to key design improvements. Because of the multidecade program duration material obsolescence was addressed, and requalification of materials and vendors was sometimes needed. Thermal protection systems and ablatives were used to protect the motor cases and nozzle structures. Significant understanding of design and manufacturing features of the ablatives was developed during the program resulting in optimization of design features and processing parameters. The project advanced technology in eliminating ozone-depleting materials in manufacturing processes and the development of an asbestos-free case insulation. Manufacturing processes for the large motor components were unique and safety in the manufacturing environment was a special concern. Transportation and handling approaches were also needed for the large

  8. The TMI Regenerative Solid Oxide Fuel Cell

    Science.gov (United States)

    Cable, Thomas L.; Ruhl, Robert C.; Petrik, Michael

    1996-01-01

    Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. Systems generally consist of photovoltaic solar arrays which operate (during sunlight cycles) to provide system power and regenerate fuel (hydrogen) via water electrolysis and (during dark cycles) fuel cells convert hydrogen into electricity. Common configurations use two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Reliability, power to weight and power to volume ratios could be greatly improved if both power production (fuel cells) and power storage (electrolysis) functions can be integrated into a single unit. The solid oxide fuel cell (SOFC) based design integrates fuel cell and electrolyzer functions and potentially simplifies system requirements. The integrated fuel cell/electrolyzer design also utilizes innovative gas storage concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H20 electrode (SOFC anode/electrolyzer cathode) materials for regenerative fuel cells. Tests have shown improved cell performance in both fuel and electrolysis modes in reversible fuel cell tests. Regenerative fuel cell efficiencies, ratio of power out (fuel cell mode) to power in (electrolyzer mode), improved from 50 percent using conventional electrode materials to over 80 percent. The new materials will allow a single SOFC system to operate as both the electolyzer and fuel cell. Preliminary system designs have also been developed to show the technical feasibility of using the design for space applications requiring high energy storage efficiencies and high specific energy. Small space systems also have potential for dual-use, terrestrial applications.

  9. Modal Survey of ETM-3, A 5-Segment Derivative of the Space Shuttle Solid Rocket Booster

    Science.gov (United States)

    Nielsen, D.; Townsend, J.; Kappus, K.; Driskill, T.; Torres, I.; Parks, R.

    2005-01-01

    The complex interactions between internal motor generated pressure oscillations and motor structural vibration modes associated with the static test configuration of a Reusable Solid Rocket Motor have potential to generate significant dynamic thrust loads in the 5-segment configuration (Engineering Test Motor 3). Finite element model load predictions for worst-case conditions were generated based on extrapolation of a previously correlated 4-segment motor model. A modal survey was performed on the largest rocket motor to date, Engineering Test Motor #3 (ETM-3), to provide data for finite element model correlation and validation of model generated design loads. The modal survey preparation included pretest analyses to determine an efficient analysis set selection using the Effective Independence Method and test simulations to assure critical test stand component loads did not exceed design limits. Historical Reusable Solid Rocket Motor modal testing, ETM-3 test analysis model development and pre-test loads analyses, as well as test execution, and a comparison of results to pre-test predictions are discussed.

  10. Thermo-Structural Response Caused by Structure Gap and Gap Design for Solid Rocket Motor Nozzles

    Directory of Open Access Journals (Sweden)

    Lin Sun

    2016-06-01

    Full Text Available The thermo-structural response of solid rocket motor nozzles is widely investigated in the design of modern rockets, and many factors related to the material properties have been considered. However, little work has been done to evaluate the effects of structure gaps on the generation of flame leaks. In this paper, a numerical simulation was performed by the finite element method to study the thermo-structural response of a typical nozzle with consideration of the structure gap. Initial boundary conditions for thermo-structural simulation were defined by a quasi-1D model, and then coupled simulations of different gap size matching modes were conducted. It was found that frictional interface treatment could efficiently reduce the stress level. Based on the defined flame leak criteria, gap size optimization was carried out, and the best gap matching mode was determined for designing the nozzle. Testing experiment indicated that the simulation results from the proposed method agreed well with the experimental results. It is believed that the simulation method is effective for investigating thermo-structural responses, as well as designing proper gaps for solid rocket motor nozzles.

  11. State Machine Modeling of the Space Launch System Solid Rocket Boosters

    Science.gov (United States)

    Harris, Joshua A.; Patterson-Hine, Ann

    2013-01-01

    The Space Launch System is a Shuttle-derived heavy-lift vehicle currently in development to serve as NASA's premiere launch vehicle for space exploration. The Space Launch System is a multistage rocket with two Solid Rocket Boosters and multiple payloads, including the Multi-Purpose Crew Vehicle. Planned Space Launch System destinations include near-Earth asteroids, the Moon, Mars, and Lagrange points. The Space Launch System is a complex system with many subsystems, requiring considerable systems engineering and integration. To this end, state machine analysis offers a method to support engineering and operational e orts, identify and avert undesirable or potentially hazardous system states, and evaluate system requirements. Finite State Machines model a system as a finite number of states, with transitions between states controlled by state-based and event-based logic. State machines are a useful tool for understanding complex system behaviors and evaluating "what-if" scenarios. This work contributes to a state machine model of the Space Launch System developed at NASA Ames Research Center. The Space Launch System Solid Rocket Booster avionics and ignition subsystems are modeled using MATLAB/Stateflow software. This model is integrated into a larger model of Space Launch System avionics used for verification and validation of Space Launch System operating procedures and design requirements. This includes testing both nominal and o -nominal system states and command sequences.

  12. Injection and swirl driven flowfields in solid and liquid rocket motors

    Science.gov (United States)

    Vyas, Anand B.

    In this work, we seek approximate analytical solutions to describe the bulk flow motion in certain types of solid and liquid rocket motors. In the case of an idealized solid rocket motor, a cylindrical double base propellant grain with steady regression rate is considered. The well known inviscid profile determined by Culick is extended here to include the effects of viscosity and steady grain regression. The approximate analytical solution for the cold flow is obtained from similarity principles, perturbation methods and the method of variation of parameters. The velocity, vorticity, pressure gradient and the shear stress distributions are determined and interpreted for different rates of wall regression and injection Reynolds number. The liquid propellant rocket engine considered here is based on a novel design that gives rise to a cyclonic flow. The resulting bidirectional motion is triggered by the tangential injection of an oxidizer just upstream of the chamber nozzle. Velocity, vorticity and pressure gradient distributions are determined for the bulk gas dynamics using a non-reactive inviscid model. Viscous corrections are then incorporated to explain the formation of a forced vortex near the core. Our results compare favorably with numerical simulations and experimental measurements obtained by other researchers. They also indicate that the bidirectional vortex in a cylindrical chamber is a physical solution of the Euler equations. In closing, we investigate the possibility of multi-directional flow behavior as predicted by Euler's equation and as reported recently in laboratory experiments.

  13. Nuclear Thermal Rocket Design Using LEU Tungsten Fuel

    International Nuclear Information System (INIS)

    Venneri, Paolo; Kim, Yonghee; Husemeyer, Peter and others

    2013-01-01

    This would then open the possibility for the commercial development and implementation of an NTR. The result was a design for a 114.66 kN thrust rocket engine, with an optimized specific impulse of 801 second, and a thrust-to-weight ratio 5.08. The development and analysis of the reactor was done using an integrated neutronics and thermal hydraulics code that combines MCNP5 using ENDF-B/VI cross sections with a purpose-built thermal hydraulics code. A proof of concept has been proposed for W LEU-NTR design. The current design is built upon traditional NTR design work and implements many of the proven design characteristics and materials from previous designs. Despite the current reactor design being preliminary, it already shows promise in being able to have similar, if not better performance characteristics than current and previous NTR designs. Future work will involve the flattening of radial power profile, optimization of the axial power profile, researching methods to address the full water immersion accident scenario, and further studies regarding the breeding potential in the reactor

  14. Nuclear Thermal Rocket Design Using LEU Tungsten Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Venneri, Paolo; Kim, Yonghee; Husemeyer, Peter and others

    2013-10-15

    This would then open the possibility for the commercial development and implementation of an NTR. The result was a design for a 114.66 kN thrust rocket engine, with an optimized specific impulse of 801 second, and a thrust-to-weight ratio 5.08. The development and analysis of the reactor was done using an integrated neutronics and thermal hydraulics code that combines MCNP5 using ENDF-B/VI cross sections with a purpose-built thermal hydraulics code. A proof of concept has been proposed for W LEU-NTR design. The current design is built upon traditional NTR design work and implements many of the proven design characteristics and materials from previous designs. Despite the current reactor design being preliminary, it already shows promise in being able to have similar, if not better performance characteristics than current and previous NTR designs. Future work will involve the flattening of radial power profile, optimization of the axial power profile, researching methods to address the full water immersion accident scenario, and further studies regarding the breeding potential in the reactor.

  15. Reusable Solid Rocket Motor - Accomplishment, Lessons, and a Culture of Success

    Science.gov (United States)

    Moore, D. R.; Phelps, W. J.

    2011-01-01

    The Reusable Solid Rocket Motor (RSRM) represents the largest solid rocket motor (SRM) ever flown and the only human-rated solid motor. High reliability of the RSRM has been the result of challenges addressed and lessons learned. Advancements have resulted by applying attention to process control, testing, and postflight through timely and thorough communication in dealing with all issues. A structured and disciplined approach was taken to identify and disposition all concerns. Careful consideration and application of alternate opinions was embraced. Focus was placed on process control, ground test programs, and postflight assessment. Process control is mandatory for an SRM, because an acceptance test of the delivered product is not feasible. The RSRM maintained both full-scale and subscale test articles, which enabled continuous improvement of design and evaluation of process control and material behavior. Additionally RSRM reliability was achieved through attention to detail in post flight assessment to observe any shift in performance. The postflight analysis and inspections provided invaluable reliability data as it enables observation of actual flight performance, most of which would not be available if the motors were not recovered. RSRM reusability offered unique opportunities to learn about the hardware. NASA is moving forward with the Space Launch System that incorporates propulsion systems that takes advantage of the heritage Shuttle and Ares solid motor programs. These unique challenges, features of the RSRM, materials and manufacturing issues, and design improvements will be discussed in the paper.

  16. Thrust Augmented Nozzle for a Hybrid Rocket with a Helical Fuel Port

    Science.gov (United States)

    Marshall, Joel H.

    A thrust augmented nozzle for hybrid rocket systems is investigated. The design lever-ages 3-D additive manufacturing to embed a helical fuel port into the thrust chamber of a hybrid rocket burning gaseous oxygen and ABS plastic as propellants. The helical port significantly increases how quickly the fuel burns, resulting in a fuel-rich exhaust exiting the nozzle. When a secondary gaseous oxygen flow is injected into the nozzle downstream of the throat, all of the remaining unburned fuel in the plume spontaneously ignites. This secondary reaction produces additional high pressure gases that are captured by the nozzle and significantly increases the motor's performance. Secondary injection and combustion allows a high expansion ratio (area of the nozzle exit divided by area of the throat) to be effective at low altitudes where there would normally be significantly flow separation and possibly an embedded shock wave due. The result is a 15 percent increase in produced thrust level with no loss in engine efficiency due to secondary injection. Core flow efficiency was increased significantly. Control tests performed using cylindrical fuel ports with secondary injection, and helical fuel ports without secondary injection did not exhibit this performance increase. Clearly, both the fuel-rich plume and secondary injection are essential features allowing the hybrid thrust augmentation to occur. Techniques for better design optimization are discussed.

  17. Lessons from half a century experience of Japanese solid rocketry since Pencil rocket

    Science.gov (United States)

    Matogawa, Yasunori

    2007-12-01

    50 years have passed since a tiny rocket "Pencil" was launched horizontally at Kokubunji near Tokyo in 1955. Though there existed high level of rocket technology in Japan before the end of the second World War, it was not succeeded by the country after the War. Pencil therefore was the substantial start of Japanese rocketry that opened the way to the present stage. In the meantime, a rocket group of the University of Tokyo contributed to the International Geophysical Year in 1957-1958 by developing bigger rockets, and in 1970, the group succeeded in injecting first Japanese satellite OHSUMI into earth orbit. It was just before the launch of OHSUMI that Japan had built up the double feature system of science and applications in space efforts. The former has been pursued by ISAS (the Institute of Space and Astronautical Science) of the University of Tokyo, and the latter by NASDA (National Space Development Agency). This unique system worked quite efficiently because space activities in scientific and applicational areas could develop rather independently without affecting each other. Thus Japan's space science ran up rapidly to the international stage under the support of solid propellant rocket technology, and, after a 20 year technological introduction period from the US, a big liquid propellant launch vehicle, H-II, at last was developed on the basis of Japan's own technology in the early 1990's. On October 1, 2003, as a part of Governmental Reform, three Japanese space agencies were consolidated into a single agency, JAXA (Japan Aerospace Exploration Agency), and Japan's space efforts began to walk toward the future in a globally coordinated fashion, including aeronautics, astronautics, space science, satellite technology, etc., at the same time. This paper surveys the history of Japanese rocketry briefly, and draws out the lessons from it to make a new history of Japan's space efforts more meaningful.

  18. Structural and mechanical design challenges of space shuttle solid rocket boosters separation and recovery subsystems

    Science.gov (United States)

    Woodis, W. R.; Runkle, R. E.

    1985-01-01

    The design of the space shuttle solid rocket booster (SRB) subsystems for reuse posed some unique and challenging design considerations. The separation of the SRBs from the cluster (orbiter and external tank) at 150,000 ft when the orbiter engines are running at full thrust meant the two SRBs had to have positive separation forces pushing them away. At the same instant, the large attachments that had reacted launch loads of 7.5 million pounds thrust had to be servered. These design considerations dictated the design requirements for the pyrotechnics and separation rocket motors. The recovery and reuse of the two SRBs meant they had to be safely lowered to the ocean, remain afloat, and be owed back to shore. In general, both the pyrotechnic and recovery subsystems have met or exceeded design requirements. In twelve vehicles, there has only been one instance where the pyrotechnic system has failed to function properly.

  19. Flight demonstration of flight termination system and solid rocket motor ignition using semiconductor laser initiated ordnance

    Science.gov (United States)

    Schulze, Norman R.; Maxfield, B.; Boucher, C.

    1995-01-01

    Solid State Laser Initiated Ordnance (LIO) offers new technology having potential for enhanced safety, reduced costs, and improved operational efficiency. Concerns over the absence of programmatic applications of the technology, which has prevented acceptance by flight programs, should be abated since LIO has now been operationally implemented by the Laser Initiated Ordnance Sounding Rocket Demonstration (LOSRD) Program. The first launch of solid state laser diode LIO at the NASA Wallops Flight Facility (WFF) occurred on March 15, 1995 with all mission objectives accomplished. This project, Phase 3 of a series of three NASA Headquarters LIO demonstration initiatives, accomplished its objective by the flight of a dedicated, all-LIO sounding rocket mission using a two-stage Nike-Orion launch vehicle. LIO flight hardware, made by The Ensign-Bickford Company under NASA's first Cooperative Agreement with Profit Making Organizations, safely initiated three demanding pyrotechnic sequence events, namely, solid rocket motor ignition from the ground and in flight, and flight termination, i.e., as a Flight Termination System (FTS). A flight LIO system was designed, built, tested, and flown to support the objectives of quickly and inexpensively putting LIO through ground and flight operational paces. The hardware was fully qualified for this mission, including component testing as well as a full-scale system test. The launch accomplished all mission objectives in less than 11 months from proposal receipt. This paper concentrates on accomplishments of the ordnance aspects of the program and on the program's implementation and results. While this program does not generically qualify LIO for all applications, it demonstrated the safety, technical, and operational feasibility of those two most demanding applications, using an all solid state safe and arm system in critical flight applications.

  20. Near-ambient solid polymer fuel cell

    Science.gov (United States)

    Holleck, G. L.

    1993-01-01

    Fuel cells are extremely attractive for extraterrestrial and terrestrial applications because of their high energy conversion efficiency without noise or environmental pollution. Among the various fuel cell systems the advanced polymer electrolyte membrane fuel cells based on sulfonated fluoropolymers (e.g., Nafion) are particularly attractive because they are fairly rugged, solid state, quite conductive, of good chemical and thermal stability and show good oxygen reduction kinetics due to the low specific adsorption of the electrolyte on the platinum catalyst. The objective of this program is to develop a solid polymer fuel cell which can efficiently operate at near ambient temperatures without ancillary components for humidification and/or pressurization of the fuel or oxidant gases. During the Phase 1 effort we fabricated novel integral electrode-membrane structures where the dispersed platinum catalyst is precipitated within the Nafion ionomer. This resulted in electrode-membrane units without interfacial barriers permitting unhindered water diffusion from cathode to anode. The integral electrode-membrane structures were tested as fuel cells operating on H2 and O2 or air at 1 to 2 atm and 10 to 50 C without gas humidification. We demonstrated that cells with completely dry membranes could be self started at room temperature and subsequently operated on dry gas for extended time. Typical room temperature low pressure operation with unoptimized electrodes yielded 100 mA/cm(exp 2) at 0.5V and maximum currents over 300 mA/cm(exp 2) with low platinum loadings. Our results clearly demonstrate that operation of proton exchange membrane fuel cells at ambient conditions is feasible. Optimization of the electrode-membrane structure is necessary to assess the full performance potential but we expect significant gains in weight and volume power density for the system. The reduced complexity will make fuel cells also attractive for smaller and portable power supplies and as

  1. Health assessment of children and adolescents living in a residential area of production for the disposal of rocket fuel: according to the results of the medical examination

    Directory of Open Access Journals (Sweden)

    Uiba V.V.

    2014-12-01

    Full Text Available Aim: to determine the real prevalence separate nosological forms in the child population living in residential zone installations for the disposal of rocket fuel. Materials and methods. By mobile teams of pediatric physicians there was conducted a comprehensive medical examination of 1621 children in the area of the site location for disposal of rocket engines solid fuel. Results. The surveyed contingent of the most common diseases of the endocrine system, disorders of nutrition and metabolism (21.2% of diagnoses, diseases of the musculoskeletal and connective tissue (19.2 percent, as well as individual symptoms, signs and deviations from the norm by 14.4%. Conclusion. Data indicating the pronounced impact of adverse environmental factors, not identified.

  2. Development of Displacement Gages Exposed to Solid Rocket Motor Internal Environments

    Science.gov (United States)

    Bolton, D. E.; Cook, D. J.

    2003-01-01

    The Space Shuttle Reusable Solid Rocket Motor (RSRM) has three non-vented segment-to-segment case field joints. These joints use an interference fit J-joint that is bonded at assembly with a Pressure Sensitive Adhesive (PSA) inboard of redundant O-ring seals. Full-scale motor and sub-scale test article experience has shown that the ability to preclude gas leakage past the J-joint is a function of PSA type, joint moisture from pre-assembly humidity exposure, and the magnitude of joint displacement during motor operation. To more accurately determine the axial displacements at the J-joints, two thermally durable displacement gages (one mechanical and one electrical) were designed and developed. The mechanical displacement gage concept was generated first as a non-electrical, self-contained gage to capture the maximum magnitude of the J-joint motion. When it became feasible, the electrical displacement gage concept was generated second as a real-time linear displacement gage. Both of these gages were refined in development testing that included hot internal solid rocket motor environments and simulated vibration environments. As a result of this gage development effort, joint motions have been measured in static fired RSRM J-joints where intentional venting was produced (Flight Support Motor #8, FSM-8) and nominal non-vented behavior occurred (FSM-9 and FSM-10). This data gives new insight into the nominal characteristics of the three case J-joint positions (forward, center and aft) and characteristics of some case J-joints that became vented during motor operation. The data supports previous structural model predictions. These gages will also be useful in evaluating J-joint motion differences in a five-segment Space Shuttle solid rocket motor.

  3. Coupled Fluid-Structure Interaction Analysis of Solid Rocket Motor with Flexible Inhibitors

    Science.gov (United States)

    Yang, H. Q.; West, Jeff; Harris, Robert E.

    2014-01-01

    Flexible inhibitors are generally used in solid rocket motors (SRMs) as a means to control the burning of propellant. Vortices generated by the flow of propellant around the flexible inhibitors have been identified as a driving source of instabilities that can lead to thrust oscillations in launch vehicles. Potential coupling between the SRM thrust oscillations and structural vibration modes is an important risk factor in launch vehicle design. As a means to predict and better understand these phenomena, a multidisciplinary simulation capability that couples the NASA production CFD code, Loci/CHEM, with CFDRC's structural finite element code, CoBi, has been developed. This capability is crucial to the development of NASA's new space launch system (SLS). This paper summarizes the efforts in applying the coupled software to demonstrate and investigate fluid-structure interaction (FSI) phenomena between pressure waves and flexible inhibitors inside reusable solid rocket motors (RSRMs). The features of the fluid and structural solvers are described in detail, and the coupling methodology and interfacial continuity requirements are then presented in a general Eulerian-Lagrangian framework. The simulations presented herein utilize production level CFD with hybrid RANS/LES turbulence modeling and grid resolution in excess of 80 million cells. The fluid domain in the SRM is discretized using a general mixed polyhedral unstructured mesh, while full 3D shell elements are utilized in the structural domain for the flexible inhibitors. Verifications against analytical solutions for a structural model under a steady uniform pressure condition and under dynamic modal analysis show excellent agreement in terms of displacement distribution and eigenmode frequencies. The preliminary coupled results indicate that due to acoustic coupling, the dynamics of one of the more flexible inhibitors shift from its first modal frequency to the first acoustic frequency of the solid rocket motor

  4. Internal Flow Analysis of Large L/D Solid Rocket Motors

    Science.gov (United States)

    Laubacher, Brian A.

    2000-01-01

    Traditionally, Solid Rocket Motor (SRM) internal ballistic performance has been analyzed and predicted with either zero-dimensional (volume filling) codes or one-dimensional ballistics codes. One dimensional simulation of SRM performance is only necessary for ignition modeling, or for motors that have large length to port diameter ratios which exhibit an axial "pressure drop" during the early burn times. This type of prediction works quite well for many types of motors, however, when motor aspect ratios get large, and port to throat ratios get closer to one, two dimensional effects can become significant. The initial propellant grain configuration for the Space Shuttle Reusable Solid Rocket Motor (RSRM) was analyzed with 2-D, steady, axi-symmetric computational fluid dynamics (CFD). The results of the CFD analysis show that the steady-state performance prediction at the initial burn geometry, in general, agrees well with 1-D transient prediction results at an early time, however, significant features of the 2-D flow are captured with the CFD results that would otherwise go unnoticed. Capturing these subtle differences gives a greater confidence to modeling accuracy, and additional insight with which to model secondary internal flow effects like erosive burning. Detailed analysis of the 2-D flowfield has led to the discovery of its hidden 1-D isentropic behavior, and provided the means for a thorough and simplified understanding of internal solid rocket motor flow. Performance parameters such as nozzle stagnation pressure, static pressure drop, characteristic velocity, thrust and specific impulse are discussed in detail and compared for different modeling and prediction methods. The predicted performance using both the 1-D codes and the CFD results are compared with measured data obtained from static tests of the RSRM. The differences and limitations of predictions using ID and 2-D flow fields are discussed and some suggestions for the design of large L/D motors and

  5. Finite element analysis of propellant of solid rocket motor during ship motion

    Directory of Open Access Journals (Sweden)

    Kai Qu

    2013-03-01

    Full Text Available In order to simulate the stress and strain of solid rocket motors (SRMs, a finite element analysis model was established. The stress spectra of the SRM elements with respect to time in the case that the vessel cruises under a certain shipping condition were obtained by simulation. According to the analysis of the simulation results, a critical zone was confirmed, and the Mises stress amplitudes of the different critical zones were acquired. The results show that the maximum stress and strain of SRM are less than the maximum tensile strength and elongation, respectively, of the propellant. The cumulative damage of the motor must also be evaluated by random fatigue loading.

  6. Research on combustion instability and application to solid propellant rocket motors. II.

    Science.gov (United States)

    Culick, F. E. C.

    1972-01-01

    Review of the current state of analyses of combustion instability in solid-propellant rocket motors, citing appropriate measurements and observations. The work discussed has become increasingly important, both for the interpretation of laboratory data and for predicting the transient behavior of disturbances in full-scale motors. Two central questions are considered - namely, linear stability and nonlinear behavior. Several classes of problems are discussed as special cases of a general approach to the analysis of combustion instability. Application to motors, and particularly the limitations presently understood, are stressed.

  7. Study of solid rocket motors for a space shuttle booster. Volume 1: Executive summary

    Science.gov (United States)

    1972-01-01

    The design, development, production, and launch support analysis for determining the solid propellant rocket engine to be used with the space shuttle are discussed. Specific program objectives considered were: (1) definition of engine designs to satisfy the performance and configuration requirements of the various vehicle/booster concepts, (2) definition of requirements to produce booster stages at rates of 60, 40, 20, and 10 launches per year in a man-rated system, and (3) estimation of costs for the defined SRM booster stages.

  8. Stability of solid oxide fuel cell materials

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, T.R.; Bates, J.L.; Chick, L.A. [Pacific Northwest Lab., Richland, WA (United States)

    1996-04-01

    Interconnection materials in a solid oxide fuel cell are exposed to both highly oxidizing conditions at the cathode and to highly reducing conditions at the anode. The thermal expansion characteristics of substituted lanthanum and yttrium chromite interconnect materials were evaluated by dilatometry as a function of oxygen partial pressures from 1 atm to 10{sup -18} atm, controlled using a carbon dioxide/hydrogen buffer.

  9. Thermal characterizations of the paraffin wax/low density polyethylene blends as a solid fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soojong; Moon, Heejang; Kim, Jinkon, E-mail: jkkim@kau.ac.kr

    2015-08-10

    Highlights: • Regression rate of blends fuel is higher than polymer fuel. • LDPE is an effective mixing ingredient for the combustion efficiency. • Blends fuel is a uniform mixture with two degradation steps. • LDPE plays a positive role for the low sensitivity to the thermal deformation • Blends with low LDPE content can be an effective fuel for hybrid rocket application. - Abstract: Thermal characterizations of a novel solid fuel for hybrid rocket application, based on the paraffin wax blends with low density polyethylene (LDPE) concentration of 5% (SF-5) and 10% (SF-10) were conducted. Both the increased regression rate in comparison with the polymeric fuel, and the improved combustion efficiency in comparison with the pure paraffin fuel reveal that the blend fuels achieve higher combustion performance. The morphology of the shape stabilized paraffin wax/LDPE blends was characterized by the scanning electron microscopy (SEM). Although the SEM observation indicated the blends have uniform mixtures, they showed two degradation steps confirming the immiscibility of components in the crystalline phase from thermogravimetric analysis (TGA). The differential scanning calorimeter (DSC) results showed that the melting temperature of LDPE in the blends decreased with an increase of paraffin wax content. The decreasing total specific melting enthalpy of blended fuels with decreasing paraffin wax content is in fairly good agreement with the additive rule. In thermomechanical analysis (TMA), the linear coefficient of thermal expansion (LCTE) seems to decrease with an increase of LDPE loading, however, the loaded LDPE do merely affect the LCTE in case of the blends with low LDPE concentration. It was found that a blend of low concentration of LDPE with a relatively high concentration of paraffin wax can lead to a potential novel fuel for rocket application, a contrary case with respect to the field of phase change materials (PCM) where a blend of high concentration

  10. Thermal characterizations of the paraffin wax/low density polyethylene blends as a solid fuel

    International Nuclear Information System (INIS)

    Kim, Soojong; Moon, Heejang; Kim, Jinkon

    2015-01-01

    Highlights: • Regression rate of blends fuel is higher than polymer fuel. • LDPE is an effective mixing ingredient for the combustion efficiency. • Blends fuel is a uniform mixture with two degradation steps. • LDPE plays a positive role for the low sensitivity to the thermal deformation • Blends with low LDPE content can be an effective fuel for hybrid rocket application. - Abstract: Thermal characterizations of a novel solid fuel for hybrid rocket application, based on the paraffin wax blends with low density polyethylene (LDPE) concentration of 5% (SF-5) and 10% (SF-10) were conducted. Both the increased regression rate in comparison with the polymeric fuel, and the improved combustion efficiency in comparison with the pure paraffin fuel reveal that the blend fuels achieve higher combustion performance. The morphology of the shape stabilized paraffin wax/LDPE blends was characterized by the scanning electron microscopy (SEM). Although the SEM observation indicated the blends have uniform mixtures, they showed two degradation steps confirming the immiscibility of components in the crystalline phase from thermogravimetric analysis (TGA). The differential scanning calorimeter (DSC) results showed that the melting temperature of LDPE in the blends decreased with an increase of paraffin wax content. The decreasing total specific melting enthalpy of blended fuels with decreasing paraffin wax content is in fairly good agreement with the additive rule. In thermomechanical analysis (TMA), the linear coefficient of thermal expansion (LCTE) seems to decrease with an increase of LDPE loading, however, the loaded LDPE do merely affect the LCTE in case of the blends with low LDPE concentration. It was found that a blend of low concentration of LDPE with a relatively high concentration of paraffin wax can lead to a potential novel fuel for rocket application, a contrary case with respect to the field of phase change materials (PCM) where a blend of high concentration

  11. SOLID STATE ENERGY CONVERSION ALLIANCE DELPHI SOLID OXIDE FUEL CELL

    Energy Technology Data Exchange (ETDEWEB)

    Steven Shaffer; Sean Kelly; Subhasish Mukerjee; David Schumann; Gail Geiger; Kevin Keegan; John Noetzel; Larry Chick

    2003-12-08

    The objective of Phase I under this project is to develop a 5 kW Solid Oxide Fuel Cell power system for a range of fuels and applications. During Phase I, the following will be accomplished: Develop and demonstrate technology transfer efforts on a 5 kW stationary distributed power generation system that incorporates steam reforming of natural gas with the option of piped-in water (Demonstration System A). Initiate development of a 5 kW system for later mass-market automotive auxiliary power unit application, which will incorporate Catalytic Partial Oxidation (CPO) reforming of gasoline, with anode exhaust gas injected into an ultra-lean burn internal combustion engine. This technical progress report covers work performed by Delphi from January 1, 2003 to June 30, 2003, under Department of Energy Cooperative Agreement DE-FC-02NT41246. This report highlights technical results of the work performed under the following tasks: Task 1 System Design and Integration; Task 2 Solid Oxide Fuel Cell Stack Developments; Task 3 Reformer Developments; Task 4 Development of Balance of Plant (BOP) Components; Task 5 Manufacturing Development (Privately Funded); Task 6 System Fabrication; Task 7 System Testing; Task 8 Program Management; and Task 9 Stack Testing with Coal-Based Reformate.

  12. Nitrous Oxide/Paraffin Hybrid Rocket Engines

    Science.gov (United States)

    Zubrin, Robert; Snyder, Gary

    2010-01-01

    Nitrous oxide/paraffin (N2OP) hybrid rocket engines have been invented as alternatives to other rocket engines especially those that burn granular, rubbery solid fuels consisting largely of hydroxyl- terminated polybutadiene (HTPB). Originally intended for use in launching spacecraft, these engines would also be suitable for terrestrial use in rocket-assisted takeoff of small airplanes. The main novel features of these engines are (1) the use of reinforced paraffin as the fuel and (2) the use of nitrous oxide as the oxidizer. Hybrid (solid-fuel/fluid-oxidizer) rocket engines offer advantages of safety and simplicity over fluid-bipropellant (fluid-fuel/fluid-oxidizer) rocket en - gines, but the thrusts of HTPB-based hybrid rocket engines are limited by the low regression rates of the fuel grains. Paraffin used as a solid fuel has a regression rate about 4 times that of HTPB, but pure paraffin fuel grains soften when heated; hence, paraffin fuel grains can, potentially, slump during firing. In a hybrid engine of the present type, the paraffin is molded into a 3-volume-percent graphite sponge or similar carbon matrix, which supports the paraffin against slumping during firing. In addition, because the carbon matrix material burns along with the paraffin, engine performance is not appreciably degraded by use of the matrix.

  13. Modified computation of the nozzle damping coefficient in solid rocket motors

    Science.gov (United States)

    Liu, Peijin; Wang, Muxin; Yang, Wenjing; Gupta, Vikrant; Guan, Yu; Li, Larry K. B.

    2018-02-01

    In solid rocket motors, the bulk advection of acoustic energy out of the nozzle constitutes a significant source of damping and can thus influence the thermoacoustic stability of the system. In this paper, we propose and test a modified version of a historically accepted method of calculating the nozzle damping coefficient. Building on previous work, we separate the nozzle from the combustor, but compute the acoustic admittance at the nozzle entry using the linearized Euler equations (LEEs) rather than with short nozzle theory. We compute the combustor's acoustic modes also with the LEEs, taking the nozzle admittance as the boundary condition at the combustor exit while accounting for the mean flow field in the combustor using an analytical solution to Taylor-Culick flow. We then compute the nozzle damping coefficient via a balance of the unsteady energy flux through the nozzle. Compared with established methods, the proposed method offers competitive accuracy at reduced computational costs, helping to improve predictions of thermoacoustic instability in solid rocket motors.

  14. Investigation of Post-Flight Solid Rocket Booster Thermal Protection System

    Science.gov (United States)

    Nelson, Linda A.

    2006-01-01

    After every Shuttle mission, the Solid Rocket Boosters (SRBs) are recovered and observed for missing material. Most of the SRB is covered with a cork-based thermal protection material (MCC-l). After the most recent shuttle mission, STS-114, the forward section of the booster appeared to have been impacted during flight. The darkened fracture surfaces indicated that this might have occurred early in flight. The scope of the analysis included microscopic observations to assess the degree of heat effects and locate evidence of the impact source as well as chemical analysis of the fracture surfaces and recovered foreign material using Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy/Energy Dispersive Spectroscopy. The amount of heat effects and presence of soot products on the fracture surface indicated that the material was impacted prior to SRB re-entry into the atmosphere. Fragments of graphite fibers found on these fracture surfaces were traced to slag inside the Solid Rocket Motor (SRM) that forms during flight as the propellant is spent and is ejected throughout the descent of the SRB after separation. The direction of the impact mark matches with the likely trajectory of SRBs tumbling prior to re-entry.

  15. A Coupled Fluid-Structure Interaction Analysis of Solid Rocket Motor with Flexible Inhibitors

    Science.gov (United States)

    Yang, H. Q.; West, Jeff

    2014-01-01

    A capability to couple NASA production CFD code, Loci/CHEM, with CFDRC's structural finite element code, CoBi, has been developed. This paper summarizes the efforts in applying the installed coupling software to demonstrate/investigate fluid-structure interaction (FSI) between pressure wave and flexible inhibitor inside reusable solid rocket motor (RSRM). First a unified governing equation for both fluid and structure is presented, then an Eulerian-Lagrangian framework is described to satisfy the interfacial continuity requirements. The features of fluid solver, Loci/CHEM and structural solver, CoBi, are discussed before the coupling methodology of the solvers is described. The simulation uses production level CFD LES turbulence model with a grid resolution of 80 million cells. The flexible inhibitor is modeled with full 3D shell elements. Verifications against analytical solutions of structural model under steady uniform pressure condition and under dynamic condition of modal analysis show excellent agreements in terms of displacement distribution and eigen modal frequencies. The preliminary coupled result shows that due to acoustic coupling, the dynamics of one of the more flexible inhibitors shift from its first modal frequency to the first acoustic frequency of the solid rocket motor.

  16. Development of efficient finite elements for structural integrity analysis of solid rocket motor propellant grains

    International Nuclear Information System (INIS)

    Marimuthu, R.; Nageswara Rao, B.

    2013-01-01

    Solid propellant rocket motors (SRM) are regularly used in the satellite launch vehicles which consist of mainly three different structural materials viz., solid propellant, liner, and casing materials. It is essential to assess the structural integrity of solid propellant grains under the specified gravity, thermal and pressure loading conditions. For this purpose finite elements developed following the Herrmann formulation are: twenty node brick element (BH20), eight node quadrilateral plane strain element (PH8) and, eight node axi-symmetric solid of revolution element (AH8). The time-dependent nature of the solid propellant grains is taken into account utilizing the direct inverse method of Schepary to specify the effective Young's modulus and Poisson's ratio. The developed elements are tested considering various problems prior to implementation in the in-house software package (viz., Finite Element Analysis of STructures, FEAST). Several SRM configurations are analyzed to assess the structural integrity under different loading conditions. Finite element analysis results are found to be in good agreement with those obtained earlier from MARC software. -- Highlights: • Developed efficient Herrmann elements. • Accuracy of finite elements demonstrated solving several known solution problems. • Time dependent structural response obtained using the direct inverse method of Schepary. • Performed structural analysis of grains under gravity, thermal and pressure loads

  17. Understanding Kelvin-Helmholtz instability in paraffin-based hybrid rocket fuels

    Science.gov (United States)

    Petrarolo, Anna; Kobald, Mario; Schlechtriem, Stefan

    2018-04-01

    Liquefying fuels show higher regression rates than the classical polymeric ones. They are able to form, along their burning surface, a low viscosity and surface tension liquid layer, which can become unstable (Kelvin-Helmholtz instability) due to the high velocity gas flow in the fuel port. This causes entrainment of liquid droplets from the fuel surface into the oxidizer gas flow. To better understand the droplets entrainment mechanism, optical investigations on the combustion behaviour of paraffin-based hybrid rocket fuels in combination with gaseous oxygen have been conducted in the framework of this research. Combustion tests were performed in a 2D single-slab burner at atmospheric conditions. High speed videos were recorded and analysed with two decomposition techniques. Proper orthogonal decomposition (POD) and independent component analysis (ICA) were applied to the scalar field of the flame luminosity. The most excited frequencies and wavelengths of the wave-like structures characterizing the liquid melt layer were computed. The fuel slab viscosity and the oxidizer mass flow were varied to study their influence on the liquid layer instability process. The combustion is dominated by periodic, wave-like structures for all the analysed fuels. Frequencies and wavelengths characterizing the liquid melt layer depend on the fuel viscosity and oxidizer mass flow. Moreover, for very low mass flows, no wavelength peaks are detected for the higher viscosity fuels. This is important to better understand and predict the onset and development of the entrainment process, which is connected to the amplification of the longitudinal waves.

  18. Durable and Robust Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Hjalmarsson, Per; Knibbe, Ruth; Hauch, Anne

    project had as one of its’ overarching goals to improve durability and robustness of the Danish solid oxide fuel cells. The project focus was on cells and cell components suitable for SOFC operation in the temperature range 600 – 750 °C. The cells developed and/or studied in this project are intended......The solid oxide fuel cell (SOFC) is an attractive technology for the generation of electricity with high efficiency and low emissions. Risø DTU (now DTU Energy Conversion) works closely together with Topsoe Fuel Cell A/S in their effort to bring competitive SOFC systems to the market. This 2-year...... for use within the CHP (Combined Heat and Power) market segment with stationary power plants in the range 1 – 250 kWe in mind. Lowered operation temperature is considered a good way to improve the stack durability since corrosion of the interconnect plates in a stack is lifetime limiting at T > 750 °C...

  19. Solid Oxide Fuel Cell Systems PVL Line

    International Nuclear Information System (INIS)

    Shearer, Susan; Rush, Gregory

    2012-01-01

    In July 2010, Stark State College (SSC), received Grant DE-EE0003229 from the U.S. Department of Energy (DOE), Golden Field Office, for the development of the electrical and control systems, and mechanical commissioning of a unique 20kW scale high-pressure, high temperature, natural gas fueled Stack Block Test System (SBTS). SSC worked closely with subcontractor, Rolls-Royce Fuel Cell Systems (US) Inc. (RRFCS) over a 13 month period to successfully complete the project activities. This system will be utilized by RRFCS for pre-commercial technology development and training of SSC student interns. In the longer term, when RRFCS is producing commercial products, SSC will utilize the equipment for workforce training. In addition to DOE Hydrogen, Fuel Cells, and Infrastructure Technologies program funding, RRFCS internal funds, funds from the state of Ohio, and funding from the DOE Solid State Energy Conversion Alliance (SECA) program have been utilized to design, develop and commission this equipment. Construction of the SBTS (mechanical components) was performed under a Grant from the State of Ohio through Ohio's Third Frontier program (Grant TECH 08-053). This Ohio program supported development of a system that uses natural gas as a fuel. Funding was provided under the Department of Energy (DOE) Solid-state Energy Conversion Alliance (SECA) program for modifications required to test on coal synthesis gas. The subject DOE program provided funding for the electrical build, control system development and mechanical commissioning. Performance testing, which includes electrical commissioning, was subsequently performed under the DOE SECA program. Rolls-Royce Fuel Cell Systems is developing a megawatt-scale solid oxide fuel cell (SOFC) stationary power generation system. This system, based on RRFCS proprietary technology, is fueled with natural gas, and operates at elevated pressure. A critical success factor for development of the full scale system is the capability to

  20. Direct Carbon Fuel Cell System Utilizing Solid Carbonaceous Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Turgut Gur

    2010-04-30

    This 1-year project has achieved most of its objective and successfully demonstrated the viability of the fluidized bed direct carbon fuel cell (FB-DCFC) approach under development by Direct Carbon technologies, LLC, that utilizes solid carbonaceous fuels for power generation. This unique electrochemical technology offers high conversion efficiencies, produces proportionately less CO{sub 2} in capture-ready form, and does not consume or require water for gasification. FB-DCFC employs a specialized solid oxide fuel cell (SOFC) arrangement coupled to a Boudouard gasifier where the solid fuel particles are fluidized and reacted by the anode recycle gas CO{sub 2}. The resulting CO is electrochemically oxidized at the anode. Anode supported SOFC structures employed a porous Ni cermet anode layer, a dense yttria stabilized zirconia membrane, and a mixed conducting porous perovskite cathode film. Several kinds of untreated solid fuels (carbon and coal) were tested in bench scale FBDCFC prototypes for electrochemical performance and stability testing. Single cells of tubular geometry with active areas up to 24 cm{sup 2} were fabricated. The cells achieved high power densities up to 450 mW/cm{sup 2} at 850 C using a low sulfur Alaska coal char. This represents the highest power density reported in the open literature for coal based DCFC. Similarly, power densities up to 175 mW/cm{sup 2} at 850 C were demonstrated with carbon. Electrical conversion efficiencies for coal char were experimentally determined to be 48%. Long-term stability of cell performance was measured under galvanostatic conditions for 375 hours in CO with no degradation whatsoever, indicating that carbon deposition (or coking) does not pose any problems. Similar cell stability results were obtained in coal char tested for 24 hours under galvanostatic conditions with no sign of sulfur poisoning. Moreover, a 50-cell planar stack targeted for 1 kW output was fabricated and tested in 95% CO (balance CO{sub 2

  1. SOLID STATE ENERGY CONVERSION ALLIANCE DELPHI SOLID OXIDE FUEL CELL

    Energy Technology Data Exchange (ETDEWEB)

    Steven Shaffer; Sean Kelly; Subhasish Mukerjee; David Schumann; Gail Geiger; Kevin Keegan; Larry Chick

    2004-05-07

    The objective of this project is to develop a 5 kW Solid Oxide Fuel Cell power system for a range of fuels and applications. During Phase I, the following will be accomplished: Develop and demonstrate technology transfer efforts on a 5 kW stationary distributed power generation system that incorporates steam reforming of natural gas with the option of piped-in water (Demonstration System A). Initiate development of a 5 kW system for later mass-market automotive auxiliary power unit application, which will incorporate Catalytic Partial Oxidation (CPO) reforming of gasoline, with anode exhaust gas injected into an ultra-lean burn internal combustion engine. This technical progress report covers work performed by Delphi from July 1, 2003 to December 31, 2003, under Department of Energy Cooperative Agreement DE-FC-02NT41246. This report highlights technical results of the work performed under the following tasks: Task 1 System Design and Integration; Task 2 Solid Oxide Fuel Cell Stack Developments; Task 3 Reformer Developments; Task 4 Development of Balance of Plant (BOP) Components; Task 5 Manufacturing Development (Privately Funded); Task 6 System Fabrication; Task 7 System Testing; Task 8 Program Management; Task 9 Stack Testing with Coal-Based Reformate; and Task 10 Technology Transfer from SECA CORE Technology Program. In this reporting period, unless otherwise noted Task 6--System Fabrication and Task 7--System Testing will be reported within Task 1 System Design and Integration. Task 8--Program Management, Task 9--Stack Testing with Coal Based Reformate, and Task 10--Technology Transfer from SECA CORE Technology Program will be reported on in the Executive Summary section of this report.

  2. Tubular solid oxide fuel cell development program

    Energy Technology Data Exchange (ETDEWEB)

    Ray, E.R.; Cracraft, C.

    1995-12-31

    This paper presents an overview of the Westinghouse Solid Oxide Fuel Cell (SOFC) development activities and current program status. The Westinghouse goal is to develop a cost effective cell that can operate for 50,000 to 100,000 hours. Progress toward this goal will be discussed and test results presented for multiple single cell tests which have now successfully exceeded 56,000 hours of continuous power operation at temperature. Results of development efforts to reduce cost and increase power output of tubular SOFCs are described.

  3. Complex plasmochemical processing of solid fuel

    Directory of Open Access Journals (Sweden)

    Vladimir Messerle

    2012-12-01

    Full Text Available Technology of complex plasmaochemical processing of solid fuel by Ecibastuz bituminous and Turgay brown coals is presented. Thermodynamic and experimental study of the technology was fulfilled. Use of this technology allows producing of synthesis gas from organic mass of coal and valuable components (technical silicon, ferrosilicon, aluminum and silicon carbide and microelements of rare metals: uranium, molybdenum, vanadium etc. from mineral mass of coal. Produced a high-calorific synthesis gas can be used for methanol synthesis, as high-grade reducing gas instead of coke, as well as energy gas in thermal power plants.

  4. Solid oxide fuel cell field trial evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Wilcox, C.P.; Winstanley, R.; Nietsch, T.; Smith, C.; Knight, R.; Seymore, C.

    2000-07-01

    This report focuses on issues relating to a field trial of a solid oxide fuel cell (SOFC). Aspects examined include markets for SOFC systems, the choice of systems for demonstration in year 2002, the assessment of industrial interest, and evaluation and ranking of candidate systems. The identification and evaluation of interest in field trials, the estimation of the capital and running costs of a field trial, and identification of the benefits to the UK and barriers to implementation of SOFC systems are discussed. (UK)

  5. The development of reactive fuel grains for pyrophoric relight of in-space hybrid rocket thrusters

    Science.gov (United States)

    Steiner, Matthew Wellington

    This study presents and investigates a novel hybrid fuel grain that reacts pyrophorically with gaseous oxidizer to achieve restart of a hybrid rocket motor propulsion system while reducing cost and handling concerns. This reactive fuel grain (RFG) relies on the pyrophoric nature of finely divided metal particles dispersed in a solid dicyclopentadiene (DCPD) binder, which has been shown to encapsulate air-sensitive additives until they are exposed to combustion gases. An RFG is thus effectively inert in open air in the absence of an ignition source, though the particles encapsulated within remain pyrophoric. In practice, this means that an RFG that is ignited in the vacuum of space and then extinguished will expose unoxidized pyrophoric particles, which can be used to generate sufficient heat to relight the propellant when oxidizer is flowed. The experiments outlined in this work aim to develop a suitable pyrophoric material for use in an RFG, demonstrate pyrophoric relight, and characterize performance under conditions relevant to a hybrid rocket thruster. Magnesium, lithium, calcium, and an alloy of titanium, chromium, and manganese (TiCrMn) were investigated to determine suitability of pure metals as RFG additives. Additionally, aluminum hydride (AlH3), lithium aluminum hydride (LiAlH4), lithium borohydride (LiBH4), and magnesium hydride (MgH2) were investigated to determine suitability of metals hydrides as RFG additives or as precursors for pure-metal RFG additives. Pyrophoric metals have been previously investigated as additives for increasing the regression rate of hybrid fuels, but to the author's knowledge, these materials have not been specifically investigated for their ability to ignite a propellant pyrophorically. Commercial research-grade metals were obtained as coarse powders, then ball-milled to attempt to reduce particle size below a critical diameter needed for pyrophoricity. Magnesium hydride was ball-milled and then cycled in a hydride cycling

  6. Indirect and direct methods for measuring a dynamic throat diameter in a solid rocket motor

    Science.gov (United States)

    Colbaugh, Lauren

    In a solid rocket motor, nozzle throat erosion is dictated by propellant composition, throat material properties, and operating conditions. Throat erosion has a significant effect on motor performance, so it must be accurately characterized to produce a good motor design. In order to correlate throat erosion rate to other parameters, it is first necessary to know what the throat diameter is throughout a motor burn. Thus, an indirect method and a direct method for determining throat diameter in a solid rocket motor are investigated in this thesis. The indirect method looks at the use of pressure and thrust data to solve for throat diameter as a function of time. The indirect method's proof of concept was shown by the good agreement between the ballistics model and the test data from a static motor firing. The ballistics model was within 10% of all measured and calculated performance parameters (e.g. average pressure, specific impulse, maximum thrust, etc.) for tests with throat erosion and within 6% of all measured and calculated performance parameters for tests without throat erosion. The direct method involves the use of x-rays to directly observe a simulated nozzle throat erode in a dynamic environment; this is achieved with a dynamic calibration standard. An image processing algorithm is developed for extracting the diameter dimensions from the x-ray intensity digital images. Static and dynamic tests were conducted. The measured diameter was compared to the known diameter in the calibration standard. All dynamic test results were within +6% / -7% of the actual diameter. Part of the edge detection method consists of dividing the entire x-ray image by an average pixel value, calculated from a set of pixels in the x-ray image. It was found that the accuracy of the edge detection method depends upon the selection of the average pixel value area and subsequently the average pixel value. An average pixel value sensitivity analysis is presented. Both the indirect

  7. Radiometric probe design for the measurement of heat flux within a solid rocket motor nozzle

    Science.gov (United States)

    Goldey, Charles L.; Laughlin, William T.; Popper, Leslie A.

    1996-11-01

    Improvements to solid rocket motor (SRM) nozzle designs and material performance is based on the ability to instrument motors during test firings to understand the internal combustion processes and the response of nozzle components to the severe heating environment. Measuring the desired parameters is very difficult because the environment inside of an SRM is extremely severe. Instrumentation can be quickly destroyed if exposed to the internal rocket motor environment. An optical method is under development to quantify the heating of the internal nozzle surface. A radiometric probe designed for measuring the thermal response and material surface recession within a nozzle while simultaneously confining the combustion products has been devised and demonstrated. As part of the probe design, optical fibers lead to calibrated detectors that measure the interior nozzle thermal response. This two color radiometric measurement can be used for a direct determination of the total heat flux impinging on interior nozzle surfaces. This measurement has been demonstrated using a high power CO2 laser to simulate SRM nozzle heating conditions on carbon phenolic and graphite phenolic materials.

  8. Solid oxide fuel cells and hydrogen production

    International Nuclear Information System (INIS)

    Dogan, F.

    2009-01-01

    'Full text': A single-chamber solid oxide fuel cell (SC-SOFC), operating in a mixture of fuel and oxidant gases, provides several advantages over the conventional SOFC such as simplified cell structure (no sealing required). SC-SOFC allows using a variety of fuels without carbon deposition by selecting appropriate electrode materials and cell operating conditions. The operating conditions of single chamber SOFC was studied using hydrocarbon-air gas mixtures for a cell composed of NiO-YSZ / YSZ / LSCF-Ag. The cell performance and catalytic activity of the anode was measured at various gas flow rates. The results showed that the open-circuit voltage and the power density increased as the gas flow rate increased. Relatively high power densities up to 660 mW/cm 2 were obtained in a SC-SOFC using porous YSZ electrolytes instead of dense electrolytes required for operation of a double chamber SOFC. In addition to propane- or methane-air mixtures as a fuel source, the cells were also tested in a double chamber configuration using hydrogen-air mixtures by controlling the hydrogen/air ratio at the cathode and the anode. Simulation of single chamber conditions in double chamber configurations allows distinguishing and better understanding of the electrode reactions in the presence of mixed gases. Recent research efforts; the effect of hydrogen-air mixtures as a fuel source on the performance of anode and cathode materials in single-chamber and double-chamber SOFC configurations,will be presented. The presentation will address a review on hydrogen production by utilizing of reversible SOFC systems. (author)

  9. Space Shuttle Redesigned Solid Rocket Motor nozzle natural frequency variations with burn time

    Science.gov (United States)

    Lui, C. Y.; Mason, D. R.

    1991-01-01

    The effects of erosion and thermal degradation on the Space Shuttle Redesigned Solid Rocket Motor (RSRM) nozzle's structural dynamic characteristics were analytically evaluated. Also considered was stiffening of the structure due to internal pressurization. A detailed NASTRAN finite element model of the nozzle was developed and used to evaluate the influence of these effects at several discrete times during motor burn. Methods were developed for treating erosion and thermal degradation, and a procedure was developed to account for internal pressure stiffening using differential stiffness matrix techniques. Results were verified using static firing test accelerometer data. Fast Fourier Transform and Maximum Entropy Method techniques were applied to the data to generate waterfall plots which track modal frequencies with burn time. Results indicate that the lower frequency nozzle 'vectoring' modes are only slightly affected by erosion, thermal effects and internal pressurization. The higher frequency shell modes of the nozzle are, however, significantly reduced.

  10. Test data from small solid propellant rocket motor plume measurements (FA-21)

    Science.gov (United States)

    Hair, L. M.; Somers, R. E.

    1976-01-01

    A program is described for obtaining a reliable, parametric set of measurements in the exhaust plumes of solid propellant rocket motors. Plume measurements included pressures, temperatures, forces, heat transfer rates, particle sampling, and high-speed movies. Approximately 210,000 digital data points and 15,000 movie frames were acquired. Measurements were made at points in the plumes via rake-mounted probes, and on the surface of a large plate impinged by the exhaust plume. Parametric variations were made in pressure altitude, propellant aluminum loading, impinged plate incidence angle and distance from nozzle exit to plate or rake. Reliability was incorporated by continual use of repeat runs. The test setup of the various hardware items is described along with an account of test procedures. Test results and data accuracy are discussed. Format of the data presentation is detailed. Complete data are included in the appendix.

  11. Multiple time scale analysis of pressure oscillations in solid rocket motors

    Science.gov (United States)

    Ahmed, Waqas; Maqsood, Adnan; Riaz, Rizwan

    2018-03-01

    In this study, acoustic pressure oscillations for single and coupled longitudinal acoustic modes in Solid Rocket Motor (SRM) are investigated using Multiple Time Scales (MTS) method. Two independent time scales are introduced. The oscillations occur on fast time scale whereas the amplitude and phase changes on slow time scale. Hopf bifurcation is employed to investigate the properties of the solution. The supercritical bifurcation phenomenon is observed for linearly unstable system. The amplitude of the oscillations result from equal energy gain and loss rates of longitudinal acoustic modes. The effect of linear instability and frequency of longitudinal modes on amplitude and phase of oscillations are determined for both single and coupled modes. For both cases, the maximum amplitude of oscillations decreases with the frequency of acoustic mode and linear instability of SRM. The comparison of analytical MTS results and numerical simulations demonstrate an excellent agreement.

  12. Structural optimization of an alternate design for the Space Shuttle solid rocket booster field joint

    Science.gov (United States)

    Barthelemy, Jean-Francois M.; Rogers, James L., Jr.; Chang, Kwan J.

    1987-01-01

    A structural optimization procedure is used to determine the shape of an alternate design for the Shuttle's solid rocket booster field joint. In contrast to the tang and clevis design of the existing joint, this alternate design consists of two flanges bolted together. Configurations with 150 studs of 1 1/8 in diameter and 135 studs of 1 3/16 in diameter are considered. Using a nonlinear programming procedure, the joint weight is minimized under constraints on either von Mises or maximum normal stresses, joint opening and geometry. The procedure solves the design problem by replacing it by a sequence of approximate (convex) subproblems; the pattern of contact between the joint halves is determined every few cycles by a nonlinear displacement analysis. The minimum weight design has 135 studs of 1 3/16 in diameter and is designed under constraints on normal stresses. It weighs 1144 lb per joint more than the current tang and clevis design.

  13. Lightweight structural design of a bolted case joint for the space shuttle solid rocket motor

    Science.gov (United States)

    Dorsey, John T.; Stein, Peter A.; Bush, Harold G.

    1988-01-01

    The structural design of a bolted joint with a static face seal which can be used to join Space Shuttle Solid Rocket Motor (SRM) case segments is given. Results from numerous finite element parametric studies indicate that the bolted joint meets the design requirement of preventing joint opening at the O-ring locations during SRM pressurization. A final design recommended for further development has the following parameters: 180 one-in.-diam. studs, stud centerline offset of 0.5 in radially inward from the shell wall center line, flange thickness of 0.75 in, bearing plate thickness of 0.25 in, studs prestressed to 70 percent of ultimate load, and the intermediate alcove. The design has a mass penalty of 1096 lbm, which is 164 lbm greater than the currently proposed capture tang redesign.

  14. Computation of turbulent reacting flow in a solid-propellant ducted rocket

    Science.gov (United States)

    Chao, Yei-Chin; Chou, Wen-Fuh; Liu, Sheng-Shyang

    1995-05-01

    A mathematical model for computation of turbulent reacting flows is developed under general curvilinear coordinate systems. An adaptive, streamline grid system is generated to deal with the complex flow structures in a multiple-inlet solid-propellant ducted rocket (SDR) combustor. General tensor representations of the k-epsilon and algebraic stress (ASM) turbulence models are derived in terms of contravariant velocity components, and modification caused by the effects of compressible turbulence is also included in the modeling. The clipped Gaussian probability density function is incorporated in the combustion model to account for fluctuations of properties. Validation of the above modeling is first examined by studying mixing and reacting characteristics in a confined coaxial-jet problem. This is followed by study of nonreacting and reacting SDR combustor flows. The results show that Gibson and Launder's ASM incorporated with Sarkar's modification for compressible turbulence effects based on the general curvilinear coordinate systems yields the most satisfactory prediction for this complicated SDR flowfield.

  15. Multisized Inert Particle Loading for Solid Rocket Axial Combustion Instability Suppression

    Directory of Open Access Journals (Sweden)

    David R. Greatrix

    2012-01-01

    Full Text Available In the present investigation, various factors and trends, related to the usage of two or more sets of inert particles comprised of the same material (nominally aluminum but at different diameters for the suppression of axial shock wave development, are numerically predicted for a composite-propellant cylindrical-grain solid rocket motor. The limit pressure wave magnitudes at a later reference time in a given pulsed firing simulation run are collected for a series of runs at different particle sizes and loading distributions and mapped onto corresponding attenuation trend charts. The inert particles’ presence in the central core flow is demonstrated to be an effective means of instability symptom suppression, in correlating with past experimental successes in the usage of particles. However, the predicted results of this study suggest that one needs to be careful when selecting more than one size of particle for a given motor application.

  16. Scale effects on quasi-steady solid rocket internal ballistic behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Greatrix, D. R. [Department of Aerospace Engineering, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B2K3 (Canada)

    2010-11-15

    The ability to predict with some accuracy a given solid rocket motor's performance before undertaking one or several costly experimental test firings is important. On the numerical prediction side, as various component models evolve, their incorporation into an overall internal ballistics simulation program allows for new motor firing simulations to take place, which in turn allows for updated comparisons to experimental firing data. In the present investigation, utilizing an updated simulation program, the focus is on quasi-steady performance analysis and scale effects (influence of motor size). The predicted effects of negative/positive erosive burning and propellant/casing deflection, as tied to motor size, on a reference cylindrical-grain motor's internal ballistics, are included in this evaluation. Propellant deflection has only a minor influence on the reference motor's internal ballistics, regardless of motor size. Erosive burning, on the other hand, is distinctly affected by motor scale. (author)

  17. Simulation of Axial Combustion Instability Development and Suppression in Solid Rocket Motors

    Directory of Open Access Journals (Sweden)

    David R. Greatrix

    2009-03-01

    Full Text Available In the design of solid-propellant rocket motors, the ability to understand and predict the expected behaviour of a given motor under unsteady conditions is important. Research towards predicting, quantifying, and ultimately suppressing undesirable strong transient axial combustion instability symptoms necessitates a comprehensive numerical model for internal ballistic simulation under dynamic flow and combustion conditions. An updated numerical model incorporating recent developments in predicting negative and positive erosive burning, and transient, frequency-dependent combustion response, in conjunction with pressure-dependent and acceleration-dependent burning, is applied to the investigation of instability-related behaviour in a small cylindrical-grain motor. Pertinent key factors, like the initial pressure disturbance magnitude and the propellant's net surface heat release, are evaluated with respect to their influence on the production of instability symptoms. Two traditional suppression techniques, axial transitions in grain geometry and inert particle loading, are in turn evaluated with respect to suppressing these axial instability symptoms.

  18. Internal Flow Simulation of Enhanced Performance Solid Rocket Booster for the Space Transportation System

    Science.gov (United States)

    Ahmad, Rashid A.; McCool, Alex (Technical Monitor)

    2001-01-01

    An enhanced performance solid rocket booster concept for the space shuttle system has been proposed. The concept booster will have strong commonality with the existing, proven, reliable four-segment Space Shuttle Reusable Solid Rocket Motors (RSRM) with individual component design (nozzle, insulator, etc.) optimized for a five-segment configuration. Increased performance is desirable to further enhance safety/reliability and/or increase payload capability. Performance increase will be achieved by adding a fifth propellant segment to the current four-segment booster and opening the throat to accommodate the increased mass flow while maintaining current pressure levels. One development concept under consideration is the static test of a "standard" RSRM with a fifth propellant segment inserted and appropriate minimum motor modifications. Feasibility studies are being conducted to assess the potential for any significant departure in component performance/loading from the well-characterized RSRM. An area of concern is the aft motor (submerged nozzle inlet, aft dome, etc.) where the altered internal flow resulting from the performance enhancing features (25% increase in mass flow rate, higher Mach numbers, modified subsonic nozzle contour) may result in increased component erosion and char. To assess this issue and to define the minimum design changes required to successfully static test a fifth segment RSRM engineering test motor, internal flow studies have been initiated. Internal aero-thermal environments were quantified in terms of conventional convective heating and discrete phase alumina particle impact/concentration and accretion calculations via Computational Fluid Dynamics (CFD) simulation. Two sets of comparative CFD simulations of the RSRM and the five-segment (IBM) concept motor were conducted with CFD commercial code FLUENT. The first simulation involved a two-dimensional axi-symmetric model of the full motor, initial grain RSRM. The second set of analyses

  19. Real-Time Inhibitor Recession Measurements in Two Space Shuttle Reusable Solid Rocket Motors

    Science.gov (United States)

    McWhorter, B. B.; Ewing, M. E.; Bolton, D. E.; Albrechtsen, K. U.; Earnest, T. E.; Noble, T. C.; Longaker, M.

    2003-01-01

    Real-time internal motor insulation char line recession measurements have been evaluated for two full-scale static tests of the Space Shuttle Reusable Solid Rocket Motor (RSRM). These char line recession measurements were recorded on the forward facing propellant grain inhibitors to better understand the thermal performance of these inhibitors. The RSRM propellant grain inhibitors are designed to erode away during motor operation, thus making it difficult to use post-fire observations to determine inhibitor thermal performance. Therefore, this new internal motor instrumentation is invaluable in establishing an accurate understanding of inhibitor recession versus motor operation time. The data for the first test was presented at the 37th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (AIAA 2001-3280) in July 2001. Since that time, a second full scale static test has delivered additional real-time data on inhibitor thermal performance. The evaluation of this data is presented in this paper. The second static test, in contrast to the first test, used a slightly different arrangement of instrumentation in the inhibitors. This instrumentation has yielded a better understanding of the inhibitor time dependent inboard tip recession. Graphs of inhibitor recession profiles with time are presented. Inhibitor thermal ablation models have been created from theoretical principals. The model predictions compare favorably with data from both tests. This verified modeling effort is important to support new inhibitor designs for a five segment Space Shuttle solid rocket motor. The internal instrumentation project on RSRM static tests is providing unique opportunities for other real-time internal motor measurements that could not otherwise be directly quantified.

  20. Elastomeric Thermal Insulation Design Considerations in Long, Aluminized Solid Rocket Motors

    Science.gov (United States)

    Martin, Heath T.

    2017-01-01

    An all-new sounding rocket was designed at NASA's Marshall Space Flight Center that featured an aft finocyl, aluminized solid propellant grain and silica-filled ethylene-propylene-diene monomer (SFEPDM) internal insulation. Upon the initial static firing of the first of this new design, the solid rocket motor (SRM) case failed thermally just upstream of the aft closure early in the burn time. Subsequent fluid modeling indicated that the high-velocity combustion-product jets emanating from the fin-slots in the propellant grain were likely inducing a strongly swirling flow, thus substantially increasing the severity of the convective environment on the exposed portion of the SFEPDM insulation in this region. The aft portion of the fin-slots in another of the motors were filled with propellant to eliminate the possibility of both direct jet impingement on the exposed SFEPDM and the appearance of strongly swirling flow in the aft region of the motor. When static-fired, this motor's case still failed in the same axial location, and, though somewhat later than for the first static firing, still in less than 1/3rd of the desired burn duration. These results indicate that the extreme material decomposition rates of the SFEPDM in this application are not due to gas-phase convection or shear but rather to interactions with burning aluminum or alumina slag. Further comparisons with between SFEPDM performance in this design and that in other hot-fire tests provide insight into the mechanisms of SFEPDM decomposition in SRM aft domes that can guide the upcoming redesign effort, as well as other future SRM designs. These data also highlight the current limitations of modeling elastomeric insulators solely with diffusion-controlled, gas-phase thermochemistry in SRM regions with significant viscous shear and/or condense-phase impingement or flow.

  1. Computational Fluid Dynamics Simulation of Combustion Instability in Solid Rocket Motor : Implementation of Pressure Coupled Response Function

    OpenAIRE

    S. Saha; D. Chakraborty

    2016-01-01

    Combustion instability in solid propellant rocket motor is numerically simulated by implementing propellant response function with quasi steady homogeneous one dimensional formulation. The convolution integral of propellant response with pressure history is implemented through a user defined function in commercial computational fluid dynamics software. The methodology is validated against literature reported motor test and other simulation results. Computed amplitude of pressure fluctuations ...

  2. Experimental evaluation of hybrid propulsion rocket engine operating with paraffin fuel grain and gaseous oxygen

    OpenAIRE

    Genivaldo Pimenta dos Santos

    2014-01-01

    In the last decade the hybrid propulsion has been considering as a viable alternative of chemical energy conversion stored in propellants into kinetic energy. This energy is applied in propulsive systems of manned platforms, maneuvering procedures and even in the repositioning process of micro satellites. It presents attractive features and good balance between performance and environmental impact. Paraffin based grains are the hybrid solid fuels appointed as polymeric fuel substitute. The li...

  3. Fixed bed gasification of solid biomass fuels

    Energy Technology Data Exchange (ETDEWEB)

    Haavisto, I [Condens Oy, Haemeenlinna (Finland)

    1997-12-31

    Fixed bed biomass gasifiers are feasible in the effect range of 100 kW -10 MW. Co-current gasification is available only up to 1 MW for technical reasons. Counter-current gasifiers have been used in Finland and Sweden for 10 years in gasification heating plants, which are a combination of a gasifier and an oil boiler. The plants have proved to have a wide control range, flexible and uncomplicated unmanned operation and an excellent reliability. Counter-current gasifiers can be applied for new heating plants or for converting existing oil and natural gas boilers into using solid fuels. There is a new process development underway, aiming at motor use of the producer gas. The development work involves a new, more flexible cocurrent gasifier and a cleaning step for the counter-current producer gas. (orig.)

  4. Fixed bed gasification of solid biomass fuels

    Energy Technology Data Exchange (ETDEWEB)

    Haavisto, I. [Condens Oy, Haemeenlinna (Finland)

    1996-12-31

    Fixed bed biomass gasifiers are feasible in the effect range of 100 kW -10 MW. Co-current gasification is available only up to 1 MW for technical reasons. Counter-current gasifiers have been used in Finland and Sweden for 10 years in gasification heating plants, which are a combination of a gasifier and an oil boiler. The plants have proved to have a wide control range, flexible and uncomplicated unmanned operation and an excellent reliability. Counter-current gasifiers can be applied for new heating plants or for converting existing oil and natural gas boilers into using solid fuels. There is a new process development underway, aiming at motor use of the producer gas. The development work involves a new, more flexible cocurrent gasifier and a cleaning step for the counter-current producer gas. (orig.)

  5. Evaluation of Solid Rocket Motor Component Data Using a Commercially Available Statistical Software Package

    Science.gov (United States)

    Stefanski, Philip L.

    2015-01-01

    Commercially available software packages today allow users to quickly perform the routine evaluations of (1) descriptive statistics to numerically and graphically summarize both sample and population data, (2) inferential statistics that draws conclusions about a given population from samples taken of it, (3) probability determinations that can be used to generate estimates of reliability allowables, and finally (4) the setup of designed experiments and analysis of their data to identify significant material and process characteristics for application in both product manufacturing and performance enhancement. This paper presents examples of analysis and experimental design work that has been conducted using Statgraphics®(Registered Trademark) statistical software to obtain useful information with regard to solid rocket motor propellants and internal insulation material. Data were obtained from a number of programs (Shuttle, Constellation, and Space Launch System) and sources that include solid propellant burn rate strands, tensile specimens, sub-scale test motors, full-scale operational motors, rubber insulation specimens, and sub-scale rubber insulation analog samples. Besides facilitating the experimental design process to yield meaningful results, statistical software has demonstrated its ability to quickly perform complex data analyses and yield significant findings that might otherwise have gone unnoticed. One caveat to these successes is that useful results not only derive from the inherent power of the software package, but also from the skill and understanding of the data analyst.

  6. Flight Investigation of the Performance of a Two-stage Solid-propellant Nike-deacon (DAN) Meteorological Sounding Rocket

    Science.gov (United States)

    Heitkotter, Robert H

    1956-01-01

    A flight investigation of two Nike-Deacon (DAN) two-stage solid-propellant rocket vehicles indicated satisfactory performance may be expected from the DAN meteorological sounding rocket. Peak altitudes of 356,000 and 350,000 feet, respectively, were recorded for the two flight tests when both vehicles were launched from sea level at an elevation angle of 75 degrees. Performance calculations based on flight-test results show that altitudes between 358,000 feet and 487,000 feet may be attained with payloads varying between 60 pounds and 10 pounds.

  7. Reviews on Solid Oxide Fuel Cell Technology

    Directory of Open Access Journals (Sweden)

    Apinan Soottitantawat

    2009-02-01

    Full Text Available Solid Oxide Fuel Cell (SOFC is one type of high temperature fuel cell that appears to be one of the most promising technology to provide the efficient and clean energy production for wide range of applications (from small units to large scale power plants. This paper reviews the current status and related researches on SOFC technologies. In details, the research trend for the development of SOFC components(i.e. anode, electrolyte, cathode, and interconnect are presented. Later, the current important designs of SOFC (i.e. Seal-less Tubular Design, Segmented Cell in Series Design, Monolithic Design and Flat Plate Design are exampled. In addition, the possible operations of SOFC (i.e. external reforming, indirect internal reforming, and direct internal reforming are discussed. Lastly, the research studies on applications of SOFCs with co-generation (i.e. SOFC with Combined Heat and Power (SOFC-CHP, SOFC with Gas Turbine (SOFC-GT and SOFC with chemical production are given.

  8. Learning curves for solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Rivera-Tinoco, R.; Schoots, K. [Energy research Centre of the Netherlands (Netherlands). Policy Studies; Zwaan, B.C.C. van der [Energy research Centre of the Netherlands (Netherlands). Policy Studies; Columbia Univ., New York City, NY (United States). Lenfest Center for Sustainable Energy

    2010-07-01

    We present learning curves for solid oxide fuel cells (SOFCs) and combined heat and power (CHP) SOFC systems with an electric capacity between 1 and 250 kW. On the basis of the cost breakdown of production cost data from fuel cell manufacturers, we developed a bottom-up model that allows for determining overall manufacturing costs from their respective cost components, among which material, energy, labor, and capital charges. The results obtained from our model prove to deviate by at most 13% from total cost figures quoted in the literature. For the early pilot stage of development, we find for SOFC manufacturing a learning rate between 14% and 17%, and for total SOFC system fabrication between 16% and 19%. We argue that the corresponding cost reductions result largely from learning-by-searching effects (R and D) rather than learning-by-doing. When considering a longer time frame that includes the early commercial production stage, we find learning rates between 14% and 39%, which represent a mix of phenomena such as learning-by-doing, learning-by-searching, economies-of-scale and automation. (orig.)

  9. Medium-temperature solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Maffei, N.; Kuriakose, A.K. [Natural Resources Canada, Ottawa, ON (Canada). Materials Technology Lab

    2000-07-01

    The Materials Technology Laboratory (MTL) of Natural Resources Canada has been conducting research on the development of a solid oxide fuel cell (SOFC) for the past decade. Fuel cells convert chemical energy directly into electric energy in an efficient and environmentally friendly manner. SOFCs are considered to be good stationary power sources for commercial and residential applications and will likely be commercialized in the near future. The research at MTL has focused on the development of new electrolytes for use in SOFCs. In the course of this research, monolithic planar single cell SOFCs based on doubly doped ceria and lanthanum gallate have been fabricated and tested at 700 degrees C. This paper compared the performance characteristics of both these systems. The data suggested the presence of a significant electronic conductivity in the SOFC incorporating doubly doped ceria, resulting in lower than expected voltage output. The stability of the SOFC, however, did not appear to be negatively affected. The lanthanum gallate based SOFC performed well. It was concluded that reducing the operating temperature of SOFCs would improve their reliability and enhance their operating life. First generation commercial SOFCs will use a zirconium oxide-based electrolytes while second generation units might possibly use ceria-based and/or lanthanum gallate electrolytes. 24 refs., 6 figs.

  10. Nanostructured Solid Oxide Fuel Cell Electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Sholklapper, Tal Zvi [Univ. of California, Berkeley, CA (United States)

    2007-01-01

    The ability of Solid Oxide Fuel Cells (SOFC) to directly and efficiently convert the chemical energy in hydrocarbon fuels to electricity places the technology in a unique and exciting position to play a significant role in the clean energy revolution. In order to make SOFC technology cost competitive with existing technologies, the operating temperatures have been decreased to the range where costly ceramic components may be substituted with inexpensive metal components within the cell and stack design. However, a number of issues have arisen due to this decrease in temperature: decreased electrolyte ionic conductivity, cathode reaction rate limitations, and a decrease in anode contaminant tolerance. While the decrease in electrolyte ionic conductivities has been countered by decreasing the electrolyte thickness, the electrode limitations have remained a more difficult problem. Nanostructuring SOFC electrodes addresses the major electrode issues. The infiltration method used in this dissertation to produce nanostructure SOFC electrodes creates a connected network of nanoparticles; since the method allows for the incorporation of the nanoparticles after electrode backbone formation, previously incompatible advanced electrocatalysts can be infiltrated providing electronic conductivity and electrocatalysis within well-formed electrolyte backbones. Furthermore, the method is used to significantly enhance the conventional electrode design by adding secondary electrocatalysts. Performance enhancement and improved anode contamination tolerance are demonstrated in each of the electrodes. Additionally, cell processing and the infiltration method developed in conjunction with this dissertation are reviewed.

  11. Solid Oxide Fuel Cells Canada (SOFCC)

    International Nuclear Information System (INIS)

    Birss, V.; Borglum, B.

    2006-01-01

    Vision: To enhance co-ordination and to ensure sustainable funding of research, development, and commercialization of solid oxide fuel cells and related technologies in Canada in order to create products that serve the world. Current Research Areas of Investigation: Mission: To provide cleaner air, reduce CO 2 emissions, better utilize fuel resources, increase economic prosperity, and enhance the quality of life in Canada and the world by enabling and accelerating development of the Canadian SOFC industry. To achieve this, we will: 1. Establish national priorities for the research, development, design, demonstration, and the innovation process; commercialization of SOFC and related technologies; 2. Develop a strategy to produce commercial products within 5 years; 3. Co-ordinate activities as one integrated Canada-wide initiative; 4. Facilitate effective access to funding by providing a venue for funders to directly participate in; 5. Provide an integrating and interdisciplinary function to maximize the collective knowledge, expertise, and capacity of the alliance partners; 6. Maintain strategic relevance within an ever changing global context by providing high-quality intelligence. (author)

  12. Quantification of transformation products of rocket fuel unsymmetrical dimethylhydrazine in soils using SPME and GC-MS.

    Science.gov (United States)

    Bakaikina, Nadezhda V; Kenessov, Bulat; Ul'yanovskii, Nikolay V; Kosyakov, Dmitry S

    2018-07-01

    Determination of transformation products (TPs) of rocket fuel unsymmetrical dimethylhydrazine (UDMH) in soil is highly important for environmental impact assessment of the launches of heavy space rockets from Kazakhstan, Russia, China and India. The method based on headspace solid-phase microextraction (HS SPME) and gas chromatography-mass spectrometry is advantageous over other known methods due to greater simplicity and cost efficiency. However, accurate quantification of these analytes using HS SPME is limited by the matrix effect. In this research, we proposed using internal standard and standard addition calibrations to achieve proper combination of accuracies of the quantification of key TPs of UDMH and cost efficiency. 1-Trideuteromethyl-1H-1,2,4-triazole (MTA-d3) was used as the internal standard. Internal standard calibration allowed controlling matrix effects during quantification of 1-methyl-1H-1,2,4-triazole (MTA), N,N-dimethylformamide (DMF), and N-nitrosodimethylamine (NDMA) in soils with humus content < 1%. Using SPME at 60 °C for 15 min by 65 µm Carboxen/polydimethylsiloxane fiber, recoveries of MTA, DMF and NDMA for sandy and loamy soil samples were 91-117, 85-123 and 64-132%, respectively. For improving the method accuracy and widening the range of analytes, standard addition and its combination with internal standard calibration were tested and compared on real soil samples. The combined calibration approach provided greatest accuracies for NDMA, DMF, N-methylformamide, formamide, 1H-pyrazole, 3-methyl-1H-pyrazole and 1H-pyrazole. For determination of 1-formyl-2,2-dimethylhydrazine, 3,5-dimethylpyrazole, 2-ethyl-1H-imidazole, 1H-imidazole, 1H-1,2,4-triazole, pyrazines and pyridines, standard addition calibration is more suitable. However, the proposed approach and collected data allow using both approaches simultaneously. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Learning curves for solid oxide fuel cells

    International Nuclear Information System (INIS)

    Rivera-Tinoco, Rodrigo; Schoots, Koen; Zwaan, Bob van der

    2012-01-01

    Highlights: ► We present learning curves for fuel cells based on empirical data. ► We disentangle different cost reduction mechanisms for SOFCs. ► We distinguish between learning-by-doing, R and D, economies-of-scale and automation. - Abstract: In this article we present learning curves for solid oxide fuel cells (SOFCs). With data from fuel cell manufacturers we derive a detailed breakdown of their production costs. We develop a bottom-up model that allows for determining overall SOFC manufacturing costs with their respective cost components, among which material, energy, labor and capital charges. The results obtained from our model prove to deviate by at most 13% from total cost figures quoted in the literature. For the R and D stage of development and diffusion, we find local learning rates between 13% and 17% and we demonstrate that the corresponding cost reductions result essentially from learning-by-searching effects. When considering periods in time that focus on the pilot and early commercial production stages, we find regional learning rates of 27% and 1%, respectively, which we assume derive mainly from genuine learning phenomena. These figures turnout significantly higher, approximately 44% and 12% respectively, if also effects of economies-of-scale and automation are included. When combining all production stages we obtain lr = 35%, which represents a mix of cost reduction phenomena. This high learning rate value and the potential to scale up production suggest that continued efforts in the development of SOFC manufacturing processes, as well as deployment and use of SOFCs, may lead to substantial further cost reductions.

  14. Agglomeration and Deposition Behaviour of Solid Recovered Fuel

    DEFF Research Database (Denmark)

    Pedersen, Morten Nedergaard; Jensen, Peter Arendt; Nielsen, Mads

    2015-01-01

    Waste derived fuels such as Solid Recovered Fuel (SRF) are increasingly being used in the cement industry as a means to reduce cost [1]. SRF is produced by separating the combustible fraction from industrial or municipal solid waste (MSW). The recovered fraction has a higher content of combustibl...

  15. Advanced methods of solid oxide fuel cell modeling

    CERN Document Server

    Milewski, Jaroslaw; Santarelli, Massimo; Leone, Pierluigi

    2011-01-01

    Fuel cells are widely regarded as the future of the power and transportation industries. Intensive research in this area now requires new methods of fuel cell operation modeling and cell design. Typical mathematical models are based on the physical process description of fuel cells and require a detailed knowledge of the microscopic properties that govern both chemical and electrochemical reactions. ""Advanced Methods of Solid Oxide Fuel Cell Modeling"" proposes the alternative methodology of generalized artificial neural networks (ANN) solid oxide fuel cell (SOFC) modeling. ""Advanced Methods

  16. Performance Evaluation of Solid Oxide Fuel Cell by Computer ...

    African Journals Online (AJOL)

    The search for sustainable energy source that can compete with the existing one led to the discovery and acceptance of fuel cell technologies as a perfect replacement for fossil fuel. The ability of Solid Oxide Fuel Cells (SOFC) to capture the heat generation during the process of energy generation from electrochemical ...

  17. Stability of solid oxide fuel cell materials

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, T.R.; Bates, J.L.; Coffey, G.W.; Pederson, L.R. [Pacific Northwest National Lab., Richland, WA (United States)] [and others

    1996-08-01

    Chromite interconnection materials in an SOFC are exposed to both highly oxidizing conditions at the cathode and to highly reducing conditions at the anode. Because such conditions could lead to component failure, the authors have evaluated thermal, electrical, chemical, and structural stabilities of these materials as a function of temperature and oxygen partial pressure. The crystal lattice of the chromites was shown to expand for oxygen partial pressures smaller than 10{sup {minus}10} atm, which could lead to cracking and debonding in an SOFC. Highly substituted lanthanum chromite compositions were the most susceptible to lattice expansion; yttrium chromites showed better dimensional stability by more than a factor of two. New chromite compositions were developed that showed little tendency for lattice expansion under strongly reducing conditions, yet provided a good thermal expansion match to other fuel cell components. Use of these new chromite interconnect compositions should improve long-term SOFC performance, particularly for planar cell configurations. Thermodynamic properties of substituted lanthanum manganite cathode compositions have been determined through measurement of electromotive force as a function of temperature. Critical oxygen decomposition pressures for Sr and Ca-substituted lanthanum manganites were established using cells based on a zirconia electrolyte. Strontium oxide and calcium oxide activities in a lanthanum manganite matrix were determined using cells based on strontium fluoride and calcium fluoride electrolytes, respectively. The compositional range of single-phase behavior of these ABO{sub 3}-type perovskites was established as a function of A/B cation ratios and the extent of acceptor doping. Before this work, very little thermodynamic information was in existence for substituted manganite compositions. Such information is needed to predict the long-term stability of solid oxide fuel cell assemblies.

  18. Fuel/propellant mixing in an open-cycle gas core nuclear rocket engine

    International Nuclear Information System (INIS)

    Guo, X.; Wehrmeyer, J.A.

    1997-01-01

    A numerical investigation of the mixing of gaseous uranium and hydrogen inside an open-cycle gas core nuclear rocket engine (spherical geometry) is presented. The gaseous uranium fuel is injected near the centerline of the spherical engine cavity at a constant mass flow rate, and the hydrogen propellant is injected around the periphery of the engine at a five degree angle to the wall, at a constant mass flow rate. The main objective is to seek ways to minimize the mixing of uranium and hydrogen by choosing a suitable injector geometry for the mixing of light and heavy gas streams. Three different uranium inlet areas are presented, and also three different turbulent models (k-var-epsilon model, RNG k-var-epsilon model, and RSM model) are investigated. The commercial CFD code, FLUENT, is used to model the flow field. Uranium mole fraction, axial mass flux, and radial mass flux contours are obtained. copyright 1997 American Institute of Physics

  19. Addressing fuel recycling in solid oxide fuel cell systems fed by alternative fuels

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2017-01-01

    An innovative study on anode recirculation in solid oxide fuel cell systems with alternative fuels is carried out and investigated. Alternative fuels under study are ammonia, pure hydrogen, methanol, ethanol, DME and biogas from biomass gasification. It is shown that the amount of anode off......%. Furthermore, it is founded that for the case with methanol, ethanol and DME then at high utilization factors, low anode recirculation is recommended while at low utilization factors, high anode recirculation is recommended. If the plant is fed by biogas from biomass gasification then for each utilization...

  20. High performance Solid Rocket Motor (SRM) submerged nozzle/combustion cavity flowfield assessment

    Science.gov (United States)

    Freeman, J. A.; Chan, J. S.; Murph, J. E.; Xiques, K. E.

    1987-01-01

    Two and three dimensional internal flowfield solutions for critical points in the Space Shuttle solid rocket booster burn time were developed using the Lockheed Huntsville GIM/PAID Navier-Stokes solvers. These perfect gas, viscous solutions for the high performance motor characterize the flow in the aft segment and nozzle of the booster. Two dimensional axisymmetric solutions were developed at t = 20 and t = 85 sec motor burn times. The t = 85 sec solution indicates that the aft segment forward inhibitor stub produces vortices with are shed and convected downwards. A three dimensional 3.5 deg gimbaled nozzle flowfield solution was developed for the aft segment and nozzle at t = 9 sec motor burn time. This perfect gas, viscous analysis, provided a steady state solution for the core region and the flow through the nozzle, but indicated that unsteady flow exists in the region under the nozzle nose and near the flexible boot and nozzle/case joint. The flow in the nozzle/case joint region is characterized by low magnitude pressure waves which travel in the circumferential direction. From the two and three dimensional flowfield calculations presented it can be concluded that there is no evidence from these results that steady state gas dynamics is the primary mechanism resulting in the nozzle pocketing erosion experienced on SRM nozzles 8A or 17B. The steady state flowfield results indicate pocketing erosion is not directly initiated by a steady state gas dynamics phenomenon.

  1. Real-Time Inhibitor Recession Measurements in the Space Shuttle Reusable Solid Rocket Motors

    Science.gov (United States)

    McWhorter, Bruce B.; Ewing, Mark E.; McCool, Alex (Technical Monitor)

    2001-01-01

    Real-time char line recession measurements were made on propellant inhibitors of the Space Shuttle Reusable Solid Rocket Motor (RSRM). The RSRM FSM-8 static test motor propellant inhibitors (composed of a rubber insulation material) were successfully instrumented with eroding potentiometers and thermocouples. The data was used to establish inhibitor recession versus time relationships. Normally, pre-fire and post-fire insulation thickness measurements establish the thermal performance of an ablating insulation material. However, post-fire inhibitor decomposition and recession measurements are complicated by the fact that most of the inhibitor is back during motor operation. It is therefore a difficult task to evaluate the thermal protection offered by the inhibitor material. Real-time measurements would help this task. The instrumentation program for this static test motor marks the first time that real-time inhibitors. This report presents that data for the center and aft field joint forward facing inhibitors. The data was primarily used to measure char line recession of the forward face of the inhibitors which provides inhibitor thickness reduction versus time data. The data was also used to estimate the inhibitor height versus time relationship during motor operation.

  2. Numerical Evaluation of the Use of Aluminum Particles for Enhancing Solid Rocket Motor Combustion Stability

    Directory of Open Access Journals (Sweden)

    David Greatrix

    2015-02-01

    Full Text Available The ability to predict the expected internal behaviour of a given solid-propellant rocket motor under transient conditions is important. Research towards predicting and quantifying undesirable transient axial combustion instability symptoms typically necessitates a comprehensive numerical model for internal ballistic simulation under dynamic flow and combustion conditions. On the mitigation side, one in practice sees the use of inert or reactive particles for the suppression of pressure wave development in the motor chamber flow. With the focus of the present study placed on reactive particles, a numerical internal ballistic model incorporating relevant elements, such as a transient, frequency-dependent combustion response to axial pressure wave activity above the burning propellant surface, is applied to the investigation of using aluminum particles within the central internal flow (particles whose surfaces nominally regress with time, as a function of current particle size, as they move downstream as a means of suppressing instability-related symptoms in a cylindrical-grain motor. The results of this investigation reveal that the loading percentage and starting size of the aluminum particles have a significant influence on reducing the resulting transient pressure wave magnitude.

  3. Plume particle collection and sizing from static firing of solid rocket motors

    Science.gov (United States)

    Sambamurthi, Jay K.

    1995-01-01

    A unique dart system has been designed and built at the NASA Marshall Space Flight Center to collect aluminum oxide plume particles from the plumes of large scale solid rocket motors, such as the space shuttle RSRM. The capability of this system to collect clean samples from both the vertically fired MNASA (18.3% scaled version of the RSRM) motors and the horizontally fired RSRM motor has been demonstrated. The particle mass averaged diameters, d43, measured from the samples for the different motors, ranged from 8 to 11 mu m and were independent of the dart collection surface and the motor burn time. The measured results agreed well with those calculated using the industry standard Hermsen's correlation within the standard deviation of the correlation . For each of the samples analyzed from both MNASA and RSRM motors, the distribution of the cumulative mass fraction of the plume oxide particles as a function of the particle diameter was best described by a monomodal log-normal distribution with a standard deviation of 0.13 - 0.15. This distribution agreed well with the theoretical prediction by Salita using the OD3P code for the RSRM motor at the nozzle exit plane.

  4. Qualification Status of Non-Asbestos Internal Insulation in the Reusable Solid Rocket Motor Program

    Science.gov (United States)

    Clayton, Louie

    2011-01-01

    This paper provides a status of the qualification efforts associated with NASA's RSRMV non-asbestos internal insulation program. For many years, NASA has been actively engaged in removal of asbestos from the shuttle RSRM motors due to occupation health concerns where technicians are working with an EPA banned material. Careful laboratory and subscale testing has lead to the downselect of a organic fiber known as Polybenzimidazol to replace the asbestos fiber filler in the existing synthetic rubber copolymer Nitrile Butadiene - now named PBI/NBR. Manufacturing, processing, and layup of the new material has been a challenge due to the differences in the baseline shuttle RSRM internal insulator properties and PBI/NBR material properties. For this study, data gathering and reduction procedures for thermal and chemical property characterization for the new candidate material are discussed. Difficulties with test procedures, implementation of properties into the Charring Material Ablator (CMA) codes, and results correlation with static motor fire data are provided. After two successful five segment motor firings using the PBI/NBR insulator, performance results for the new material look good and the material should eventually be qualified for man rated use in large solid rocket motor applications.

  5. Reusable Solid Rocket Motor - V(RSRMV)Nozzle Forward Nose Ring Thermo-Structural Modeling

    Science.gov (United States)

    Clayton, J. Louie

    2012-01-01

    During the developmental static fire program for NASAs Reusable Solid Rocket Motor-V (RSRMV), an anomalous erosion condition appeared on the nozzle Carbon Cloth Phenolic nose ring that had not been observed in the space shuttle RSRM program. There were regions of augmented erosion located on the bottom of the forward nose ring (FNR) that measured nine tenths of an inch deeper than the surrounding material. Estimates of heating conditions for the RSRMV nozzle based on limited char and erosion data indicate that the total heat loading into the FNR, for the new five segment motor, is about 40-50% higher than the baseline shuttle RSRM nozzle FNR. Fault tree analysis of the augmented erosion condition has lead to a focus on a thermomechanical response of the material that is outside the existing experience base of shuttle CCP materials for this application. This paper provides a sensitivity study of the CCP material thermo-structural response subject to the design constraints and heating conditions unique to the RSRMV Forward Nose Ring application. Modeling techniques are based on 1-D thermal and porous media calculations where in-depth interlaminar loading conditions are calculated and compared to known capabilities at elevated temperatures. Parameters such as heat rate, in-depth pressures and temperature, degree of char, associated with initiation of the mechanical removal process are quantified and compared to a baseline thermo-chemical material removal mode. Conclusions regarding postulated material loss mechanisms are offered.

  6. Laser Shearography Inspection of TPS (Thermal Protection System) Cork on RSRM (Reusable Solid Rocket Motors)

    Science.gov (United States)

    Lingbloom, Mike; Plaia, Jim; Newman, John

    2006-01-01

    Laser Shearography is a viable inspection method for detection of de-bonds and voids within the external TPS (thermal protection system) on to the Space Shuttle RSRM (reusable solid rocket motors). Cork samples with thicknesses up to 1 inch were tested at the LTI (Laser Technology Incorporated) laboratory using vacuum-applied stress in a vacuum chamber. The testing proved that the technology could detect cork to steel un-bonds using vacuum stress techniques in the laboratory environment. The next logical step was to inspect the TPS on a RSRM. Although detailed post flight inspection has confirmed that ATK Thiokol's cork bonding technique provides a reliable cork to case bond, due to the Space Shuttle Columbia incident there is a great interest in verifying bond-lines on the external TPS. This interest provided and opportunity to inspect a RSRM motor with Laser Shearography. This paper will describe the laboratory testing and RSRM testing that has been performed to date. Descriptions of the test equipment setup and techniques for data collection and detailed results will be given. The data from the test show that Laser Shearography is an effective technology and readily adaptable to inspect a RSRM.

  7. Fracture tolerance analysis of the solid rocket booster servo-actuator for the space shuttle

    Energy Technology Data Exchange (ETDEWEB)

    Smith, S.H.; Ghadiali, N.D.; Zahoor, A.; Wilson, M.R.

    1982-01-01

    The results of an evaluation of the fracture tolerance of three components of the thrust vector control servo-actuator for the solid rocket booster of the space shuttle are described. These components were considered as being potentially fracture critical and therefore having the potential to fall short of a desired service life of 80 missions (that is, a service life factor of 4.0 on a basic service life of 20 missions). Detailed stress analysis of the rod end, cylinder, and feedback link components was accomplished by three-dimensional finite-element stress analysis methods. A dynamic structural model of the feedback system was used to determine the dynamic inertia loads and reactions to apply to the finite-element model of the feedback link. Twenty mission stress spectra consisting of lift-off, boost, re-entry, and water impact mission segments were developed for each component based on dynamic loadings. Most components were determined to have the potential of reaching a service life of 80 missions or service life factor of 4.0. 22 refs.

  8. Plume Particle Collection and Sizing from Static Firing of Solid Rocket Motors

    Science.gov (United States)

    Sambamurthi, Jay K.

    1995-01-01

    Thermal radiation from the plume of any solid rocket motor, containing aluminum as one of the propellant ingredients, is mainly from the microscopic, hot aluminum oxide particles in the plume. The plume radiation to the base components of the flight vehicle is primarily determined by the plume flowfield properties, the size distribution of the plume particles, and their optical properties. The optimum design of a vehicle base thermal protection system is dependent on the ability to accurately predict this intense thermal radiation using validated theoretical models. This article describes a successful effort to collect reasonably clean plume particle samples from the static firing of the flight simulation motor (FSM-4) on March 10, 1994 at the T-24 test bed at the Thiokol space operations facility as well as three 18.3% scaled MNASA motors tested at NASA/MSFC. Prior attempts to collect plume particles from the full-scale motor firings have been unsuccessful due to the extremely hostile thermal and acoustic environment in the vicinity of the motor nozzle.

  9. An analysis of the orbital distribution of solid rocket motor slag

    Science.gov (United States)

    Horstman, Matthew F.; Mulrooney, Mark

    2009-01-01

    The contribution by solid rocket motors (SRMs) to the orbital debris environment is potentially significant and insufficiently studied. Design and combustion processes can lead to the emission of enough by-products to warrant assessment of their contribution to orbital debris. These particles are formed during SRM tail-off, or burn termination, by the rapid solidification of molten Al2O3 slag accumulated during the burn. The propensity of SRMs to generate particles larger than 100μm raises concerns regarding the debris environment. Sizes as large as 1 cm have been witnessed in ground tests, and comparable sizes have been estimated via observations of sub-orbital tail-off events. Utilizing previous research we have developed more sophisticated size distributions and modeled the time evolution of resultant orbital populations using a historical database of SRM launches, propellant, and likely location and time of tail-off. This analysis indicates that SRM ejecta is a significant component of the debris environment.

  10. Analysis of pressure blips in aft-finocyl solid rocket motor

    Science.gov (United States)

    Di Giacinto, M.; Favini, B.; Cavallini, E.

    2016-07-01

    Ballistic anomalies have frequently occurred during the firing of several solid rocket motors (SRMs) (Inertial Upper Stage, Space Shuttle Redesigned SRM (RSRM) and Titan IV SRM Upgrade (SRMU)), producing even relevant and unexpected variations of the SRM pressure trace from its nominal profile. This paper has the purpose to provide a numerical analysis of the following possible causes of ballistic anomalies in SRMs: an inert object discharge, a slag ejection, and an unexpected increase in the propellant burning rate or in the combustion surface. The SRM configuration under investigation is an aft-finocyl SRM with a first-stage/small booster design. The numerical simulations are performed with a quasi-one-dimensional (Q1D) unsteady model of the SRM internal ballistics, properly tailored to model each possible cause of the ballistic anomalies. The results have shown that a classification based on the head-end pressure (HEP) signature, relating each other the HEP shape and the ballistic anomaly cause, can be made. For each cause of ballistic anomalies, a deepened discussion of the parameters driving the HEP signatures is provided, as well as qualitative and quantitative assessments of the resultant pressure signals.

  11. Development of solid oxide fuel cell technology

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Dae Kab; Kim, Sun Jae; Jung, Choong Hwan; Kim, Kyung Hoh; Park, Ji Yun; Oh, Suk Jin [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-01-01

    Solid Oxide Fuel Cell (SOFC) technologies that use zirconium oxide as the electrolyte material were studied in this present report. SOFC exhibits a very high power generation efficiency of over 50 %, and does not discharge pollution materials such as dusts, sulfur dioxide, and nitrogen oxide. Zirconia, Ni/YSZ (yttria stabilized zirconia), and La-Sr-Mn-Oxide materials were developed for the electrolyte material, for the anode, and for the cathode, respectively. After making thin zirconia plate using tape casting process, anode and cathode powders were screen printed on the zirconia plate for fabricating unit cells. A test system composed of a vertical tube furnace, digital multimeter, DC current supplier, and measuring circuit was constructed for testing the unit cell performance. This system was controlled by a home-made computer program. Founded on this unit cell technology and system, a multi-stack SOFC system was studied. This system was composed of 10 unit cells each of them had an electrode area of 40 x 40 mm. Based on this system design, large and thin zirconia plates of 70 x 70 mm in area was fabricated for the electrolyte. Different from in the unit cell system, interconnectors are needed in the multi-stack system for connecting unit cells electrically. For this interconnectors, Inconel 750 alloy was selected, sliced into wafers, machined, surface finished, and then Pt-plated. 55 figs, 8 tabs, 51 refs. (Author).

  12. Sealing materials for solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, P.H.

    1999-02-01

    A major obstacle in the achievement of high electrical efficiency for planar solid oxide fuel cell stacks (SOFC) is the need for long term stable seals at the operational temperature between 850 and 1000 deg. C. In the present work the formation and properties of sealing materials for SOFC stacks that fulfil the necessary requirements were investigated. The work comprises analysis of sealing material properties independently, in simple systems as well as tests in real SOFC stacks. The analysed sealing materials were based on pure glasses or glass-ceramic composites having B{sub 2}O{sub 3}, P{sub 2}O{sub 5} or siO{sub 2} as glass formers, and the following four glass systems were investigated: MgO/caO/Cr{sub 2}O{sub 3}-Al{sub 2}O{sub 3}B{sub 2}O{sub 3}-P{sub 2}O{sub 5}, MgO-Al{sub 2}O{sub 3}-P{sub 2}O{sub 5}, MgO-Al{sub 2}O{sub 3}-P{sub 2}O{sub 5}-SiO{sub 2} and BaO/Na{sub 2}O-Al{sub 2}O{sub 3}-SiO{sub 2}. (au) 32 tabs., 106 ills., 107 refs.

  13. Development of solid oxide fuel cell technology

    International Nuclear Information System (INIS)

    Kang, Dae Kab; Kim, Sun Jae; Jung, Choong Hwan; Kim, Kyung Hoh; Park, Ji Yun; Oh, Suk Jin

    1995-01-01

    Solid Oxide Fuel Cell (SOFC) technologies that use zirconium oxide as the electrolyte material were studied in this present report. SOFC exhibits a very high power generation efficiency of over 50 %, and does not discharge pollution materials such as dusts, sulfur dioxide, and nitrogen oxide. Zirconia, Ni/YSZ (yttria stabilized zirconia), and La-Sr-Mn-Oxide materials were developed for the electrolyte material, for the anode, and for the cathode, respectively. After making thin zirconia plate using tape casting process, anode and cathode powders were screen printed on the zirconia plate for fabricating unit cells. A test system composed of a vertical tube furnace, digital multimeter, DC current supplier, and measuring circuit was constructed for testing the unit cell performance. This system was controlled by a home-made computer program. Founded on this unit cell technology and system, a multi-stack SOFC system was studied. This system was composed of 10 unit cells each of them had an electrode area of 40 x 40 mm. Based on this system design, large and thin zirconia plates of 70 x 70 mm in area was fabricated for the electrolyte. Different from in the unit cell system, interconnectors are needed in the multi-stack system for connecting unit cells electrically. For this interconnectors, Inconel 750 alloy was selected, sliced into wafers, machined, surface finished, and then Pt-plated. 55 figs, 8 tabs, 51 refs. (Author)

  14. Combustion of large solid fuels in cement rotary kilns

    DEFF Research Database (Denmark)

    Nielsen, Anders Rooma

    (MBM), waste wood, sewage sludge, paper and plastics. The alternative fuel share of the total energy varies significantly from region to region, but the general trend is towards increased alternative fuel utilization. Solid alternative fuels typically have physical and chemical properties that differ...... from traditional solid fossil fuels. This creates a need for new combustion equipment or modification of existing kiln systems, because alternative fuels may influence process stability and product quality. Process stability is mainly influenced by exposing the raw material bed in the rotary kiln...... oxidation is a slow process which may greatly reduce the amounts of solid fuels to be utilized in the material inlet end of rotary kilns due to the limited residence time. Several parameters control the rate of char oxidation: a) bulk oxygen concentration, b) mass transfer rate of oxygen to char particles...

  15. A multilayered thick cylindrical shell under internal pressure and thermal loads applicable to solid propellant rocket motors

    Energy Technology Data Exchange (ETDEWEB)

    Renganathan, K.; Nageswara Rao, B.; Jana, M.K. [Vikram Sarabhai Space Centre, Trivandrum (India). Structural Engineering Group

    2000-09-01

    A solid propellant rocket motor can be considered to be made of various circumferential layers of different properties. A simple procedure is described here to obtain an analytical solution for the general case of multilayered thick cyclindrical shell for internal pressure and thermal loads. This analytical procedure is useful in the preliminary design analysis of solid propellant rocket motors. Since solid propellant material is of viscoelastic behaviour an approximate viscoelastic solution methodology for the multilayered shell is described for estimation of time dependent solutions of propellant grain in a rocket motor. The analytical solution for a two layer reinforced thick cylindrical shell available in the literature is shown to be a special case of the present analytical solution. The results from the present analytical solution for multilayers is found to be in good agreement with FEA results. (orig.) [German] Der grundlegende Aufbau von Feststoffraketenmotoren kann auf einen Zylinder aus mehreren Schichten mit unterschiedlichen Eigenschaften zurueckgefuehrt werden. Eine einfache Berechnungsprozedur fuer die analytische Loesung des allgemeinen Falles eines mehrschichtigen Zylinders unter innerem Druck und thermischer Belastung wird hier vorgestellt. Diese analytische Methodik ist fuer den Auslegungsprozess von Feststoffraketenmotoren von grundlegender Bedeutung. Das viskoelastische Fliessverhalten des festen Brennstoffes, das den zeitlichen Ablauf des Verbrennungsprozesses wesentlich bestimmt, wird durch ein Naeherungsverfahren gut erfasst. Ein in der Literatur enthaltenes spezielles Ergebnis fuer einen zweischaligen verstaerkten Zylinder ergibt sich als Sonderfall der hier vorgestellten Methodik. Die analytisch erhaltenen Loesungen fuer mehrschichtige Aufbauten sind in guter Uebereinstimmung mit mittels der FEM ermittelten Ergebnisse. (orig.)

  16. A review of the performance and structural considerations of paraffin wax hybrid rocket fuels with additives

    Science.gov (United States)

    Veale, Kirsty; Adali, Sarp; Pitot, Jean; Brooks, Michael

    2017-12-01

    Paraffin wax as a hybrid rocket fuel has not been comprehensively characterised, especially regarding the structural feasibility of the material in launch applications. Preliminary structural testing has shown paraffin wax to be a brittle, low strength material, and at risk of failure under launch loading conditions. Structural enhancing additives have been identified, but their effect on motor performance has not always been considered, nor has any standard method of testing been identified between research institutes. A review of existing regression rate measurement techniques on paraffin wax based fuels and the results obtained with various additives are collated and discussed in this paper. The review includes 2D slab motors that enable visualisation of liquefying fuel droplet entrainment and the effect of an increased viscosity on the droplet entrainment mechanism, which can occur with the addition of structural enhancing polymers. An increased viscosity has been shown to reduce the regression rate of liquefying fuels. Viscosity increasing additives that have been tested include EVA and LDPE. Both these additives increase the structural properties of paraffin wax, where the elongation and UTS are improved. Other additives, such as metal hydrides, aluminium and boron generally offer improvements on the regression rate. However, very little consideration has been given to the structural effects these additives have on the wax grain. A 40% aluminised grain, for example, offers a slight increase in the UTS but reduces the elongation of paraffin wax. Geometrically accurate lab-scale motors have also been used to determine the regression rate properties of various additives in paraffin wax. A concise review of all available regression rate testing techniques and results on paraffin wax based hybrid propellants, as well as existing structural testing data, is presented in this paper.

  17. Sounding rockets explore the ionosphere

    International Nuclear Information System (INIS)

    Mendillo, M.

    1990-01-01

    It is suggested that small, expendable, solid-fuel rockets used to explore ionospheric plasma can offer insight into all the processes and complexities common to space plasma. NASA's sounding rocket program for ionospheric research focuses on the flight of instruments to measure parameters governing the natural state of the ionosphere. Parameters include input functions, such as photons, particles, and composition of the neutral atmosphere; resultant structures, such as electron and ion densities, temperatures and drifts; and emerging signals such as photons and electric and magnetic fields. Systematic study of the aurora is also conducted by these rockets, allowing sampling at relatively high spatial and temporal rates as well as investigation of parameters, such as energetic particle fluxes, not accessible to ground based systems. Recent active experiments in the ionosphere are discussed, and future sounding rocket missions are cited

  18. A study of performance and cost improvement potential of the 120 inch (3.05 m) diameter solid rocket motor. Volume 1: Summary report

    Science.gov (United States)

    Backlund, S. J.; Rossen, J. N.

    1971-01-01

    A parametric study of ballistic modifications to the 120 inch diameter solid propellant rocket engine which forms part of the Air Force Titan 3 system is presented. 576 separate designs were defined and 24 were selected for detailed analysis. Detailed design descriptions, ballistic performance, and mass property data were prepared for each design. It was determined that a relatively simple change in design parameters could provide a wide range of solid propellant rocket engine ballistic characteristics for future launch vehicle applications.

  19. Effect of buoyancy on fuel containment in an open-cycle gas-core nuclear rocket engine.

    Science.gov (United States)

    Putre, H. A.

    1971-01-01

    Analysis aimed at determining the scaling laws for the buoyancy effect on fuel containment in an open-cycle gas-core nuclear rocket engine, so conducted that experimental conditions can be related to engine conditions. The fuel volume fraction in a short coaxial flow cavity is calculated with a programmed numerical solution of the steady Navier-Stokes equations for isothermal, variable density fluid mixing. A dimensionless parameter B, called the Buoyancy number, was found to correlate the fuel volume fraction for large accelerations and various density ratios. This parameter has the value B = 0 for zero acceleration, and B = 350 for typical engine conditions.

  20. An Internal Thermal Environment Model of an Aluminized Solid Rocket Motor with Experimental Validation

    Science.gov (United States)

    Martin, Heath T.

    2015-01-01

    Due to the severity of the internal solid rocket motor (SRM) environment, very few direct measurements of that environment exist; therefore, the appearance of such data provides a unique opportunity to assess current thermal/fluid modeling capabilities. As part of a previous study of SRM internal insulation performance, the internal thermal environment of a laboratory-scale SRM featuring aluminized propellant was characterized with two types of custom heat-flux calorimeters: one that measured the total heat flux to a graphite slab within the SRM chamber and another that measured the thermal radiation flux. Therefore, in the current study, a thermal/fluid model of this lab-scale SRM was constructed using ANSYS Fluent to predict not only the flow field structure within the SRM and the convective heat transfer to the interior walls, but also the resulting dispersion of alumina droplets and the radiative heat transfer to the interior walls. The dispersion of alumina droplets within the SRM chamber was determined by employing the Lagrangian discrete phase model that was fully coupled to the Eulerian gas-phase flow. The P1-approximation was engaged to model the radiative heat transfer through the SRM chamber where the radiative contributions of the gas phase were ignored and the aggregate radiative properties of the alumina dispersion were computed from the radiative properties of its individual constituent droplets, which were sourced from literature. The convective and radiative heat fluxes computed from the thermal/fluid model were then compared with those measured in the lab-scale SRM test firings and the modeling approach evaluated.

  1. Modeling the Gas Dynamics Environment in a Subscale Solid Rocket Test Motor

    Science.gov (United States)

    Eaton, Andrew M.; Ewing, Mark E.; Bailey, Kirk M.; McCool, Alex (Technical Monitor)

    2001-01-01

    Subscale test motors are often used for the evaluation of solid rocket motor component materials such as internal insulation. These motors are useful for characterizing insulation performance behavior, screening insulation material candidates and obtaining material thermal and ablative property design data. One of the primary challenges associated with using subscale motors however, is the uncertainty involved when extrapolating the results to full-scale motor conditions. These uncertainties are related to differences in such phenomena as turbulent flow behavior and boundary layer development, propellant particle interactions with the wall, insulation off-gas mixing and thermochemical reactions with the bulk flow, radiation levels, material response to the local environment, and other anomalous flow conditions. In addition to the need for better understanding of physical mechanisms, there is also a need to better understand how to best simulate these phenomena using numerical modeling approaches such as computational fluid dynamics (CFD). To better understand and model interactions between major phenomena in a subscale test motor, a numerical study of the internal flow environment of a representative motor was performed. Simulation of the environment included not only gas dynamics, but two-phase flow modeling of entrained alumina particles like those found in an aluminized propellant, and offgassing from wall surfaces similar to an ablating insulation material. This work represents a starting point for establishing the internal environment of a subscale test motor using comprehensive modeling techniques, and lays the groundwork for improving the understanding of the applicability of subscale test data to full-scale motors. It was found that grid resolution, and inclusion of phenomena in addition to gas dynamics, such as two-phase and multi-component gas composition are all important factors that can effect the overall flow field predictions.

  2. Obtaining fuel briquets from the solid municipal waste

    International Nuclear Information System (INIS)

    Armenski, Slave; Kachurkov, Gjorgji; Vasilevski, Goce

    1998-01-01

    Recycling systems for solid waste materials are designed to reduce the amount of solid waste materials going to land fields. Through the Trash Separation Systems, clean municipal waste are reused in production of fuel pellets. Other waste streams such as coal fines, sawdust, wood chips, coke breeze and agricultural waste can be blended with these pellets along with a high thermal value binder and/or used motor oil to form a quality clean burning alternative fuel. (Author)

  3. Solid-fuel cook stoves: Fuel efficiency and emissions testing--Austin

    Science.gov (United States)

    The World Health Organization estimates that approximately 1.6 million people prematurely die each year due to exposure to air pollutants from burning solid fuels for residential cooking and heating (WHO, 2010). Residential solid-fuel use accounts for approximately 25 percent of ...

  4. The development of an erosive burning model for solid rocket motors using direct numerical simulation

    Science.gov (United States)

    McDonald, Brian A.

    A method for developing an erosive burning model for use in solid propellant design-and-analysis interior ballistics codes is described and evaluated. Using Direct Numerical Simulation, the primary mechanisms controlling erosive burning (turbulent heat transfer, and finite rate reactions) have been studied independently through the development of models using finite rate chemistry, and infinite rate chemistry. Both approaches are calibrated to strand burn rate data by modeling the propellant burning in an environment with no cross-flow, and adjusting thermophysical properties until the predicted regression rate matches test data. Subsequent runs are conducted where the cross-flow is increased from M = 0.0 up to M = 0.8. The resulting relationship of burn rate increase versus Mach Number is used in an interior ballistics analysis to compute the chamber pressure of an existing solid rocket motor. The resulting predictions are compared to static test data. Both the infinite rate model and the finite rate model show good agreement when compared to test data. The propellant considered is an AP/HTPB with an average AP particle size of 37 microns. The finite rate model shows that as the cross-flow increases, near wall vorticity increases due to the lifting of the boundary caused by the side injection of gases from the burning propellant surface. The point of maximum vorticity corresponds to the outer edge of the APd-binder flame. As the cross-flow increases, the APd-binder flame thickness becomes thinner; however, the point of highest reaction rate moves only slightly closer to the propellant surface. As such, the net increase of heat transfer to the propellant surface due to finite rate chemistry affects is small. This leads to the conclusion that augmentation of thermal transport properties and the resulting heat transfer increase due to turbulence dominates over combustion chemistry in the erosive burning problem. This conclusion is advantageous in the development of

  5. Apparatus and method for solid fuel chemical looping combustion

    Science.gov (United States)

    Siriwardane, Ranjani V; Weber, Justin M

    2015-04-14

    The disclosure provides an apparatus and method utilizing fuel reactor comprised of a fuel section, an oxygen carrier section, and a porous divider separating the fuel section and the oxygen carrier section. The porous divider allows fluid communication between the fuel section and the oxygen carrier section while preventing the migration of solids of a particular size. Maintaining particle segregation between the oxygen carrier section and the fuel section during solid fuel gasification and combustion processes allows gases generated in either section to participate in necessary reactions while greatly mitigating issues associated with mixture of the oxygen carrier with char or ash products. The apparatus and method may be utilized with an oxygen uncoupling oxygen carrier such as CuO, Mn.sub.3O.sub.4, or Co.sub.3O.sub.4, or utilized with a CO/H.sub.2 reducing oxygen carrier such as Fe.sub.2O.sub.3.

  6. Solid state nuclear magnetic resonance of fossil fuels

    International Nuclear Information System (INIS)

    Axelson, D.E.

    1985-01-01

    This book contains the following chapters: Principles of solid state NMR; Relaxation processes: Introduction to pulse sequences; Quantitative analysis; Removal of artifacts from CPMAS FT experiments; Line broadening mechanisms; Resolution enhancement of solid state NMR spectra; and /sup 13/C CPMAS NMR of fossil fuels--general applications

  7. THE DETERMINATION OF VOLATILE COMPOSITION OF SOLID FUELS BY CHROMATOGRAPHY

    OpenAIRE

    BICA Marin; SOFRONIE Sorin; CERNAIANU Corina Dana

    2014-01-01

    The volatile materials released during the heating of solid fuels ignite at relatively low temperatures releasing heat function of their quantity and quality. This heat raises the temperature of the solid residue creating the conditions for his ignition and burning. In the case of burning of the pulverized coal the phenomenon of production, ignition and burning of volatile materials are studied in different articles.

  8. Design and Fabrication of a 200N Thrust Rocket Motor Based on NH4ClO4+Al+HTPB as Solid Propellant

    Science.gov (United States)

    Wahid, Mastura Ab; Ali, Wan Khairuddin Wan

    2010-06-01

    The development of rocket motor using potassium nitrate, carbon and sulphur mixture has successfully been developed by researchers and students from UTM and recently a new combination for solid propellant is being created. The new solid propellant will combine a composition of Ammonium perchlorate, NH4ClO4 with aluminium, Al and Hydroxyl Terminated Polybutadiene, HTPB as the binder. It is the aim of this research to design and fabricate a new rocket motor that will produce a thrust of 200N by using this new solid propellant. A static test is done to obtain the thrust produced by the rocket motor and analyses by observation and also calculation will be done. The experiment for the rocket motor is successful but the thrust did not achieve its required thrust.

  9. Removing hydrochloric acid exhaust products from high performance solid rocket propellant using aluminum-lithium alloy.

    Science.gov (United States)

    Terry, Brandon C; Sippel, Travis R; Pfeil, Mark A; Gunduz, I Emre; Son, Steven F

    2016-11-05

    Hydrochloric acid (HCl) pollution from perchlorate based propellants is well known for both launch site contamination, as well as the possible ozone layer depletion effects. Past efforts in developing environmentally cleaner solid propellants by scavenging the chlorine ion have focused on replacing a portion of the chorine-containing oxidant (i.e., ammonium perchlorate) with an alkali metal nitrate. The alkali metal (e.g., Li or Na) in the nitrate reacts with the chlorine ion to form an alkali metal chloride (i.e., a salt instead of HCl). While this technique can potentially reduce HCl formation, it also results in reduced ideal specific impulse (ISP). Here, we show using thermochemical calculations that using aluminum-lithium (Al-Li) alloy can reduce HCl formation by more than 95% (with lithium contents ≥15 mass%) and increase the ideal ISP by ∼7s compared to neat aluminum (using 80/20 mass% Al-Li alloy). Two solid propellants were formulated using 80/20 Al-Li alloy or neat aluminum as fuel additives. The halide scavenging effect of Al-Li propellants was verified using wet bomb combustion experiments (75.5±4.8% reduction in pH, ∝ [HCl], when compared to neat aluminum). Additionally, no measurable HCl evolution was detected using differential scanning calorimetry coupled with thermogravimetric analysis, mass spectrometry, and Fourier transform infrared absorption. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Experimental determination of convective heat transfer coefficients in the separated flow region of the Space Shuttle Solid Rocket Motor

    Science.gov (United States)

    Whitesides, R. Harold; Majumdar, Alok K.; Jenkins, Susan L.; Bacchus, David L.

    1990-01-01

    A series of cold flow heat transfer tests was conducted with a 7.5-percent scale model of the Space Shuttle Rocket Motor (SRM) to measure the heat transfer coefficients in the separated flow region around the nose of the submerged nozzle. Modifications were made to an existing 7.5 percent scale model of the internal geometry of the aft end of the SRM, including the gimballed nozzle in order to accomplish the measurements. The model nozzle nose was fitted with a stainless steel shell with numerous thermocouples welded to the backside of the thin wall. A transient 'thin skin' experimental technique was used to measure the local heat transfer coefficients. The effects of Reynolds number, nozzle gimbal angle, and model location were correlated with a Stanton number versus Reynolds number correlation which may be used to determine the convective heating rates for the full scale Space Shuttle Solid Rocket Motor nozzle.

  11. Sulfur Release from Cement Raw Materials during Solid Fuel Combustion

    DEFF Research Database (Denmark)

    Nielsen, Anders Rooma; Larsen, Morten B.; Glarborg, Peter

    2011-01-01

    During combustion of solid fuels in the material inlet end of cement rotary kilns, local reducing conditions can occur and cause decomposition of sulfates from cement raw materials. Decomposition of sulfates is problematic because it increases the gas-phase SO2 concentration, which may cause...... deposit formation in the kiln system. SO2 release from cement raw materials during combustion of solid fuels has been studied experimentally in a high temperature rotary drum. The fuels were tire rubber, pine wood, petcoke, sewage sludge, and polypropylene. The SO2 release from the raw materials...

  12. On use of hybrid rocket propulsion for suborbital vehicles

    Science.gov (United States)

    Okninski, Adam

    2018-04-01

    While the majority of operating suborbital rockets use solid rocket propulsion, recent advancements in the field of hybrid rocket motors lead to renewed interest in their use in sounding rockets. This paper presents results of optimisation of sounding rockets using hybrid propulsion. An overview of vehicles under development during the last decade, as well as heritage systems is provided. Different propellant combinations are discussed and their performance assessment is given. While Liquid Oxygen, Nitrous Oxide and Nitric Acid have been widely tested with various solid fuels in flight, Hydrogen Peroxide remains an oxidiser with very limited sounding rocket applications. The benefits of hybrid propulsion for sounding rockets are given. In case of hybrid rocket motors the thrust curve can be optimised for each flight, using a flow regulator, depending on the payload and mission. Results of studies concerning the optimal burn duration and nozzle selection are given. Specific considerations are provided for the Polish ILR-33 "Amber" sounding rocket. Low regression rates, which up to date were viewed as a drawback of hybrid propulsion may be used to the benefit of maximising rocket performance if small solid rocket boosters are used during the initial flight period. While increased interest in hybrid propulsion is present, no up-to-date reference concerning use of hybrid rocket propulsion for sounding rockets is available. The ultimate goal of the paper is to provide insight into the sensitivity of different design parameters on performance of hybrid sounding rockets and delve into the potential and challenges of using hybrid rocket technology for expendable suborbital applications.

  13. Direct Coal Oxidation in Modified Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Deleebeeck, Lisa; Gil, Vanesa; Ippolito, Davide

    2015-01-01

    Hybrid direct carbon fuel cells employ a classical solid oxide fuel cell together with carbon dispersed in a carbonate melt on the anode side. In a European project, the utilization of various coals has been investigated with and without addition of an oxidation catalyst to the carbon-carbonate s......Hybrid direct carbon fuel cells employ a classical solid oxide fuel cell together with carbon dispersed in a carbonate melt on the anode side. In a European project, the utilization of various coals has been investigated with and without addition of an oxidation catalyst to the carbon......-carbonate slurry or anode layer. The nature of the coal affects both open circuit voltage and power output. Highest OCV and power densities were observed for bituminous coal and by adding manganese oxide or praseodymium-doped ceria to the carbon/carbonate mixture. Comparing the carbon black fueled performance...... bituminous coal (73 mW/cm2). © 2015 ECS - The Electrochemical Society...

  14. Direct Coal Oxidation in Modified Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Deleebeeck, Lisa; Gil, Vanesa; Ippolito, Davide

    2017-01-01

    Hybrid direct carbon fuel cells employ a classical solid oxide fuel cell together with carbon dispersed in a carbonate melt on the anode side. In a European project, the utilization of various coals has been investigated with and without addition of an oxidation catalyst to the carbon-carbonate s......Hybrid direct carbon fuel cells employ a classical solid oxide fuel cell together with carbon dispersed in a carbonate melt on the anode side. In a European project, the utilization of various coals has been investigated with and without addition of an oxidation catalyst to the carbon......-carbonate slurry or anode layer. The nature of the coal affects both open circuit voltage and power output. Highest OCV and power densities were observed for bituminous coal and by adding manganese oxide or praseodymium-doped ceria to the carbon/carbonate mixture. Comparing the carbon black fueled performance...... bituminous coal (73 mW/cm2)....

  15. Quantity Distance for the Kennedy Space Center Vehicle Assembly Building for Solid Propellant Fueled Launchers

    Science.gov (United States)

    Stover, Steven; Diebler, Corey; Frazier, Wayne

    2006-01-01

    The NASA KSC VAB was built to process Apollo launchers in the 1960's, and later adapted to process Space Shuttles. The VAB has served as a place to assemble solid rocket motors (5RM) and mate them to the vehicle's external fuel tank and Orbiter before rollout to the launch pad. As Space Shuttle is phased out, and new launchers are developed, the VAB may again be adapted to process these new launchers. Current launch vehicle designs call for continued and perhaps increased use of SRM segments; hence, the safe separation distances are in the process of being re-calculated. Cognizant NASA personnel and the solid rocket contractor have revisited the above VAB QD considerations and suggest that it may be revised to allow a greater number of motor segments within the VAB. This revision assumes that an inadvertent ignition of one SRM stack in its High Bay need not cause immediate and complete involvement of boosters that are part of a vehicle in adjacent High Bay. To support this assumption, NASA and contractor personnel proposed a strawman test approach for obtaining subscale data that may be used to develop phenomenological insight and to develop confidence in an analysis model for later use on full-scale situations. A team of subject matter experts in safety and siting of propellants and explosives were assembled to review the subscale test approach and provide options to NASA. Upon deliberations regarding the various options, the team arrived at some preliminary recommendations for NASA.

  16. Hybrid rocket engine, theoretical model and experiment

    Science.gov (United States)

    Chelaru, Teodor-Viorel; Mingireanu, Florin

    2011-06-01

    The purpose of this paper is to build a theoretical model for the hybrid rocket engine/motor and to validate it using experimental results. The work approaches the main problems of the hybrid motor: the scalability, the stability/controllability of the operating parameters and the increasing of the solid fuel regression rate. At first, we focus on theoretical models for hybrid rocket motor and compare the results with already available experimental data from various research groups. A primary computation model is presented together with results from a numerical algorithm based on a computational model. We present theoretical predictions for several commercial hybrid rocket motors, having different scales and compare them with experimental measurements of those hybrid rocket motors. Next the paper focuses on tribrid rocket motor concept, which by supplementary liquid fuel injection can improve the thrust controllability. A complementary computation model is also presented to estimate regression rate increase of solid fuel doped with oxidizer. Finally, the stability of the hybrid rocket motor is investigated using Liapunov theory. Stability coefficients obtained are dependent on burning parameters while the stability and command matrixes are identified. The paper presents thoroughly the input data of the model, which ensures the reproducibility of the numerical results by independent researchers.

  17. Metallized solid rocket propellants based on AN/AP and PSAN/AP for access to space

    Science.gov (United States)

    Levi, S.; Signoriello, D.; Gabardi, A.; Molinari, M.; Galfetti, L.; Deluca, L. T.; Cianfanelli, S.; Klyakin, G. F.

    2009-09-01

    Solid rocket propellants based on dual mixes of inorganic crystalline oxidizers (ammonium nitrate (AN) and ammonium perchlorate (AP)) with binder and a mixture of micrometric-nanometric aluminum were investigated. Ammonium nitrate is a low-cost oxidizer, producing environment friendly combustion products but with lower specific impulse compared to AP. The better performance obtained with AP and the low quantity of toxic emissions obtained by using AN have suggested an interesting compromise based on a dual mixture of the two oxidizers. To improve the thermal response of raw AN, different types of phase stabilized AN (PSAN) and AN/AP co-crystals were investigated.

  18. Removing hydrochloric acid exhaust products from high performance solid rocket propellant using aluminum-lithium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Terry, Brandon C., E-mail: terry13@purdue.edu [School of Aeronautics and Astronautics, Purdue University, Zucrow Laboratories, 500 Allison Rd, West Lafayette, IN 47907 (United States); Sippel, Travis R. [Department of Mechanical Engineering, Iowa State University, 2025 Black Engineering, Ames, IA 50011 (United States); Pfeil, Mark A. [School of Aeronautics and Astronautics, Purdue University, Zucrow Laboratories, 500 Allison Rd, West Lafayette, IN 47907 (United States); Gunduz, I.Emre; Son, Steven F. [School of Mechanical Engineering, Purdue University, Zucrow Laboratories, 500 Allison Rd, West Lafayette, IN 47907 (United States)

    2016-11-05

    Highlights: • Al-Li alloy propellant has increased ideal specific impulse over neat aluminum. • Al-Li alloy propellant has a near complete reduction in HCl acid formation. • Reduction in HCl was verified with wet bomb experiments and DSC/TGA-MS/FTIR. - Abstract: Hydrochloric acid (HCl) pollution from perchlorate based propellants is well known for both launch site contamination, as well as the possible ozone layer depletion effects. Past efforts in developing environmentally cleaner solid propellants by scavenging the chlorine ion have focused on replacing a portion of the chorine-containing oxidant (i.e., ammonium perchlorate) with an alkali metal nitrate. The alkali metal (e.g., Li or Na) in the nitrate reacts with the chlorine ion to form an alkali metal chloride (i.e., a salt instead of HCl). While this technique can potentially reduce HCl formation, it also results in reduced ideal specific impulse (I{sub SP}). Here, we show using thermochemical calculations that using aluminum-lithium (Al-Li) alloy can reduce HCl formation by more than 95% (with lithium contents ≥15 mass%) and increase the ideal I{sub SP} by ∼7 s compared to neat aluminum (using 80/20 mass% Al-Li alloy). Two solid propellants were formulated using 80/20 Al-Li alloy or neat aluminum as fuel additives. The halide scavenging effect of Al-Li propellants was verified using wet bomb combustion experiments (75.5 ± 4.8% reduction in pH, ∝ [HCl], when compared to neat aluminum). Additionally, no measurable HCl evolution was detected using differential scanning calorimetry coupled with thermogravimetric analysis, mass spectrometry, and Fourier transform infrared absorption.

  19. Removing hydrochloric acid exhaust products from high performance solid rocket propellant using aluminum-lithium alloy

    International Nuclear Information System (INIS)

    Terry, Brandon C.; Sippel, Travis R.; Pfeil, Mark A.; Gunduz, I.Emre; Son, Steven F.

    2016-01-01

    Highlights: • Al-Li alloy propellant has increased ideal specific impulse over neat aluminum. • Al-Li alloy propellant has a near complete reduction in HCl acid formation. • Reduction in HCl was verified with wet bomb experiments and DSC/TGA-MS/FTIR. - Abstract: Hydrochloric acid (HCl) pollution from perchlorate based propellants is well known for both launch site contamination, as well as the possible ozone layer depletion effects. Past efforts in developing environmentally cleaner solid propellants by scavenging the chlorine ion have focused on replacing a portion of the chorine-containing oxidant (i.e., ammonium perchlorate) with an alkali metal nitrate. The alkali metal (e.g., Li or Na) in the nitrate reacts with the chlorine ion to form an alkali metal chloride (i.e., a salt instead of HCl). While this technique can potentially reduce HCl formation, it also results in reduced ideal specific impulse (I_S_P). Here, we show using thermochemical calculations that using aluminum-lithium (Al-Li) alloy can reduce HCl formation by more than 95% (with lithium contents ≥15 mass%) and increase the ideal I_S_P by ∼7 s compared to neat aluminum (using 80/20 mass% Al-Li alloy). Two solid propellants were formulated using 80/20 Al-Li alloy or neat aluminum as fuel additives. The halide scavenging effect of Al-Li propellants was verified using wet bomb combustion experiments (75.5 ± 4.8% reduction in pH, ∝ [HCl], when compared to neat aluminum). Additionally, no measurable HCl evolution was detected using differential scanning calorimetry coupled with thermogravimetric analysis, mass spectrometry, and Fourier transform infrared absorption.

  20. Assessment of bio-fuel options for solid oxide fuel cell applications

    Science.gov (United States)

    Lin, Jiefeng

    Rising concerns of inadequate petroleum supply, volatile crude oil price, and adverse environmental impacts from using fossil fuels have spurred the United States to promote bio-fuel domestic production and develop advanced energy systems such as fuel cells. The present dissertation analyzed the bio-fuel applications in a solid oxide fuel cell-based auxiliary power unit from environmental, economic, and technological perspectives. Life cycle assessment integrated with thermodynamics was applied to evaluate the environmental impacts (e.g., greenhouse gas emission, fossil energy consumption) of producing bio-fuels from waste biomass. Landfill gas from municipal solid wastes and biodiesel from waste cooking oil are both suggested as the promising bio-fuel options. A nonlinear optimization model was developed with a multi-objective optimization technique to analyze the economic aspect of biodiesel-ethanol-diesel ternary blends used in transportation sectors and capture the dynamic variables affecting bio-fuel productions and applications (e.g., market disturbances, bio-fuel tax credit, policy changes, fuel specification, and technological innovation). A single-tube catalytic reformer with rhodium/ceria-zirconia catalyst was used for autothermal reformation of various heavy hydrocarbon fuels (e.g., diesel, biodiesel, biodiesel-diesel, and biodiesel-ethanol-diesel) to produce a hydrogen-rich stream reformates suitable for use in solid oxide fuel cell systems. A customized mixing chamber was designed and integrated with the reformer to overcome the technical challenges of heavy hydrocarbon reformation. A thermodynamic analysis, based on total Gibbs free energy minimization, was implemented to optimize the operating environment for the reformations of various fuels. This was complimented by experimental investigations of fuel autothermal reformation. 25% biodiesel blended with 10% ethanol and 65% diesel was determined to be viable fuel for use on a truck travelling with

  1. Fusion fuel cycle solid radioactive wastes

    International Nuclear Information System (INIS)

    Gore, B.F.; Kaser, J.D.; Kabele, T.J.

    1978-06-01

    Eight conceptual deuterium-tritium fueled fusion power plant designs have been analyzed to identify waste sources, materials and quantities. All plant designs include the entire D-T fuel cycle within each plant. Wastes identified include radiation-damaged structural, moderating, and fertile materials; getter materials for removing corrosion products and other impurities from coolants; absorbents for removing tritium from ventilation air; getter materials for tritium recovery from fertile materials; vacuum pump oil and mercury sludge; failed equipment; decontamination wastes; and laundry waste. Radioactivity in these materials results primarily from neutron activation and from tritium contamination. For the designs analyzed annual radwaste volume was estimated to be 150 to 600 m 3 /GWe. This may be compared to 500 to 1300 m 3 /GWe estimated for the LMFBR fuel cycle. Major waste sources are replaced reactor structures and decontamination waste

  2. Redox Stable Anodes for Solid Oxide Fuel Cells

    Directory of Open Access Journals (Sweden)

    Guoliang eXiao

    2014-06-01

    Full Text Available Solid oxide fuel cells (SOFCs can convert chemical energy from the fuel directly to electrical energy with high efficiency and fuel flexibility. Ni-based cermets have been the most widely adopted anode for SOFCs. However, the conventional Ni-based anode has low tolerance to sulfur-contamination, is vulnerable to deactivation by carbon build-up (coking from direct oxidation of hydrocarbon fuels, and suffers volume instability upon redox cycling. Among these limitations, the redox instability of the anode is particularly important and has been intensively studied since the SOFC anode may experience redox cycling during fuel cell operations even with the ideal pure hydrogen as the fuel. This review aims to highlight recent progresses on improving redox stability of the conventional Ni-based anode through microstructure optimization and exploration of alternative ceramic-based anode materials.

  3. Integration of a municipal solid waste gasification plant with solid oxide fuel cell and gas turbine

    DEFF Research Database (Denmark)

    Bellomare, Filippo; Rokni, Masoud

    2013-01-01

    An interesting source of producing energy with low pollutants emission and reduced environmental impact are the biomasses; particularly using Municipal Solid Waste (MSW) as fuel, can be a competitive solution not only to produce energy with negligible costs but also to decrease the storage...... in landfills. A Municipal Solid Waste Gasification Plant Integrated with Solid Oxide Fuel Cell (SOFC) and Gas Turbine (GT) has been studied and the plant is called IGSG (Integrated Gasification SOFC and GT). Gasification plant is fed by MSW to produce syngas by which the anode side of an SOFC is fed wherein...

  4. Simulation methods of rocket fuel refrigerating with liquid nitrogen and intermediate heat carrier

    Directory of Open Access Journals (Sweden)

    O. E. Denisov

    2014-01-01

    Full Text Available Temperature preparation of liquid propellant components (LPC before fueling the tanks of rocket and space technology is the one of the operations performed by ground technological complexes on cosmodromes. Refrigeration of high-boiling LPC is needed to increase its density and to create cold reserve for compensation of heat flows existing during fueling and prelaunch operations of space rockets.The method and results of simulation of LPC refrigeration in the recuperative heat exchangers with heat carrier which is refrigerated by-turn with liquid nitrogen sparging. The refrigerating system consists of two tanks (for the chilled coolant and LPC, LPC and heat carrier circulation loops with heat exchanger and system of heat carrier refrigeration in its tank with bubbler. Application of intermediate heat carrier between LPC and liquid nitrogen allows to avoid LPC crystallization on cold surfaces of the heat exchanger.Simulation of such systems performance is necessary to determine its basic design and functional parameters ensuring effective refrigerating of liquid propellant components, time and the amount of liquid nitrogen spent on refrigeration operation. Creating a simulator is quite complicated because of the need to take into consideration many different heat exchange processes occurring in the system. Also, to determine the influence of various parameters on occurring processes it is necessary to take into consideration the dependence of all heat exchange parameters on each other: heat emission coefficients, heat transfer coefficients, heat flow amounts, etc.The paper offers an overview of 10 references to foreign and Russian publications on separate issues and processes occurring in liquids refrigerating, including LPC refrigeration with liquid nitrogen. Concluded the need to define the LPC refrigerating conditions to minimize cost of liquid nitrogen. The experimental data presented in these publications is conformed with the application of

  5. Solid waste generation in reprocessing nuclear fuel

    International Nuclear Information System (INIS)

    North, E.D.

    1975-01-01

    Estimates are made of the solid wastes generated annually from a 750-ton/year plant (such as the NFS West Valley plant): high-level waste, hulls, intermediate level waste, failed equipment, HEPA filters, spent solvent, alpha contaminated combustible waste, and low specific activity waste. The annual volume of each category is plotted versus the activity level

  6. SOLID STATE ENERGY CONVERSION ALLIANCE (SECA) SOLID OXIDE FUEL CELL PROGRAM

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Minh; Jim Powers

    2003-10-01

    This report summarizes the work performed for April 2003--September 2003 reporting period under Cooperative Agreement DE-FC26-01NT41245 for the U.S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid State Energy Conversion Alliance (SECA) Solid oxide Fuel Cell Program''. During this reporting period, the conceptual system design activity was completed. The system design, including strategies for startup, normal operation and shutdown, was defined. Sealant and stack materials for the solid oxide fuel cell (SOFC) stack were identified which are capable of meeting the thermal cycling and degradation requirements. A cell module was tested which achieved a stable performance of 0.238 W/cm{sup 2} at 95% fuel utilization. The external fuel processor design was completed and fabrication begun. Several other advances were made on various aspects of the SOFC system, which are detailed in this report.

  7. Rockets two classic papers

    CERN Document Server

    Goddard, Robert

    2002-01-01

    Rockets, in the primitive form of fireworks, have existed since the Chinese invented them around the thirteenth century. But it was the work of American Robert Hutchings Goddard (1882-1945) and his development of liquid-fueled rockets that first produced a controlled rocket flight. Fascinated by rocketry since boyhood, Goddard designed, built, and launched the world's first liquid-fueled rocket in 1926. Ridiculed by the press for suggesting that rockets could be flown to the moon, he continued his experiments, supported partly by the Smithsonian Institution and defended by Charles Lindbergh. T

  8. Finite element method for viscoelastic medium with damage and the application to structural analysis of solid rocket motor grain

    Science.gov (United States)

    Deng, Bin; Shen, ZhiBin; Duan, JingBo; Tang, GuoJin

    2014-05-01

    This paper studies the damage-viscoelastic behavior of composite solid propellants of solid rocket motors (SRM). Based on viscoelastic theories and strain equivalent hypothesis in damage mechanics, a three-dimensional (3-D) nonlinear viscoelastic constitutive model incorporating with damage is developed. The resulting viscoelastic constitutive equations are numerically discretized by integration algorithm, and a stress-updating method is presented by solving nonlinear equations according to the Newton-Raphson method. A material subroutine of stress-updating is made up and embedded into commercial code of Abaqus. The material subroutine is validated through typical examples. Our results indicate that the finite element results are in good agreement with the analytical ones and have high accuracy, and the suggested method and designed subroutine are efficient and can be further applied to damage-coupling structural analysis of practical SRM grain.

  9. Bioenergy in Germany. Facts and figures. Solid fuels, biofuels, biogas

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-04-11

    The brochure under consideration gives statistical information about the bioenergy in Germany: Renewable energies (bioenergy) and solid fuels. For example, the structure of the primary energy consumption in the year 2010, the energy supply from renewables, gross electricity generation, the total sales of renewables, growth in number of installed pellet boilers, wood fuel equivalent prices by energy value or biofuels in comparison with heating oil are presented.

  10. Improving the performance of solid oxide fuel cell systems

    OpenAIRE

    Halinen, Matias

    2015-01-01

    Solid oxide fuel cell (SOFC) systems can provide power production at a high electrical efficiency and with very low emissions. Furthermore, they retain their high electrical efficiency over a wide range of output power and offer good fuel flexibility, which makes them well suited for a range of applications. Currently SOFC systems are under investigation by researchers as well as being developed by industrial manufacturers. The first commercial SOFC systems have been on the market for some...

  11. Real-Time X-ray Radiography Diagnostics of Components in Solid Rocket Motors

    Science.gov (United States)

    Cortopassi, A. C.; Martin, H. T.; Boyer, E.; Kuo, K. K.

    2012-01-01

    Solid rocket motors (SRMs) typically use nozzle materials which are required to maintain their shape as well as insulate the underlying support structure during the motor operation. In addition, SRMs need internal insulation materials to protect the motor case from the harsh environment resulting from the combustion of solid propellant. In the nozzle, typical materials consist of high density graphite, carbon-carbon composites and carbon phenolic composites. Internal insulation of the motor cases is typically a composite material with carbon, asbestos, Kevlar, or silica fibers in an ablative matrix such as EPDM or NBR. For both nozzle and internal insulation materials, the charring process occurs when the hot combustion products heat the material intensely. The pyrolysis of the matrix material takes away a portion of the thermal energy near the wall surface and leaves behind a char layer. The fiber reinforcement retains the porous char layer which provides continued thermal protection from the hot combustion products. It is of great interest to characterize both the total erosion rates of the material and the char layer thickness. By better understanding of the erosion process for a particular ablative material in a specific flow environment, the required insulation material thickness can be properly selected. The recession rates of internal insulation and nozzle materials of SRMs are typically determined by testing in some sort of simulated environment; either arc-jet testing, flame torch testing, or subscale SRMs of different size. Material recession rates are deduced by comparison of pre- and post-test measurements and then averaging over the duration of the test. However, these averaging techniques cannot be used to determine the instantaneous recession rates of the material. Knowledge of the variation in recession rates in response to the instantaneous flow conditions during the motor operation is of great importance. For example, in many SRM configurations

  12. Solid Oxide Fuel Cell Stack Diagnostics

    DEFF Research Database (Denmark)

    Mosbæk, Rasmus Rode; Barfod, Rasmus Gottrup

    As SOFC technology is moving closer to a commercial break through, methods to measure the “state-of-health” of operating stacks are becoming of increasing interest. This requires application of advanced methods for detailed electrical and electrochemical characterization during operation....... An operating stack is subject to compositional gradients in the gaseous reactant streams, and temperature gradients across each cell and across the stack, which complicates detailed analysis. Several experimental stacks from Topsoe Fuel Cell A/S were characterized using Electrochemical Impedance Spectroscopy...... in the hydrogen fuel gas supplied to the stack. EIS was used to examine the long-term behavior and monitor the evolution of the impedance of each of the repeating units and the whole stack. The observed impedance was analyzed in detail for one of the repeating units and the whole stack and the losses reported...

  13. Solid fuels. Coal. Economy and resources

    International Nuclear Information System (INIS)

    Bautin, F.; Martin-Amouroux, J.M.

    2007-01-01

    The share of coal in the world energy mix (25%) and its possible increase during the next decades is due to its specific use in steelmaking industry and to its excellent competitiveness in fossil-fuel power plants with respect to other energy sources. Its inferior energy efficiency is compensated by lower and more stable prices on international markets. This situation is explained by a strong competition and abundant reserves. However, coal is a strong emitter of greenhouse gases and would be temporarily penalized by the implementation of emission tax or trading systems before the development of carbon sequestration systems. This article presents: the main world markets (consumption per sector of activity, power generation market, coke market, start-up of a synthetic fuels market), the main international coal producers and traders (overview and typology, international trades, transport), the reserves and resources, and the worldwide perspectives (2050 scenarios, climatic risks, CO 2 prices and technological changes). (J.S.)

  14. Actual directions in study of ecological consequences of a highly toxic 1,1-dimethylhydrazine-based rocket fuel spills

    Directory of Open Access Journals (Sweden)

    Bulat Kenessov

    2012-05-01

    Full Text Available The paper represents a review of the actual directions in study of ecological consequences of highly toxic 1,1-dimethylhydrazine-based rocket fuel spills. Recent results on study of processes of transformation of 1,1-dimethylhydrazine, identification of its main metabolites and development of analytical methods for their determination are generalized. Modern analytical methods of determination of 1,1-dimethylhydrazine and its transformation products in environmental samples are characterized. It is shown that in recent years, through the use of most modern methods of physical chemical analysis and sample preparation, works in this direction made significant progress and contributed to the development of studies in adjacent areas. A character of distribution of transformation products in soils of fall places of first stages of rocket-carriers is described and the available methods for their remediation are characterized.

  15. LG Solid Oxide Fuel Cell (SOFC) Model Development

    Energy Technology Data Exchange (ETDEWEB)

    Haberman, Ben [LG Fuel Cell Systems Inc., North Canton, OH (United States); Martinez-Baca, Carlos [LG Fuel Cell Systems Inc., North Canton, OH (United States); Rush, Greg [LG Fuel Cell Systems Inc., North Canton, OH (United States)

    2013-05-31

    This report presents a summary of the work performed by LG Fuel Cell Systems Inc. during the project LG Solid Oxide Fuel Cell (SOFC) Model Development (DOE Award Number: DE-FE0000773) which commenced on October 1, 2009 and was completed on March 31, 2013. The aim of this project is for LG Fuel Cell Systems Inc. (formerly known as Rolls-Royce Fuel Cell Systems (US) Inc.) (LGFCS) to develop a multi-physics solid oxide fuel cell (SOFC) computer code (MPC) for performance calculations of the LGFCS fuel cell structure to support fuel cell product design and development. A summary of the initial stages of the project is provided which describes the MPC requirements that were developed and the selection of a candidate code, STAR-CCM+ (CD-adapco). This is followed by a detailed description of the subsequent work program including code enhancement and model verification and validation activities. Details of the code enhancements that were implemented to facilitate MPC SOFC simulations are provided along with a description of the models that were built using the MPC and validated against experimental data. The modeling work described in this report represents a level of calculation detail that has not been previously available within LGFCS.

  16. Hybrid rocket motor testing at Nammo Raufoss A/S

    Science.gov (United States)

    Rønningen, Jan-Erik; Kubberud, Nils

    2005-08-01

    Hybrid rocket motor technology and the use of hybrid rockets have gained increased interest in recent years in many countries. A typical hybrid rocket consists of a tank containing the oxidizer in either liquid or gaseous state connected to the combustion chamber containing an injector, inert solid fuel grain and nozzle. Nammo Raufoss A/S has for almost 40 years designed and produced high-performance solid propellant rocket motors for many military missile systems as well as solid propellant rocket motors for civil space use. In 2003 an in-house technology program was initiated to investigate and study hybrid rocket technology. On 23 September 2004 the first in-house designed hybrid test rocket motor was static test fired at Nammo Raufoss Test Center. The oxidizer was gaseous oxygen contained in a tank pressurized to 10MPa, flow controlled through a sonic orifice into the combustion chamber containing a multi port radial injector and six bore cartridge-loaded fuel grain containing a modified HTPB fuel composition. The motor was ignited using a non-explosive heated wire. This paper will present what has been achieved at Nammo Raufoss since the start of the program.

  17. Thermal-Flow Code for Modeling Gas Dynamics and Heat Transfer in Space Shuttle Solid Rocket Motor Joints

    Science.gov (United States)

    Wang, Qunzhen; Mathias, Edward C.; Heman, Joe R.; Smith, Cory W.

    2000-01-01

    A new, thermal-flow simulation code, called SFLOW. has been developed to model the gas dynamics, heat transfer, as well as O-ring and flow path erosion inside the space shuttle solid rocket motor joints by combining SINDA/Glo, a commercial thermal analyzer. and SHARPO, a general-purpose CFD code developed at Thiokol Propulsion. SHARP was modified so that friction, heat transfer, mass addition, as well as minor losses in one-dimensional flow can be taken into account. The pressure, temperature and velocity of the combustion gas in the leak paths are calculated in SHARP by solving the time-dependent Navier-Stokes equations while the heat conduction in the solid is modeled by SINDA/G. The two codes are coupled by the heat flux at the solid-gas interface. A few test cases are presented and the results from SFLOW agree very well with the exact solutions or experimental data. These cases include Fanno flow where friction is important, Rayleigh flow where heat transfer between gas and solid is important, flow with mass addition due to the erosion of the solid wall, a transient volume venting process, as well as some transient one-dimensional flows with analytical solutions. In addition, SFLOW is applied to model the RSRM nozzle joint 4 subscale hot-flow tests and the predicted pressures, temperatures (both gas and solid), and O-ring erosions agree well with the experimental data. It was also found that the heat transfer between gas and solid has a major effect on the pressures and temperatures of the fill bottles in the RSRM nozzle joint 4 configuration No. 8 test.

  18. Chemical analysis of solid residue from liquid and solid fuel combustion: Method development and validation

    Energy Technology Data Exchange (ETDEWEB)

    Trkmic, M. [University of Zagreb, Faculty of Mechanical Engineering and Naval Architecturek Zagreb (Croatia); Curkovic, L. [University of Zagreb, Faculty of Chemical Engineering and Technology, Zagreb (Croatia); Asperger, D. [HEP-Proizvodnja, Thermal Power Plant Department, Zagreb (Croatia)

    2012-06-15

    This paper deals with the development and validation of methods for identifying the composition of solid residue after liquid and solid fuel combustion in thermal power plant furnaces. The methods were developed for energy dispersive X-ray fluorescence (EDXRF) spectrometer analysis. Due to the fuels used, the different composition and the location of creation of solid residue, it was necessary to develop two methods. The first method is used for identifying solid residue composition after fuel oil combustion (Method 1), while the second method is used for identifying solid residue composition after the combustion of solid fuels, i. e. coal (Method 2). Method calibration was performed on sets of 12 (Method 1) and 6 (Method 2) certified reference materials (CRM). CRMs and analysis test samples were prepared in pellet form using hydraulic press. For the purpose of method validation the linearity, accuracy, precision and specificity were determined, and the measurement uncertainty of methods for each analyte separately was assessed. The methods were applied in the analysis of real furnace residue samples. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Technoeconomy of different solid oxide fuel cell based hybrid cycle

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2014-01-01

    Gas turbine, steam turbine and heat engine (Stirling engine) is used as bottoming cycle for a solid oxide fuel cell plant to compare different plants efficiencies, CO2 emissionsand plants cost in terms of $/kW. Each plant is then integrated with biomass gasification and finally six plants...

  20. Kinetic and geometric aspects of solid oxide fuel cell electrodes

    DEFF Research Database (Denmark)

    Mogensen, Mogens Bjerg; Skaarup, Steen

    1996-01-01

    The paper gives an overview of the main factors controlling the performance of the solid oxide fuel cell (SOFC) electrodes, emphasizing the most widely chosen anodes and cathodes, Ni-YSZ and LSM-YSZ. They are often applied as composites (mixtures) of the electron conducting electrode material...

  1. Conversion of hydrocarbons in solid oxide fuel cells

    DEFF Research Database (Denmark)

    Mogensen, Mogens Bjerg; Kammer Hansen, K.

    2003-01-01

    Recently, a number of papers about direct oxidation of methane and hydrocarbon in solid oxide fuel cells (SOFC) at relatively low temperatures (about 700degreesC) have been published. Even though the conversion of almost dry CH4 at 1000degreesC on ceramic anodes was demonstrated more than 10 years...

  2. Quantification of fusion in ashes from solid fuel combustion

    DEFF Research Database (Denmark)

    Hansen, Lone Aslaug; Frandsen, Flemming; Dam-Johansen, Kim

    1999-01-01

    The fusion of ashes produced during solid fuel combustion greatly affects the tendency of these ashes to cause operational problems in utility boilers. In this paper, a new and quantitative laboratory method for assessing the fusion of ashes based on simultaneous thermal analysis, STA, is described...

  3. ATTACK ON WATER BY CARBON OF SOLID FUEL

    Directory of Open Access Journals (Sweden)

    N. S. Nazarov

    2008-01-01

    Full Text Available The paper considers a continuous method for attack of high temperature water steam by carbon of solid fuel (coke. Design of water-coal gas generator and experimental stand, methodology for  measurements of parameters of water-coal gasification are described in the paper.

  4. Production of Solid Fuel Briquettes from Agricultural and Wood ...

    African Journals Online (AJOL)

    Fibrous agricultural and wood waste materials have been compressed with suitable adhesive into solid fuel briquettes in a compressing machine, which was designed and constructed for this purpose. Nine samples of fibrous waste materials were prepared into different categories:- Category A (100% saw-dust, 100% ...

  5. Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Faress Rahman; Nguyen Minh

    2004-01-04

    This report summarizes the work performed by Hybrid Power Generation Systems, LLC (HPGS) during the July 2003 to December 2003 reporting period under Cooperative Agreement DE-FC26-01NT40779 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation''. The main objective of this project is to develop and demonstrate the feasibility of a highly efficient hybrid system integrating a planar Solid Oxide Fuel Cell (SOFC) and a micro-turbine. In addition, an activity included in this program focuses on the development of an integrated coal gasification fuel cell system concept based on planar SOFC technology. Also, another activity included in this program focuses on the development of SOFC scale up strategies.

  6. A development of solid oxide fuel cell technology

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Hee Chun; Lee, Chang Woo [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center; Kim, Kwy Youl; Yoon, Moon Soo; Kim, Ho Ki; Kim, Young Sik; Mun, Sung In; Eom, Sung Wuk [Korea Electrotechnology Research Inst., Changwon (Korea, Republic of)

    1995-12-31

    Solid oxide fuel cell which was consisted of ceramics has high power density and is very simple in shape. The project named A development of SOFC(Solid Oxide Fuel Cell) technology is to develop the unit cell fabrication processing and to evaluate the unit cell of solid oxide full cell. In this project, a manufacturing process of cathode by citrate method and polymeric precursor methods were established. By using tape casting method, high density thin electrolyte was manufactured and has high performance. Unit cell composed with La{sub 17}Sr{sub 13}Mn{sub 3} as cathode, 8YSZ electrolyte and 50% NiYSZ anode had a performance of O.85 W/cm{sup 2} and recorded 510 hours operation time. On the basis of these results. 100 cm{sup 2} class unit cell will be fabricated and tests in next program (author). 59 refs., 120 figs.

  7. A development of solid oxide fuel cell technology

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Hee Chun; Lee, Chang Woo [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center; Kim, Kwy Youl; Yoon, Moon Soo; Kim, Ho Ki; Kim, Young Sik; Mun, Sung In; Eom, Sung Wuk [Korea Electrotechnology Research Inst., Changwon (Korea, Republic of)

    1996-12-31

    Solid oxide fuel cell which was consisted of ceramics has high power density and is very simple in shape. The project named A development of SOFC(Solid Oxide Fuel Cell) technology is to develop the unit cell fabrication processing and to evaluate the unit cell of solid oxide full cell. In this project, a manufacturing process of cathode by citrate method and polymeric precursor methods were established. By using tape casting method, high density thin electrolyte was manufactured and has high performance. Unit cell composed with La{sub 17}Sr{sub 13}Mn{sub 3} as cathode, 8YSZ electrolyte and 50% NiYSZ anode had a performance of O.85 W/cm{sup 2} and recorded 510 hours operation time. On the basis of these results. 100 cm{sup 2} class unit cell will be fabricated and tests in next program (author). 59 refs., 120 figs.

  8. Plasma Technologies of Solid Fuels Processing

    International Nuclear Information System (INIS)

    Karpenko, E.I.; Messerle, V.E.; Ustimenko, A.

    2003-01-01

    Use of fuel processing plasma technologies improves ecological and economical indexes of low-grade coal utilization at thermal power plants. This paper presents experimental plasma plant 70 k W of power and 11 kg per hour of coal productivity. On the base of material and heat balances integral indexes of the process of plasma gasification of Podmoskovny brown coal 48% of ash content were found. Synthesis gas with concentration 85.2% was got. Hydrogen concentration in the synthesis gas was higher than carbon monoxide one. Ratio H 2 :CO in synthesis gas was 1.4-1.5. It was shown that steam consumption and temperature of the process increase causes H 2 concentration and coal gasification degree increase. Fulfilled experiments and comparison of their result with theoretical investigations allowed creating pilot experimental plant for plasma processing of low-grade coals. The power of the pilot plant is 1000 k W and coal productivity is 300 kg/h. (author)

  9. Carbonization plant for low temperature carbonization of solid fuels

    Energy Technology Data Exchange (ETDEWEB)

    1948-02-13

    A carbonization plant for the low-temperature carbonization of solid fuels, consists of a heat-treating retort including an outer vertical stationary tube, a second inner tube coaxial with the first tube, adapted to rotate round its axis and defining the first tube, and an annular gap where the solid fuel is treated. The inside of the inner tube is divided in two parts, the first fed with superheated steam which is introduced into the annular gap through vents provided in the wall of the inner tube, the second part communicating with the gap by means of vents provided in the wall of the inner tube through which gases and oil vapors evolved from the fuel are evacuated. A combustion furnace is provided in which the hot solid residues evacuated at the bottom of the annular gap are burned and from which hot fumes are evacuated, a conduit surrounding, in the form of a helical flue, outer cylinder of the retort, and in which flow hot fumes; a preliminary drier for the raw solid fuel heated by the whole or a part of the fumes evacuated from the combustion furnace. Means for bringing solid fuels from the outlet of the preliminary drier to the upper inlet of the gap of the retort a pipe line receiving steam and bringing it into the first inside part of the inner tube, this pipe line has portions located within the conduit for the fumes in order to superheat the steam, and an expansion chamber in which the gases and oil vapors are trapped at the bottom of the second inside part of the inner tube are included.

  10. The Temperature of the Dimethylhydrazine Drops Moving in the Atmosphere after Depressurization of the Fuel Tank Rockets

    Directory of Open Access Journals (Sweden)

    Bulba Elena

    2016-01-01

    Full Text Available This work includes the results of the numerical modeling of temperature changes process of the dimethylhydrazine (DMH drops, taking into account the radial temperature gradient in the air after the depressurization of the fuel compartments rockets at high altitude. There is formulated a mathematical model describing the process of DMH drops thermal state modifying when it's moving to the Earth's surface. There is the evaluation of the influence of the characteristic size of heptyl drops on the temperature distribution. It's established that the temperatures of the small size droplets practically completely coincide with the distribution of temperature in the atmosphere at altitudes of up to 40 kilometers.

  11. Identification of vapor-phase chemical warfare agent simulants and rocket fuels using laser-induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Stearns, Jaime A.; McElman, Sarah E.; Dodd, James A.

    2010-01-01

    Application of laser-induced breakdown spectroscopy (LIBS) to the identification of security threats is a growing area of research. This work presents LIBS spectra of vapor-phase chemical warfare agent simulants and typical rocket fuels. A large dataset of spectra was acquired using a variety of gas mixtures and background pressures and processed using partial least squares analysis. The five compounds studied were identified with a 99% success rate by the best method. The temporal behavior of the emission lines as a function of chamber pressure and gas mixture was also investigated, revealing some interesting trends that merit further study.

  12. Identification of vapor-phase chemical warfare agent simulants and rocket fuels using laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Stearns, Jaime A.; McElman, Sarah E.; Dodd, James A.

    2010-05-01

    Application of laser-induced breakdown spectroscopy (LIBS) to the identification of security threats is a growing area of research. This work presents LIBS spectra of vapor-phase chemical warfare agent simulants and typical rocket fuels. A large dataset of spectra was acquired using a variety of gas mixtures and background pressures and processed using partial least squares analysis. The five compounds studied were identified with a 99% success rate by the best method. The temporal behavior of the emission lines as a function of chamber pressure and gas mixture was also investigated, revealing some interesting trends that merit further study.

  13. Provisional 2008 assessment of solid mineral fuels; Bilan provisoire 2008 des combustibles mineraux solides

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-03-15

    This article first comments data on solid mineral fuel consumption in France in 2008, i.e., the overall consumption, and the consumption by different sectors (energy production in coal plants, iron and steel industry, other industries, housing and office buildings). Then, it comments solid mineral fuel imports and their origins. It comments and explains the price evolution since 1999 (notably on the Antwerp-Rotterdam-Amsterdam market) in relationship with maritime transport price, availabilities and problems, and with the evolution of coal demand (notably in China) and oil prices. Finally, it briefly comments the French residual production and stocks.

  14. Simple-1: Development stage of the data transmission system for a solid propellant mid-power rocket model

    Science.gov (United States)

    Yarce, Andrés; Sebastián Rodríguez, Juan; Galvez, Julián; Gómez, Alejandro; García, Manuel J.

    2017-06-01

    This paper presents the development stage of a communication module for a solid propellant mid-power rocket model. The communication module was named. Simple-1 and this work considers its design, construction and testing. A rocket model Estes Ventris Series Pro II® was modified to introduce, on the top of the payload, several sensors in a CanSat form factor. The Printed Circuit Board (PCB) was designed and fabricated from Commercial Off The Shelf (COTS) components and assembled in a cylindrical rack structure similar to this small format satellite concept. The sensors data was processed using one Arduino Mini and transmitted using a radio module to a Software Defined Radio (SDR) HackRF based platform on the ground station. The Simple-1 was tested using a drone in successive releases, reaching altitudes from 200 to 300 meters. Different kind of data, in terms of altitude, position, atmospheric pressure and vehicle temperature were successfully measured, making possible the progress to a next stage of launching and analysis.

  15. Modeling of Rocket Fuel Heating and Cooling Processes in the Interior Receptacle Space of Ground-Based Systems

    Directory of Open Access Journals (Sweden)

    K. I. Denisova

    2016-01-01

    Full Text Available The propellant to fill the fuel tanks of the spacecraft, upper stages, and space rockets on technical and ground-based launch sites before fueling should be prepared to ensure many of its parameters, including temperature, in appropriate condition. Preparation of fuel temperature is arranged through heating and cooling the rocket propellants (RP in the tanks of fueling equipment. Processes of RP temperature preparation are the most energy-intensive and timeconsuming ones, which require that a choice of sustainable technologies and modes of cooling (heating RP provided by the ground-based equipment has been made through modeling of the RP [1] temperature preparation processes at the stage of design and operation of the groundbased fueling equipment.The RP temperature preparation in the tanks of the ground-based systems can be provided through the heat-exchangers built-in the internal space and being external with respect to the tank in which antifreeze, air or liquid nitrogen may be used as the heat transfer media. The papers [1-12], which note a promising use of the liquid nitrogen to cool PR, present schematic diagrams and modeling systems for the RP temperature preparation in the fueling equipment of the ground-based systems.We consider the RP temperature preparation using heat exchangers to be placed directly in RP tanks. Feeding the liquid nitrogen into heat exchanger with the antifreeze provides the cooling mode of PR while a heated air fed there does that of heating. The paper gives the systems of equations and results of modeling the processes of RP temperature preparation, and its estimated efficiency.The systems of equations of cooling and heating RP are derived on the assumption that the heat exchange between the fuel and the antifreeze, as well as between the storage tank and the environment is quasi-stationary.The paper presents calculation results of the fuel temperature in the tank, and coolant temperature in the heat exchanger, as

  16. Thermal radiation modelling in a tubular solid oxide fuel cell

    International Nuclear Information System (INIS)

    Austin, M.E.; Pharoah, J.G.; Vandersteen, J.D.J.

    2004-01-01

    Solid Oxide Fuel Cells (SOFCs) are becoming the fuel cell of choice among companies and research groups interested in small power generation units. Questions still exist, however, about the operating characteristics of these devices; in particular the temperature distribution in the fuel cell. Using computational fluid dynamics (CFD) a model is proposed that incorporates conduction, convection and radiation. Both surface-to-surface and participating media are considered. It is hoped that a more accurate account of the temperature field in the various flow channels and cell components will be made to assist work on design of fuel cell components and reaction mechanisms. The model, when incorporating radiative heat transfer with participating media, predicts substantially lower operating temperatures and smaller temperature gradients than it does without these equations. It also shows the importance of the cathode air channel in cell cooling. (author)

  17. Solid fuel block as an alternate fuel for cooking and barbecuing: Preliminary results

    International Nuclear Information System (INIS)

    Sharma, Monikankana; Mukunda, H.S.; Sridhar, G.

    2009-01-01

    A large part of the rural people of developing countries use traditional biomass stoves to meet their cooking and heating energy demands. These stoves possess very low thermal efficiency; besides, most of them cannot handle agricultural wastes. Thus, there is a need to develop an alternate cooking contrivance which is simple, efficient and can handle a range of biomass including agricultural wastes. In this reported work, a highly densified solid fuel block using a range of low cost agro residues has been developed to meet the cooking and heating needs. A strategy was adopted to determine the best suitable raw materials, which was optimized in terms of cost and performance. Several experiments were conducted using solid fuel block which was manufactured using various raw materials in different proportions; it was found that fuel block composed of 40% biomass, 40% charcoal powder, 15% binder and 5% oxidizer fulfilled the requirement. Based on this finding, fuel blocks of two different configurations viz. cylindrical shape with single and multi-holes (3, 6, 9 and 13) were constructed and its performance was evaluated. For instance, the 13 hole solid fuel block met the requirement of domestic cooking; the mean thermal power was 1.6 kW th with a burn time of 1.5 h. Furthermore, the maximum thermal efficiency recorded for this particular design was 58%. Whereas, the power level of single hole solid fuel block was found to be lower but adequate for barbecue cooking application

  18. Characteristics of sustainable bio-solid fuel produced from sewage sludge as a conventional fuel substitute

    International Nuclear Information System (INIS)

    Jung, Bongjin; Nam, Wonjun; Lee, Na-Yeon; Kim, Kyung-Hoon

    2010-01-01

    Safely final disposal of sewage sludge which is being increased every year has already become serious problems. As one of the promising technologies to solve this problem, thermal drying method has been attracting wide attention due to energy recovery from sewage sludge. This paper describes several characteristics of sustainable bio-solid fuel, as a conventional fuel substitute, produced from sewage sludge drying and granulation plant having the treatment capacity of 10 ton/ day. This plant has been successfully operated many times and is now designing for scale-up. Average moisture content of twelve kinds of bio-solid fuels produced from the plant normally less than 10 wt% and average shape of them is mainly composed of granular type having a diameter of 2-8 mm for easy handling and transportation to the final market destinations. Average higher heating value, which is one of the important properties to estimate the possibility of available energy, of bio-solid fuels is about 3800 kcal/ kg as dry basis. So they can be utilized to supply energy in the coal power plant and cement kiln etc. as a conventional fuel substitute for a beneficial reuse. Characteristics including proximate analysis, ultimate analysis, contents of heavy metals, wettability etc. of bio-solid fuels have been also analyzed for the environmentally safe re utilization. (author)

  19. Structural design of an in-line bolted joint for the space shuttle solid rocket motor case segments

    Science.gov (United States)

    Dorsey, John T.; Stein, Peter A.; Bush, Harold G.

    1987-01-01

    Results of a structural design study of an in-line bolted joint concept which can be used to assemble Space Shuttle Solid Rocket Motor (SRM) case segments are presented. Numerous parametric studies are performed to characterize the in-line bolted joint behavior as major design variables are altered, with the primary objective always being to keep the inside of the joint (where the O-rings are located) closed during the SRM firing. The resulting design has 180 1-inch studs, an eccentricity of -0.5 inch, a flange thickness of 3/4 inch, a bearing plate thickness of 1/4 inch, and the studs are subjected to a preload which is 70% of ultimate. The mass penalty per case segment joint for the in-line design is 346 lbm more than the weight penalty for the proposed capture tang fix.

  20. A parallel solution-adaptive scheme for predicting multi-phase core flows in solid propellant rocket motors

    International Nuclear Information System (INIS)

    Sachdev, J.S.; Groth, C.P.T.; Gottlieb, J.J.

    2003-01-01

    The development of a parallel adaptive mesh refinement (AMR) scheme is described for solving the governing equations for multi-phase (gas-particle) core flows in solid propellant rocket motors (SRM). An Eulerian formulation is used to described the coupled motion between the gas and particle phases. A cell-centred upwind finite-volume discretization and the use of limited solution reconstruction, Riemann solver based flux functions for the gas and particle phases, and explicit multi-stage time-stepping allows for high solution accuracy and computational robustness. A Riemann problem is formulated for prescribing boundary data at the burning surface. Efficient and scalable parallel implementations are achieved with domain decomposition on distributed memory multiprocessor architectures. Numerical results are described to demonstrate the capabilities of the approach for predicting SRM core flows. (author)

  1. PRODUCTION OF NEW BIOMASS/WASTE-CONTAINING SOLID FUELS

    Energy Technology Data Exchange (ETDEWEB)

    David J. Akers; Glenn A. Shirey; Zalman Zitron; Charles Q. Maney

    2001-04-20

    CQ Inc. and its team members (ALSTOM Power Inc., Bliss Industries, McFadden Machine Company, and industry advisors from coal-burning utilities, equipment manufacturers, and the pellet fuels industry) addressed the objectives of the Department of Energy and industry to produce economical, new solid fuels from coal, biomass, and waste materials that reduce emissions from coal-fired boilers. This project builds on the team's commercial experience in composite fuels for energy production. The electric utility industry is interested in the use of biomass and wastes as fuel to reduce both emissions and fuel costs. In addition to these benefits, utilities also recognize the business advantage of consuming the waste byproducts of customers both to retain customers and to improve the public image of the industry. Unfortunately, biomass and waste byproducts can be troublesome fuels because of low bulk density, high moisture content, variable composition, handling and feeding problems, and inadequate information about combustion and emissions characteristics. Current methods of co-firing biomass and wastes either use a separate fuel receiving, storage, and boiler feed system, or mass burn the biomass by simply mixing it with coal on the storage pile. For biomass or biomass-containing composite fuels to be extensively used in the U.S., especially in the steam market, a lower cost method of producing these fuels must be developed that includes both moisture reduction and pelletization or agglomeration for necessary fuel density and ease of handling. Further, this method of fuel production must be applicable to a variety of combinations of biomass, wastes, and coal; economically competitive with current fuels; and provide environmental benefits compared with coal. Notable accomplishments from the work performed in Phase I of this project include the development of three standard fuel formulations from mixtures of coal fines, biomass, and waste materials that can be used in

  2. Solid Oxide Fuel Cells coupled with a biomass gasification unit

    Directory of Open Access Journals (Sweden)

    Skrzypkiewicz Marek

    2016-01-01

    Full Text Available A possibility of fuelling a solid oxide fuel cell stack (SOFC with biomass fuels can be realized by coupling a SOFC system with a self-standing gasification unit. Such a solution enables multi-fuel operation, elasticity of the system as well as the increase of the efficiency of small-scale biomass-to-electricity conversion units. A system of this type, consisting of biomass gasification unit, gas purification unit, SOFC stack, anode off-gas afterburner and peripherals was constructed and operated successfully. During the process, biomass fuel (wood chips was gasified with air as gasification agent. The gasifier was capable of converting up to 30 kW of fuel to syngas with efficiencies up to 75%. Syngas leaving the gasification unit is delivered to a medium temperature adsorber for sulphur compounds removal. Steam is added to the purified fuel to maintain steam to carbon ratio higher than 2. The syngas then is passed to a SOFC stack through a fuel preheater. In such a configuration it was possible to operate a commercial 1.3 kW stack within its working regime. Conducted tests confirmed successful operation of a SOFC stack fuelled by biomass-sourced syngas.

  3. Mass, energy and material balances of SRF production process. Part 3: solid recovered fuel produced from municipal solid waste.

    Science.gov (United States)

    Nasrullah, Muhammad; Vainikka, Pasi; Hannula, Janne; Hurme, Markku; Kärki, Janne

    2015-02-01

    This is the third and final part of the three-part article written to describe the mass, energy and material balances of the solid recovered fuel production process produced from various types of waste streams through mechanical treatment. This article focused the production of solid recovered fuel from municipal solid waste. The stream of municipal solid waste used here as an input waste material to produce solid recovered fuel is energy waste collected from households of municipality. This article presents the mass, energy and material balances of the solid recovered fuel production process. These balances are based on the proximate as well as the ultimate analysis and the composition determination of various streams of material produced in a solid recovered fuel production plant. All the process streams are sampled and treated according to CEN standard methods for solid recovered fuel. The results of the mass balance of the solid recovered fuel production process showed that 72% of the input waste material was recovered in the form of solid recovered fuel; 2.6% as ferrous metal, 0.4% as non-ferrous metal, 11% was sorted as rejects material, 12% as fine faction and 2% as heavy fraction. The energy balance of the solid recovered fuel production process showed that 86% of the total input energy content of input waste material was recovered in the form of solid recovered fuel. The remaining percentage (14%) of the input energy was split into the streams of reject material, fine fraction and heavy fraction. The material balances of this process showed that mass fraction of paper and cardboard, plastic (soft) and wood recovered in the solid recovered fuel stream was 88%, 85% and 90%, respectively, of their input mass. A high mass fraction of rubber material, plastic (PVC-plastic) and inert (stone/rock and glass particles) was found in the reject material stream. © The Author(s) 2014.

  4. Non-destructive delamination detection in solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Gazzarri, J.I.; Kesler, O. [Department of Mechanical Engineering, University of British Columbia, 2054-6250 Applied Science Lane, Vancouver, BC V6T 1Z4 (Canada)

    2007-05-15

    A finite element model has been developed to simulate the steady state and impedance behaviour of a single operating solid oxide fuel cell (SOFC). The model results suggest that electrode delamination can be detected minimally-invasively by using electrochemical impedance spectroscopy. The presence of cathode delamination causes changes in the cell impedance spectrum that are characteristic of this type of degradation mechanism. These changes include the simultaneous increase in both the series and polarization resistances, in proportion to the delaminated area. Parametric studies show the dependence of these changes on the extent of delamination, on the operating point, and on the kinetic characteristics of the fuel cell under study. (author)

  5. Numerical Simulations of Flow and Fuel Regression Rate Coupling in Hybrid Rocket Motors

    Directory of Open Access Journals (Sweden)

    Marius STOIA-DJESKA

    2017-03-01

    Full Text Available The hybrid propulsion offers some remarkable advantages like high safety and high specific impulse and thus it is considered a promising technology for the next generation launchers and space systems. The purpose of this work is to validate a design tool for hybrid rocket motors (HRM through numerical simulations.

  6. Modules for estimating solid waste from fossil-fuel technologies

    International Nuclear Information System (INIS)

    Crowther, M.A.; Thode, H.C. Jr.; Morris, S.C.

    1980-10-01

    Solid waste has become a subject of increasing concern to energy industries for several reasons. Increasingly stringent air and water pollution regulations result in a larger fraction of residuals in the form of solid wastes. Control technologies, particularly flue gas desulfurization, can multiply the amount of waste. With the renewed emphasis on coal utilization and the likelihood of oil shale development, increased amounts of solid waste will be produced. In the past, solid waste residuals used for environmental assessment have tended only to include total quantities generated. To look at environmental impacts, however, data on the composition of the solid wastes are required. Computer modules for calculating the quantities and composition of solid waste from major fossil fuel technologies were therefore developed and are described in this report. Six modules have been produced covering physical coal cleaning, conventional coal combustion with flue gas desulfurization, atmospheric fluidized-bed combustion, coal gasification using the Lurgi process, coal liquefaction using the SRC-II process, and oil shale retorting. Total quantities of each solid waste stream are computed together with the major components and a number of trace elements and radionuclides

  7. Pollutants generated by the combustion of solid biomass fuels

    CERN Document Server

    Jones, Jenny M; Ma, Lin; Williams, Alan; Pourkashanian, Mohamed

    2014-01-01

    This book considers the pollutants formed by the combustion of solid biomass fuels. The availability and potential use of solid biofuels is first discussed because this is the key to the development of biomass as a source of energy.This is followed by details of the methods used for characterisation of biomass and their classification.The various steps in the combustion mechanisms are given together with a compilation of the kinetic data. The chemical mechanisms for the formation of the pollutants: NOx, smoke and unburned hydrocarbons, SOx, Cl compounds, and particulate metal aerosols

  8. Micro-Solid Oxide Fuel Cell: A multi-fuel approach for portable applications

    International Nuclear Information System (INIS)

    Patil, Tarkeshwar C.; Duttagupta, Siddhartha P.

    2016-01-01

    Highlights: • We report the oxygen ion transport properties at the electrode–electrolyte interface (EEI) of the SOFC for the first time. • This ion transport plays a key role in the overall performance of SOFCs with different fuels. • The GIIB mechanism is also studied for the first time. • GIIB is assumed to be the prime reason for low power density and ion conductivity at the EEI when using hydrocarbon fuels. • Due to its scalability, a fuel cell can serve as a power source for on-chip applications and all portable equipment. - Abstract: The impact of oxygen ion transport at the electrolyte–electrode interface of a micro-solid oxide fuel cell using different fuels is investigated. Model validation is performed to verify the results versus the reported values. Furthermore, as the hydrogen-to-carbon ratio decreases, the diffusivity of the oxygen ion increases. This increase in diffusivity is observed because the number of hydrogen atoms available as the reacting species increases in fuels with lower hydrogen-to-carbon ratios. The oxygen ion conductivity and output power density decrease as the hydrogen-to-carbon ratio of the fuels decreases. The reason behind this impact is the formation of a gas-induced ion barrier at the electrode–electrolyte interface by the CO_2 molecules formed during the reaction at the interface, thus blocking the flow of oxygen ions. As the oxygen ions become blocked, the output current contribution from the reaction also decreases and thereby affects the overall performance of the micro-solid oxide fuel cell. The experimental verification confirms this because of a significant decrease in the output power density. Furthermore, as per the application in portable devices, the appropriate choice of fuel can be chosen so that the micro-solid oxide fuel cell operates at the maximum power density.

  9. Advanced Flow Analysis Tools for Transient Solid Rocket Motor Simulations, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The challenges of designing, developing, and fielding man-rated propulsion systems continue to increase as NASA's mission moves forward with evolving solid...

  10. A novel direct carbon fuel cell by approach of tubular solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Renzhu; Zhao, Chunhua; Li, Junliang; Zeng, Fanrong; Wang, Shaorong; Wen, Tinglian; Wen, Zhaoyin [CAS Key Laboratory of Materials for Energy Conversion, Shanghai Inorganic Energy Materials and Power Source Engineering Center, Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS), 1295 Dingxi Road, Shanghai 200050 (China)

    2010-01-15

    A direct carbon fuel cell based on a conventional anode-supported tubular solid oxide fuel cell, which consisted of a NiO-YSZ anode support tube, a NiO-ScSZ anode functional layer, a ScSZ electrolyte film, and a LSM-ScSZ cathode, has been successfully achieved. It used the carbon black as fuel and oxygen as the oxidant, and a preliminary examination of the DCFC has been carried out. The cell generated an acceptable performance with the maximum power densities of 104, 75, and 47 mW cm{sup -2} at 850, 800, and 750 C, respectively. These results demonstrate the feasibility for carbon directly converting to electricity in tubular solid oxide fuel cells. (author)

  11. New techniques for the characterization of refuse-derived fuels and solid recovered fuels.

    Science.gov (United States)

    Rotter, Vera Susanne; Lehmann, Annekatrin; Marzi, Thomas; Möhle, Edda; Schingnitz, Daniel; Hoffmann, Gaston

    2011-02-01

    Solid recovered fuel (SRF) today refers to a waste-derived fuel meeting defined quality specifications, in terms of both origin (produced from non-hazardous waste) and levels of certain fuel properties. Refuse-derived fuel (RDF) nowadays is more used for unspecified waste after a basic processing to increase the calorific value and therefore this term usually refers to the segregated, high calorific fraction of municipal solid waste (MSW), commercial or industrial wastes. In comparison with conventional fuels, both types of secondary fuel show waste of inherently varying quality and an increased level of waste-specific contaminants.The transition from RDF to SRF in the emerging national and European market requires a quality assurance system with defined quality parameters and analytical methods to ensure reliable fuel characterization. However, due to the quality requirements for RDF and SRF, the current standardized analysis methods often do not meet these practical demands. Fast test methods, which minimize personnel, financial and time efforts and which are applicable for producers as well as users can be an important supporting tool for RDF- and SRF-characterization. Currently, a fast test system based on incineration and correlation analyses which enable the determination of relevant fuel parameters is under development. Fast test methods are not aimed at replacing current standardized test methods, but have to be considered as practical supporting tools for the characterization of RDF and SRF.

  12. Materials for high temperature solid oxide fuel cells

    International Nuclear Information System (INIS)

    Singhal, S.C.

    1987-01-01

    High temperature solid oxide fuel cells show great promise for economical production of electricity. These cells are based upon the ability of stabilized zirconia to operate as an oxygen ion conductor at elevated temperatures. The design of the tubular solid oxide fuel cell being pursued at Westinghouse is illustrated. The cell uses a calcia-stabilized zironcia porous support tube, which acts both as a structural member onto which the other cell components are fabricated in the form of thin layers, and as a functional member to allow the passage, via its porosity, of air (or oxygen) to the air electrode. This paper summarizes the materials and fabrication processes for the various cell components

  13. Quality standards and requirements for solid recovered fuels: a review.

    Science.gov (United States)

    Flamme, Sabine; Geiping, Julia

    2012-04-01

    The utilization of solid recovered fuels (SRF) for energy recovery has been increasing steadily in recent years, and this development is set to continue. In order to use SRF efficiently, it is necessary to define quality standards and introduce targeted quality assurance measures. SRF can be used both in mono-incineration and in co-incineration systems, for instance in power generation and cement plants; but as quality requirements differ, it is necessary to unambiguously define the term 'solid recovered fuel'. The purpose of this article is to provide an overview of the origin, development and the current status of quality assurance for SRF. The basic principles of quality assurance for SRF are explained with reference to the development of the German RAL Quality Assurance System and in addition specifications that have emerged from European standardization work of CEN/TC 343 are analysed.

  14. SOLID STATE ENERGY CONVERSION ALLIANCE (SECA) SOLID OXIDE FUEL CELL PROGRAM

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2003-06-01

    This report summarizes the progress made during the September 2001-March 2002 reporting period under Cooperative Agreement DE-FC26-01NT41245 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid State Energy Conversion Alliance (SECA) Solid Oxide Fuel Cell Program''. The program focuses on the development of a low-cost, high-performance 3-to-10-kW solid oxide fuel cell (SOFC) system suitable for a broad spectrum of power-generation applications. The overall objective of the program is to demonstrate a modular SOFC system that can be configured to create highly efficient, cost-competitive, and environmentally benign power plants tailored to specific markets. When fully developed, the system will meet the efficiency, performance, life, and cost goals for future commercial power plants.

  15. Method to fabricate high performance tubular solid oxide fuel cells

    Science.gov (United States)

    Chen, Fanglin; Yang, Chenghao; Jin, Chao

    2013-06-18

    In accordance with the present disclosure, a method for fabricating a solid oxide fuel cell is described. The method includes forming an asymmetric porous ceramic tube by using a phase inversion process. The method further includes forming an asymmetric porous ceramic layer on a surface of the asymmetric porous ceramic tube by using a phase inversion process. The tube is co-sintered to form a structure having a first porous layer, a second porous layer, and a dense layer positioned therebetween.

  16. Strength of Anode‐Supported Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Faes, A.; Frandsen, Henrik Lund; Kaiser, Andreas

    2011-01-01

    Nickel oxide and yttria doped zirconia composite strength is crucial for anode‐supported solid oxide fuel cells, especially during transient operation, but also for the initial stacking process, where cell curvature after sintering can cause problems. This work first compares tensile and ball....... Even though the electrolyte is to the tensile side, it is found that the anode support fails due to the thermo‐mechanical residual stresses....

  17. Current status of Westinghouse tubular solid oxide fuel cell program

    Energy Technology Data Exchange (ETDEWEB)

    Parker, W.G. [Westinghouse Science and Technology Center, Pittsburgh, PA (United States)

    1996-04-01

    In the last ten years the solid oxide fuel cell (SOFC) development program at Westinghouse has evolved from a focus on basic material science to the engineering of fully integrated electric power systems. Our endurance for this cell is 5 to 10 years. To date we have successfully operated at power for over six years. For power plants it is our goal to have operated before the end of this decade a MW class power plant. Progress toward these goals is described.

  18. Decoupled numerical simulation of a solid fuel fired retort boiler

    International Nuclear Information System (INIS)

    Ryfa, Arkadiusz; Buczynski, Rafal; Chabinski, Michal; Szlek, Andrzej; Bialecki, Ryszard A.

    2014-01-01

    The paper deals with numerical simulation of the retort boiler fired with solid fuel. Such constructions are very popular for heating systems and their development is mostly based on the designer experience. The simulations have been done in ANSYS/Fluent package and involved two numerical models. The former deals with a fixed-bed combustion of the solid fuel and free-board gas combustion. Solid fuel combustion is based on the coal kinetic parameters. This model encompasses chemical reactions, radiative heat transfer and turbulence. Coal properties have been defined with user defined functions. The latter model describes flow of water inside a water jacked that surrounds the combustion chamber and flue gas ducts. The novelty of the proposed approach is separating of the combustion simulation from the water flow. Such approach allows for reducing the number of degrees of freedom and thus lowering the necessary numerical effort. Decoupling combustion from water flow requires defining interface boundary condition. As this boundary condition is unknown it is adjusted iteratively. The results of the numerical simulation have been successfully validated against measurement data. - Highlights: • New decoupled modelling of small scale boiler is proposed. • Fixed-bed combustion model based on kinetic parameters is introduced. • Decoupling reduced the complexity of the model and computational time. • Simple and computationally inexpensive coupling algorithm is proposed. • Model is successfully validated against measurements

  19. Characterization and Performance of a Liquid Hydrocarbon-Fueled Pulse Detonation Rocket Engine

    National Research Council Canada - National Science Library

    Damphousse, Paul

    2001-01-01

    .... The first time use of a new electro-hydraulic liquid fuel injector was demonstrated to produce consistent atomization properties while allowing for varying fuel injection durations at frequencies up to 50 Hz...

  20. 40 kW Stirling Engine for Solid Fuel

    DEFF Research Database (Denmark)

    Carlsen, Henrik; Trærup, Jens

    1996-01-01

    The external combustion in a Stirling engine makes it very attractive for utilisation of solid fuels in decentralised combined heat and power (CHP) plants. Only a few projects have concentrated on the development of Stirling engines specifically for biomass. In this project, a Stirling engine has...... been designed primarily for utilisation of wood chips. Maximum shaft power is 40 kW corresponding to an electric output of 36 kW. Biomass needs more space in the combustion chamber compared to gas and liquid fuels, and a large heat transfer area is necessary. The design of the new Stirling engine has...... been adapted to the special demands of combustion of wood chips, resulting in a large engine compared to engines for gas or liquid fuels. The engine has four-cylinders arranged in a square. The design is made as a hermetic unit, where the alternator is built into the pressurised crankcase so...

  1. Structural design considerations for micromachined solid-oxide fuel cells

    Science.gov (United States)

    Srikar, V. T.; Turner, Kevin T.; Andrew Ie, Tze Yung; Spearing, S. Mark

    Micromachined solid-oxide fuel cells (μSOFCs) are among a class of devices being investigated for portable power generation. Optimization of the performance and reliability of such devices requires robust, scale-dependent, design methodologies. In this first analysis, we consider the structural design of planar, electrolyte-supported, μSOFCs from the viewpoints of electrochemical performance, mechanical stability and reliability, and thermal behavior. The effect of electrolyte thickness on fuel cell performance is evaluated using a simple analytical model. Design diagrams that account explicitly for thermal and intrinsic residual stresses are presented to identify geometries that are resistant to fracture and buckling. Analysis of energy loss due to in-plane heat conduction highlights the importance of efficient thermal isolation in microscale fuel cell design.

  2. Solid Polymer Fuel Cells. Electrode and membrane performance studies

    Energy Technology Data Exchange (ETDEWEB)

    Moeller-Holst, S.

    1996-12-31

    This doctoral thesis studies aspects of fuel cell preparation and performance. The emphasis is placed on preparation and analysis of low platinum-loading solid polymer fuel cell (SPEC) electrodes. A test station was built and used to test cells within a wide range of real operating conditions, 40-150{sup o}C and 1-10 bar. Preparation and assembling equipment for single SPFCs was designed and built, and a new technique of spraying the catalyst layer directly onto the membrane was successfully demonstrated. Low Pt-loading electrodes (0.1 mg Pt/cm{sup 2}) prepared by the new technique exhibited high degree of catalyst utilization. The performance of single cells holding these electrodes is comparable to state-of-the-art SPFCs. Potential losses in single cell performance are ascribed to irreversibilities by analysing the efficiency of the Solid Oxide Fuel Cell by means of the second law of thermodynamics. The water management in membranes is discussed for a model system and the results are relevant to fuel cell preparation and performance. The new spray deposition technique should be commercially interesting as it involves few steps as well as techniques that are adequate for larger scale production. 115 refs., 43 figs., 18 tabs.

  3. Solid Polymer Fuel Cells. Electrode and membrane performance studies

    Energy Technology Data Exchange (ETDEWEB)

    Moeller-Holst, S

    1997-12-31

    This doctoral thesis studies aspects of fuel cell preparation and performance. The emphasis is placed on preparation and analysis of low platinum-loading solid polymer fuel cell (SPEC) electrodes. A test station was built and used to test cells within a wide range of real operating conditions, 40-150{sup o}C and 1-10 bar. Preparation and assembling equipment for single SPFCs was designed and built, and a new technique of spraying the catalyst layer directly onto the membrane was successfully demonstrated. Low Pt-loading electrodes (0.1 mg Pt/cm{sup 2}) prepared by the new technique exhibited high degree of catalyst utilization. The performance of single cells holding these electrodes is comparable to state-of-the-art SPFCs. Potential losses in single cell performance are ascribed to irreversibilities by analysing the efficiency of the Solid Oxide Fuel Cell by means of the second law of thermodynamics. The water management in membranes is discussed for a model system and the results are relevant to fuel cell preparation and performance. The new spray deposition technique should be commercially interesting as it involves few steps as well as techniques that are adequate for larger scale production. 115 refs., 43 figs., 18 tabs.

  4. SOLID OXIDE FUEL CELL HYBRID SYSTEM FOR DISTRIBUTED POWER GENERATION

    Energy Technology Data Exchange (ETDEWEB)

    Faress Rahman; Nguyen Minh

    2003-07-01

    This report summarizes the work performed by Hybrid Power Generation Systems, LLC during the January 2003 to June 2003 reporting period under Cooperative Agreement DE-FC26-01NT40779 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation''. The main objective of this project is to develop and demonstrate the feasibility of a highly efficient hybrid system integrating a planar Solid Oxide Fuel Cell (SOFC) and a micro-turbine. In addition, an activity included in this program focuses on the development of an integrated coal gasification fuel cell system concept based on planar SOFC technology. This report summarizes the results obtained to date on: System performance analysis and model optimization; Reliability and cost model development; System control including dynamic model development; Heat exchanger material tests and life analysis; Pressurized SOFC evaluation; and Pre-baseline system definition for coal gasification fuel cell system concept.

  5. Production of gaseous or vaporous fuels from solid carbonaceous materials

    Energy Technology Data Exchange (ETDEWEB)

    1951-05-16

    A process for the production of gaseous or vaporous fuels from solid carbonaceous materials consists of subjecting the materials in separate zones to at least three successive thermal treatments at least two of which are carried out at different temperature levels. The materials being maintained in zones in the form of beds of finely divided particles fluidized by the passage of gases or vapors upwardly there-through, and recovering product vapors or gases overhead. The total hot gaseous or vaporous effluent and entrained solids from one of the zones is passed directly without separation to another of the zones situated closely adjacent to and vertically above the first named zone in the same vessel, and the heat required in at least one of the thermal treatment zones is supplied at least in part as the sensible heat of residual solids transferred from a thermal treatment zone operated at a higher temperature.

  6. Three-dimensional multi-physics coupled simulation of ignition transient in a dual pulse solid rocket motor

    Science.gov (United States)

    Li, Yingkun; Chen, Xiong; Xu, Jinsheng; Zhou, Changsheng; Musa, Omer

    2018-05-01

    In this paper, numerical investigation of ignition transient in a dual pulse solid rocket motor has been conducted. An in-house code has been developed in order to solve multi-physics governing equations, including unsteady compressible flow, heat conduction and structural dynamic. The simplified numerical models for solid propellant ignition and combustion have been added. The conventional serial staggered algorithm is adopted to simulate the fluid structure interaction problems in a loosely-coupled manner. The accuracy of the coupling procedure is validated by the behavior of a cantilever panel subjected to a shock wave. Then, the detailed flow field development, flame propagation characteristics, pressure evolution in the combustion chamber, and the structural response of metal diaphragm are analyzed carefully. The burst-time and burst-pressure of the metal diaphragm are also obtained. The individual effects of the igniter's mass flow rate, metal diaphragm thickness and diameter on the ignition transient have been systemically compared. The numerical results show that the evolution of the flow field in the combustion chamber, the temperature distribution on the propellant surface and the pressure loading on the metal diaphragm surface present a strong three-dimensional behavior during the initial ignition stage. The rupture of metal diaphragm is not only related to the magnitude of pressure loading on the diaphragm surface, but also to the history of pressure loading. The metal diaphragm thickness and diameter have a significant effect on the burst-time and burst-pressure of metal diaphragm.

  7. Artificial neural networks application for solid fuel slagging intensity predictions

    Directory of Open Access Journals (Sweden)

    Kakietek Sławomir

    2017-01-01

    Full Text Available Slagging issues present in pulverized steam boilers very often lead to heat transfer problems, corrosion and not planned outages of boilers which increase the cost of energy production and decrease the efficiency of energy production. Slagging especially occurs in regions with reductive atmospheres which nowadays are very common due to very strict limitations in NOx emissions. Moreover alternative fuels like biomass which are also used in combustion systems from two decades in order to decrease CO2 emissions also usually increase the risk of slagging. Thus the prediction of slagging properties of fuels is not the minor issue which can be neglected before purchasing or mixing of fuels. This however is rather difficult to estimate and even commonly known standard laboratory methods like fusion temperature determination or special indexers calculated on the basis of proximate and ultimate analyses, very often have no reasonable correlation to real boiler fuel behaviour. In this paper the method of determination of slagging properties of solid fuels based on laboratory investigation and artificial neural networks were presented. A fuel data base with over 40 fuels was created. Neural networks simulations were carried out in order to predict the beginning temperature and intensity of slagging. Reasonable results were obtained for some of tested neural networks, especially for hybrid feedforward networks with PCA technique. Consequently neural network model will be used in Common Intelligent Boiler Operation Platform (CIBOP being elaborated within CERUBIS research project for two BP-1150 and BB-1150 steam boilers. The model among others enables proper fuel selection in order to minimize slagging risk.

  8. Thermodynamic analysis of SOFC (solid oxide fuel cell)–Stirling hybrid plants using alternative fuels

    International Nuclear Information System (INIS)

    Rokni, Masoud

    2013-01-01

    A novel hybrid power system (∼10 kW) for an average family home is proposed. The system investigated contains a solid oxide fuel cell (SOFC) on top of a Stirling engine. The off-gases produced in the SOFC cycle are fed to a bottoming Stirling engine, at which additional power is generated. Simulations of the proposed system were conducted using different fuels, which should facilitate the use of a variety of fuels depending on availability. Here, the results for natural gas (NG), ammonia, di-methyl ether (DME), methanol and ethanol are presented and analyzed. The system behavior is further investigated by comparing the effects of key factors, such as the utilization factor and the operating conditions under which these fuels are used. Moreover, the effect of using a methanator on the plant efficiency is also studied. The combined system improves the overall electrical efficiency relative to that of a stand-alone Stirling engine or SOFC plant. For the combined SOFC and Stirling configuration, the overall power production was increased by approximately 10% compared to that of a stand-alone SOFC plant. System efficiencies of approximately 60% are achieved, which is remarkable for such small plant sizes. Additionally, heat is also produced to heat the family home when necessary. - Highlights: • Integrating a solid oxide fuel with a Stirling engine • Design of multi-fuel hybrid plants • Plants running on alternative fuels; natural gas, methanol, ethanol, DME and ammonia • Thermodynamic analysis of hybrid SOFC–Stirling engine plants

  9. The development of a solid-state hydrogen sensor for rocket engine leakage detection

    Science.gov (United States)

    Liu, Chung-Chiun

    1994-01-01

    Hydrogen propellant leakage poses significant operational problems in the rocket propulsion industry as well as for space exploratory applications. Vigorous efforts have been devoted to minimizing hydrogen leakage in assembly, test, and launch operations related to hydrogen propellant. The objective has been to reduce the operational cost of assembling and maintaining hydrogen delivery systems. Specifically, efforts have been made to develop a hydrogen leak detection system for point-contact measurement. Under the auspices of Lewis Research Center, the Electronics Design Center at Case Western Reserve University, Cleveland, Ohio, has undertaken the development of a point-contact hydrogen gas sensor with potential applications to the hydrogen propellant industry. We envision a sensor array consisting of numbers of discrete hydrogen sensors that can be located in potential leak sites. Silicon-based microfabrication and micromachining techniques are used in the fabrication of these sensor prototypes. Evaluations of the sensor are carried out in-house at Case Western Reserve University as well as at Lewis Research Center and GenCorp Aerojet, Sacramento, California. The hydrogen gas sensor is not only applicable in a hydrogen propulsion system, but also usable in many other civilian and industrial settings. This includes vehicles or facility use, or in the production of hydrogen gas. Dual space and commercial uses of these point-contacted hydrogen sensors are feasible and will directly meet the needs and objectives of NASA as well as various industrial segments.

  10. The development of a solid-state hydrogen sensor for rocket engine leakage detection

    Science.gov (United States)

    Liu, Chung-Chiun

    Hydrogen propellant leakage poses significant operational problems in the rocket propulsion industry as well as for space exploratory applications. Vigorous efforts have been devoted to minimizing hydrogen leakage in assembly, test, and launch operations related to hydrogen propellant. The objective has been to reduce the operational cost of assembling and maintaining hydrogen delivery systems. Specifically, efforts have been made to develop a hydrogen leak detection system for point-contact measurement. Under the auspices of Lewis Research Center, the Electronics Design Center at Case Western Reserve University, Cleveland, Ohio, has undertaken the development of a point-contact hydrogen gas sensor with potential applications to the hydrogen propellant industry. We envision a sensor array consisting of numbers of discrete hydrogen sensors that can be located in potential leak sites. Silicon-based microfabrication and micromachining techniques are used in the fabrication of these sensor prototypes. Evaluations of the sensor are carried out in-house at Case Western Reserve University as well as at Lewis Research Center and GenCorp Aerojet, Sacramento, California. The hydrogen gas sensor is not only applicable in a hydrogen propulsion system, but also usable in many other civilian and industrial settings. This includes vehicles or facility use, or in the production of hydrogen gas. Dual space and commercial uses of these point-contacted hydrogen sensors are feasible and will directly meet the needs and objectives of NASA as well as various industrial segments.

  11. Solid propellant ignition motors for LH_2/LOX rocket engine system

    OpenAIRE

    ARAKI, Tetsuo; AKIBA, Ryojiro; HASHIMOTO, Yasunari; AIHARA, Kenji; TOMITA, Etsu; YASUDA, Seiichi; 荒木, 哲夫; 秋葉, 鐐二郎; 橋本, 保成; 相原, 賢二; 富田, 悦; 安田, 誠一

    1983-01-01

    Solid propellant ignition motors are used in the series of experiments of the 10 ton LH_2/LOX engine featured by the channel wall thrust chamber, This paper presents design specification, experiments and results obtained by actual applications of those ignition motors.

  12. Degradation of solid oxide fuel cell metallic interconnects in fuels containing sulfur

    Energy Technology Data Exchange (ETDEWEB)

    Ziomek-Moroz, M.; Hawk, Jeffrey A.

    2005-01-01

    Hydrogen is the main fuel for all types of fuel cells except direct methanol fuel cells. Hydrogen can be generated from all manner of fossil fuels, including coal, natural gas, diesel, gasoline, other hydrocarbons, and oxygenates (e.g., methanol, ethanol, butanol, etc.). Impurities in the fuel can cause significant performance problems and sulfur, in particular, can decrease the cell performance of fuel cells, including solid oxide fuel cells (SOFC). In the SOFC, the high (800-1000°C) operating temperature yields advantages (e.g., internal fuel reforming) and disadvantages (e.g., material selection and degradation problems). Significant progress in reducing the operating temperature of the SOFC from ~1000 ºC to ~750 ºC may allow less expensive metallic materials to be used for interconnects and as balance of plant (BOP) materials. This paper provides insight on the material performance of nickel, ferritic steels, and nickel-based alloys in fuels containing sulfur, primarily in the form of H2S, and seeks to quantify the extent of possible degradation due to sulfur in the gas stream.

  13. Operation of real landfill gas fueled solid oxide fuel cell (SOFC) using internal dry reforming

    DEFF Research Database (Denmark)

    Langnickel, Hendrik; Hagen, Anke

    2017-01-01

    Biomass is one renewable energy source, which is independent from solar radiation and wind effect. Solid oxide fuel cells (SOFC’s) are able to convert landfill gas derived from landfill directly into electricity and heat with a high efficiency. In the present work a planar 16cm2 SOFC cell...... was necessary to prevent poisoning and thereby to decrease the degradation rate....

  14. Hydrothermal treatment of grape marc for solid fuel applications

    International Nuclear Information System (INIS)

    Mäkelä, Mikko; Kwong, Chi Wai; Broström, Markus; Yoshikawa, Kunio

    2017-01-01

    Highlights: • The effects of treatment temperature and liquid pH on char and liquid properties. • Liquid pH had a statistically significant effect only on liquid carbon yield. • Higher treatment temperature increased char volatiles that can enhance ignitability. • Char showed promising fuel properties if elevated ash phosphorus can be tolerated. - Abstract: The treatment and disposal of grape marc, a residue from grape processing, represents a significant economic and environmental challenge for the winemaking industry. Hydrothermal treatment of grape marc could be an efficient way for producing solid fuels on-site at the wineries. In this work the effects of treatment temperature and liquid pH on grape marc char and liquid properties were determined based on laboratory experiments and the combustion characteristics of char were assessed through thermogravimetric analysis and fuel ash classification. The results showed that hydrothermal treatment increased the energy and carbon contents and decreased the ash content of grape marc. The effect of liquid pH was statistically significant (p < 0.05) only for the determined carbon yield of liquid samples. The energy yield from grape marc was maximized at lower treatment temperatures, which also decreased the content of less thermally stable compounds in the attained char. Higher treatment temperatures decreased grape marc solid, carbon and energy yields and led to an increase in thermally labile compounds compared to lower temperatures likely due to the condensation of liquid compounds or volatiles trapped in the pores of char particles. The alkali metal contents of char ash were reduced coupled with an increase in respective phosphorus. Overall the results support the use of hydrothermally treated grape marc in solid fuel applications, if elevated levels of ash phosphorus can be tolerated.

  15. High temperature fuel cell with ceria-based solid electrolyte

    International Nuclear Information System (INIS)

    Arai, H.; Eguchi, K.; Yahiro, H.; Baba, Y.

    1987-01-01

    Cation-doped ceria is investigated as an electrolyte for the solid oxide fuel cell. As for application to the fuel cells, the electrolyte are desired to have high ionic conductivity in deriving a large electrical power. A series of cation-doped ceria has higher ionic conductivity than zirconia-based oxides. In the present study, the basic electrochemical properties of cation-doped ceria were studied in relation to the application of fuel cells. The performance of fuel cell with yttria-doped ceria electrolyte was evaluated. Ceria-based oxides were prepared by calcination of oxide mixtures of the components or calcination of co-precipitated hydroxide mixtures from the metal nitrate solution. The oxide mixtures thus obtained were sintered at 1650 0 C for 15 hr in air into disks. Ionic transference number, t/sub i/, was estimated from emf of oxygen concentration cell. Electrical conductivities were measured by dc-4 probe method by varying the oxygen partial pressure. The fuel cell was operated by oxygen and hydrogen

  16. Compact hydrogen production systems for solid polymer fuel cells

    Science.gov (United States)

    Ledjeff-Hey, K.; Formanski, V.; Kalk, Th.; Roes, J.

    Generally there are several ways to produce hydrogen gas from carbonaceous fuels like natural gas, oil or alcohols. Most of these processes are designed for large-scale industrial production and are not suitable for a compact hydrogen production system (CHYPS) in the power range of 1 kW. In order to supply solid polymer fuel cells (SPFC) with hydrogen, a compact fuel processor is required for mobile applications. The produced hydrogen-rich gas has to have a low level of harmful impurities; in particular the carbon monoxide content has to be lower than 20 ppmv. Integrating the reaction step, the gas purification and the heat supply leads to small-scale hydrogen production systems. The steam reforming of methanol is feasible at copper catalysts in a low temperature range of 200-350°C. The combination of a small-scale methanol reformer and a metal membrane as purification step forms a compact system producing high-purity hydrogen. The generation of a SPFC hydrogen fuel gas can also be performed by thermal or catalytic cracking of liquid hydrocarbons such as propane. At a temperature of 900°C the decomposition of propane into carbon and hydrogen takes place. A fuel processor based on this simple concept produces a gas stream with a hydrogen content of more than 90 vol.% and without CO and CO2.

  17. Econometric comparisons of liquid rocket engines for dual-fuel advanced earth-to-orbit shuttles

    Science.gov (United States)

    Martin, J. A.

    1978-01-01

    Econometric analyses of advanced Earth-to-orbit vehicles indicate that there are economic benefits from development of new vehicles beyond the space shuttle as traffic increases. Vehicle studies indicate the advantage of the dual-fuel propulsion in single-stage vehicles. This paper shows the economic effect of incorporating dual-fuel propulsion in advanced vehicles. Several dual-fuel propulsion systems are compared to a baseline hydrogen and oxygen system.

  18. Common Cause Case Study: An Estimated Probability of Four Solid Rocket Booster Hold-Down Post Stud Hang-ups

    Science.gov (United States)

    Cross, Robert

    2005-01-01

    Until Solid Rocket Motor ignition, the Space Shuttle is mated to the Mobil Launch Platform in part via eight (8) Solid Rocket Booster (SRB) hold-down bolts. The bolts are fractured using redundant pyrotechnics, and are designed to drop through a hold-down post on the Mobile Launch Platform before the Space Shuttle begins movement. The Space Shuttle program has experienced numerous failures where a bolt has hung up. That is, it did not clear the hold-down post before liftoff and was caught by the SRBs. This places an additional structural load on the vehicle that was not included in the original certification requirements. The Space Shuttle is currently being certified to withstand the loads induced by up to three (3) of eight (8) SRB hold-down experiencing a "hang-up". The results of loads analyses performed for (4) stud hang-ups indicate that the internal vehicle loads exceed current structural certification limits at several locations. To determine the risk to the vehicle from four (4) stud hang-ups, the likelihood of the scenario occurring must first be evaluated. Prior to the analysis discussed in this paper, the likelihood of occurrence had been estimated assuming that the stud hang-ups were completely independent events. That is, it was assumed that no common causes or factors existed between the individual stud hang-up events. A review of the data associated with the hang-up events, showed that a common factor (timing skew) was present. This paper summarizes a revised likelihood evaluation performed for the four (4) stud hang-ups case considering that there are common factors associated with the stud hang-ups. The results show that explicitly (i.e. not using standard common cause methodologies such as beta factor or Multiple Greek Letter modeling) taking into account the common factor of timing skew results in an increase in the estimated likelihood of four (4) stud hang-ups of an order of magnitude over the independent failure case.

  19. Strategies for Lowering Solid Oxide Fuel Cells Operating Temperature

    Directory of Open Access Journals (Sweden)

    Albert Tarancón

    2009-11-01

    Full Text Available Lowering the operating temperature of solid oxide fuel cells (SOFCs to the intermediate range (500–700 ºC has become one of the main SOFC research goals. High operating temperatures put numerous requirements on materials selection and on secondary units, limiting the commercial development of SOFCs. The present review first focuses on the main effects of reducing the operating temperature in terms of materials stability, thermo-mechanical mismatch, thermal management and efficiency. After a brief survey of the state-of-the-art materials for SOFCs, attention is focused on emerging oxide-ionic conductors with high conductivity in the intermediate range of temperatures with an introductory section on materials technology for reducing the electrolyte thickness. Finally, recent advances in cathode materials based on layered mixed ionic-electronic conductors are highlighted because the decreasing temperature converts the cathode into the major source of electrical losses for the whole SOFC system. It is concluded that the introduction of alternative materials that would enable solid oxide fuel cells to operate in the intermediate range of temperatures would have a major impact on the commercialization of fuel cell technology.

  20. Indoor air pollution from unprocessed solid fuels in developing countries.

    Science.gov (United States)

    Kaplan, Charlotte

    2010-01-01

    Approximately half of the world's population relies on biomass (primarily wood and agricultural residues) or coal fuels (collectively termed solid fuels) for heating, lighting, and cooking. The incomplete combustion of such materials releases byproducts with well-known adverse health effects, hence increasing the risk of many diseases and death. Among these conditions are acute respiratory infections, chronic obstructive pulmonary disease, heart disease, stroke, lung cancer, cataracts and blindness, tuberculosis, asthma, and adverse pregnancy outcomes. The International Agency for Research on Cancer has classified the indoor combustion of coal emissions as Group 1, a known carcinogen to humans. Indoor air pollution exposure is greatest in individuals who live in rural developing countries. Interventions have been limited and show only mixed results. To reduce the morbidity and mortality from indoor air pollution, countermeasures have to be developed that are practical, efficient, sustainable, and economical with involvement from the government, the commercial sector, and individuals. This review focuses on the contribution of solid fuels to indoor air pollution.

  1. Performance analysis of hybrid solid oxide fuel cell and gas turbine cycle: Application of alternative fuels

    International Nuclear Information System (INIS)

    Zabihian, Farshid; Fung, Alan S.

    2013-01-01

    Highlights: • Variation of the stream properties in the syngas-fueled hybrid SOFC–GT cycle. • Detailed analysis of the operation of the methane-fueled SOFC–GT cycle. • Investigate effects of inlet fuel type and composition on performance of cycle. • Comparison of system operation when operated with and without anode recirculation. - Abstract: In this paper, the hybrid solid oxide fuel cell (SOFC) and gas turbine (GT) model was applied to investigate the effects of the inlet fuel type and composition on the performance of the cycle. This type of analysis is vital for the real world utilization of manufactured fuels in the hybrid SOFC–GT system due to the fact that these fuel compositions depends on the type of material that is processed, the fuel production process, and process control parameters. In the first part of this paper, it is shown that the results of a limited number of studies on the utilization of non-conventional fuels have been published in the open literature. However, further studies are required in this area to investigate all aspects of the issue for different configurations and assumptions. Then, the results of the simulation of the syngas-fueled hybrid SOFC–GT cycle are employed to explain the variation of the stream properties throughout the cycle. This analysis can be very helpful in understanding cycle internal working and can provide some interesting insights to the system operation. Then, the detailed information of the operation of the methane-fueled SOFC–GT cycle is presented. For both syngas- and methane-fueled cycles, the operating conditions of the equipment are presented and compared. Moreover, the comparison of the characteristics of the system when it is operated with two different schemes to provide the required steam for the cycle, with anode recirculation and with an external source of water, provides some interesting insights to the system operation. For instance, it was shown that although the physical

  2. Development of a solid oxide fuel cell (SOFC) automotive auxiliary power unit (APU) fueled by gasoline

    International Nuclear Information System (INIS)

    DeMinco, C.; Mukerjee, S.; Grieve, J.; Faville, M.; Noetzel, J.; Perry, M.; Horvath, A.; Prediger, D.; Pastula, M.; Boersma, R.; Ghosh, D.

    2000-01-01

    This paper describes the design and the development progress of a 3 to 5 auxiliary power unit (APU) based on a gasoline fueled solid oxide fuel cell (SOFC). This fuel cell was supplied reformate gas (reactant) by a partial oxidation (POx) catalytic reformer utilizing liquid gasoline and designed by Delphi Automotive Systems. This reformate gas consists mainly of hydrogen, carbon monoxide and nitrogen and was fed directly in to the SOFC stack without any additional fuel reformer processing. The SOFC stack was developed by Global Thermoelectric and operates around 700 o C. This automotive APU produces power to support future 42 volt vehicle electrical architectures and loads. The balance of the APU, designed by Delphi Automotive Systems, employs a packaging and insulation design to facilitate installation and operation on-board automobiles. (author)

  3. Solid State Energy Conversion Alliance (SECA) Solid Oxide Fuel Cell Program

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Minh

    2006-07-31

    This report summarizes the work performed for Phase I (October 2001 - August 2006) under Cooperative Agreement DE-FC26-01NT41245 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled 'Solid State Energy Conversion Alliance (SECA) Solid Oxide Fuel Cell Program'. The program focuses on the development of a low-cost, high-performance 3-to-10-kW solid oxide fuel cell (SOFC) system suitable for a broad spectrum of power-generation applications. During Phase I of the program significant progress has been made in the area of SOFC technology. A high-efficiency low-cost system was designed and supporting technology developed such as fuel processing, controls, thermal management, and power electronics. Phase I culminated in the successful demonstration of a prototype system that achieved a peak efficiency of 41%, a high-volume cost of $724/kW, a peak power of 5.4 kW, and a degradation rate of 1.8% per 500 hours. . An improved prototype system was designed, assembled, and delivered to DOE/NETL at the end of the program. This prototype achieved an extraordinary peak efficiency of 49.6%.

  4. PREPARATION AND CHARACTERIZATION OF SOLID ELECTROLYTES: FUEL CELL APPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Rambabu Bobba; Josef Hormes; T. Wang; Jaymes A. Baker; Donald G. Prier; Tommy Rockwood; Dinesha Hawkins; Saleem Hasan; V. Rayanki

    1997-12-31

    The intent of this project with Federal Energy Technology Center (FETC)/Morgantown Energy Technology Center (METC) is to develop research infrastructure conductive to Fuel Cell research at Southern University and A and M College, Baton Route. A state of the art research laboratory (James Hall No.123 and No.114) for energy conversion and storage devices was developed during this project duration. The Solid State Ionics laboratory is now fully equipped with materials research instruments: Arbin Battery Cycling and testing (8 channel) unit, Electrochemical Analyzer (EG and G PAR Model 273 and Solartron AC impedance analyzer), Fuel Cell test station (Globe Tech), Differential Scanning Calorimeter (DSC-10), Thermogravimetric Analyzer (TGA), Scanning Tunneling Microscope (STM), UV-VIS-NIR Absorption Spectrometer, Fluorescence Spectrometer, FT-IR Spectrometer, Extended X-ray Absorption Fine Structure (EXAFS) measurement capability at Center for Advanced Microstructure and Devices (CAMD- a multimillion dollar DOE facility), Glove Box, gas hood chamber, high temperature furnaces, hydraulic press and several high performance computers. IN particular, a high temperature furnace (Thermodyne 6000 furnace) and a high temperature oven were acquired through this project funds. The PI Dr. R Bobba has acquired additional funds from federal agencies include NSF-Academic Research Infrastructure program and other DOE sites. They have extensively used the multimillion dollar DOE facility ''Center'' for Advanced Microstructures and Devices (CAMD) for electrochemical research. The students were heavily involved in the experimental EXAFS measurements and made use of their DCM beamline for EXAFS research. The primary objective was to provide hands on experience to the selected African American undergraduate and graduate students in experimental energy research.The goal was to develop research skills and involve them in the Preparation and Characterization of Solid

  5. AlliedSignal solid oxide fuel cell technology

    Energy Technology Data Exchange (ETDEWEB)

    Minh, N.; Barr, K.; Kelly, P.; Montgomery, K. [AlliedSignal Aerospace Equipment Systems, Torrance, CA (United States)

    1996-12-31

    AlliedSignal has been developing high-performance, lightweight solid oxide fuel cell (SOFC) technology for a broad spectrum of electric power generation applications. This technology is well suited for use in a variety of power systems, ranging from commercial cogeneration to military mobile power sources. The AlliedSignal SOFC is based on stacking high-performance thin-electrolyte cells with lightweight metallic interconnect assemblies to form a compact structure. The fuel cell can be operated at reduced temperatures (600{degrees} to 800{degrees}C). SOFC stacks based on this design has the potential of producing 1 kW/kg and 1 ML. This paper summarizes the technical status of the design, manufacture, and operation of AlliedSignal SOFCs.

  6. Planar solid oxide fuel cells: the Australian experience and outlook

    Science.gov (United States)

    Godfrey, Bruce; Föger, Karl; Gillespie, Rohan; Bolden, Roger; Badwal, S. P. S.

    Since 1992, Ceramic Fuel Cells (CFCL) has grown to what is now the largest focussed program globally for development of planar ceramic (solid oxide) fuel cell, SOFC, technology. A significant intellectual property position in know-how and patents has been developed, with over 80 people involved in the venture. Over $A60 million in funding for the activities of the company has been raised from private companies, government-owned corporations and government business-support programs, including from energy — particularly electricity — industry shareholders that can facilitate access to local markets for our products. CFCL has established state-of-the-art facilities for planar SOFC R&D, with their expansion and scaling-up to pilot manufacturing capability underway. We expect to achieve commercial introduction of our market-entry products in 2002, with prototype systems expected to be available from early 2001.

  7. Thermal stress analysis of sulfur deactivated solid oxide fuel cells

    Science.gov (United States)

    Zeng, Shumao; Parbey, Joseph; Yu, Guangsen; Xu, Min; Li, Tingshuai; Andersson, Martin

    2018-03-01

    Hydrogen sulfide in fuels can deactivate catalyst for solid oxide fuel cells, which has become one of the most critical challenges to stability. The reactions between sulfur and catalyst will cause phase changes, leading to increase in cell polarization and mechanical mismatch. A three-dimensional computational fluid dynamics (CFD) approach based on the finite element method (FEM) is thus used to investigate the polarization, temperature and thermal stress in a sulfur deactivated SOFC by coupling equations for gas-phase species, heat, momentum, ion and electron transport. The results indicate that sulfur in fuels can strongly affect the cell polarization and thermal stresses, which shows a sharp decrease in the vicinity of electrolyte when 10% nickel in the functional layer is poisoned, but they remain almost unchanged even when the poisoned Ni content was increased to 90%. This investigation is helpful to deeply understand the sulfur poisoning effects and also benefit the material design and optimization of electrode structure to enhance cell performance and lifetimes in various hydrocarbon fuels containing impurities.

  8. Alternative anode materials for solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Goodenough, John B.; Huang, Yun-Hui [Texas Materials Institute, ETC 9.102, 1 University Station, C2200, The University of Texas at Austin, Austin, TX 78712 (United States)

    2007-11-08

    The electrolyte of a solid oxide fuel cell (SOFC) is an O{sup 2-}-ion conductor. The anode must oxidize the fuel with O{sup 2-} ions received from the electrolyte and it must deliver electrons of the fuel chemisorption reaction to a current collector. Cells operating on H{sub 2} and CO generally use a porous Ni/electrolyte cermet that supports a thin, dense electrolyte. Ni acts as both the electronic conductor and the catalyst for splitting the H{sub 2} bond; the oxidation of H{sub 2} to H{sub 2}O occurs at the Ni/electrolyte/H{sub 2} triple-phase boundary (TPB). The CO is oxidized at the oxide component of the cermet, which may be the electrolyte, yttria-stabilized zirconia, or a mixed oxide-ion/electron conductor (MIEC). The MIEC is commonly a Gd-doped ceria. The design and fabrication of these anodes are evaluated. Use of natural gas as the fuel requires another strategy, and MIECs are being explored for this application. The several constraints on these MIECs are outlined, and preliminary results of this on-going investigation are reviewed. (author)

  9. Mathematical model for solid fuel combustion in fluidized bed

    International Nuclear Information System (INIS)

    Kostikj, Zvonimir; Noshpal, Aleksandar

    1994-01-01

    A mathematical model for computation of the combustion process of solid fuel in fluidized bed is presented in this work. Only the combustor part of the plant (the fluidized bed and the free board) is treated with this model. In that manner, all principal, physical presumption and improvements (upon which this model is based) are given. Finally, the results of the numerical realisation of the mathematical model for combustion of minced straw as well as the results of the experimental investigation of a concrete physical model are presented. (author)

  10. Lanthanum Manganate Based Cathodes for Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Jørgensen, Mette Juhl

    Composite cathodes for solid oxide fuel cells were investigated using electrochemical impedance spectroscopy and scanning electron microscopy. The aim was to study the oxygen reduction process in the electrode in order to minimise the voltage drop in the cathode. The electrodes contained...... five processes were found to affect the impedance of LSM/YSZ composite electrodes. Two high frequency processes were ascribed to transport of oxide ions/oxygen intermediates across LSM/YSZ interfaces and through YSZ in the composite. Several competitive elementary reaction steps, which appear as one...

  11. Solid polymer fuel cell stationary power generation design studies

    Energy Technology Data Exchange (ETDEWEB)

    Pyke, S.H.; Wood, A.; Williams, G.J.; Kearney, P.

    2000-07-01

    This report summarises the results of a study investigating potential markets for solid polymer fuel cells (SPFC) stationary power generating systems and evaluating design options for grid connected and stand-alone systems. The specification of potential application for SPFC systems, initial modelling and economic analysis of twelve candidate SPFC applications, and the ranking and evaluation of candidate applications are examined. Details are given of performance modelling and economic analysis of four preferred SPFC systems (domestic, commercial, light industrial, and transportable generation), and comparison of SPFC with competing technologies. The economics of SPFC and conventional technologies for commercial applications are compared and market opportunities and potential barriers to commercialisation are identified.

  12. Trends for Methane Oxidation at Solid Oxide Fuel Cell Conditions

    DEFF Research Database (Denmark)

    Kleis, Jesper; Jones, Glenn; Abild-Pedersen, Frank

    2009-01-01

    First-principles calculations are used to predict a plausible reaction pathway for the methane oxidation reaction. In turn, this pathway is used to obtain trends in methane oxidation activity at solid oxide fuel cell (SOFC) anode materials. Reaction energetics and barriers for the elementary...... the Ni surfaces to other metals of interest. This allows the reactivity over the different metals to be understood in terms of two reactivity descriptors, namely, the carbon and oxygen adsorption energies. By combining a simple free-energy analysis with microkinetic modeling, activity landscapes of anode...

  13. Impedance Modeling of Solid Oxide Fuel Cell Cathodes

    DEFF Research Database (Denmark)

    Mortensen, Jakob Egeberg; Søgaard, Martin; Jacobsen, Torben

    2010-01-01

    A 1-dimensional impedance model for a solid oxide fuel cell cathode is formulated and applied to a cathode consisting of 50/50 wt% strontium doped lanthanum cobaltite and gadolinia doped ceria. A total of 42 impedance spectra were recorded in the temperature range: 555-852°C and in the oxygen...... partial pressure range 0.028-1.00 atm. The recorded impedance spectra were successfully analyzed using the developed impedance model in the investigated temperature and oxygen partial pressure range. It is also demonstrated that the model can be used to predict how impedance spectra evolve with different...

  14. Global radiative effects of solid fuel cookstove aerosol emissions

    Science.gov (United States)

    Huang, Yaoxian; Unger, Nadine; Storelvmo, Trude; Harper, Kandice; Zheng, Yiqi; Heyes, Chris

    2018-04-01

    We apply the NCAR CAM5-Chem global aerosol-climate model to quantify the net global radiative effects of black and organic carbon aerosols from global and Indian solid fuel cookstove emissions for the year 2010. Our assessment accounts for the direct radiative effects, changes to cloud albedo and lifetime (aerosol indirect effect, AIE), impacts on clouds via the vertical temperature profile (semi-direct effect, SDE) and changes in the surface albedo of snow and ice (surface albedo effect). In addition, we provide the first estimate of household solid fuel black carbon emission effects on ice clouds. Anthropogenic emissions are from the IIASA GAINS ECLIPSE V5a inventory. A global dataset of black carbon (BC) and organic aerosol (OA) measurements from surface sites and aerosol optical depth (AOD) from AERONET is used to evaluate the model skill. Compared with observations, the model successfully reproduces the spatial patterns of atmospheric BC and OA concentrations, and agrees with measurements to within a factor of 2. Globally, the simulated AOD agrees well with observations, with a normalized mean bias close to zero. However, the model tends to underestimate AOD over India and China by ˜ 19 ± 4 % but overestimate it over Africa by ˜ 25 ± 11 % (± represents modeled temporal standard deviations for n = 5 run years). Without BC serving as ice nuclei (IN), global and Indian solid fuel cookstove aerosol emissions have net global cooling radiative effects of -141 ± 4 mW m-2 and -12 ± 4 mW m-2, respectively (± represents modeled temporal standard deviations for n = 5 run years). The net radiative impacts are dominated by the AIE and SDE mechanisms, which originate from enhanced cloud condensation nuclei concentrations for the formation of liquid and mixed-phase clouds, and a suppression of convective transport of water vapor from the lower troposphere to the upper troposphere/lower stratosphere that in turn leads to reduced ice cloud formation. When BC is allowed

  15. Cooking with Fire: The Mutagenicity- and PAH-Emission Factors of Solid-Fuel Cookstoves

    Science.gov (United States)

    Emissions from solid fuels used for cooking cause ~4 million premature deaths per year. Advanced solid-fuel cookstoves are a potential solution, but they should be assessed by appropriate performance indicators, including biological effects. We evaluated two categories of solid...

  16. Rocket propulsion elements - An introduction to the engineering of rockets (6th revised and enlarged edition)

    Science.gov (United States)

    Sutton, George P.

    The subject of rocket propulsion is treated with emphasis on the basic technology, performance, and design rationale. Attention is given to definitions and fundamentals, nozzle theory and thermodynamic relations, heat transfer, flight performance, chemical rocket propellant performance analysis, and liquid propellant rocket engine fundamentals. The discussion also covers solid propellant rocket fundamentals, hybrid propellant rockets, thrust vector control, selection of rocket propulsion systems, electric propulsion, and rocket testing.

  17. Sampling, characterisation and processing of solid recovered fuel production from municipal solid waste: An Italian plant case study.

    Science.gov (United States)

    Ranieri, Ezio; Ionescu, Gabriela; Fedele, Arcangela; Palmieri, Eleonora; Ranieri, Ada Cristina; Campanaro, Vincenzo

    2017-08-01

    This article presents the classification of solid recovered fuel from the Massafra municipal solid waste treatment plant in Southern Italy in compliancy with the EN 15359 standard. In order to ensure the reproducibility of this study, the characterisation methods of waste input and output flow, the mechanical biological treatment line scheme and its main parameters for each stage of the processing chain are presented in details, together with the research results in terms of mass balance and derived fuel properties. Under this study, only 31% of refused municipal solid waste input stream from mechanical biological line was recovered as solid recovered fuel with a net heating value (NC=HV) average of 15.77 MJ kg -1 ; chlorine content average of 0.06% on a dry basis; median of mercury solid recovered fuel produced meets the European Union standard requirements and can be classified with the class code: Net heating value (3); chlorine (1); mercury (1).

  18. Development of Erosive Burning Models for CFD Predictions of Solid Rocket Motor Internal Environments

    Science.gov (United States)

    Wang, Qun-Zhen

    2003-01-01

    Four erosive burning models, equations (11) to (14). are developed in this work by using a power law relationship to correlate (1) the erosive burning ratio and the local velocity gradient at propellant surfaces; (2) the erosive burning ratio and the velocity gradient divided by centerline velocity; (3) the erosive burning difference and the local velocity gradient at propellant surfaces; and (4) the erosive burning difference and the velocity gradient divided by centerline velocity. These models depend on the local velocity gradient at the propellant surface (or the velocity gradient divided by centerline velocity) only and, unlike other empirical models, are independent of the motor size. It was argued that, since the erosive burning is a local phenomenon occurring near the surface of the solid propellant, the erosive burning ratio should be independent of the bore diameter if it is correlated with some local flow parameters such as the velocity gradient at the propellant surface. This seems to be true considering the good results obtained by applying these models, which are developed from the small size 5 inch CP tandem motor testing, to CFD simulations of much bigger motors.

  19. A solid oxide fuel cell system for buildings

    International Nuclear Information System (INIS)

    Zink, Florian; Lu, Yixin; Schaefer, Laura

    2007-01-01

    This paper examines an integrated solid oxide fuel cell (SOFC) absorption heating and cooling system used for buildings. The integrated system can provide heating/cooling and/or hot water for buildings while consuming natural gas. The aim of this study is to give an overall description of the system. The possibility of such an integrated system is discussed and the configuration of the system is described. A system model is presented, and a specific case study of the system, which consists of a pre-commercial SOFC system and a commercial LiBr absorption system, is performed. In the case study, the detailed configuration of an integrated system is given, and the heat and mass balance and system performance are obtained through numerical calculation. Based on the case study, some considerations with respect to system component selection, system configuration and design are discussed. Additionally, the economic and environmental issues of this specific system are evaluated briefly. The results show that the combined system demonstrates great advantages in both technical and environmental aspects. With the present development trends in solid oxide fuel cells and the commercial status of absorption heating and cooling systems, it is very likely that such a combined system will become increasingly feasible within the following decade

  20. Fuel efficient hydrodynamic containment for gas core fission reactor rocket propulsion. Final report, September 30, 1992--May 31, 1995

    International Nuclear Information System (INIS)

    Sforza, P.M.; Cresci, R.J.

    1997-01-01

    Gas core reactors can form the basis for advanced nuclear thermal propulsion (NTP) systems capable of providing specific impulse levels of more than 2,000 sec., but containment of the hot uranium plasma is a major problem. The initial phase of an experimental study of hydrodynamic confinement of the fuel cloud in a gas core fission reactor by means of an innovative application of a base injection stabilized recirculation bubble is presented. The development of the experimental facility, a simulated thrust chamber approximately 0.4 m in diameter and 1 m long, is described. The flow rate of propellant simulant (air) can be varied up to about 2 kg/sec and that of fuel simulant (air, air-sulfur hexafluoride) up to about 0.2 kg/sec. This scale leads to chamber Reynolds numbers on the same order of magnitude as those anticipated in a full-scale nuclear rocket engine. The experimental program introduced here is focused on determining the size, geometry, and stability of the recirculation region as a function of the bleed ratio, i.e. the ratio of the injected mass flux to the free stream mass flux. A concurrent CFD study is being carried out to aid in demonstrating that the proposed technique is practical

  1. Electrode Design for Low Temperature Direct-Hydrocarbon Solid Oxide Fuel Cells

    Science.gov (United States)

    Chen, Fanglin (Inventor); Zhao, Fei (Inventor); Liu, Qiang (Inventor)

    2015-01-01

    In certain embodiments of the present disclosure, a solid oxide fuel cell is described. The solid oxide fuel cell includes a hierarchically porous cathode support having an impregnated cobaltite cathode deposited thereon, an electrolyte, and an anode support. The anode support includes hydrocarbon oxidation catalyst deposited thereon, wherein the cathode support, electrolyte, and anode support are joined together and wherein the solid oxide fuel cell operates a temperature of 600.degree. C. or less.

  2. Electrode design for low temperature direct-hydrocarbon solid oxide fuel cells

    Science.gov (United States)

    Chen, Fanglin; Zhao, Fei; Liu, Qiang

    2015-10-06

    In certain embodiments of the present disclosure, a solid oxide fuel cell is described. The solid oxide fuel cell includes a hierarchically porous cathode support having an impregnated cobaltite cathode deposited thereon, an electrolyte, and an anode support. The anode support includes hydrocarbon oxidation catalyst deposited thereon, wherein the cathode support, electrolyte, and anode support are joined together and wherein the solid oxide fuel cell operates a temperature of 600.degree. C. or less.

  3. Criteria for solid recovered fuels as a substitute for fossil fuels--a review.

    Science.gov (United States)

    Beckmann, Michael; Pohl, Martin; Bernhardt, Daniel; Gebauer, Kathrin

    2012-04-01

    The waste treatment, particularly the thermal treatment of waste has changed fundamentally in the last 20 years, i.e. from facilities solely dedicated to the thermal treatment of waste to facilities, which in addition to that ensure the safe plant operation and fulfill very ambitious criteria regarding emission reduction, resource recovery and energy efficiency as well. Therefore this contributes to the economic use of raw materials and due to the energy recovered from waste also to the energy provision. The development described had the consequence that waste and solid recovered fuels (SRF) has to be evaluated based on fuel criteria as well. Fossil fuels - coal, crude oil, natural gas etc. have been extensively investigated due to their application in plants for energy conversion and also due to their use in the primary industry. Thereby depending on the respective processes, criteria on fuel technical properties can be derived. The methods for engineering analysis of regular fuels (fossil fuels) can be transferred only partially to SRF. For this reason methods are being developed or adapted to current analytical methods for the characterization of SRF. In this paper the possibilities of the energetic utilization of SRF and the characterization of SRF before and during the energetic utilization will be discussed.

  4. Solid oxide fuel cell having a monolithic core

    International Nuclear Information System (INIS)

    Ackerman, J.P.; Young, J.E.

    1984-01-01

    A solid oxide fuel cell for electrochemically combining fuel and oxidant for generating galvanic output, wherein the cell core has an array of electrolyte and interconnect walls that are substantially devoid of any composite inert materials for support. Instead, the core is monolithic, where each electrolyte wall consists of thin layers of cathode and anode materials sandwiching a thin layer of electrolyte material therebetween, and each interconnect wall consists of thin layers of the cathode and anode materials sandwiching a thin layer of interconnect material therebetween. The electrolyte walls are arranged and backfolded between adjacent interconnect walls operable to define a plurality of core passageways alternately arranged where the inside faces thereof have only the anode material or only the cathode material exposed. Means direct the fuel to the anode-exposed core passageways and means direct the oxidant to the cathode-exposed core passageway; and means also direct the galvanic output to an exterior circuit. Each layer of the electrolyte and interconnect materials is of the order of 0.002-0.01 cm thick; and each layer of the cathode and anode materials is of the order of 0.002-0.05 cm thick

  5. Ceramic membrane fuel cells based on solid proton electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Guangyao; Ma, Qianli; Peng, Ranran; Liu, Xingqin [USTC Lab. for Solid State Chemistry and Inorganic Membranes, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026 (China); Ma, Guilin [School of Chemistry and Chemical Engineering, Suzhou University, Suzhou 215123 (China)

    2007-04-15

    The development of solid oxide fuel cells (SOFCs) has reached its new stage characterized with thin electrolytes on porous electrode support, and the most important fabrication techniques developed in which almost all are concerned with inorganic membranes, and so can be named as ceramic membrane fuel cells (CMFCs). CMFCs based on proton electrolytes (CMFC-H) may exhibit more advantages than CMFCs based on oxygen-ion electrolytes (CMFC-O) in many respects, such as energy efficiency and avoiding carbon deposit. Ammonia fuelled CMFC with proton-conducting BaCe{sub 0.8}Gd{sub 0.2}O{sub 2.9} (BCGO) electrolyte (50 {mu}m in thickness) is reported in this works, which showed the open current voltage (OCV) values close to theoretical ones and rather high power density. And also, we have found that the well known super oxide ion conductor, La{sub 0.9}Sr{sub 0.1}Ga{sub 0.8}Mg{sub 0.2}O{sub 3-{alpha}} (LSGM), is a pure proton conductor in H{sub 2} and mixed proton and oxide ion conductor in wet air, while it is a pure oxide ion conductor in oxygen or dry air. To demonstrate the CMFC-H concept to get high performance fuel cells the techniques for thin membranes, chemical vapor deposition (CVD), particularly novel CVD techniques, should be given more attention because of their many advantages. (author)

  6. Superheated fuel injection for combustion of liquid-solid slurries

    Science.gov (United States)

    Robben, F.A.

    1984-10-19

    A method and device are claimed for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel is heated under pressure to near critical temperature in an injector accumulator, where the pressure is sufficiently high to prevent boiling. After injection into a combustion chamber, the water temperature will be well above boiling point at a reduced pressure in the combustion chamber, and flash boiling will preferentially take place at solid-liquid surfaces, resulting in the shattering of water droplets and the subsequent separation of the water from coal particles. This prevents the agglomeration of the coal particles during the subsequent ignition and combustion process, and reduces the energy required to evaporate the water and to heat the coal particles to ignition temperature. The overall effect will be to accelerate the ignition and combustion rates, and to reduce the size of the ash particles formed from the coal. 2 figs., 2 tabs.

  7. Tecnored process - high potential in using different kinds of solid fuels

    Directory of Open Access Journals (Sweden)

    José Henrique Noldin Júnior

    2005-12-01

    Full Text Available One important feature of the Brazilian Tecnored ironmaking process is its flexibility to use different types of solid fuels, other than metallurgical coke, as proved in the pilot plant tests by extensively using green petroleum coke, biomasses, high ash cokes, etc. Even if new solid fuels not thus far used are envisaged for a given project, thru the bench scale simulator of the process it is possible to predict the behavior of such solid fuels in the Tecnored furnace and establish the best techno-economical-environmental equation for its use. This paper discusses the key aspects involved in the use of alternative solid fuels in the Tecnored process.

  8. On the intrinsic transient capability and limitations of solid oxide fuel cell systems

    OpenAIRE

    Mueller, F; Jabbari, F; Brouwer, J

    2009-01-01

    The intrinsic transient performance capability and limitation of integrated solid oxide fuel cell (SOFC) systems is evaluated based on the system balance-of-plant response and fuel cell operating requirements (i.e., allowable deviation from nominal operation). Specifically, non-dimensional relations are derived from conservation principles that quantify the maximum instantaneous current increase that a solid oxide fuel cell system can safely manage based on (1) the desired fuel cell operating...

  9. Evaluation of apatite silicates as solid oxide fuel cell electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Marrero-Lopez, D. [Dpto. de Fisica Aplicada I, Laboratorio de Materiales y Superficies (Unidad Asociada al C.S.I.C.), Universidad de Malaga, 29071 Malaga (Spain); Dpto. de Quimica Inorganica, Universidad de La Laguna, 38200 La Laguna, Tenerife (Spain); Martin-Sedeno, M.C.; Aranda, M.A.G. [Dpto. de Quimica Inorganica, Universidad Malaga, 29071 Malaga (Spain); Pena-Martinez, J. [Dpto. de Quimica Inorganica, Universidad de La Laguna, 38200 La Laguna, Tenerife (Spain); Instituto de Energias Renovables, Parque Tecnologico, Universidad de Castilla La Mancha, 02006 Albacete (Spain); Ruiz-Morales, J.C.; Nunez, P. [Dpto. de Quimica Inorganica, Universidad de La Laguna, 38200 La Laguna, Tenerife (Spain); Ramos-Barrado, J.R. [Dpto. de Fisica Aplicada I, Laboratorio de Materiales y Superficies (Unidad Asociada al C.S.I.C.), Universidad de Malaga, 29071 Malaga (Spain)

    2010-05-01

    Apatite-type silicates have been considered as promising electrolytes for Solid Oxide Fuel Cells (SOFC); however studies on the potential use of these materials in SOFC devices have received relatively little attention. The lanthanum silicate with composition La{sub 10}Si{sub 5.5}Al{sub 0.5}O{sub 26.75} has been evaluated as electrolyte with the electrode materials commonly used in SOFC, i.e. manganite, ferrite and cobaltite as cathode materials and NiO-CGO composite, chromium-manganite and Sr{sub 2}MgMoO{sub 6} as anode materials. Chemical compatibility, area-specific resistance and fuel cell studies have been performed. X-ray powder diffraction (XRPD) analysis did not reveal any trace of reaction products between the apatite electrolyte and most of the aforementioned electrode materials. However, the area-specific polarisation resistance (ASR) of these electrodes in contact with apatite electrolyte increased significantly with the sintering temperature, indicating reactivity at the electrolyte/electrode interface. On the other hand, the ASR values are significantly improved using a ceria buffer layer between the electrolyte and electrode materials to prevent reactivity. Maximum power densities of 195 and 65 mWcm{sup -2} were obtained at 850 and 700 C, respectively in H{sub 2} fuel, using an 1 mm-thick electrolyte, a NiO-Ce{sub 0.8}Gd{sub 0.2}O{sub 1.9} composite as anode and La{sub 0.6}Sr{sub 0.4}Co{sub 0.8}Fe{sub 0.2}O{sub 3-{delta}} as cathode materials. This fuel cell was tested for 100 h in 5%H{sub 2}-Ar atmosphere showing stable performance. (author)

  10. System Sensitivity Analysis Applied to the Conceptual Design of a Dual-Fuel Rocket SSTO

    Science.gov (United States)

    Olds, John R.

    1994-01-01

    This paper reports the results of initial efforts to apply the System Sensitivity Analysis (SSA) optimization method to the conceptual design of a single-stage-to-orbit (SSTO) launch vehicle. SSA is an efficient, calculus-based MDO technique for generating sensitivity derivatives in a highly multidisciplinary design environment. The method has been successfully applied to conceptual aircraft design and has been proven to have advantages over traditional direct optimization methods. The method is applied to the optimization of an advanced, piloted SSTO design similar to vehicles currently being analyzed by NASA as possible replacements for the Space Shuttle. Powered by a derivative of the Russian RD-701 rocket engine, the vehicle employs a combination of hydrocarbon, hydrogen, and oxygen propellants. Three primary disciplines are included in the design - propulsion, performance, and weights & sizing. A complete, converged vehicle analysis depends on the use of three standalone conceptual analysis computer codes. Efforts to minimize vehicle dry (empty) weight are reported in this paper. The problem consists of six system-level design variables and one system-level constraint. Using SSA in a 'manual' fashion to generate gradient information, six system-level iterations were performed from each of two different starting points. The results showed a good pattern of convergence for both starting points. A discussion of the advantages and disadvantages of the method, possible areas of improvement, and future work is included.

  11. The sky is falling III: The effect of deposition from static solid rocket motor tests on juvenile crops.

    Science.gov (United States)

    Doucette, William J; Curry, Eric; McNeill, Laurie S; Heavilin, Justin

    2017-12-01

    A mixture of combustion products (mainly hydrogen chloride, aluminum oxide, and water) and entrained soil, referred to as Test Fire Soil (TFS), can be deposited on crops during static solid rocket motor tests. The impact of a reported worst-case event was previously evaluated by exposing corn and alfalfa to 3200-gTFS/m 2 at 54days after emergence. Exposures via soil and leaves were evaluated separately. Reduced growth (soil exposure) and leaf "scorch" (leaf exposure) were attributed mainly to the high chloride concentrations in the TFS (56,000mg/kg). A follow-up study was conducted to evaluate the effect of a typical deposition event (70-gTFS/m 2 , estimated by radar during several tests) and exposure (soil and leaves simultaneously) on juvenile corn, alfalfa, and winter wheat. Younger crops were used to examine potential age sensitivity differences. Impact was evaluated by comparing the growth, elemental composition, and leaf chlorophyll content of treated and untreated plants. The relationship between deposition exposure and response was also addressed. Growth of corn, alfalfa, and winter wheat exposed to a typical TFS loading was not impacted, although slightly elevated concentrations of aluminum and iron were found in the leaves. At the highest loadings used for the exposure-response experiment, concentrations of chloride and calcium were higher in TFS-exposed corn leaves than in the untreated leaves. Overall results indicate that exposure to a typical deposition event does not adversely impact juvenile crops and that younger plants may be less vulnerable to TFS. However, higher TFS loadings can cause leaf scorch and increase the leaf concentrations of some elements. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. NEW SOLID FUELS FROM COAL AND BIOMASS WASTE; FINAL

    International Nuclear Information System (INIS)

    Hamid Farzan

    2001-01-01

    fuel. These fuels will be converted to energy while reducing CO(sub 2) emissions from power generating boilers and mitigating global warming concerns. This report describes the sludge analysis, solid fuel preparation and production, combustion performance, environmental emissions and required equipment

  13. Solid oxide fuel cell bi-layer anode with gadolinia-doped ceria for utilization of solid carbon fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kellogg, Isaiah D. [Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, 290A Toomey Hall, 400 West 13th Street, Rolla, MO 65409 (United States); Department of Materials Science and Engineering, Missouri University of Science and Technology, 223 McNutt Hall, 1400 N. Bishop, Rolla, MO 65409 (United States); Koylu, Umit O. [Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, 290A Toomey Hall, 400 West 13th Street, Rolla, MO 65409 (United States); Dogan, Fatih [Department of Materials Science and Engineering, Missouri University of Science and Technology, 223 McNutt Hall, 1400 N. Bishop, Rolla, MO 65409 (United States)

    2010-11-01

    Pyrolytic carbon was used as fuel in a solid oxide fuel cell (SOFC) with a yttria-stabilized zirconia (YSZ) electrolyte and a bi-layer anode composed of nickel oxide gadolinia-doped ceria (NiO-GDC) and NiO-YSZ. The common problems of bulk shrinkage and emergent porosity in the YSZ layer adjacent to the GDC/YSZ interface were avoided by using an interlayer of porous NiO-YSZ as a buffer anode layer between the electrolyte and the NiO-GDC primary anode. Cells were fabricated from commercially available component powders so that unconventional production methods suggested in the literature were avoided, that is, the necessity of glycine-nitrate combustion synthesis, specialty multicomponent oxide powders, sputtering, or chemical vapor deposition. The easily-fabricated cell was successfully utilized with hydrogen and propane fuels as well as carbon deposited on the anode during the cyclic operation with the propane. A cell of similar construction could be used in the exhaust stream of a diesel engine to capture and utilize soot for secondary power generation and decreased particulate pollution without the need for filter regeneration. (author)

  14. Processing and properties of a solid energy fuel from municipal solid waste (MSW) and recycled plastics.

    Science.gov (United States)

    Gug, JeongIn; Cacciola, David; Sobkowicz, Margaret J

    2015-01-01

    Diversion of waste streams such as plastics, woods, papers and other solid trash from municipal landfills and extraction of useful materials from landfills is an area of increasing interest especially in densely populated areas. One promising technology for recycling municipal solid waste (MSW) is to burn the high-energy-content components in standard coal power plant. This research aims to reform wastes into briquettes that are compatible with typical coal combustion processes. In order to comply with the standards of coal-fired power plants, the feedstock must be mechanically robust, free of hazardous contaminants, and moisture resistant, while retaining high fuel value. This study aims to investigate the effects of processing conditions and added recyclable plastics on the properties of MSW solid fuels. A well-sorted waste stream high in paper and fiber content was combined with controlled levels of recyclable plastics PE, PP, PET and PS and formed into briquettes using a compression molding technique. The effect of added plastics and moisture content on binding attraction and energy efficiency were investigated. The stability of the briquettes to moisture exposure, the fuel composition by proximate analysis, briquette mechanical strength, and burning efficiency were evaluated. It was found that high processing temperature ensures better properties of the product addition of milled mixed plastic waste leads to better encapsulation as well as to greater calorific value. Also some moisture removal (but not complete) improves the compacting process and results in higher heating value. Analysis of the post-processing water uptake and compressive strength showed a correlation between density and stability to both mechanical stress and humid environment. Proximate analysis indicated heating values comparable to coal. The results showed that mechanical and moisture uptake stability were improved when the moisture and air contents were optimized. Moreover, the briquette

  15. Structural analysis of nickel doped cerium oxide catalysts for fuel reforming in solid oxide fuel cells

    Science.gov (United States)

    Cavendish, Rio

    As world energy demands increase, research into more efficient energy production methods has become imperative. Heterogeneous catalysis and nanoscience are used to promote chemical transformations important for energy production. These concepts are important in solid oxide fuel cells (SOFCs) which have attracted attention because of their potential to provide an efficient and environmentally favorable power generation system. The SOFC is also fuel-flexible with the ability to run directly on many fuels other than hydrogen. Internal fuel reforming directly in the anode of the SOFC would greatly reduce the cost and complexity of the device. Methane is the simplest hydrocarbon and a main component in natural gas, making it useful when testing catalysts on the laboratory scale. Nickel (Ni) and gadolinium (Gd) doped ceria (CeO 2) catalysts for potential use in the SOFC anode were synthesized with a spray drying method and tested for catalytic performance using partial oxidation of methane and steam reforming. The relationships between catalytic performance and structure were then investigated using X-ray diffraction, transmission electron microscopy, and environmental transmission electron microscopy. The possibility of solid solutions, segregated phases, and surface layers of Ni were explored. Results for a 10 at.% Ni in CeO2 catalyst reveal a poor catalytic behavior while a 20 at.% Ni in CeO2 catalyst is shown to have superior activity. The inclusion of both 10 at.% Gd and 10 at.% Ni in CeO2 enhances the catalytic performance. Analysis of the presence of Ni in all 3 samples reveals Ni heterogeneity and little evidence for extensive solid solution doping. Ni is found in small domains throughout CeO2 particles. In the 20 at.% Ni sample a segregated, catalytically active NiO phase is observed. Overall, it is found that significant interaction between Ni and CeO2 occurs that could affect the synthesis and functionality of the SOFC anode.

  16. Mixed fuel strategy for carbon deposition mitigation in solid oxide fuel cells at intermediate temperatures.

    Science.gov (United States)

    Su, Chao; Chen, Yubo; Wang, Wei; Ran, Ran; Shao, Zongping; Diniz da Costa, João C; Liu, Shaomin

    2014-06-17

    In this study, we propose and experimentally verified that methane and formic acid mixed fuel can be employed to sustain solid oxide fuel cells (SOFCs) to deliver high power outputs at intermediate temperatures and simultaneously reduce the coke formation over the anode catalyst. In this SOFC system, methane itself was one part of the fuel, but it also played as the carrier gas to deliver the formic acid to reach the anode chamber. On the other hand, the products from the thermal decomposition of formic acid helped to reduce the carbon deposition from methane cracking. In order to clarify the reaction pathways for carbon formation and elimination occurring in the anode chamber during the SOFC operation, O2-TPO and SEM analysis were carried out together with the theoretical calculation. Electrochemical tests demonstrated that stable and high power output at an intermediate temperature range was well-maintained with a peak power density of 1061 mW cm(-2) at 750 °C. With the synergic functions provided by the mixed fuel, the SOFC was running for 3 days without any sign of cell performance decay. In sharp contrast, fuelled by pure methane and tested at similar conditions, the SOFC immediately failed after running for only 30 min due to significant carbon deposition. This work opens a new way for SOFC to conquer the annoying problem of carbon deposition just by properly selecting the fuel components to realize their synergic effects.

  17. Rocket Fuel R and D at AFRL: Recent Activities and Future Direction

    Science.gov (United States)

    2017-04-12

    ethanol RP-1 Polars Analysis JFTOT (5 hr., 355°C) Fuel Phenolsmg/L (ppm) Aliphatic ketones mg/L (ppm) Max ΔTDR (Spun) Max ΔP (mmHg) 12366 160 (200) 19...Lubricity & Wear Turbopump and Bearing 3D white light depth of HFRR ball end Ref A RP-1 23DISTRIBUTION A: Approved for Public Release; Distribution

  18. Processing and properties of a solid energy fuel from municipal solid waste (MSW) and recycled plastics

    International Nuclear Information System (INIS)

    Gug, JeongIn; Cacciola, David; Sobkowicz, Margaret J.

    2015-01-01

    Highlights: • Briquetting was used to produce solid fuels from municipal solid waste and recycled plastics. • Optimal drying, processing temperature and pressure were found to produce stable briquettes. • Addition of waste plastics yielded heating values comparable with typical coal feedstocks. • This processing method improves utilization of paper and plastic diverted from landfills. - Abstract: Diversion of waste streams such as plastics, woods, papers and other solid trash from municipal landfills and extraction of useful materials from landfills is an area of increasing interest especially in densely populated areas. One promising technology for recycling municipal solid waste (MSW) is to burn the high-energy-content components in standard coal power plant. This research aims to reform wastes into briquettes that are compatible with typical coal combustion processes. In order to comply with the standards of coal-fired power plants, the feedstock must be mechanically robust, free of hazardous contaminants, and moisture resistant, while retaining high fuel value. This study aims to investigate the effects of processing conditions and added recyclable plastics on the properties of MSW solid fuels. A well-sorted waste stream high in paper and fiber content was combined with controlled levels of recyclable plastics PE, PP, PET and PS and formed into briquettes using a compression molding technique. The effect of added plastics and moisture content on binding attraction and energy efficiency were investigated. The stability of the briquettes to moisture exposure, the fuel composition by proximate analysis, briquette mechanical strength, and burning efficiency were evaluated. It was found that high processing temperature ensures better properties of the product addition of milled mixed plastic waste leads to better encapsulation as well as to greater calorific value. Also some moisture removal (but not complete) improves the compacting process and results in

  19. Processing and properties of a solid energy fuel from municipal solid waste (MSW) and recycled plastics

    Energy Technology Data Exchange (ETDEWEB)

    Gug, JeongIn, E-mail: Jeongin_gug@student.uml.edu; Cacciola, David, E-mail: david_cacciola@student.uml.edu; Sobkowicz, Margaret J., E-mail: Margaret_sobkowiczkline@uml.edu

    2015-01-15

    Highlights: • Briquetting was used to produce solid fuels from municipal solid waste and recycled plastics. • Optimal drying, processing temperature and pressure were found to produce stable briquettes. • Addition of waste plastics yielded heating values comparable with typical coal feedstocks. • This processing method improves utilization of paper and plastic diverted from landfills. - Abstract: Diversion of waste streams such as plastics, woods, papers and other solid trash from municipal landfills and extraction of useful materials from landfills is an area of increasing interest especially in densely populated areas. One promising technology for recycling municipal solid waste (MSW) is to burn the high-energy-content components in standard coal power plant. This research aims to reform wastes into briquettes that are compatible with typical coal combustion processes. In order to comply with the standards of coal-fired power plants, the feedstock must be mechanically robust, free of hazardous contaminants, and moisture resistant, while retaining high fuel value. This study aims to investigate the effects of processing conditions and added recyclable plastics on the properties of MSW solid fuels. A well-sorted waste stream high in paper and fiber content was combined with controlled levels of recyclable plastics PE, PP, PET and PS and formed into briquettes using a compression molding technique. The effect of added plastics and moisture content on binding attraction and energy efficiency were investigated. The stability of the briquettes to moisture exposure, the fuel composition by proximate analysis, briquette mechanical strength, and burning efficiency were evaluated. It was found that high processing temperature ensures better properties of the product addition of milled mixed plastic waste leads to better encapsulation as well as to greater calorific value. Also some moisture removal (but not complete) improves the compacting process and results in

  20. Multi-metallic anodes for solid oxide fuel cell applications

    International Nuclear Information System (INIS)

    Restivo, T.A. Guisard; Mello-Castanho, S.R.H.; Leite, D. Will

    2009-01-01

    A new method for direct preparation of materials for solid oxide fuel cell anode - Ni- YSZ cermets - based on mechanical alloying (MA) of the original powders is developed, allowing to admix homogeneously any component. Additive metals are selected from thermodynamic criteria, leading to compacts consolidation through sintering by activated surface (SAS). The combined process MA-SSA can reduce the sintering temperature by 300 deg C, yielding porous anodes. Densification mechanisms are discussed from quasi-isothermal sintering kinetics results. Doping with Ag, W, Cu, Mo, Nb, Ta, in descending order, promotes the densification of pellets through liquid phase sintering and evaporation of metals and oxides, which allow reducing the sintering temperature. Powders and pellets characterization by electronic microscopy and X-ray diffraction completes the result analyses. (author)

  1. Cathodes for Solid Oxide Fuel Cells Operating at Low Temperatures

    DEFF Research Database (Denmark)

    Samson, Alfred Junio

    . High performance cathodes were obtained from strontium-doped lanthanum cobaltite (LSC) infiltrated - Ce0.9Gd0.1O1.95 (CGO) ionic conducting backbone. Systematic tuning of the CGO and LSC firing temperatures and LSC loading resulted in a cathode with low polarization resistance, Rp = 0.044 cm2 at 600......This dissertation focuses on the development of nanostructured cathodes for solid oxide fuel cells (SOFCs) and their performance at low operating temperatures. Cathodes were mainly fabricated by the infiltration method, whereby electrocatalysts are introduced onto porous, ionic conducting backbones...... with increasing LSC firing temperature, highlighting the importance of materials compability over higher ionic conductivity. The potential of Ca3Co4O9+delta as an electrocatalyst for SOFCs has also been explored and encouraging results were found i.e., Rp = 0.64 cm2 for a Ca3Co4O9+delta/CGO 50 vol % composite...

  2. Failure analysis of electrolyte-supported solid oxide fuel cells

    Science.gov (United States)

    Fleischhauer, Felix; Tiefenauer, Andreas; Graule, Thomas; Danzer, Robert; Mai, Andreas; Kuebler, Jakob

    2014-07-01

    For solid oxide fuel cells (SOFCs) one key aspect is the structural integrity of the cell and hence its thermo mechanical long term behaviour. The present study investigates the failure mechanisms and the actual causes for fracture of electrolyte supported SOFCs which were run using the current μ-CHP system of Hexis AG, Winterthur - Switzerland under lab conditions or at customer sites for up to 40,000 h. In a first step several operated stacks were demounted for post-mortem inspection, followed by a fractographic evaluation of the failed cells. The respective findings are then set into a larger picture including an analysis of the present stresses acting on the cell like thermal and residual stresses and the measurements regarding the temperature dependent electrolyte strength. For all investigated stacks, the mechanical failure of individual cells can be attributed to locally acting bending loads, which rise due to an inhomogeneous and uneven contact between the metallic interconnect and the cell.

  3. Anodes for Solid Oxide Fuel Cells Operating at Low Temperatures

    DEFF Research Database (Denmark)

    Abdul Jabbar, Mohammed Hussain

    An important issue that has limited the potential of Solid Oxide Fuel Cells (SOFCs) for portable applications is its high operating temperatures (800-1000 ºC). Lowering the operating temperature of SOFCs to 400-600 ºC enable a wider material selection, reduced degradation and increased lifetime....... On the other hand, low-temperature operation poses serious challenges to the electrode performance. Effective catalysts, redox stable electrodes with improved microstructures are the prime requisite for the development of efficient SOFC anodes. The performance of Nb-doped SrT iO3 (STN) ceramic anodes...... at 400ºC. The potential of using WO3 ceramic as an alternative anode materials has been explored. The relatively high electrode polarization resistance obtained, 11 Ohm cm2 at 600 ºC, proved the inadequate catalytic activity of this system for hydrogen oxidation. At the end of this thesis...

  4. Solid oxide fuel cell having a glass composite seal

    Science.gov (United States)

    De Rose, Anthony J.; Mukerjee, Subhasish; Haltiner, Jr., Karl Jacob

    2013-04-16

    A solid oxide fuel cell stack having a plurality of cassettes and a glass composite seal disposed between the sealing surfaces of adjacent cassettes, thereby joining the cassettes and providing a hermetic seal therebetween. The glass composite seal includes an alkaline earth aluminosilicate (AEAS) glass disposed about a viscous glass such that the AEAS glass retains the viscous glass in a predetermined position between the first and second sealing surfaces. The AEAS glass provides geometric stability to the glass composite seal to maintain the proper distance between the adjacent cassettes while the viscous glass provides for a compliant and self-healing seal. The glass composite seal may include fibers, powders, and/or beads of zirconium oxide, aluminum oxide, yttria-stabilized zirconia (YSZ), or mixtures thereof, to enhance the desirable properties of the glass composite seal.

  5. Trade of Solid Biofuels, and Fuel Prices in Europe

    International Nuclear Information System (INIS)

    Alakangas, E.; Hillring, B.; Nikolaisen, L.S.

    2002-01-01

    Traditionally, biomass fuels are used in the same geographical region, in which they are produced. In more recent years, this pattern has been changed in Northern Europe by large-scale use of biomass for district heating and a vast supply of recycled wood and forest residues. The trade situation has come about as a result of means of control on waste and energy. Sea shipments allow bulk transports of biomass over long distances at low cost. In most countries, the customs statistics do not record trade in such a detail that the international trade of different biomass types could be identified. Today, solid biofuels like wood residues, pellets and wood chips are already traded in Europe and have reached a level of almost 50 PJ/a. In some countries, there is a growing interest in the international biomass trade, because the trade can provide biofuels at lower prices. The largest volumes of biomass are traded from the Baltic countries (Estonia, Latvia, Lithuania) to the Nordic countries (especially Sweden and Denmark, but also Finland). Some volumes are also traded from Finland to other Nordic countries, and between neighbouring countries in Central Europe, especially the Netherlands, Germany, Austria, Slovenia and Italy. The traded biofuel is most often of refined wood fuels (pellets and briquettes) and industrial by-products (sawdust, chips), in Central Europe also wood waste

  6. Trade of Solid Biofuels, and Fuel Prices in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Alakangas, E. [VTT Processes, Jyvaeskylae (Finland); Hillring, B. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden); Nikolaisen, L.S. [Danish Technological Inst. (DTI), Aarhus (Denmark). Centre for Biomass Technology

    2002-07-01

    Traditionally, biomass fuels are used in the same geographical region, in which they are produced. In more recent years, this pattern has been changed in Northern Europe by large-scale use of biomass for district heating and a vast supply of recycled wood and forest residues. The trade situation has come about as a result of means of control on waste and energy. Sea shipments allow bulk transports of biomass over long distances at low cost. In most countries, the customs statistics do not record trade in such a detail that the international trade of different biomass types could be identified. Today, solid biofuels like wood residues, pellets and wood chips are already traded in Europe and have reached a level of almost 50 PJ/a. In some countries, there is a growing interest in the international biomass trade, because the trade can provide biofuels at lower prices. The largest volumes of biomass are traded from the Baltic countries (Estonia, Latvia, Lithuania) to the Nordic countries (especially Sweden and Denmark, but also Finland). Some volumes are also traded from Finland to other Nordic countries, and between neighbouring countries in Central Europe, especially the Netherlands, Germany, Austria, Slovenia and Italy. The traded biofuel is most often of refined wood fuels (pellets and briquettes) and industrial by-products (sawdust, chips), in Central Europe also wood waste.

  7. Integrated Solid Oxide Fuel Cell Power System Characteristics Prediction

    Directory of Open Access Journals (Sweden)

    Marian GAICEANU

    2009-07-01

    Full Text Available The main objective of this paper is to deduce the specific characteristics of the CHP 100kWe Solid Oxide Fuel Cell (SOFC Power System from the steady state experimental data. From the experimental data, the authors have been developed and validated the steady state mathematical model. From the control room the steady state experimental data of the SOFC power conditioning are available and using the developed steady state mathematical model, the authors have been obtained the characteristic curves of the system performed by Siemens-Westinghouse Power Corporation. As a methodology the backward and forward power flow analysis has been employed. The backward power flow makes possible to obtain the SOFC power system operating point at different load levels, resulting as the load characteristic. By knowing the fuel cell output characteristic, the forward power flow analysis is used to predict the power system efficiency in different operating points, to choose the adequate control decision in order to obtain the high efficiency operation of the SOFC power system at different load levels. The CHP 100kWe power system is located at Gas Turbine Technologies Company (a Siemens Subsidiary, TurboCare brand in Turin, Italy. The work was carried out through the Energia da Ossidi Solidi (EOS Project. The SOFC stack delivers constant power permanently in order to supply the electric and thermal power both to the TurboCare Company and to the national grid.

  8. Performance Analysis and Development Strategies for Solid Oxide Fuel Cells

    International Nuclear Information System (INIS)

    Ivers-Tiffee, E; Leonide, A; Weber, A

    2011-01-01

    Solid oxide fuel cells (SOFC) are of great interest for a diverse range of applications. Within the past 10 years, an increase in power density by one order of magnitude, a lowering of the operating temperature by 200 K, and degradation rates lowered by a factor of 10 have been achieved on the cell and stack level. However, there is still room for further enhancement of the overall performance by suitably tailoring the cell components on a micro- and nanostructural level. The efficiency of the electrochemically active single cell is characterized by the linear ohmic losses within the electrolyte and by nonlinear polarization losses at the electrode-electrolyte interfaces. Both depend on material composition and operation conditions (temperature and time, fuel utilisation and gas composition). The area-specific resistance (ASR) is considered as the figure of merit for overall performance. ASR values of anode supported cells (ASC) were determined by means of impedance spectroscopy and subsequently separated into ohmic losses (mainly electrolyte) and nonlinear polarisation losses resulting from gas diffusion and activation polarization in the cathode and anode. The efficiencies of ASCs will be discussed for various material combinations in the temperature range of technological interest (between 550 deg. C and 850 deg. C).

  9. Investigation of aluminosilicate refractory for solid oxide fuel cell applications

    Science.gov (United States)

    Gentile, Paul Steven

    Stationary solid oxide fuel cells (SOFCs) have been demonstrated to provide clean and reliable electricity through electro-chemical conversion of various fuel sources (CH4 and other light hydrocarbons). To become a competitive conversion technology the costs of SOFCs must be reduced to less than $400/kW. Aluminosilicate represents a potential low cost alternative to high purity alumina for SOFC refractory applications. The objectives of this investigation are to: (1) study changes of aluminosilicate chemistry and morphology under SOFC conditions, (2) identify volatile silicon species released by aluminosilicates, (3) identify the mechanisms of aluminosilicate vapor deposition on SOFC materials, and (4) determine the effects of aluminosilicate vapors on SOFC electrochemical performance. It is shown thermodynamically and empirically that low cost aluminosilicate refractory remains chemically and thermally unstable under SOFC operating conditions between 800°C and 1000°C. Energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) of the aluminosilicate bulk and surface identified increased concentrations of silicon at the surface after exposure to SOFC gases at 1000°C for 100 hours. The presence of water vapor accelerated surface diffusion of silicon, creating a more uniform distribution. Thermodynamic equilibrium modeling showed aluminosilicate remains stable in dry air, but the introduction of water vapor indicative of actual SOFC gas streams creates low temperature (active anode interface.

  10. Glass/Ceramic Composites for Sealing Solid Oxide Fuel Cells

    Science.gov (United States)

    Bansal, Narottam P.; Choi, Sung R.

    2007-01-01

    A family of glass/ceramic composite materials has been investigated for use as sealants in planar solid oxide fuel cells. These materials are modified versions of a barium calcium aluminosilicate glass developed previously for the same purpose. The composition of the glass in mole percentages is 35BaO + 15CaO + 5Al2O3 + 10B2O3 + 35SiO2. The glass seal was found to be susceptible to cracking during thermal cycling of the fuel cells. The goal in formulating the glass/ ceramic composite materials was to (1) retain the physical and chemical advantages that led to the prior selection of the barium calcium aluminosilicate glass as the sealant while (2) increasing strength and fracture toughness so as to reduce the tendency toward cracking. Each of the composite formulations consists of the glass plus either of two ceramic reinforcements in a proportion between 0 and 30 mole percent. One of the ceramic reinforcements consists of alumina platelets; the other one consists of particles of yttria-stabilized zirconia wherein the yttria content is 3 mole percent (3YSZ). In preparation for experiments, panels of the glass/ceramic composites were hot-pressed and machined into test bars.

  11. Solid oxide fuel cell performance under severe operating conditions

    DEFF Research Database (Denmark)

    Koch, Søren; Hendriksen, P.V.; Mogensen, Mogens Bjerg

    2006-01-01

    The performance and degradation of Solid Oxide Fuel Cells (SOFC) were studied under severe operating conditions. The cells studied were manufactured in a small series by ECN, in the framework of the EU funded CORE-SOFC project. The cells were of the anode-supported type with a double layer LSM...... cathode. They were operated at 750 °C or 850 °C in hydrogen with 5% or 50% water at current densities ranging from 0.25 A cm–2 to 1 A cm–2 for periods of 300 hours or more. The area specific cell resistance, corrected for fuel utilisation, ranged between 0.20 Ω cm2 and 0.34 Ω cm2 at 850 °C and 520 m......V, and between 0.51 Ω cm2 and 0.92 Ω cm2 at 750 °C and 520 mV. The degradation of cell performance was found to be low (ranging from 0 to 8%/1,000 hours) at regular operating conditions. Voltage degradation rates of 20 to 40%/1,000 hours were observed under severe operating conditions, depending on the test...

  12. Behavior of solid fission products in irradiated fuel

    International Nuclear Information System (INIS)

    Song, Ung Sup; Jung, Yang Hong; Kim, Hee Moon; Yoo, Byun Gok; Kim, Do Sik; Choo, Yong Sun; Hong, Kwon Pyo

    2004-01-01

    Many fission products are generated by fission events in UO 2 fuel under irradiation in nuclear reactor. Concentration of each fission product is changed by conditions of neutron energy spectrum, fissile material, critical thermal power, irradiation period and cooling time. Volatile materials such as Cs and I, the fission products, degrade nuclear fuel rod by the decrease of thermal conductivity in pellet and the stress corrosion cracking in cladding. Metal fission products (white inclusion) make pellet be swelled and decrease volume of pellet by densification. It seems that metal fission products are filled in the pore in pellet and placed between UO 2 lattices as interstitial. In addition, metal oxide state may change structural lattice volume. Considering behavior of fission products mentioned above, concentration of them is important. Fission products could be classified as bellows; solid solution in matrix : Sr, Zr, Nb, Y, La, Ce, Pr, Nd, Pm, Sm - metal precipitates : Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sb, Te - oxide precipitates : Ba, Zr, Nb, Mo, (Rb, Cs, Te) - volatile and gases : Kr, Xe, Br, I, (Rb, Cs, Te)

  13. Challenge for lowering concentration polarization in solid oxide fuel cells

    Science.gov (United States)

    Shimada, Hiroyuki; Suzuki, Toshio; Yamaguchi, Toshiaki; Sumi, Hirofumi; Hamamoto, Koichi; Fujishiro, Yoshinobu

    2016-01-01

    In the scope of electrochemical phenomena, concentration polarization at electrodes is theoretically inevitable, and lowering the concentration overpotential to improve the performance of electrochemical cells has been a continuing challenge. Electrodes with highly controlled microstructure, i.e., high porosity and uniform large pores are therefore essential to achieve high performance electrochemical cells. In this study, state-of-the-art technology for controlling the microstructure of electrodes has been developed for realizing high performance support electrodes of solid oxide fuel cells (SOFCs). The key is controlling the porosity and pore size distribution to improve gas diffusion, while maintaining the integrity of the electrolyte and the structural strength of actual sized electrode supports needed for the target application. Planar anode-supported SOFCs developed in this study realize 5 μm thick dense electrolyte (yttria-stabilized zirconia: YSZ) and the anode substrate (Ni-YSZ) of 53.6 vol.% porosity with a large median pore diameter of 0.911 μm. Electrochemical measurements reveal that the performance of the anode-supported SOFCs improves with increasing anode porosity. This Ni-YSZ anode minimizes the concentration polarization, resulting in a maximum power density of 3.09 W cm-2 at 800 °C using humidified hydrogen fuel without any electrode functional layers.

  14. Solid oxide fuel cells with bi-layered electrolyte structure

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xinge; Robertson, Mark; Deces-Petit, Cyrille; Xie, Yongsong; Hui, Rob; Qu, Wei; Kesler, Olivera; Maric, Radenka; Ghosh, Dave [Institute for Fuel Cell Innovation, National Research Council Canada, 4250 Wesbrook Mall, Vancouver, B.C. V6T 1W5 (Canada)

    2008-01-10

    In this work, we have developed solid oxide fuel cells with a bi-layered electrolyte of 2 {mu}m SSZ and 4 {mu}m SDC using tape casting, screen printing, and co-firing processes. The cell reached power densities of 0.54 W cm{sup -2} at 650 C and 0.85 W cm{sup -2} at 700 C, with open circuit voltage (OCV) values larger than 1.02 V. The electrical leaking between anode and cathode through an SDC electrolyte has been blocked in the bi-layered electrolyte structure. However, both the electrolyte resistance (R{sub el}) and electrode polarization resistance (R{sub p,a+c}) increased in comparison to cells with single-layered SDC electrolytes. The formation of a solid solution of (Ce, Zr)O{sub 2-x} during sintering process and the flaws in the bi-layered electrolyte structure seem to be the main causes for the increase in the R{sub el} value (0.32 {omega} cm{sup 2}) at 650 C, which is almost one order of magnitude higher than the calculated value. (author)

  15. Solid oxide fuel cells towards real life applications. Final report

    Energy Technology Data Exchange (ETDEWEB)

    2010-07-01

    Solid Oxide Fuel Cells offer a clean and efficient way of producing electricity and heat from a wide selection of fuels. The project addressed three major challenges to be overcome by the technology to make commercialisation possible. (1) At the cell level, increased efficiency combined with production cost reduction has been achieved through an optimization of the manufacturing processes, b) by using alternative raw materials with a lower purchase price and c) by introducing a new generation of fuel cells with reduced loss and higher efficiency. (2) At the stack level, production cost reduction is reduced and manufacturing capacity is increased through an optimization of the stack production. (3) At the system level, development of integrated hotbox concepts for the market segments distributed generation (DG), micro combined heat and power (mCHP), and auxiliary power units (APU) have been developed. In the mCHP segment, two concepts have been developed and validated with regards to market requirements and scalability. In the APU-segment, different types of reformers have been tested and it has been proven that diesel can be reformed through appropriate reformers. Finally, operation experience and feedback has been gained by deployment of stacks in the test facility at the H.C. OErsted Power Plant (HCV). This demonstration has been carried out in collaboration between TOFC and DONG Energy Power A/S (DONG), who has participated as a subcontractor to TOFC. The demonstration has given valuable knowledge and experience with design, start-up and operation of small power units connected to the grid and future development within especially the mCHP segment will benefit from this. In this report, the project results are described for each of the work packages in the project. (Author)

  16. Design considerations for a pressure-driven multi-stage rocket

    Science.gov (United States)

    Sauerwein, Steven Craig

    2002-01-01

    The purpose of this study was to examine the feasibility of using propellant tank pressurization to eliminate the use of high-pressure turbopumps in multi-stage liquid-fueled satellite launchers. Several new technologies were examined to reduce the mass of such a rocket. Composite materials have a greater strength-to-weight ratio than metals and can be used to reduce the weight of rocket propellant tanks and structure. Catalytically combined hydrogen and oxygen can be used to heat pressurization gas, greatly reducing the amount of gas required. Ablatively cooled rocket engines can reduce the complexity and cost of the rocket. Methods were derived to estimate the mass of the various rocket components. These included a method to calculate the amount of gas needed to pressurize a propellant tank by modeling the behavior of the pressurization gas as the liquid propellant flows out of the tank. A way to estimate the mass and size of a ablatively cooled composite cased rocket engine. And a method to model the flight of such a rocket through the atmosphere in conjunction with optimization of the rockets trajectory. The results show that while a liquid propellant rocket using tank pressurization are larger than solid propellant rockets and turbopump driven liquid propellant rockets, they are not impractically large.

  17. Large eddy simulation of combustion characteristics in a kerosene fueled rocket-based combined-cycle engine combustor

    Science.gov (United States)

    Huang, Zhi-wei; He, Guo-qiang; Qin, Fei; Cao, Dong-gang; Wei, Xiang-geng; Shi, Lei

    2016-10-01

    This study reports combustion characteristics of a rocket-based combined-cycle engine combustor operating at ramjet mode numerically. Compressible large eddy simulation with liquid kerosene sprayed and vaporized is used to study the intrinsic unsteadiness of combustion in such a propulsion system. Results for the pressure oscillation amplitude and frequency in the combustor as well as the wall pressure distribution along the flow-path, are validated using experimental data, and they show acceptable agreement. Coupled with reduced chemical kinetics of kerosene, results are compared with the simultaneously obtained Reynolds-Averaged Navier-Stokes results, and show significant differences. A flow field analysis is also carried out for further study of the turbulent flame structures. Mixture fraction is used to determine the most probable flame location in the combustor at stoichiometric condition. Spatial distributions of the Takeno flame index, scalar dissipation rate, and heat release rate reveal that different combustion modes, such as premixed and non-premixed modes, coexisted at different sections of the combustor. The RBCC combustor is divided into different regions characterized by their non-uniform features. Flame stabilization mechanism, i.e., flame propagation or fuel auto-ignition, and their relative importance, is also determined at different regions in the combustor.

  18. Biomass-powered Solid Oxide Fuel Cells : Experimental and Modeling Studies for System Integrations

    NARCIS (Netherlands)

    Liu, M.

    2013-01-01

    Biomass is a sustainable energy source which, through thermo-chemical processes of biomass gasification, is able to be converted from a solid biomass fuel into a gas mixture, known as syngas or biosyngas. A solid oxide fuel cell (SOFC) is a power generation device that directly converts the chemical

  19. Thermodynamic analysis of SOFC (solid oxide fuel cell) - Stirling hybrid plants using alternative fuels

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2013-01-01

    A novel hybrid power system (∼10 kW) for an average family home is proposed. The system investigated contains a solid oxide fuel cell (SOFC) on top of a Stirling engine. The off-gases produced in the SOFC cycle are fed to a bottoming Stirling engine, at which additional power is generated...... to that of a stand-alone Stirling engine or SOFC plant. For the combined SOFC and Stirling configuration, the overall power production was increased by approximately 10% compared to that of a stand-alone SOFC plant. System efficiencies of approximately 60% are achieved, which is remarkable for such small plant sizes...

  20. Hydrogen sulfide-powered solid oxide fuel cells

    Science.gov (United States)

    Liu, Man

    2004-12-01

    The potential utilization of hydrogen sulfide as fuel in solid oxide fuel cells has been investigated using an oxide-ion conducting YSZ electrolyte and different kinds of anode catalysts at operating temperatures in the range of 700--900°C and at atmospheric pressure. This technology offers an economically attractive alternative to present methods for removing toxic and corrosive H2S gas from sour gas streams and a promising approach for cogenerating electrical energy and useful chemicals. The primary objective of the present research was to find active and stable anode materials. Fuel cell experimental results showed that platinum was a good electrocatalyst for the conversion of H2S, but the Pt/YSZ interface was physically unstable due to the reversible formation and decomposition of PtS in H 2S streams at elevated temperatures. Moreover, instability of the Pt/YSZ interface was accelerated significantly by electrochemical reactions, and ultimately led to the detachment of the Pt anode from the electrolyte. It has been shown that an interlayer of TiO2 stabilized the Pt anode on YSZ electrolyte, thereby prolonging cell lifetime. However, the current output for a fuel cell using Pt/TiO2 as anode was not improved compared to using Pt alone. It was therefore necessary to investigate novel anode systems for H 2S-air SOFCs. New anode catalysts comprising composite metal sulfides were developed. These catalysts exhibited good electrical conductivity and better catalytic activity than Pt. In contrast to MoS2 alone, composite catalysts (M-Mo-S, M = Fe, Co, Ni) were not volatile and had superior stability. However, when used for extended periods of time, detachment of Pt current collecting film from anodes comprising metal sulfides alone resulted in a large increase in contact resistance and reduction in cell performance. Consequently, a systematic investigation was conducted to identify alternative electronic conductors for use with M-Mo-S catalysts. Anode catalysts

  1. Modeling solid-fuel dispersal during slow loss-of-flow-type transients

    International Nuclear Information System (INIS)

    DiMelfi, R.J.; Fenske, G.R.

    1981-01-01

    The dispersal, under certain accident conditions, of solid particles of fast-reactor fuel is examined in this paper. In particular, we explore the possibility that solid-fuel fragmentation and dispersal can be driven by expanding fission gas, during a slow LOF-type accident. The consequences of fragmentation are studied in terms of the size and speed of dispersed particles, and the overall quantity of fuel moved. (orig.)

  2. Understanding Our Energy Footprint: Undergraduate Chemistry Laboratory Investigation of Environmental Impacts of Solid Fossil Fuel Wastes

    Science.gov (United States)

    Berger, Michael; Goldfarb, Jillian L.

    2017-01-01

    Engaging undergraduates in the environmental consequences of fossil fuel usage primes them to consider their own anthropogenic impact, and the benefits and trade-offs of converting to renewable fuel strategies. This laboratory activity explores the potential contaminants (both inorganic and organic) present in the raw fuel and solid waste…

  3. Solid fuel residues inventory of fixtures and perspectives. Extended abstract

    International Nuclear Information System (INIS)

    Bicocchi, S.; Tenza, A.

    2008-01-01

    The solid fuel residues, so called CSR, represent a fraction with high Lower Calorific value, with physicochemical characteristics conferring them the capacity to replace usual fuels. These last years, industrial applications seem to develop all over Europe. The present study thus sticks to draw up a panorama of the European situation in 2007. It develops the global regulation and normative context in which this waste processing channel must fit, while waiting for the presentation of the new Framework Directive of Waste during 2008, and the initiatives of certain precursory countries like Italy, Germany and the Netherlands. A scientific and technical inventory is presented being based on concrete cases identified within the Community territory. The study examines in particular a representative sample of 11 countries observed (Germany, Austria, Belgium, Spain, France, Italy, Netherlands, Finland, Denmark, Sweden and United Kingdom) and points out the local context, the layer and the practices developed in the use of this fraction. Finally, the study tries to position the French case in the European overview and highlights certain conditions (success factors, obstacles) allowing the development of CSR channel. Until few time, the CSR channel has increased without established regulation and normative framework. The diversity of the trade names listed through Europe testifies to the absence of common framework. To date, term CSR doesn't exist in European legislation. Only nomenclature NAPFUE (support for the declaration of the emissions in atmosphere) identifies fuels including the CSR. The working group CEN TC 343 (M325 Mandate) indicates that it only acts of solid waste, non made up of biomass, resulting from waste non dangerous and intended to be used in incineration or co-incineration. Regarding to existing European directives, a global tendency for the development of the channel is identified (management of waste, energy, environment). Thus, the objectives of

  4. Designing and optimization of a micro CHP system based on Solid Oxide Fuel Cell with different fuel processing technologies

    DEFF Research Database (Denmark)

    Liso, Vincenzo; Nielsen, Mads Pagh; Kær, Søren Knudsen

    2009-01-01

    are the possibility to partially reform hydrocarbon in the fuel cell anode compartment and the possibility to use high quality heat for cogeneration. In this work, different configurations of solid oxide fuel cell system for decentralized electricity production are examined. The Balance of Plant (BoP) components...

  5. Nitrato-Functionalized Task-Specific Ionic Liquids as Attractive Hypergolic Rocket Fuels.

    Science.gov (United States)

    Wang, Yi; Huang, Shi; Zhang, Wenquan; Liu, Tianlin; Qi, Xiujuan; Zhang, Qinghua

    2017-09-12

    Hypergolic ionic liquids (HILs) as potential replacements for hydrazine derivatives have attracted increasing interest over the last decade. Previous studies on HILs have mostly concentrated on the anionic innovations of ionic liquids to shorten the ignition delay (ID) time, but little attention has been paid to cationic modifications and their structure-property relationships. In this work, we present a new strategy of cationic functionalization by introducing the energetic nitrato group into the cationic units of HILs. Interestingly, the introduction of oxygen-rich nitrato groups into the cationic structure significantly improved the combustion performance of HILs with larger flame diameters and duration times. The density-specific impulse (ρI sp ) of these novel HILs are all above 279.0 s g cm -3 , much higher than that of UDMH (215.7 s g cm -3 ). In addition, the densities of these HILs are in the range of 1.22-1.39 g cm -3 , which is much higher than that of UDMH (0.79 g cm -3 ), showing their higher loading capacity than hydrazine-derived fuels in a propellant tank. This promising strategy of introducing nitrato groups into the cationic structures has provided a new platform for developing high-performing HILs with improved combustion properties. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Flow instability tests for a particle bed reactor nuclear thermal rocket fuel element

    Science.gov (United States)

    Lawrence, Timothy J.

    1993-05-01

    Recent analyses have focused on the flow stability characteristics of a particle bed reactor (PBR). These laminar flow instabilities may exist in reactors with parallel paths and are caused by the heating of the gas at low Reynolds numbers. This phenomena can be described as follows: several parallel channels are connected at the plenum regions and are stabilized by some inlet temperature and pressure; a perturbation in one channel causes the temperature to rise and increases the gas viscosity and reduces the gas density; the pressure drop is fixed by the plenum regions, therefore, the mass flow rate in the channel would decrease; the decrease in flow reduces the ability to remove the energy added and the temperature increases; and finally, this process could continue until the fuel element fails. Several analyses based on different methods have derived similar curves to show that these instabilities may exist at low Reynolds numbers and high phi's ((Tfinal Tinitial)/Tinitial). These analyses need to be experimentally verified.

  7. An evaluation of the total quality management implementation strategy for the advanced solid rocket motor project at NASA's Marshall Space Flight Center. M.S. Thesis - Tennessee Univ.

    Science.gov (United States)

    Schramm, Harry F.; Sullivan, Kenneth W.

    1991-01-01

    An evaluation of the NASA's Marshall Space Flight Center (MSFC) strategy to implement Total Quality Management (TQM) in the Advanced Solid Rocket Motor (ASRM) Project is presented. The evaluation of the implementation strategy reflected the Civil Service personnel perspective at the project level. The external and internal environments at MSFC were analyzed for their effects on the ASRM TQM strategy. Organizational forms, cultures, management systems, problem solving techniques, and training were assessed for their influence on the implementation strategy. The influence of ASRM's effort was assessed relative to its impact on mature projects as well as future projects at MSFC.

  8. Carbon deposition thresholds on nickel-based solid oxide fuel cell anodes I. Fuel utilization

    Science.gov (United States)

    Kuhn, J.; Kesler, O.

    2015-03-01

    In the first of a two part publication, the effect of fuel utilization (Uf) on carbon deposition rates in solid oxide fuel cell nickel-based anodes was studied. Representative 5-component CH4 reformate compositions (CH4, H2, CO, H2O, & CO2) were selected graphically by plotting the solutions to a system of mass-balance constraint equations. The centroid of the solution space was chosen to represent a typical anode gas mixture for each nominal Uf value. Selected 5-component and 3-component gas mixtures were then delivered to anode-supported cells for 10 h, followed by determination of the resulting deposited carbon mass. The empirical carbon deposition thresholds were affected by atomic carbon (C), hydrogen (H), and oxygen (O) fractions of the delivered gas mixtures and temperature. It was also found that CH4-rich gas mixtures caused irreversible damage, whereas atomically equivalent CO-rich compositions did not. The coking threshold predicted by thermodynamic equilibrium calculations employing graphite for the solid carbon phase agreed well with empirical thresholds at 700 °C (Uf ≈ 32%); however, at 600 °C, poor agreement was observed with the empirical threshold of ∼36%. Finally, cell operating temperatures correlated well with the difference in enthalpy between the supplied anode gas mixtures and their resulting thermodynamic equilibrium gas mixtures.

  9. Technical meeting on 'Review of solid and mobile fuels for partitioning and transmutation systems'. Working material

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    The topics covered during the Meeting were divided into two Sessions. Session 1 - Qualification of Solid and Mobile Fuels delt with: Neutronic, fuel and material properties of a molten salt transmuter; and Preliminary analysis of transmutation fuels for KALIMER. Session 2 - Reactor Physics and Safety Characteristics of Transmutation Systems based on Solid and Mobile Fuel Types included the following: Activity in NEA for P and T area; IAEA activities in the area of partitioning and transmutation; The R and D activity in Brazil: A conceptual fast energy amplifier ADS cooled by helium double stata Th/U fuel cycle; Closed fuel cycle and contemporary tendencies of the nuclear facilities development; Current Russian activities in P and T area; Pyrochemical reprocessing and nuclear spent fuel disposal project; Fuel selection criteria specific for double stratum minor actinide burners.

  10. Solid recovered fuel: influence of waste stream composition and processing on chlorine content and fuel quality.

    Science.gov (United States)

    Velis, Costas; Wagland, Stuart; Longhurst, Phil; Robson, Bryce; Sinfield, Keith; Wise, Stephen; Pollard, Simon

    2012-02-07

    Solid recovered fuel (SRF) produced by mechanical-biological treatment (MBT) of municipal waste can replace fossil fuels, being a CO(2)-neutral, affordable, and alternative energy source. SRF application is limited by low confidence in quality. We present results for key SRF properties centered on the issue of chlorine content. A detailed investigation involved sampling, statistical analysis, reconstruction of composition, and modeling of SRF properties. The total chlorine median for a typical plant during summer operation was 0.69% w/w(d), with lower/upper 95% confidence intervals of 0.60% w/w(d) and 0.74% w/w(d) (class 3 of CEN Cl indicator). The average total chlorine can be simulated, using a reconciled SRF composition before shredding to limit for ash content marginally below the 20% w/w(d) deemed suitable for certain power plants; and a lower 95% confidence limit of net calorific value (NCV) at 14.5 MJ kg(ar)(-1). The data provide, for the first time, a high level of confidence on the effects of SRF composition on its chlorine content, illustrating interrelationships with other fuel properties. The findings presented here allow rational debate on achievable vs desirable MBT-derived SRF quality, informing the development of realistic SRF quality specifications, through modeling exercises, needed for effective thermal recovery.

  11. Structures of the particles of the condensed dispersed phase in solid fuel combustion products plasma

    International Nuclear Information System (INIS)

    Samaryan, A.A.; Chernyshev, A.V.; Nefedov, A.P.; Petrov, O.F.; Fortov, V.E.; Mikhailov, Yu.M.; Mintsev, V.B.

    2000-01-01

    The results of experimental investigations of a type of dusty plasma which has been least studied--the plasma of solid fuel combustion products--were presented. Experiments to determine the parameters of the plasma of the combustion products of synthetic solid fuels with various compositions together with simultaneous diagnostics of the degree of ordering of the structures of the particles of the dispersed condensed phase were performed. The measurements showed that the charge composition of the plasma of the solid fuels combustion products depends strongly on the easily ionized alkali-metal impurities which are always present in synthetic fuel in one or another amount. An ordered arrangement of the particles of a condensed dispersed phase in structures that form in a boundary region between the high-temperature and condensation zones was observed for samples of aluminum-coated solid fuels with a low content of alkali-metal impurities

  12. Robotic Manufacturing of 5.5 Meter Cryogenic Fuel Tank Dome Assemblies for the NASA Ares I Rocket

    Science.gov (United States)

    Jones, Ronald E.

    2012-01-01

    The Ares I rocket is the first launch vehicle scheduled for manufacture under the National Aeronautic and Space Administration's (NASA's) Constellation program. A series of full-scale Ares I development articles have been constructed on the Robotic Weld Tool at the NASA George C. Marshall Space Flight Center in Huntsville, Alabama. The Robotic Weld Tool is a 100 ton, 7-axis, robotic manufacturing system capable of machining and friction stir welding large-scale space hardware. This presentation will focus on the friction stir welding of 5.5m diameter cryogenic fuel tank components; specifically, the liquid hydrogen forward dome (LH2 MDA), the common bulkhead manufacturing development articles (CBMDA) and the thermal protection system demonstration dome (TPS Dome). The LH2 MDA was the first full-scale, flight-like Ares I hardware produced under the Constellation Program. It is a 5.5m diameter elliptical dome assembly consisting of eight gore panels, a y-ring stiffener and a manhole fitting. All components are made from aluminumlithium alloy 2195. Conventional and self-reacting friction stir welding was used on this article. An overview of the manufacturing processes will be discussed. The LH2 MDA is the first known fully friction stir welded dome ever produced. The completion of four Common Bulkhead Manufacturing Development Articles (CBMDA) and the TPS Dome will also be highlighted. Each CBMDA and the TPS Dome consists of a 5.5m diameter spun-formed dome friction stir welded to a y-ring stiffener. The domes and y-rings are made of aluminum 2014 and 2219 respectively. The TPS Dome has an additional aluminum alloy 2195 barrel section welded to the y-ring. Manufacturing solutions will be discussed including "fixtureless" welding with self reacting friction stir welding.

  13. Manufacturing of 5.5 Meter Diameter Cryogenic Fuel Tank Domes for the NASA Ares I Rocket

    Science.gov (United States)

    Jones, Ronald E.; Carter, Robert W.

    2012-01-01

    The Ares I rocket is the first launch vehicle scheduled for manufacture under the National Aeronautic and Space Administration s (NASA s) Constellation program. A series of full-scale Ares I development articles have been constructed on the Robotic Weld Tool at the NASA George C. Marshall Space Flight Center in Huntsville, Alabama. The Robotic Weld Tool is a 100 ton, 7-axis, robotic manufacturing system capable of machining and friction stir welding large-scale space hardware. This presentation will focus on the friction stir welding of 5.5m diameter cryogenic fuel tank components; specifically, the liquid hydrogen forward dome (LH2 MDA) and the common bulkhead manufacturing development articles (CBMDA). The LH2 MDA was the first full-scale, flight-like Ares I hardware produced under the Constellation Program. It is a 5.5m diameter elliptical dome assembly consisting of eight gore panels, a y-ring stiffener and a manhole fitting. All components are made from aluminum-lithium alloy 2195. Conventional and self-reacting friction stir welding was used on this article. Manufacturing solutions will be discussed including the implementation of photogrammetry, an advanced metrology technique, as well as fixtureless welding. The LH2 MDA is the first known fully friction stir welded dome ever produced. The completion of four Common Bulkhead Manufacturing Development Articles (CBMDA) will also be highlighted. Each CBMDA consists of a 5.5m diameter spun-formed dome friction stir welded to a y-ring stiffener. The domes and y-rings are made of aluminum 2014 and 2219 respectively. An overview of CBMDA manufacturing processes and the effect of tooling on weld defect formation will be discussed.

  14. Thermal imaging of solid oxide fuel cell anode processes

    Energy Technology Data Exchange (ETDEWEB)

    Pomfret, Michael B.; Kidwell, David A.; Owrutsky, Jeffrey C. [Chemistry Division, U.S. Naval Research Laboratory, Washington, DC 20375 (United States); Steinhurst, Daniel A. [Nova Research Inc., Alexandria, VA 22308 (United States)

    2010-01-01

    A Si-charge-coupled device (CCD), camera-based, near-infrared imaging system is demonstrated on Ni/yttria-stabilized zirconia (YSZ) fragments and the anodes of working solid oxide fuel cells (SOFCs). NiO reduction to Ni by H{sub 2} and carbon deposition lead to the fragment cooling by 5 {+-} 2 C and 16 {+-} 1 C, respectively. When air is flowed over the fragments, the temperature rises 24 {+-} 1 C as carbon and Ni are oxidized. In an operational SOFC, the decrease in temperature with carbon deposition is only 4.0 {+-} 0.1 C as the process is moderated by the presence of oxides and water. Electrochemical oxidation of carbon deposits results in a {delta}T of +2.2 {+-} 0.2 C, demonstrating that electrochemical oxidation is less vigorous than atmospheric oxidation. While the high temperatures of SOFCs are challenging in many respects, they facilitate thermal imaging because their emission overlaps the spectral response of inexpensive Si-CCD cameras. Using Si-CCD cameras has advantages in terms of cost, resolution, and convenience compared to mid-infrared thermal cameras. High spatial ({proportional_to}0.1 mm) and temperature ({proportional_to}0.1 C) resolutions are achieved in this system. This approach provides a convenient and effective analytical technique for investigating the effects of anode chemistry in operating SOFCs. (author)

  15. Thermal imaging of solid oxide fuel cell anode processes

    Science.gov (United States)

    Pomfret, Michael B.; Steinhurst, Daniel A.; Kidwell, David A.; Owrutsky, Jeffrey C.

    A Si-charge-coupled device (CCD), camera-based, near-infrared imaging system is demonstrated on Ni/yttria-stabilized zirconia (YSZ) fragments and the anodes of working solid oxide fuel cells (SOFCs). NiO reduction to Ni by H 2 and carbon deposition lead to the fragment cooling by 5 ± 2 °C and 16 ± 1 °C, respectively. When air is flowed over the fragments, the temperature rises 24 ± 1 °C as carbon and Ni are oxidized. In an operational SOFC, the decrease in temperature with carbon deposition is only 4.0 ± 0.1 °C as the process is moderated by the presence of oxides and water. Electrochemical oxidation of carbon deposits results in a Δ T of +2.2 ± 0.2 °C, demonstrating that electrochemical oxidation is less vigorous than atmospheric oxidation. While the high temperatures of SOFCs are challenging in many respects, they facilitate thermal imaging because their emission overlaps the spectral response of inexpensive Si-CCD cameras. Using Si-CCD cameras has advantages in terms of cost, resolution, and convenience compared to mid-infrared thermal cameras. High spatial (∼0.1 mm) and temperature (∼0.1 °C) resolutions are achieved in this system. This approach provides a convenient and effective analytical technique for investigating the effects of anode chemistry in operating SOFCs.

  16. Internal reforming of methane in solid oxide fuel cell systems

    Science.gov (United States)

    Peters, R.; Dahl, R.; Klüttgen, U.; Palm, C.; Stolten, D.

    Internal reforming is an attractive option offering a significant cost reduction, higher efficiencies and faster load response of a solid oxide fuel cell (SOFC) power plant. However, complete internal reforming may lead to several problems which can be avoided with partial pre-reforming of natural gas. In order to achieve high total plant efficiency associated with low energy consumption and low investment costs, a process concept has been developed based on all the components of the SOFC system. In the case of anode gas recycling an internal steam circuit exists. This has the advantage that there is no need for an external steam generator and the steam concentration in the anode gas is reduced. However, anode gas recycling has to be proven by experiments in a pre-reformer and for internal reforming. The addition of carbon dioxide clearly shows a decrease in catalyst activity, while for temperatures higher than 1000 K hydrogen leads to an increase of the measured methane conversion rates.

  17. Constrained Sintering in Fabrication of Solid Oxide Fuel Cells.

    Science.gov (United States)

    Lee, Hae-Weon; Park, Mansoo; Hong, Jongsup; Kim, Hyoungchul; Yoon, Kyung Joong; Son, Ji-Won; Lee, Jong-Ho; Kim, Byung-Kook

    2016-08-09

    Solid oxide fuel cells (SOFCs) are inevitably affected by the tensile stress field imposed by the rigid substrate during constrained sintering, which strongly affects microstructural evolution and flaw generation in the fabrication process and subsequent operation. In the case of sintering a composite cathode, one component acts as a continuous matrix phase while the other acts as a dispersed phase depending upon the initial composition and packing structure. The clustering of dispersed particles in the matrix has significant effects on the final microstructure, and strong rigidity of the clusters covering the entire cathode volume is desirable to obtain stable pore structure. The local constraints developed around the dispersed particles and their clusters effectively suppress generation of major process flaws, and microstructural features such as triple phase boundary and porosity could be readily controlled by adjusting the content and size of the dispersed particles. However, in the fabrication of the dense electrolyte layer via the chemical solution deposition route using slow-sintering nanoparticles dispersed in a sol matrix, the rigidity of the cluster should be minimized for the fine matrix to continuously densify, and special care should be taken in selecting the size of the dispersed particles to optimize the thermodynamic stability criteria of the grain size and film thickness. The principles of constrained sintering presented in this paper could be used as basic guidelines for realizing the ideal microstructure of SOFCs.

  18. Constrained Sintering in Fabrication of Solid Oxide Fuel Cells

    Science.gov (United States)

    Lee, Hae-Weon; Park, Mansoo; Hong, Jongsup; Kim, Hyoungchul; Yoon, Kyung Joong; Son, Ji-Won; Lee, Jong-Ho; Kim, Byung-Kook

    2016-01-01

    Solid oxide fuel cells (SOFCs) are inevitably affected by the tensile stress field imposed by the rigid substrate during constrained sintering, which strongly affects microstructural evolution and flaw generation in the fabrication process and subsequent operation. In the case of sintering a composite cathode, one component acts as a continuous matrix phase while the other acts as a dispersed phase depending upon the initial composition and packing structure. The clustering of dispersed particles in the matrix has significant effects on the final microstructure, and strong rigidity of the clusters covering the entire cathode volume is desirable to obtain stable pore structure. The local constraints developed around the dispersed particles and their clusters effectively suppress generation of major process flaws, and microstructural features such as triple phase boundary and porosity could be readily controlled by adjusting the content and size of the dispersed particles. However, in the fabrication of the dense electrolyte layer via the chemical solution deposition route using slow-sintering nanoparticles dispersed in a sol matrix, the rigidity of the cluster should be minimized for the fine matrix to continuously densify, and special care should be taken in selecting the size of the dispersed particles to optimize the thermodynamic stability criteria of the grain size and film thickness. The principles of constrained sintering presented in this paper could be used as basic guidelines for realizing the ideal microstructure of SOFCs. PMID:28773795

  19. HIGH-TEMPERATURE TUBULAR SOLID OXIDE FUEL CELL GENERATOR DEVELOPMENT

    Energy Technology Data Exchange (ETDEWEB)

    S.E. Veyo

    1998-09-01

    During the Westinghouse/USDOE Cooperative Agreement period of November 1, 1990 through November 30, 1997, the Westinghouse solid oxide fuel cell has evolved from a 16 mm diameter, 50 cm length cell with a peak power of 1.27 watts/cm to the 22 mm diameter, 150 cm length dimensions of today's commercial prototype cell with a peak power of 1.40 watts/cm. Accompanying the increase in size and power density was the elimination of an expensive EVD step in the manufacturing process. Demonstrated performance of Westinghouse's tubular SOFC includes a lifetime cell test which ran for a period in excess of 69,000 hours, and a fully integrated 25 kWe-class system field test which operated for over 13,000 hours at 90% availability with less than 2% performance degradation over the entire period. Concluding the agreement period, a 100 kW SOFC system successfully passed its factory acceptance test in October 1997 and was delivered in November to its demonstration site in Westervoort, The Netherlands.

  20. A Green, Safe, Dual-pulse Solid Motor for CubeSat Orbit Changing, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Small satellites such as CubeSats are in need of responsive propulsion, but are limited due to their size. Though single pulse, AP/HTPB fueled solid rocket motors...

  1. Elemental balance of SRF production process: solid recovered fuel produced from municipal solid waste.

    Science.gov (United States)

    Nasrullah, Muhammad; Vainikka, Pasi; Hannula, Janne; Hurme, Markku; Oinas, Pekka

    2016-01-01

    In the production of solid recovered fuel (SRF), certain waste components have excessive influence on the quality of product. The proportion of rubber, plastic (hard) and certain textiles was found to be critical as to the elemental quality of SRF. The mass flow of rubber, plastic (hard) and textiles (to certain extent, especially synthetic textile) components from input waste stream into the output streams of SRF production was found to play the decisive role in defining the elemental quality of SRF. This paper presents the mass flow of polluting and potentially toxic elements (PTEs) in SRF production. The SRF was produced from municipal solid waste (MSW) through mechanical treatment (MT). The results showed that of the total input chlorine content to process, 55% was found in the SRF and 30% in reject material. Of the total input arsenic content, 30% was found in the SRF and 45% in fine fraction. In case of cadmium, lead and mercury, of their total input content to the process, 62%, 38% and 30%, respectively, was found in the SRF. Among the components of MSW, rubber material was identified as potential source of chlorine, containing 8.0 wt.% of chlorine. Plastic (hard) and textile components contained 1.6 and 1.1. wt.% of chlorine, respectively. Plastic (hard) contained higher lead and cadmium content compared with other waste components, i.e. 500 mg kg(-1) and 9.0 mg kg(-1), respectively. © The Author(s) 2015.

  2. Combustion Characteristics of Chlorine-Free Solid Fuel Produced from Municipal Solid Waste by Hydrothermal Processing

    Directory of Open Access Journals (Sweden)

    Kunio Yoshikawa

    2012-11-01

    Full Text Available An experimental study on converting municipal solid waste (MSW into chlorine-free solid fuel using a combination of hydrothermal processing and water-washing has been performed. After the product was extracted from the reactor, water-washing experiments were then conducted to obtain chlorine-free products with less than 3000 ppm total chlorine content. A series of combustion experiments were then performed for the products before and after the washing process to determine the chlorine content in the exhaust gas and those left in the ash after the combustion process at a certain temperature. A series of thermogravimetric analyses were also conducted to compare the combustion characteristics of the products before and after the washing process. Due to the loss of ash and some volatile matter after washing process, there were increases in the fixed carbon content and the heating value of the product. Considering the possible chlorine emission, the washing process after the hydrothermal treatment should be necessary only if the furnace temperature is more than 800 °C.

  3. Design study of laser fusion rocket

    International Nuclear Information System (INIS)

    Nakashima, Hideki; Shoyama, Hidetoshi; Kanda, Yukinori

    1991-01-01

    A design study was made on a rocket powered by laser fusion. Dependence of its flight performance on target gain, driver repetition rate and fuel composition was analyzed to obtain optimal design parameters of the laser fusion rocket. The results indicate that the laser fusion rocket fueled with DT or D 3 He has the potential advantages over other propulsion systems such as fission rocket for interplanetary travel. (author)

  4. Status of solid polymer electrolyte fuel cell technology and potential for transportation applications

    Science.gov (United States)

    McElroy, J. F.; Nuttall, L. J.

    The solid polymer electrolyte (SPE) fuel cell represents the first fuel cell technology known to be used operationally. Current activities are mainly related to the development of a space regenerative fuel cell system for energy storage on board space stations, or other large orbiting vehicles and platforms. During 1981, a study was performed to determine the feasibility of using SPE fuel cells for automotive or other vehicular applications, using methanol as the fuel. The results of this study were very encouraging. Details concerning a conceptual automotive fuel cell power plant study are discussed, taking into account also a layout of major components for compact passenger car installation.

  5. Simultaneous analysis of qualitative parameters of solid fuel using complex neutron gamma method

    International Nuclear Information System (INIS)

    Dombrovskij, V.P.; Ajtsev, N.I.; Ryashchikov, V.I.; Frolov, V.K.

    1983-01-01

    A study was made on complex neutron gamma method for simultaneous analysis of carbon content, ash content and humidity of solid fuel according to gamma radiation of inelastic fast neutron scattering and radiation capture of thermal neutrons. Metrological characteristics of pulse and stationary neutron gamma methods for determination of qualitative solid fuel parameters were analyzed, taking coke breeze as an example. Optimal energy ranges of gamma radiation detection (2-8 MeV) were determined. The advantages of using pulse neutron generator for complex analysis of qualitative parameters of solid fuel in large masses were shown

  6. Rocket Flight.

    Science.gov (United States)

    Van Evera, Bill; Sterling, Donna R.

    2002-01-01

    Describes an activity for designing, building, and launching rockets that provides students with an intrinsically motivating and real-life application of what could have been classroom-only concepts. Includes rocket design guidelines and a sample grading rubric. (KHR)

  7. Hydrocarbon fuel processing of micro solid oxide fuel cell systems[Dissertation 17455

    Energy Technology Data Exchange (ETDEWEB)

    Stutz, M. J.

    2007-07-01

    The scope of this thesis is the numerical and experimental investigation of the fuel processing of a micro solid oxide fuel cell (SOFC) running on hydrocarbon fuel. The goal is to enhance the overall system efficiency by optimization of the reforming process in the steady state and the improvement of the start-up process. Micro SOFC are a potential alternative to the currently used batteries in portable devices. Liquid butane in a cartridge could be the energy source. This dissertation is focused on the fuel processing of the system, namely the reforming and post-combusting processes. The reformer converts the hydrocarbon fuel to a hydrogen rich gas that can be utilized by the SOFC. The post-combustor depletes the toxic and/or explosive gases before leaving the exhaust. Chapter One presents a short introduction to the field of hydrocarbon fuel processing in micro solid oxide fuel cell systems, the next three chapters deal with computational modeling of the transport phenomena inside a micro-reformer, which leads to a better understanding of the chemistry and the physics therein, hence progress in the design and operation parameters. The experimental part (i.e. Chapter Five) of this thesis focuses on the feasibility of a novel hybrid start-up method of a fuel cell system that employs existing components as an additional heat source. In Chapter Two the effect of wall heat conduction on the syngas (hydrogen and carbon monoxide) production of a micro-reformer, representing micro-fabricated channels or monoliths, is investigated. Methane is used as a model hydrocarbon fuel since its heterogeneous reaction path on rhodium is known and validated. The simulations demonstrate that the axial wall conduction strongly influences the performance of the micro-reformer and should not be neglected without a careful a priori investigation of its impact. Methane conversion and hydrogen yield are strongly dependent of the wall inner surface temperature, which is influenced by the

  8. Generation of transportation fuel from solid municipal waste plastics

    Energy Technology Data Exchange (ETDEWEB)

    Sarker, Moinuddin

    2010-09-15

    Transportation fuels derived from fossil fuels are subjected to the price fluctuations of the global marketplace, and constitute a major expense in the operation of a vehicle. Emissions from the evaporation and combustion of these fuels contribute to a range of environmental problems, causing poor air quality and emitting greenhouse gases that contribute to global warming. Alternative fuels created from domestic sources have been proposed as a solution to these problems, and many fuels are being developed based on biomass and other renewable sources. Natural State Research, Inc. developed different alternative hydrocarbon fuel which is produced from waste plastic materials.

  9. Plasma Membranes Modified by Plasma Treatment or Deposition as Solid Electrolytes for Potential Application in Solid Alkaline Fuel Cells

    Science.gov (United States)

    Reinholdt, Marc; Ilie, Alina; Roualdès, Stéphanie; Frugier, Jérémy; Schieda, Mauricio; Coutanceau, Christophe; Martemianov, Serguei; Flaud, Valérie; Beche, Eric; Durand, Jean

    2012-01-01

    In the highly competitive market of fuel cells, solid alkaline fuel cells using liquid fuel (such as cheap, non-toxic and non-valorized glycerol) and not requiring noble metal as catalyst seem quite promising. One of the main hurdles for emergence of such a technology is the development of a hydroxide-conducting membrane characterized by both high conductivity and low fuel permeability. Plasma treatments can enable to positively tune the main fuel cell membrane requirements. In this work, commercial ADP-Morgane® fluorinated polymer membranes and a new brand of cross-linked poly(aryl-ether) polymer membranes, named AMELI-32®, both containing quaternary ammonium functionalities, have been modified by argon plasma treatment or triallylamine-based plasma deposit. Under the concomitant etching/cross-linking/oxidation effects inherent to the plasma modification, transport properties (ionic exchange capacity, water uptake, ionic conductivity and fuel retention) of membranes have been improved. Consequently, using plasma modified ADP-Morgane® membrane as electrolyte in a solid alkaline fuel cell operating with glycerol as fuel has allowed increasing the maximum power density by a factor 3 when compared to the untreated membrane. PMID:24958295

  10. Plasma membranes modified by plasma treatment or deposition as solid electrolytes for potential application in solid alkaline fuel cells.

    Science.gov (United States)

    Reinholdt, Marc; Ilie, Alina; Roualdès, Stéphanie; Frugier, Jérémy; Schieda, Mauricio; Coutanceau, Christophe; Martemianov, Serguei; Flaud, Valérie; Beche, Eric; Durand, Jean

    2012-07-30

    In the highly competitive market of fuel cells, solid alkaline fuel cells using liquid fuel (such as cheap, non-toxic and non-valorized glycerol) and not requiring noble metal as catalyst seem quite promising. One of the main hurdles for emergence of such a technology is the development of a hydroxide-conducting membrane characterized by both high conductivity and low fuel permeability. Plasma treatments can enable to positively tune the main fuel cell membrane requirements. In this work, commercial ADP-Morgane® fluorinated polymer membranes and a new brand of cross-linked poly(aryl-ether) polymer membranes, named AMELI-32®, both containing quaternary ammonium functionalities, have been modified by argon plasma treatment or triallylamine-based plasma deposit. Under the concomitant etching/cross-linking/oxidation effects inherent to the plasma modification, transport properties (ionic exchange capacity, water uptake, ionic conductivity and fuel retention) of membranes have been improved. Consequently, using plasma modified ADP-Morgane® membrane as electrolyte in a solid alkaline fuel cell operating with glycerol as fuel has allowed increasing the maximum power density by a factor 3 when compared to the untreated membrane.

  11. Combustion Performance of a Staged Hybrid Rocket with Boron addition

    Science.gov (United States)

    Lee, D.; Lee, C.

    2018-04-01

    In this paper, the effect of boron on overall system specific impulse was investigated. Additionally, a series of combustion tests was carried out to analyze and evaluate the effect of boron addition on O/F variation and radial temperature profiles. To maintain the hybrid rocket engine advantages, upper limit of boron contents in solid fuel was set to be 10 wt%. The results also suggested that, when adding boron to solid fuel, it helped to provide more uniform radial temperature distribution and also to increase specific impulse by 3.2%.

  12. Combustion of solid alternative fuels in the cement kiln burner

    DEFF Research Database (Denmark)

    Nørskov, Linda Kaare

    In the cement industry there is an increasing environmental and financial motivation for substituting conventional fossil fuels with alternative fuels, being biomass or waste derived fuels. However, the introduction of alternative fuels may influence emissions, cement product quality, process...... stability, and process efficiency. Alternative fuel substitution in the calciner unit has reached close to 100% at many cement plants and to further increase the use of alternative fuels rotary kiln substitution must be enhanced. At present, limited systematic knowledge of the alternative fuel combustion...... properties and the influence on the flame formation is available. In this project a scientific approach to increase the fundamental understanding of alternative fuel conversion in the rotary kiln burner is employed through literature studies, experimental combustion characterisation studies, combustion...

  13. Karl Poggensee - A widely unknown German rocket pioneer - The early years 1930-1934 - A chronology

    Science.gov (United States)

    Rohrwild, Karlheinz

    2017-09-01

    The rediscovered estate of Karl Poggensee allows to reproduce chronologically his rocket tests of the period 1930-1934 almost completely for the first time. Thrilled by the movie ;The Woman in the Moon; for the idea of space travel, he started as a student of Hinderburg-Polytechnikum (IAO), Oldenburg, to build his first solid-fuel rocket, producing his own propellant charges. Being a coming electrical engineer his main goal was not set up new record heights, but to provide his rockets with automatic measuring instruments, camera and parachute release systems. The optimization of this sequence was his main focus.

  14. Lanthanum manganate based cathodes for solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Juhl Joergensen, M.

    2001-07-01

    Composite cathodes for solid oxide fuel cells were investigated using electrochemical impedance spectroscopy and scanning electron microscopy. The aim was to study the oxygen reduction process in the electrode in order to minimise the voltage drop in the cathode. The electrodes contained a composite layer made from lanthanum strontium manganate (LSM) and yttria stabilised zirconia (YSZ) and a layer of pure LSM aimed for current collection. The performance of the composite electrodes was sensitive to microstructure and thickness. Further, the interface between the composite and the current collecting layer proved to affect the performance. In a durability study severe deg-radation of the composite electrodes was found when passing current through the electrode for 2000 hours at 1000 deg. C. This was ascribed to pore formation along the composite interfaces and densification of the composite and current collector microstructure. An evaluation of the measurement approach indicated that impedance spectroscopy is a very sensitive method. This affects the reproducibility, as small undesirable variations in for instance the microstructure from electrode to electrode may change the impedance. At least five processes were found to affect the impedance of LSM/YSZ composite electrodes. Two high frequency processes were ascribed to transport of oxide ions/oxygen intermediates across LSM/YSZ interfaces and through YSZ in the composite. Several competitive elementary reaction steps, which appear as one medium frequency process in the impedance spectra, were observed. A low frequency arc related to gas diffusion limitation in a stagnant gas layer above the composite structure was detected. Finally, an inductive process, assumed to be connected to an activation process involving segregates at the triple phase boundary between electrode, electrolyte and gas phase, was found. (au)

  15. Mathematical modeling of oxygen transport in solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, Ann Mari

    1997-12-31

    This thesis develops mathematical models to describe the electrochemical performance of a solid oxide fuel cell cathode based on electrochemical kinetics and mass transfer. The individual effects of various coupled processes are investigated. A one-dimensional model is developed based on porous electrode theory. Two different mechanisms are investigated for the charge transfer reaction. One of these assumes that intermediately adsorbed oxygen atoms are reduced at the electrode/electrolyte interface, similar to the models proposed for metal electrodes. Simulated polarization curves exhibit limited currents due to depletion of oxygen adsorbates at high cathodic overvoltages. An empirical correlation is confirmed to exist between the limiting current an the oxygen partial pressure, however, a similar correlation often assumed to exist between the measured polarization resistance and the oxygen partial pressure could not be justified. For the other model, oxygen vacancies are assumed to be exchanged directly at the electrode/electrolyte interface. The electrochemical behaviour is improved by reducing the oxygen partial pressure, due to increased vacancy concentration of the electrode material. Simulated polarization curves exhibit Tafel-like slopes in the cathodic direction, which are due to polarization concentration, and not activation polarization in the conventional sense. Anodic limiting currents are predicted due to lack of available free sites for vacancy exchange at the cathode side. The thesis also presents a theoretical treatment of current and potential distributions in simple two-dimensional cell geometries, and a two-dimensional model for a porous electrode-electrolyte system for investigation of the effect of interfacial diffusion of adsorbates along the electrode/electrolyte interface. 172 refs., 60 figs., 11 tabs.

  16. Rocket science

    International Nuclear Information System (INIS)

    Upson Sandra

    2011-01-01

    Expanding across the Solar System will require more than a simple blast off, a range of promising new propulsion technologies are being investigated by ex- NASA shuttle astronaut Chang Diaz. He is developing an alternative to chemical rockets, called VASIMR -Variable Specific Impulse Magnetoplasm Rocket. In 2012 Ad Astra plans to test a prototype, using solar power rather than nuclear, on the International Space Station. Development of this rocket for human space travel is discussed. The nuclear reactor's heat would be converted into electricity in an electric rocket such as VASIMR, and at the peak of nuclear rocket research thrust levels of almost one million newtons were reached.

  17. Life cycle assessment integrated with thermodynamic analysis of bio-fuel options for solid oxide fuel cells.

    Science.gov (United States)

    Lin, Jiefeng; Babbitt, Callie W; Trabold, Thomas A

    2013-01-01

    A methodology that integrates life cycle assessment (LCA) with thermodynamic analysis is developed and applied to evaluate the environmental impacts of producing biofuels from waste biomass, including biodiesel from waste cooking oil, ethanol from corn stover, and compressed natural gas from municipal solid wastes. Solid oxide fuel cell-based auxiliary power units using bio-fuel as the hydrogen precursor enable generation of auxiliary electricity for idling heavy-duty trucks. Thermodynamic analysis is applied to evaluate the fuel conversion efficiency and determine the amount of fuel feedstock needed to generate a unit of electrical power. These inputs feed into an LCA that compares energy consumption and greenhouse gas emissions of different fuel pathways. Results show that compressed natural gas from municipal solid wastes is an optimal bio-fuel option for SOFC-APU applications in New York State. However, this methodology can be regionalized within the U.S. or internationally to account for different fuel feedstock options. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Efficient and Scalable Fabrication of Solid Oxide Fuel Cells via 3D-Printing

    Data.gov (United States)

    National Aeronautics and Space Administration — Although solid oxide fuel cells (SOFCs) are a source of both efficient and clean electricity, the brittle ceramic materials which comprise them are difficult to form...

  19. Novel quasi-symmetric solid oxide fuel cells with enhanced electrochemical performance

    KAUST Repository

    Chen, Yonghong; Cheng, Zhuanxia; Yang, Yang; Gu, Qingwen; Tian, Dong; Lu, Xiaoyong; Yu, Weili; Lin, Bin

    2016-01-01

    Symmetrical solid oxide fuel cell (SSOFC) using same materials as both anode and cathode simultaneously has gained extensively attentions, which can simplify fabrication process, minimize inter-diffusion between components, enhance sulfur and coking

  20. Solid Oxide Fuel Cell Based Upon Colloidal Deposition of Thin Films for Lower Temperature Operation (Preprint)

    National Research Council Canada - National Science Library

    Reitz, T. L; Xiao, H

    2006-01-01

    In order to reduce the operating temperature of solid oxide fuel cells (SOFCs), anode-supported cells incorporating thin film electrolytes in conjunction with anode/electrolyte and cathode/electrolyte interlayers were studied...

  1. Microstructural evolution of nanograin nickel-zirconia cermet anode materials for solid oxide fuel cell applications

    International Nuclear Information System (INIS)

    Nayak, Bibhuti Bhusan

    2012-01-01

    The aim of the study is to study the structure, microstructure, porosity, thermal expansion, electrical conductivity and electrochemical behavior of the anode material thus synthesized in order to find its suitability for solid oxide fuel cell (SOFC) anode application

  2. Annual report and accounts 1980/81. [UK; Solid Fuels Avisory Service; book

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    The work of the Solid Fuel Advisory Service during 1980/81 is described under the headings: sales promotion, market research, service to the public, technical, chimneys and training. The accounts are then presented.

  3. Fuel cells with solid polymer electrolyte and their application on vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Fateev, V.

    1996-04-01

    In Russia, solid polymer electrolyte MF-4-SK has been developed for fuel cells. This electrolyte is based on perfluorinated polymer with functional sulfogroups. Investigations on electrolyte properties and electrocatalysts have been carried out.

  4. Copper based anodes for bio-ethanol fueled low-temperature solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Kondakindi, R.R.; Karan, K. [Queen' s Univ., Kingston, ON (Canada)

    2003-07-01

    Laboratory studies have been conducted to develop a low-temperature solid oxide fuel cell (SOFC) fueled by bio-ethanol. SOFCs are considered to be a potential source for clean and efficient electricity. The use of bio-ethanol to power the SOFC contributes even further to reducing CO{sub 2} emissions. The main barrier towards the development of the proposed SOFC is the identification of a suitable anode catalyst that prevents coking during electro-oxidation of ethanol while yielding good electrical performance. Copper was selected as the catalyst for this study. Composite anodes consisting of copper catalysts and gadolinium-doped ceria (GDC) electrolytes were prepared using screen printing of GDC and copper oxide on dense GDC electrolytes and by wet impregnation of copper nitrate in porous GDC electrolytes followed by calcination and sintering. The electrical conductivity of the prepared anodes was characterized to determine the percolation threshold. Temperature-programmed reduction and the Brunner Emmett Teller (BET) methods were used to quantify the catalyst dispersion and surface area. Electrochemical performance of the single-cell SOFC with a hydrogen-air system was used to assess the catalytic activities. Electrochemical Impedance Spectroscopy was used to probe the electrode kinetics.

  5. Wavelength modulation spectroscopy near 5 μm for carbon monoxide sensing in a high-pressure kerosene-fueled liquid rocket combustor

    Science.gov (United States)

    Lee, Daniel D.; Bendana, Fabio A.; Schumaker, S. Alexander; Spearrin, R. Mitchell

    2018-05-01

    A laser absorption sensor was developed for carbon monoxide (CO) sensing in high-pressure, fuel-rich combustion gases associated with the internal conditions of hydrocarbon-fueled liquid bipropellant rockets. An absorption feature near 4.98 μm, comprised primarily of two rovibrational lines from the P-branch of the fundamental band, was selected to minimize temperature sensitivity and spectral interference with other combustion gas species at the extreme temperatures (> 3000 K) and pressures (> 50 atm) in the combustion chamber environment. A scanned wavelength modulation spectroscopy technique (1 f-normalized 2 f detection) is utilized to infer species concentration from CO absorption, and mitigate the influence of non-absorption transmission losses and noise associated with the harsh sooting combustor environment. To implement the sensing strategy, a continuous-wave distributed-feedback (DFB) quantum cascade laser (QCL) was coupled to a hollow-core optical fiber for remote mid-infrared light delivery to the test article, with high-bandwidth light detection by a direct-mounted photovoltaic detector. The method was demonstrated to measure time-resolved CO mole fraction over a range of oxidizer-to-fuel ratios and pressures (20-70 atm) in a single-element-injector RP-2-GOx rocket combustor.

  6. Internal shorting and fuel loss of a low temperature solid oxide fuel cell with SDC electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xinge; Robertson, Mark; Deces-Petit, Cyrille; Qu, Wei; Kesler, Olivera; Maric, Radenka; Ghosh, Dave [Institute for Fuel Cell Innovation, National Research Council Canada, 4250 Wesbrook Mall, Vancouver, BC V6T 1W5 (Canada)

    2007-02-10

    A solid oxide fuel cell with Sm{sub 0.2}Ce{sub 0.8}O{sub 1.9} (SDC) electrolyte of 10 {mu}m in thickness and Ni-SDC anode of 15 {mu}m in thickness on a 0.8 mm thick Ni-YSZ cermet substrate was fabricated by tape casting, screen printing and co-firing. A composite cathode, 75 wt.% Sm{sub 0.5}Sr{sub 0.5}CoO{sub 3} (SSCo) + 25 wt.% SDC, approximately 50 {mu}m in thickness, was printed on the co-fired half-cell, and sintered at 950 C. The cell showed a high electrochemical performance at temperatures ranging from 500 to 650 C. Peak power density of 545 mW cm{sup -2} at 600 C was obtained. However, the cell exhibited severe internal shorting due to the mixed conductivity of the SDC electrolyte. Both the amount of water collected from the anode outlet and the open circuit voltage (OCV) indicated that the internal shorting current could reach 0.85 A cm{sup -2} or more at 600 C. Zr content inclusions were found at the surface and in the cross-section of the SDC electrolyte, which could be one of the reasons for reduced OCV and oxygen ionic conductivity. Fuel loss due to internal shorting of the thin SDC electrolyte cell becomes a significant concern when it is used in applications requiring high fuel utilization and electrical efficiency. (author)

  7. Thermodynamic analysis of Direct Urea Solid Oxide Fuel Cell in combined heat and power applications

    Science.gov (United States)

    Abraham, F.; Dincer, I.

    2015-12-01

    This paper presents a comprehensive steady state modelling and thermodynamic analysis of Direct Urea Solid Oxide Fuel Cell integrated with Gas Turbine power cycle (DU-SOFC/GT). The use of urea as direct fuel mitigates public health and safety risks associated with the use of hydrogen and ammonia. The integration scheme in this study covers both oxygen ion-conducting solid oxide fuel cells (SOFC-O) and hydrogen proton-conducting solid oxide fuel cells (SOFC-H). Parametric case studies are carried out to investigate the effects of design and operating parameters on the overall performance of the system. The results reveal that the fuel cell exhibited the highest level of exergy destruction among other system components. Furthermore, the SOFC-O based system offers better overall performance than that with the SOFC-H option mainly due to the detrimental reverse water-gas shift reaction at the SOFC anode as well as the unique configuration of the system.

  8. Advanced circulating fluidised bed technology (CFB) for large-scale solid biomass fuel firing power plants

    Energy Technology Data Exchange (ETDEWEB)

    Jaentti, Timo; Zabetta, Edgardo Coda; Nuortimo, Kalle [Foster Wheeler Energia Oy, Varkaus (Finland)

    2013-04-01

    Worldwide the nations are taking initiatives to counteract global warming by reducing their greenhouse gas emissions. Efforts to increase boiler efficiency and the use of biomass and other solid renewable fuels are well in line with these objectives. Circulating fluidised bed boilers (CFB) are ideal for efficient power generation, capable to fire a broad variety of solid biomass fuels from small CHP plants to large utility power plants. Relevant boiler references in commercial operation are made for Finland and Poland.

  9. Airflow Obstruction and Use of Solid Fuels for Cooking or Heating: BOLD Results.

    Science.gov (United States)

    Amaral, André F S; Patel, Jaymini; Kato, Bernet S; Obaseki, Daniel O; Lawin, Hervé; Tan, Wan C; Juvekar, Sanjay K; Harrabi, Imed; Studnicka, Michael; Wouters, Emiel F M; Loh, Li-Cher; Bateman, Eric D; Mortimer, Kevin; Buist, A Sonia; Burney, Peter G J

    2017-09-12

    Evidence supporting the association of COPD or airflow obstruction with use of solid fuels is conflicting and inconsistent. To assess the association of airflow obstruction with self-reported use of solid fuels for cooking or heating. We analysed 18,554 adults from the BOLD study, who had provided acceptable post-bronchodilator spirometry measurements and information on use of solid fuels. The association of airflow obstruction with use of solid fuels for cooking or heating was assessed by sex, within each site, using regression analysis. Estimates were stratified by national income and meta-analysed. We carried out similar analyses for spirometric restriction, chronic cough and chronic phlegm. We found no association between airflow obstruction and use of solid fuels for cooking or heating (ORmen=1.20, 95%CI 0.94-1.53; ORwomen=0.88, 95%CI 0.67-1.15). This was true for low/middle and high income sites. Among never smokers there was also no evidence of an association of airflow obstruction with use of solid fuels (ORmen=1.00, 95%CI 0.57-1.76; ORwomen=1.00, 95%CI 0.76-1.32). Overall, we found no association of spirometric restriction, chronic cough or chronic phlegm with the use of solid fuels. However, we found that chronic phlegm was more likely to be reported among female never smokers and those who had been exposed for ≥20 years. Airflow obstruction assessed from post-bronchodilator spirometry was not associated with use of solid fuels for cooking or heating.

  10. Robotic Manufacturing of 18-ft (5.5m) Diameter Cryogenic Fuel Tank Dome Assemblies for the NASA Ares I Rocket

    Science.gov (United States)

    Jones, Ronald E.; Carter, Robert W.

    2012-01-01

    The Ares I rocket was the first launch vehicle scheduled for manufacture under the National Aeronautic and Space Administration's Constellation program. A series of full-scale Ares I development articles were constructed on the Robotic Weld Tool at the NASA George C. Marshall Space Flight Center in Huntsville, Alabama. The Robotic Weld Tool is a 100 ton, 7- axis, robotic manufacturing system capable of machining and friction stir welding large-scale space hardware. This paper will focus on the friction stir welding of 18-ft (5.5m) diameter cryogenic fuel tank components; specifically, the liquid hydrogen forward dome and two common bulkhead manufacturing development articles.

  11. Simulation of reactive polydisperse sprays strongly coupled to unsteady flows in solid rocket motors: Efficient strategy using Eulerian Multi-Fluid methods

    Science.gov (United States)

    Sibra, A.; Dupays, J.; Murrone, A.; Laurent, F.; Massot, M.

    2017-06-01

    In this paper, we tackle the issue of the accurate simulation of evaporating and reactive polydisperse sprays strongly coupled to unsteady gaseous flows. In solid propulsion, aluminum particles are included in the propellant to improve the global performances but the distributed combustion of these droplets in the chamber is suspected to be a driving mechanism of hydrodynamic and acoustic instabilities. The faithful prediction of two-phase interactions is a determining step for future solid rocket motor optimization. When looking at saving computational ressources as required for industrial applications, performing reliable simulations of two-phase flow instabilities appears as a challenge for both modeling and scientific computing. The size polydispersity, which conditions the droplet dynamics, is a key parameter that has to be accounted for. For moderately dense sprays, a kinetic approach based on a statistical point of view is particularly appropriate. The spray is described by a number density function and its evolution follows a Williams-Boltzmann transport equation. To solve it, we use Eulerian Multi-Fluid methods, based on a continuous discretization of the size phase space into sections, which offer an accurate treatment of the polydispersion. The objective of this paper is threefold: first to derive a new Two Size Moment Multi-Fluid model that is able to tackle evaporating polydisperse sprays at low cost while accurately describing the main driving mechanisms, second to develop a dedicated evaporation scheme to treat simultaneously mass, moment and energy exchanges with the gas and between the sections. Finally, to design a time splitting operator strategy respecting both reactive two-phase flow physics and cost/accuracy ratio required for industrial computations. Using a research code, we provide 0D validations of the new scheme before assessing the splitting technique's ability on a reference two-phase flow acoustic case. Implemented in the industrial

  12. Solid oxide fuel cells for transportation: A clean, efficient alternative for propulsion

    International Nuclear Information System (INIS)

    Kumar, R.; Krumpelt, M.; Myles, K.M.

    1993-01-01

    Fuel cells show great promise for providing clean and efficient transportation power. Of the fuel cell propulsion systems under investigation, the solid oxide fuel cell (SOFC) is particularly attractive for heavy duty transportation applications that have a relatively long duty cycle, such as locomotives, trucks, and barges. Advantages of the SOFC include a simple, compact system configuration; inherent fuel flexibility for hydrocarbon and alternative fuels; and minimal water management. The specific advantages of the SOFC for powering a railroad locomotive are examined. Feasibility, practicality, and safety concerns regarding SOFCs in transportation applications are discussed, as am the major R ampersand D issues

  13. Fuzzy Logic Based Controller for a Grid-Connected Solid Oxide Fuel Cell Power Plant.

    Science.gov (United States)

    Chatterjee, Kalyan; Shankar, Ravi; Kumar, Amit

    2014-10-01

    This paper describes a mathematical model of a solid oxide fuel cell (SOFC) power plant integrated in a multimachine power system. The utilization factor of a fuel stack maintains steady state by tuning the fuel valve in the fuel processor at a rate proportional to a current drawn from the fuel stack. A suitable fuzzy logic control is used for the overall system, its objective being controlling the current drawn by the power conditioning unit and meet a desirable output power demand. The proposed control scheme is verified through computer simulations.

  14. Comparison of coal/solid recovered fuel (SRF) with coal/refuse derived fuel (RDF) in a fluidised bed reactor

    International Nuclear Information System (INIS)

    Wagland, S.T.; Kilgallon, P.; Coveney, R.; Garg, A.; Smith, R.; Longhurst, P.J.; Pollard, S.J.T.; Simms, N.

    2011-01-01

    An experimental study was undertaken to compare the differences between municipal solid waste (MSW) derived solid recovered fuel (SRF) (complying with CEN standards) and refuse derived fuel (RDF). Both fuels were co-combusted with coal in a 50 kW fluidised bed combustor and the metal emissions were compared. Synthetic SRF was prepared in the laboratory by grinding major constituents of MSW such as paper, plastic, textile and wood. RDF was obtained from a local mechanical treatment plant. Heavy metal emissions in flue gas and ash samples from the (coal + 10% SRF) fuel mixture were found to be within the acceptable range and were generally lower than that obtained for coal + 10% RDF fuel mixture. The relative distribution of heavy metals in ash components and the flue gas stream shows the presence of a large fraction (up to 98%) of most of the metals in the ash (except Hg and As). Thermo-gravimetric (TG) analysis of SRF constituents was performed to understand the behaviour of fuel mixtures in the absence and presence of air. The results obtained from the experimental study will enhance the confidence of fuel users towards using MSW-derived SRF as an alternative fuel.

  15. An afterburner-powered methane/steam reformer for a solid oxide fuel cells application

    Science.gov (United States)

    Mozdzierz, Marcin; Chalusiak, Maciej; Kimijima, Shinji; Szmyd, Janusz S.; Brus, Grzegorz

    2018-04-01

    Solid oxide fuel cell (SOFC) systems can be fueled by natural gas when the reforming reaction is conducted in a stack. Due to its maturity and safety, indirect internal reforming is usually used. A strong endothermic methane/steam reforming process needs a large amount of heat, and it is convenient to provide thermal energy by burning the remainders of fuel from a cell. In this work, the mathematical model of afterburner-powered methane/steam reformer is proposed. To analyze the effect of a fuel composition on SOFC performance, the zero-dimensional model of a fuel cell connected with a reformer is formulated. It is shown that the highest efficiency of a solid oxide fuel cell is achieved when the steam-to-methane ratio at the reforming reactor inlet is high.

  16. The history, genotoxicity, and carcinogenicity of carbon-based fuels and their emissions. Part 2: solid fuels.

    Science.gov (United States)

    Claxton, Larry D

    2014-01-01

    The combustion of solid fuels (like wood, animal dung, and coal) usually involves elevated temperatures and altered pressures and genotoxicants (e.g., PAHs) are likely to form. These substances are carcinogenic in experimental animals, and epidemiological studies implicate these fuels (especially their emissions) as carcinogens in man. Globally, ∼50% of all households and ∼90% of all rural households use solid fuels for cooking or heating and these fuels often are burnt in simple stoves with very incomplete combustion. Exposed women and children often exhibit low birth weight, increased infant and perinatal mortality, head and neck cancer, and lung cancer although few studies have measured exposure directly. Today, households that cannot meet the expense of fuels like kerosene, liquefied petroleum gas, and electricity resort to collecting wood, agricultural residue, and animal dung to use as household fuels. In the more developed countries, solid fuels are often used for electric power generation providing more than half of the electricity generated in the United States. The world's coal reserves, which equal approximately one exagram, equal ∼1 trillion barrels of crude oil (comparable to all the world's known oil reserves) and could last for 600 years. Studies show that the PAHs that are identified in solid fuel emissions react with NO2 to form direct-acting mutagens. In summary, many of the measured genotoxicants found in both the indoor and electricity-generating combustors are the same; therefore, the severity of the health effects vary with exposure and with the health status of the exposed population. Copyright © 2014. Published by Elsevier B.V.

  17. Strontium Titanate-based Composite Anodes for Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Blennow Tullmar, Peter; Kammer Hansen, Kent; Wallenberg, L.R.

    2008-01-01

    Surfactant-assisted infiltration of Gd-doped ceria (CGO) in Nb-doped SrTiO3 (STN) was investigated as a potential fuel electrode for solid oxide fuel cells (SOFC). An electronically conductive backbone structure of STN was first fabricated at high temperatures and then combined with the mixed con...

  18. On-line determination of the calorific value of solid fuels

    NARCIS (Netherlands)

    Kessel, L.B.M. van; Arendsen, A.R.J.; Brem, G.

    2004-01-01

    In thermal processes with highly inhomogeneous fuels it is desirable to know real time fuel characteristics. In the case of municipal solid waste combustion (MSWC) it was up till now not possible to determine the calorific value of the waste on-line with a high accuracy. In this paper, a new method

  19. Environmental protection and processes for burning solid fuel. Zashchita okruzhayushchey sredy i protsessy goreniya tverdovo topliva

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    The anthology's materials are devoted to studying the mechanism of formation of harmful emissions during burning of solid fuels, methods of suppressing processes of formation of nitrogen oxide in boiler devices, and processes of combustion to create power plants with minimal emissions of NO /SUB x/ and SO /SUB x/ and maximum use of organic and mineral components of the fuel.

  20. Three-phase boundary length in solid-oxide fuel cells: A mathematical model

    Science.gov (United States)

    Janardhanan, Vinod M.; Heuveline, Vincent; Deutschmann, Olaf

    A mathematical model to calculate the volume specific three-phase boundary length in the porous composite electrodes of solid-oxide fuel cell is presented. The model is exclusively based on geometrical considerations accounting for porosity, particle diameter, particle size distribution, and solids phase distribution. Results are presented for uniform particle size distribution as well as for non-uniform particle size distribution.

  1. Pressurized solid oxide fuel cell integral air accumular containment

    Science.gov (United States)

    Gillett, James E.; Zafred, Paolo R.; Basel, Richard A.

    2004-02-10

    A fuel cell generator apparatus contains at least one fuel cell subassembly module in a module housing, where the housing is surrounded by a pressure vessel such that there is an air accumulator space, where the apparatus is associated with an air compressor of a turbine/generator/air compressor system, where pressurized air from the compressor passes into the space and occupies the space and then flows to the fuel cells in the subassembly module, where the air accumulation space provides an accumulator to control any unreacted fuel gas that might flow from the module.

  2. Pulse combustors for unpulverized solid fuels; Combustor pulsante para solidos nao pulverizados

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Marco Aurelio; Carvalho Junior, Joao Andrade de [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil)

    1988-12-31

    This work presents results of performance evaluation of an experimental pulsating combustor developed to burn unpulverized solid fuels. The fuels tested were sized wood blocks and coal lumps. The results for coal show a clear maximum combustion efficiency as a function of fuel loading within the combustor. For an excess of air of 10%, a maximum combustion efficiency of 94% was obtained. (author) 38 refs., 10 figs., 2 tabs.

  3. Study of catalysis for solid oxide fuel cells and direct methanol fuel cells

    Science.gov (United States)

    Jiang, Xirong

    Fuel cells offer the enticing promise of cleaner electricity with lower environmental impact than traditional energy conversion technologies. Driven by the interest in power sources for portable electronics, and distributed generation and automotive propulsion markets, active development efforts in the technologies of both solid oxide fuel cell (SOFC) and direct methanol fuel cell (DMFC) devices have achieved significant progress. However, current catalysts for fuel cells are either of low catalytic activity or extremely expensive, presenting a key barrier toward the widespread commercialization of fuel cell devices. In this thesis work, atomic layer deposition (ALD), a novel thin film deposition technique, was employed to apply catalytic Pt to SOFC, and investigate both Pt skin catalysts and Pt-Ru catalysts for methanol oxidation, a very important reaction for DMFC, to increase the activity and utilization levels of the catalysts while simultaneously reducing the catalyst loading. For SOFCs, we explored the use of ALD for the fabrication of electrode components, including an ultra-thin Pt film for use as the electrocatalyst, and a Pt mesh structure for a current collector for SOFCs, aiming for precise control over the catalyst loading and catalyst geometry, and enhancement in the current collect efficiency. We choose Pt since it has high chemical stability and excellent catalytic activity for the O2 reduction reaction and the H2 oxidation reaction even at low operating temperatures. Working SOFC fuel cells were fabricated with ALD-deposited Pt thin films as an electrode/catalyst layer. The measured fuel cell performance reveals that comparable peak power densities were achieved for ALD-deposited Pt anodes with only one-fifth of the Pt loading relative to a DC-sputtered counterpart. In addition to the continuous electrocatalyst layer, a micro-patterned Pt structure was developed via the technique of area selective ALD. By coating yttria-stabilized zirconia, a

  4. Optimization of combustion process for radiation-treated solid fuels in dust state

    International Nuclear Information System (INIS)

    Askarova, A.S.; Bajdullaeva, G.E.

    1997-01-01

    Computation experiment on combustion of solid radiation-treated fuel in burning chamber of boiler at Pavlodar thermal electric plant is carried out. Velocity, temperature distribution and concentration of combustion products by height of chamber are received. Analysis of received results shows that radiation treatment of fuels exerts substantial effect on egress parameters of thermal electric plant. It is shown, that radiation treatment allows to improve effectiveness of boiler device and reduce of harmful substances discharge in atmosphere. Results of conducted numerical experiments allow to create complete methods of solid fuel combustion with high moisture and ashiness

  5. New Cathode Materials for Intermediate Temperature Solid Oxide Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Allan J. Jacobson

    2006-09-30

    the perovskite compositions that were being investigated at PNNL, in order to assess the relative importance of the intrinsic properties such as oxygen ion diffusion and surface exchange rates as predictors of performance in cell tests. We then used these measurements to select new materials for scaled up synthesis and performance evaluation in single cell tests. The results of the single cell tests than provided feedback to the materials synthesis and selection steps. In this summary, the following studies are reported: (1) Synthesis, characterization, and DC conductivity measurements of the P1 compositions La{sub 0.8}Sr{sub 0.2}FeO{sub 3-x} and La{sub 0.7}Sr{sub 0.3}FeO{sub 3-x} were completed. A combinational approach for preparing a range P1 (La,Sr)FeO{sub 3} compositions as thin films was investigated. Synthesis and heat treatment of amorphous SrFeO{sub 3-x} and LaFeO{sub 3-x} films prepared by pulsed laser deposition are described. (2) Oxygen transport properties of K1 compositions La{sub x}Pr{sub 2-x}NiO{sub 4+d} (x =2.0, 1.9, 1.2, 1.0 and 0) measured by electrical conductivity relaxation are presented in this report. Area specific resistances determined by ac impedance measurements for La{sub 2}NiO{sub 4+{delta}} and Pr{sub 2}NiO{sub 4+{delta}} on CGO are encouraging and suggest that further optimization of the electrode microstructure will enable the target to be reached. (3) The oxygen exchange kinetics of the oxygen deficient double perovskite LnBaCo{sub 2}O{sub 5.5+{delta}} (Ln=Pr and Nd) were determined by electrical conductivity relaxation. The high electronic conductivity and rapid diffusion and surface exchange kinetics of PBCO suggest its application as cathode material in intermediate temperature solid oxide fuel cells. The first complete cell measurements were performed on Ni/CGO/CGO/PBCO/CGO cells. (4) The oxygen exchange kinetics of highly epitaxial thin films of PrBaCo{sub 2}O{sub 5.5+{delta}} (PBCO) has been determined by electrical conductivity

  6. Theodore von Karman - Rocket Scientist

    Indian Academy of Sciences (India)

    seminal contributions to several areas of fluid and solid mechanics, as the first head of ... nent position in Aeronautics research, as a pioneer of rocket science in America ... toral work, however, was on the theory of buckling of large structures.

  7. Feasibility of using neutron radiography to inspect the Space Shuttle solid rocket booster aft skirt, forward skirt and frustum. Part 1: Summary report

    Science.gov (United States)

    Barton, J. P.; Bader, J. W.; Brenizer, J. S.; Hosticka, B.

    1992-01-01

    The space shuttle's solid rocket boosters (SRB) include components made primarily of aluminum that are parachuted back for retrieval from the ocean and refurbished for repeated usage. Nondestructive inspection methods used on these aging parts to reduce the risk of unforeseen problems include x-ray, ultrasonics, and eddy current. Neutron radiography tests on segments of an SRB component show that entrapped moisture and naturally occurring aluminum corrosion can be revealed by neutron radiography even if present in only small amounts. Voids in sealant can also be evaluated. Three alternatives are suggested to follow-up this study: (1) take an SRB component to an existing neutron radiography system; (2) take an existing mobile neutron radiography system to the NASA site; or (3) plan a dedicated system custom designed for NASA applications.

  8. Potential electrode materials for symmetrical Solid Oxide Fuel Cells

    Directory of Open Access Journals (Sweden)

    Ruiz Morales, J. C.

    2008-08-01

    Full Text Available Chromites, titanates and Pt-YSZ-CeO2 cermets have been investigated as potential electrode materials for an alternative concept of Solid Oxide Fuel Cell (SOFC, the symmetrical SOFCs (SFC. In this configuration, the same electrode material is used simultaneously as anode and cathode. Interconnector materials, such as chromites, could be considered as potential SFC electrodes, at least under pure hydrogen-fed at relatively high temperatures, as they do not exhibit significant catalytic activity towards hydrocarbon oxidation. This may be overcome by partially substituting Cr in the perovskite B-sites by other transition metal cations such as Mn. La0.75Sr0.25Cr0.5Mn0.5O3-δ (LSCM is a good candidate for such SFCs, rendering fuel cell performances in excess of 500 and 300mW/cm2 using pure H2 and CH4 as fuel, at 950 oC. Similarly, typical n-type electronic conductors traditionally regarded as anode materials, such as strontium titanates, may also operate under oxidising conditions as cathodes by substituting some Ti content for Fe to introduce p-type conductivity. Preliminary electrochemical experiments on La4Sr8Ti12-xFexO38-δ-based SFCs show that they perform reasonably well under humidified H2, at high temperatures. A third group of materials is the support material of any typical cermet anode, i.e. YSZ, CeO2 plus a current collector. It has been found that this combination could be optimised to operate as SFC electrodes, rendering performances of 400mW/cm2 under humidified pure H2 at 950oC.

    Cromitas, titanatos y cermets de Pt-YSZ-CeO2 han sido investigados como potenciales materiales de electrodo para un concepto alternativo de Pilas de Combustible de Óxidos Sólidos (SOFC, las pilas SOFC simétricas (SFC. En

  9. A QSAR/QSTR Study on the Environmental Health Impact by the Rocket Fuel 1,1-Dimethyl Hydrazine and its Transformation Products

    Directory of Open Access Journals (Sweden)

    Lars Carlsen

    2008-01-01

    Full Text Available QSAR/QSTR modelling constitutes an attractive approach to preliminary assessment of the impact on environmental health by a primary pollutant and the suite of transformation products that may be persistent in and toxic to the environment. The present paper studies the impact on environmental health by residuals of the rocket fuel 1,1-dimethyl hydrazine (heptyl and its transformation products. The transformation products, comprising a variety of nitrogen containing compounds are suggested all to possess a significant migration potential. In all cases the compounds were found being rapidly biodegradable. However, unexpected low microbial activity may cause significant changes. None of the studied compounds appear to be bioaccumulating. Apart from substances with an intact hydrazine structure or hydrazone structure the transformation products in general display rather low environmental toxicities. Thus, it is concluded that apparently further attention should be given to tri- and tetramethyl hydrazine and 1-formyl 2,2-dimethyl hydrazine as well as to the hydrazones of formaldehyde and acetaldehyde as these five compounds may contribute to the overall environmental toxicity of residual rocket fuel and its transformation products.

  10. On the importance of reduced scale Ariane 5 P230 solid rocket motor models in the comprehension and prevention of thrust oscillations

    Science.gov (United States)

    Hijlkema, J.; Prévost, M.; Casalis, G.

    2011-09-01

    Down-scaled solid propellant motors are a valuable tool in the study of thrust oscillations and the underlying, vortex-shedding-induced, pressure instabilities. These fluctuations, observed in large segmented solid rocket motors such as the Ariane 5 P230, impose a serious constraint on both structure and payload. This paper contains a survey of the numerous configurations tested at ONERA over the last 20 years. Presented are the phenomena searched to reproduce and the successes and failures of the different approaches tried. The results of over 130 experiments have contributed to numerous studies aimed at understanding the complicated physics behind this thorny problem, in order to pave the way to pressure instability reduction measures. Slowly but surely our understanding of what makes large segmented solid boosters exhibit this type of instabilities will lead to realistic modifications that will allow for a reduction of pressure oscillations. A "quieter" launcher will be an important advantage in an ever more competitive market, giving a easier ride to payload and designers alike.

  11. Thermal Analysis of Solid Fuels in an Inert Atmosphere

    Science.gov (United States)

    Kijo-Kleczkowska, Agnieszka; Szumera, Magdalena; Środa, Katarzyna

    2017-12-01

    The paper takes the analysis of thermal studies of different types of fuels. It allowed diversification of fuels depending on their composition and origin. Consideration of coal, biomass and waste (coal mule, sewage sludge) as fuel is nowadays an important aspect of energy in our country. It should be emphasized that Poland power engineering is based up to 95% on coal - the primary fuel. Mining industry, forced to deliver power engineering more and better fuel, must however, use a deeper cleaning of coal. This results in a continuous increase waste in the form of mule flotation. The best method of disposing these mule is combustion and co-combustion with other fuels. On the other hand, commonly increasing awareness state of the environment and the need to reduce CO2 emissions energy industry have committed to implement alternative solutions in order to gain power, through, i.a.: development technologies use of biomass, which is one of the most promising renewable energy sources in Poland. The paper presents the results of research TG-DTA fuels made in an inert atmosphere.

  12. Application of the monolithic solid oxide fuel cell to space power systems

    International Nuclear Information System (INIS)

    Myles, K.M.; Bhattacharyya, S.K.

    1991-01-01

    The monolithic solid-oxide fuel cell (MSOFC) is a promising electrochemical power generation device that is currently under development at Argonne National Laboratory. The extremely high power density of the MSOFC leads to MSOFC systems that have sufficiently high energy densities that they are excellent candidates for a number of space missions. The fuel cell can also be operated in reverse, if it can be coupled to an external power source, to regenerate the fuel and oxidant from the water product. This feature further enhances the potential mission applications of the MSOFC. In this paper, the current status of the fuel cell development is presented---the focus being on fabrication and currently achievable performance. In addition, a specific example of a space power system, featuring a liquid metal cooled fast spectrum nuclear reactor and a monolithic solid oxide fuel cell, is presented to demonstrate the features of an integrated system

  13. Application of the monolithic solid oxide fuel cell to space power systems

    Science.gov (United States)

    Myles, Kevin M.; Bhattacharyya, Samit K.

    1991-01-01

    The monolithic solid-oxide fuel cell (MSOFC) is a promising electrochemical power generation device that is currently under development at Argonne National Laboratory. The extremely high power density of the MSOFC leads to MSOFC systems that have sufficiently high energy densities that they are excellent candidates for a number of space missions. The fuel cell can also be operated in reverse, if it can be coupled to an external power source, to regenerate the fuel and oxidant from the water product. This feature further enhances the potential mission applications of the MSOFC. In this paper, the current status of the fuel cell development is presented—the focus being on fabrication and currently achievable performance. In addition, a specific example of a space power system, featuring a liquid metal cooled fast spectrum nuclear reactor and a monolithic solid oxide fuel cell, is presented to demonstrate the features of an integrated system.

  14. A research on polyether glycol replaced APCP rocket propellant

    Science.gov (United States)

    Lou, Tianyou; Bao, Chun Jia; Wang, Yiyang

    2017-08-01

    Ammonium perchlorate composite propellant (APCP) is a modern solid rocket propellant used in rocket vehicles. It differs from many traditional solid rocket propellants by the nature of how it is processed. APCP is cast into shape, as opposed to powder pressing it with black powder. This provides manufacturing regularity and repeatability, which are necessary requirements for use in the aerospace industry. For traditional APCP, ingredients normally used are ammonium peroxide, aluminum, Hydroxyl-terminated polybutadiene(HTPB), curing agency and other additives, the greatest disadvantage is that the fuel is too expensive. According to the price we collected in our country, a single kilogram of this fuel will cost 200 Yuan, which is about 35 dollars, for a fan who may use tons of the fuel in a single year, it definitely is a great deal of money. For this reason, we invented a new kind of APCP fuel. Changing adhesive agency from cross-linked htpb to cross linked polyether glycol gives a similar specific thrust, density and mechanical property while costs a lower price.

  15. Thermodynamic Analysis of an Integrated Solid Oxide Fuel Cell Cycle with a Rankine Cycle

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2010-01-01

    Hybrid systems consisting of Solid Oxide Fuel Cells (SOFC) on the top of a Steam Turbine (ST) are investigated. The plants are fired by natural gas (NG). A desulfurization reactor removes the sulfur content in the fuel while a pre-reformer breaks down the heavier hydrocarbons. The pre-treated fuel......% are achieved which is considerably higher than the conventional Combined Cycles (CC). Both ASR (Adiabatic Steam Reformer) and CPO (Catalytic Partial Oxidation) fuel pre-reformer reactors are considered in this investigation....

  16. Fuel Cell Power Plant Initiative. Volume 1; Solid Oxide Fuel Cell/Logistics Fuel Processor 27 kWe Power System Demonstration for ARPA

    Science.gov (United States)

    Veyo, S.E.

    1997-01-01

    This report describes the successful testing of a 27 kWe Solid Oxide Fuel Cell (SOFC) generator fueled by natural gas and/or a fuel gas produced by a brassboard logistics fuel preprocessor (LFP). The test period began on May 24, 1995 and ended on February 26, 1996 with the successful completion of all program requirements and objectives. During this time period, this power system produced 118.2 MWh of electric power. No degradation of the generator's performance was measured after 5582 accumulated hours of operation on these fuels: local natural gas - 3261 hours, jet fuel reformate gas - 766 hours, and diesel fuel reformate gas - 1555 hours. This SOFC generator was thermally cycled from full operating temperature to room temperature and back to operating temperature six times, because of failures of support system components and the occasional loss of test site power, without measurable cell degradation. Numerous outages of the LFP did not interrupt the generator's operation because the fuel control system quickly switched to local natural gas when an alarm indicated that the LFP reformate fuel supply had been interrupted. The report presents the measured electrical performance of the generator on all three fuel types and notes the small differences due to fuel type. Operational difficulties due to component failures are well documented even though they did not affect the overall excellent performance of this SOFC power generator. The final two appendices describe in detail the LFP design and the operating history of the tested brassboard LFP.

  17. The study of flow and proton exchange interactions in the cylindrical solid oxide fuel cell

    International Nuclear Information System (INIS)

    Saievar-Iranizad, E.; Malekifar, A.

    2002-01-01

    The solid oxide fuel cell operates at high temperature of about 1000 deg C. In this temperature, some known materials such as Ni, ... which is abundant in the nature, can be used as a catalyst in the electrodes. The electrolytes of such cell solid oxide fuel cell can be made through non-porous solid ceramics such as Zircon's (ZrO 2 ). It can be stabilized using a doped Yttrium oxide. The importance of Yttria-stabilised Zirconia at high temperature belongs to the transport of oxygen ions through the electrolyte. Oxygen using in the hot cathode side causes a considerable reduction in the concentration of oxygen molecules. The oxygen ions exchange through the electrolyte relates to the molecular oxygen concentration gradient between the anode and cathode. Applying fuels such as hydrogen or natural gas in the anode and its chemical reaction with oxygen ions transfer from cathode through the electrolyte, produce electricity, water and heat. To study the ion exchange and its interaction into solid oxide fuel cell, a mathematical model had been considered in this article. This model simulates and illustrates the interaction, diffusion and oxygen ions exchange into fuel cell. The electrical power of fuel cell due to the ion exchange can be obtained using a simulation method. The ion exchange simulation, diffusion of molecules, their interactions and system development through the mathematical model has been discussed in this paper

  18. Copper-substituted perovskite compositions for solid oxide fuel cell cathodes and oxygen reduction electrodes in other electrochemical devices

    Science.gov (United States)

    Rieke, Peter C [Pasco, WA; Coffey, Gregory W [Richland, WA; Pederson, Larry R [Kennewick, WA; Marina, Olga A [Richland, WA; Hardy, John S [Richland, WA; Singh, Prabhaker [Richland, WA; Thomsen, Edwin C [Richland, WA

    2010-07-20

    The present invention provides novel compositions that find advantageous use in making electrodes for electrochemical cells. Also provided are electrochemical devices that include active oxygen reduction electrodes, such as solid oxide fuel cells, sensors, pumps and the like. The compositions comprises a copper-substituted ferrite perovskite material. The invention also provides novel methods for making and using the electrode compositions and solid oxide fuel cells and solid oxide fuel cell assemblies having cathodes comprising the compositions.

  19. Municipal solid waste combustion: Fuel testing and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Bushnell, D.J.; Canova, J.H.; Dadkhah-Nikoo, A.

    1990-10-01

    The objective of this study is to screen and characterize potential biomass fuels from waste streams. This will be accomplished by determining the types of pollutants produced while burning selected municipal waste, i.e., commercial mixed waste paper residential (curbside) mixed waste paper, and refuse derived fuel. These materials will be fired alone and in combination with wood, equal parts by weight. The data from these experiments could be utilized to size pollution control equipment required to meet emission standards. This document provides detailed descriptions of the testing methods and evaluation procedures used in the combustion testing and characterization project. The fuel samples will be examined thoroughly from the raw form to the exhaust emissions produced during the combustion test of a densified sample.

  20. Hybrids - Best of both worlds. [liquid and solid propellants mated for safe reliable and low cost launch vehicles

    Science.gov (United States)

    Goldberg, Ben E.; Wiley, Dan R.

    1991-01-01

    An overview is presented of hybrid rocket propulsion systems whereby combining solids and liquids for launch vehicles could produce a safe, reliable, and low-cost product. The primary subsystems of a hybrid system consist of the oxidizer tank and feed system, an injector system, a solid fuel grain enclosed in a pressure vessel case, a mixing chamber, and a nozzle. The hybrid rocket has an inert grain, which reduces costs of development, transportation, manufacturing, and launch by avoiding many safety measures that must be taken when operating with solids. Other than their use in launch vehicles, hybrids are excellent for simulating the exhaust of solid rocket motors for material development.

  1. Viscoelastic response of HTPB based solid fuel to horizontal and vertical storage slumping conditions and it's affect on service life

    International Nuclear Information System (INIS)

    Nawaz, Q.; Nizam, F.

    2011-01-01

    Frequent use of solid fuels as thrust generating energy source in modern day space vehicle systems has created a need to assess their serviceability for long term storage under various conditions. Solid fuel grain, the most important part of any solid fuel system, responds visco elastically to any loading condition. For the assessment of the service life of any solid fuel system, the solid fuel grain has to be structurally evaluated in applied storage conditions. Structural integrity of the grain is exceptionally significant to guarantee the successful operation of the solid fuel system. In this work, numerical simulations have been performed to assess the mechanical stresses and strains induced in an HTPB based solid fuel grain during service life employing ABAQUS standard FEA software using 4-node bilinear quadrilateral elements. For finite element analysis (FEA), typical 2-D and p/nth axisymmetric section of 5-point (n) star grain geometry is considered. Mechanical loads include the horizontal or vertical 1-g (solid fuel weight) storage condition. The simulation results are compared with the analytical results for the same grain geometry. Analytically measured slump deflections in grain segment at various storage times have been found in good relation with the FEA based simulation results. This proves the validity of the procedure adopted and is helpful in assessment of the service life of solid fuel systems. (author)

  2. Thermodynamic analysis of solid oxide fuel cell gas turbine systems operating with various biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Patel, H.C.; Woudstra, T.; Aravind, P.V. [Process and Energy Laboratory, Delft University of Technology, Section Energy Technology, Leeghwaterstraat 44, 2628 CA Delft (Netherlands)

    2012-12-15

    Solid oxide fuel cell-gas turbine (SOFC-GT) systems provide a thermodynamically high efficiency alternative for power generation from biofuels. In this study biofuels namely methane, ethanol, methanol, hydrogen, and ammonia are evaluated exergetically with respect to their performance at system level and in system components like heat exchangers, fuel cell, gas turbine, combustor, compressor, and the stack. Further, the fuel cell losses are investigated in detail with respect to their dependence on operating parameters such as fuel utilization, Nernst voltage, etc. as well as fuel specific parameters like heat effects. It is found that the heat effects play a major role in setting up the flows in the system and hence, power levels attained in individual components. The per pass fuel utilization dictates the efficiency of the fuel cell itself, but the system efficiency is not entirely dependent on fuel cell efficiency alone, but depends on the split between the fuel cell and gas turbine powers which in turn depends highly on the nature of the fuel and its chemistry. Counter intuitively it is found that with recycle, the fuel cell efficiency of methane is less than that of hydrogen but the system efficiency of methane is higher. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Bayesian modelling of household solid fuel use: insights towards designing effective interventions to promote fuel switching in Africa.

    Science.gov (United States)

    Rehfuess, Eva A; Briggs, David J; Joffe, Mike; Best, Nicky

    2010-10-01

    Indoor air pollution from solid fuel use is a significant risk factor for acute lower respiratory infections among children in sub-Saharan Africa. Interventions that promote a switch to modern fuels hold a large health promise, but their effective design and implementation require an understanding of the web of upstream and proximal determinants of household fuel use. Using Demographic and Health Survey data for Benin, Kenya and Ethiopia together with Bayesian hierarchical and spatial modelling, this paper quantifies the impact of household-level factors on cooking fuel choice, assesses variation between communities and districts and discusses the likely nature of contextual effects. Household- and area-level characteristics appear to interact as determinants of cooking fuel choice. In all three countries, wealth and the educational attainment of women and men emerge as important; the nature of area-level factors varies between countries. In Benin, a two-level model with spatial community random effects best explains the data, pointing to an environmental explanation. In Ethiopia and Kenya, a three-level model with unstructured community and district random effects is selected, implying relatively autonomous economic and social areas. Area-level heterogeneity, indicated by large median odds ratios, appears to be responsible for a greater share of variation in the data than household-level factors. This may be an indication that fuel choice is to a considerable extent supply-driven rather than demand-driven. Consequently, interventions to promote fuel switching will carefully need to assess supply-side limitations and devise appropriate policy and programmatic approaches to overcome them. To our knowledge, this paper represents the first attempt to model the determinants of solid fuel use, highlighting socio-economic differences between households and, notably, the dramatic influence of contextual effects. It illustrates the potential that multilevel and spatial

  4. Chlorine in solid fuels fired in pulverized fuel boilers sources, forms, reactions, and consequences: a literature review

    Energy Technology Data Exchange (ETDEWEB)

    David A. Tillman; Dao Duong; Bruce Miller [Foster Wheeler North America Corp. (United States)

    2009-07-15

    Chlorine is a significant source of corrosion and deposition, both from coal and from biomass, and in PF boilers. This investigation was designed to highlight the potential for corrosion risks associated with once-through units and advanced cycles. The research took the form of a detailed literature investigation to evaluate chlorine in solid fuels: coals of various ranks and origins, biomass fuels of a variety of types, petroleum cokes, and blends of the above. The investigation focused upon an extensive literature review of documents dating back to 1991. The focus is strictly corrosion and deposition. To address the deposition and corrosion issues, this review evaluates the following considerations: concentrations of chlorine in available solid fuels including various coals and biomass fuels, forms of chlorine in those fuels, and reactions - including reactivities - of chlorine in such fuels. The assessment includes consideration of alkali metals and alkali earth elements as they react with, and to, the chlorine and other elements (e.g., sulfur) in the fuel and in the gaseous products of combustion. The assessment also includes other factors of combustion: for example, combustion conditions including excess O{sub 2} and combustion temperatures. It also considers analyses conducted at all levels: theoretical calculations, bench scale laboratory data and experiments, pilot plant experiments, and full scale plant experience. Case studies and plant surveys form a significant consideration in this review. The result of this investigation focuses upon the concentrations of chlorine acceptable in coals burned exclusively, in coals burned with biomass, and in biomass cofired with coal. Values are posited based upon type of fuel and combustion technology. Values are also posited based upon both first principles and field experience. 86 refs., 8 figs., 7 tabs.

  5. Modeling the burnout of solid polydisperse fuel under the conditions of external heat transfer

    Science.gov (United States)

    Skorik, I. A.; Goldobin, Yu. M.; Tolmachev, E. M.; Gal'perin, L. G.

    2013-11-01

    A self-similar burnout mode of solid polydisperse fuel is considered taking into consideration heat transfer between fuel particles, gases, and combustion chamber walls. A polydisperse composition of fuel is taken into account by introducing particle distribution functions by radiuses obtained for the kinetic and diffusion combustion modes. Equations for calculating the temperatures of particles and gases are presented, which are written for particles average with respect to their distribution functions by radiuses taking into account the fuel burnout ratio. The proposed equations take into consideration the influence of fuel composition, air excess factor, and gas recirculation ratio. Calculated graphs depicting the variation of particle and gas temperatures, and the fuel burnout ratio are presented for an anthracite-fired boiler.

  6. System modeling of an air-independent solid oxide fuel cell system for unmanned undersea vehicles

    Science.gov (United States)

    Burke, A. Alan; Carreiro, Louis G.

    To examine the feasibility of a solid oxide fuel cell (SOFC)-powered unmanned undersea vehicle (UUV), a system level analysis is presented that projects a possible integration of the SOFC stack, fuel steam reformer, fuel/oxidant storage and balance of plant components into a 21-in. diameter UUV platform. Heavy hydrocarbon fuel (dodecane) and liquid oxygen (LOX) are chosen as the preferred reactants. A maximum efficiency of 45% based on the lower heating value of dodecane was calculated for a system that provides 2.5 kW for 40 h. Heat sources and sinks have been coupled to show viable means of thermal management. The critical design issues involve proper recycling of exhaust steam from the fuel cell back into the reformer and effective use of the SOFC stack radiant heat for steam reformation of the hydrocarbon fuel.

  7. 3-Dimensional Computational Fluid Dynamics Modeling of Solid Oxide Fuel Cell Using Different Fuels

    Science.gov (United States)

    2011-01-01

    major types of fuel cells in practice are listed below: Polymer Electrolyte Membrane Fuel Cell ( PEMFC ) Alkaline Fuel cell (AFC) Phosphoric Acid...Material Operating Temperature (oC) Efficiency (%) PEMFC H2, Methanol, Formic Acid Hydrated Organic Polymer < 90 40-50 AFC Pure H2 Aqueous

  8. Agglomeration and Deposition Behaviour of Solid Recovered Fuel

    DEFF Research Database (Denmark)

    Pedersen, Morten Nedergaard; Jensen, Peter Arendt; Hjuler, Klaus

    2016-01-01

    formation, or accumulation of impurities. The combustion of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), wood, and SRF were studied in a rotary drum furnace. The combustion was recorded on a camera (60 frames per second), so that any agglomeration or deposition of fuel or ash...

  9. Child mortality from solid-fuel use in India: a nationally-representative case-control study

    Directory of Open Access Journals (Sweden)

    Bassani Diego G

    2010-08-01

    Full Text Available Abstract Background Most households in low and middle income countries, including in India, use solid fuels (coal/coke/lignite, firewood, dung, and crop residue for cooking and heating. Such fuels increase child mortality, chiefly from acute respiratory infection. There are, however, few direct estimates of the impact of solid fuel on child mortality in India. Methods We compared household solid fuel use in 1998 between 6790 child deaths, from all causes, in the previous year and 609 601 living children living in 1.1 million nationally-representative homes in India. Analyses were stratified by child's gender, age (neonatal, post-neonatal, 1-4 years and colder versus warmer states. We also examined the association of solid fuel to non-fatal pneumonias. Results Solid fuel use was very common (87% in households with child deaths and 77% in households with living children. After adjustment for demographic factors and living conditions, solid-fuel use significantly increase child deaths at ages 1-4 (prevalence ratio (PR boys: 1.30, 95%CI 1.08-1.56; girls: 1.33, 95%CI 1.12-1.58. More girls than boys died from exposure to solid fuels. Solid fuel use was also associated with non-fatal pneumonia (boys: PR 1.54 95%CI 1.01-2.35; girls: PR 1.94 95%CI 1.13-3.33. Conclusions Child mortality risks, from all causes, due to solid fuel exposure were lower than previously, but as exposure was common solid, fuel caused 6% of all deaths at ages 0-4, 20% of deaths at ages 1-4 or 128 000 child deaths in India in 2004. Solid fuel use has declined only modestly in the last decade. Aside from reducing exposure, complementary strategies such as immunization and treatment could also reduce child mortality from acute respiratory infections.

  10. Technology of solid-fuel-layer targets for laser-fusion experiments

    International Nuclear Information System (INIS)

    Musinski, D.L.; Henderson, T.M.; Pattinson, T.R.; Tarvin, J.A.

    1979-01-01

    An apparatus which produces uniform solid-fuel layers in glass-shell targets for laser irradiation is described. A low-power cw laser pulse is used to vaporize the fuel within a previously frozen target which is maintained in a cold-helium environment by a cryogenic shroud. The rapid refreezing that follows the pulse forms a uniform fuel layer on the inner surface of the glass shell. This apparatus and technique meet the restrictions imposed by the experimental target chamber. The method does not perturb the target position; nor does it preclude the usual diagnostic experimets since the shroud is retracted before the main laser pulse arrives. Successful laser irradiation and implosion of solid-fuel-layer targets at KMSF have confirmed the effectiveness and reliability of this system and extended the range of laser-target-interaction studies in the cryogenic regime

  11. Effects of accelerated degradation on metal supported thin film-based solid oxide fuel cell

    DEFF Research Database (Denmark)

    Reolon, R. P.; Sanna, S.; Xu, Yu

    2018-01-01

    A thin film-based solid oxide fuel cell is deposited on a Ni-based metal porous support by pulsed laser deposition with a multi-scale-graded microstructure design. The fuel cell, around 1 μm in thickness, is composed of a stabilized-zirconia/doped-ceria bi-layered dense electrolyte and nanostruct......A thin film-based solid oxide fuel cell is deposited on a Ni-based metal porous support by pulsed laser deposition with a multi-scale-graded microstructure design. The fuel cell, around 1 μm in thickness, is composed of a stabilized-zirconia/doped-ceria bi-layered dense electrolyte......, electrochemical performances are steady, indicating the stability of the cell. Under electrical load, a progressive degradation is activated. Post-test analysis reveals both mechanical and chemical degradation of the cell. Cracks and delamination of the thin films promote a significant nickel diffusion and new...

  12. High pressure operation of tubular solid oxide fuel cells and their intergration with gas turbines

    Energy Technology Data Exchange (ETDEWEB)

    Haynes, C.; Wepfer, W.J. [Georgia Institute of Technology, Atlanta, GA (United States)

    1996-12-31

    Fossil fuels continue to be used at a rate greater than that of their natural formation, and the current byproducts from their use are believed to have a detrimental effect on the environment (e.g. global warming). There is thus a significant impetus to have cleaner, more efficient fuel consumption alternatives. Recent progress has led to renewed vigor in the development of fuel cell technology, which has been shown to be capable of producing high efficiencies with relatively benign exhaust products. The tubular solid oxide fuel cell developed by Westinghouse Electric Corporation has shown significant promise. Modeling efforts have been and are underway to optimize and better understand this fuel cell technology. Thus far, the bulk of modeling efforts has been for operation at atmospheric pressure. There is now interest in developing high-efficiency integrated gas turbine/solid oxide fuel cell systems. Such operation of fuel cells would obviously occur at higher pressures. The fuel cells have been successfully modeled under high pressure operation and further investigated as integrated components of an open loop gas turbine cycle.

  13. Generator module architecture for a large solid oxide fuel cell power plant

    Science.gov (United States)

    Gillett, James E.; Zafred, Paolo R.; Riggle, Matthew W.; Litzinger, Kevin P.

    2013-06-11

    A solid oxide fuel cell module contains a plurality of integral bundle assemblies, the module containing a top portion with an inlet fuel plenum and a bottom portion receiving air inlet feed and containing a base support, the base supports dense, ceramic exhaust manifolds which are below and connect to air feed tubes located in a recuperator zone, the air feed tubes passing into the center of inverted, tubular, elongated, hollow electrically connected solid oxide fuel cells having an open end above a combustion zone into which the air feed tubes pass and a closed end near the inlet fuel plenum, where the fuel cells comprise a fuel cell stack bundle all surrounded within an outer module enclosure having top power leads to provide electrical output from the stack bundle, where the fuel cells operate in the fuel cell mode and where the base support and bottom ceramic air exhaust manifolds carry from 85% to all 100% of the weight of the stack, and each bundle assembly has its own control for vertical and horizontal thermal expansion control.

  14. An integrated appraisal of energy recovery options in the United Kingdom using solid recovered fuel derived from municipal solid waste.

    Science.gov (United States)

    Garg, A; Smith, R; Hill, D; Longhurst, P J; Pollard, S J T; Simms, N J

    2009-08-01

    This paper reports an integrated appraisal of options for utilising solid recovered fuels (SRF) (derived from municipal solid waste, MSW) in energy intensive industries within the United Kingdom (UK). Four potential co-combustion scenarios have been identified following discussions with industry stakeholders. These scenarios have been evaluated using (a) an existing energy and mass flow framework model, (b) a semi-quantitative risk analysis, (c) an environmental assessment and (d) a financial assessment. A summary of results from these evaluations for the four different scenarios is presented. For the given ranges of assumptions; SRF co-combustion with coal in cement kilns was found to be the optimal scenario followed by co-combustion of SRF in coal-fired power plants. The biogenic fraction in SRF (ca. 70%) reduces greenhouse gas (GHG) emissions significantly ( approximately 2500 g CO(2) eqvt./kg DS SRF in co-fired cement kilns and approximately 1500 g CO(2) eqvt./kg DS SRF in co-fired power plants). Potential reductions in electricity or heat production occurred through using a lower calorific value (CV) fuel. This could be compensated for by savings in fuel costs (from SRF having a gate fee) and grants aimed at reducing GHG emission to encourage the use of fuels with high biomass fractions. Total revenues generated from coal-fired power plants appear to be the highest ( 95 pounds/t SRF) from the four scenarios. However overall, cement kilns appear to be the best option due to the low technological risks, environmental emissions and fuel cost. Additionally, cement kiln operators have good experience of handling waste derived fuels. The scenarios involving co-combustion of SRF with MSW and biomass were less favourable due to higher environmental risks and technical issues.

  15. An integrated appraisal of energy recovery options in the United Kingdom using solid recovered fuel derived from municipal solid waste

    International Nuclear Information System (INIS)

    Garg, A.; Smith, R.; Hill, D.; Longhurst, P.J.; Pollard, S.J.T.; Simms, N.J.

    2009-01-01

    This paper reports an integrated appraisal of options for utilising solid recovered fuels (SRF) (derived from municipal solid waste, MSW) in energy intensive industries within the United Kingdom (UK). Four potential co-combustion scenarios have been identified following discussions with industry stakeholders. These scenarios have been evaluated using (a) an existing energy and mass flow framework model, (b) a semi-quantitative risk analysis, (c) an environmental assessment and (d) a financial assessment. A summary of results from these evaluations for the four different scenarios is presented. For the given ranges of assumptions; SRF co-combustion with coal in cement kilns was found to be the optimal scenario followed by co-combustion of SRF in coal-fired power plants. The biogenic fraction in SRF (ca. 70%) reduces greenhouse gas (GHG) emissions significantly (∼2500 g CO 2 eqvt./kg DS SRF in co-fired cement kilns and ∼1500 g CO 2 eqvt./kg DS SRF in co-fired power plants). Potential reductions in electricity or heat production occurred through using a lower calorific value (CV) fuel. This could be compensated for by savings in fuel costs (from SRF having a gate fee) and grants aimed at reducing GHG emission to encourage the use of fuels with high biomass fractions. Total revenues generated from coal-fired power plants appear to be the highest ( Pounds 95/t SRF) from the four scenarios. However overall, cement kilns appear to be the best option due to the low technological risks, environmental emissions and fuel cost. Additionally, cement kiln operators have good experience of handling waste derived fuels. The scenarios involving co-combustion of SRF with MSW and biomass were less favourable due to higher environmental risks and technical issues.

  16. Regenerable mixed copper-iron-inert support oxygen carriers for solid fuel chemical looping combustion process

    Energy Technology Data Exchange (ETDEWEB)

    Siriwardane, Ranjani V.; Tian, Hanjing

    2016-12-20

    The disclosure provides an oxygen carrier for a chemical looping cycle, such as the chemical looping combustion of solid carbonaceous fuels, such as coal, coke, coal and biomass char, and the like. The oxygen carrier is comprised of at least 24 weight % (wt %) CuO, at least 10 wt % Fe2O3, and an inert support, and is typically a calcine. The oxygen carrier exhibits a CuO crystalline structure and an absence of iron oxide crystalline structures under XRD crystallography, and provides an improved and sustained combustion reactivity in the temperature range of 600.degree. C.-1000.degree. C. particularly for solid fuels such as carbon and coal.

  17. Tuneable diode laser gas analyser for methane measurements on a large scale solid oxide fuel cell

    Science.gov (United States)

    Lengden, Michael; Cunningham, Robert; Johnstone, Walter

    2011-10-01

    A new in-line, real time gas analyser is described that uses tuneable diode laser spectroscopy (TDLS) for the measurement of methane in solid oxide fuel cells. The sensor has been tested on an operating solid oxide fuel cell (SOFC) in order to prove the fast response and accuracy of the technology as compared to a gas chromatograph. The advantages of using a TDLS system for process control in a large-scale, distributed power SOFC unit are described. In future work, the addition of new laser sources and wavelength modulation will allow the simultaneous measurement of methane, water vapour, carbon-dioxide and carbon-monoxide concentrations.

  18. An initial applications study of ceria-gadolinia solid oxide fuel cells: V. 1

    Energy Technology Data Exchange (ETDEWEB)

    Bauen, A.; Hart, D.; Mould, B.

    1998-11-01

    Fuel cells are categorised by their electrolytes, and the solid oxide fuel cell is so called because its electrolyte consists of a solid ceramic oxide. Commonly this has been a form of zirconia, though other materials are now being considered for their different electrical properties. One of these, ceria doped with gadolinia, shows promise for use in lower temperature regimes than zirconia, and may open up different areas of a future market for consideration. This report considers the opportunities for ceria-gadolinia solid oxide fuel cell systems by comparing them with the application requirements in markets where fuel cells may have potential. The advantages and disadvantages of the technology are analysed, together with the state of the art in research and development. The direction in which research effort needs to move to address some of the issues is assessed. The report then draws conclusions regarding the potential of ceria-gadolinia in solid oxide fuel cell systems and in the energy markets as a whole. It should be noted that while this report is an applications study, some technology assessment has been included. Much of this is found in Volume 2. (author)

  19. Solid fuels, indoor air quality and health: a major issue in developing countries

    International Nuclear Information System (INIS)

    Mandin, C.; Ezratty, V.

    2009-01-01

    This article intends to do a synthesis of knowledge about the relationship between the indoor air pollution and the use of solid fuels ( such wood or biomass) for heating and cooking, from publications since 200 by specifying the fuels, the pollutants and the concerned geographical areas as well as the sanitary effects and more generally the impact in term of public health. (N.C.)

  20. Unified approach to the study of solid fuel combustion characteristics at high airflow speeds

    Science.gov (United States)

    Vnuchkov, D. A.; Lukashevich, S. V.; Nalivaychenko, D. G.; Zvegintsev, V. I.

    2017-10-01

    The main objective of the research is the development of guidelines for a unified approach to testing the combustion of different solid fuels in gaseous oxidant high-speed flow, so that research outcomes could be presented in a standardized and cohesive form. All the experiments were performed on a special experimental installation designed for quantification of the burning characteristics of different fuels in a wide range of the airflow parameters at the same geometry of the combustion chamber.

  1. Solid recovered fuel production through the mechanical-biological treatment of wastes

    OpenAIRE

    Velis, C. A.

    2010-01-01

    This thesis is concerned with the production of solid recovered fuel (SRF) from municipal solid waste using mechanical biological treatment (MBT) plants. It describes the first in-depth analysis of a UK MBT plant and addresses the fundamental research question: are MBT plants and their unit operations optimised to produce high quality SRF in the UK? A critical review of the process science and engineering of MBT provides timely insights into the quality management and standa...

  2. Three-phase boundary length in solid-oxide fuel cells: A mathematical model

    Energy Technology Data Exchange (ETDEWEB)

    Janardhanan, Vinod M. [Institutefor Chemical Technology and Polymer Chemistry, University of Karlsruhe (TH), Kaiserstr. 12, D-76128 Karlsruhe (Germany); Heuveline, Vincent; Deutschmann, Olaf [Institute for Applied and Numerical Mathematics, University of Karlsruhe (TH), Kaiserstr. 12, D-76128 Karlsruhe (Germany)

    2008-03-15

    A mathematical model to calculate the volume specific three-phase boundary length in the porous composite electrodes of solid-oxide fuel cell is presented. The model is exclusively based on geometrical considerations accounting for porosity, particle diameter, particle size distribution, and solids phase distribution. Results are presented for uniform particle size distribution as well as for non-uniform particle size distribution. (author)

  3. A New Solid/Liquid Hypergolic System: 3-amino 1,2,4-triazine and Nitric Acid

    Science.gov (United States)

    2016-04-01

    materials. These mixtures are useful in a variety of aviation applications such as space travel , where they are used to ignite rocket motors, or used as...motor, rocket , HAN 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT UU 18. NUMBER OF PAGES 26 19a. NAME OF RESPONSIBLE PERSON...adducts as additives of liquid/gel hypergols and solid hybrid rocket motor fuels: property and performance predictions. Aberdeen Proving Ground (MD): Army

  4. Application of Fly Ash from Solid Fuel Combustion in Concrete

    DEFF Research Database (Denmark)

    Pedersen, Kim Hougaard

    2008-01-01

    with implementation of low-NOx combustion technologies. The present thesis concerns three areas of importance within this field: 1) testing of fly ash adsorption behavior; 2) the influence of fuel type and combustion conditions on the ash adsorption behaviour including full-scale experiments at the power plant...... has a low sensitivity toward small variations in AEA adsorption between different fly ashes and it requires further work before a finished procedure is accomplished. Finally, it was shown that changes in temperature affect both test methods. Pulverized fuel has been combusted in an entrained flow...... formation. It was found that the AEA adsorption of the fly ash was reduced up to five times compared to reference operation, when the plant was operated with minimum furnace air staging, three levels of burners instead of four and without recycled flue gas. The lower AEA requirements of the fly ash...

  5. Perovskite solid electrolytes: Structure, transport properties and fuel cell applications

    DEFF Research Database (Denmark)

    Bonanos, N.; Knight, K.S.; Ellis, B.

    1995-01-01

    Doped barium cerate perovskites, first investigated by Iwahara and co-workers, have ionic conductivities of the order of 20 mS/cm at 800 degrees C making them attractive as fuel cell electrolytes for this temperature region. They have been used to construct laboratory scale fuel cells, which...... vapour transfer in a cell in which the perovskite is exposed to wet hydrogen on both sides. The evolution of transport properties with temperature is discussed in relation to structure. Neutron diffraction studies of doped and undoped barium cerate are reported, revealing a series of phase transitions...... between ambient temperature and 1000 degrees C. The available literature on chemical stability of cerate perovskites to reduction and attack by carbon dioxide is reviewed in brief....

  6. Degradation of solid oxide fuel cells with wood

    International Nuclear Information System (INIS)

    N Frank; M Saule; J Karl

    2006-01-01

    The Technical University of Munich investigates the degradation effects observed on SOFCs when fired with product gases from biomass gasification processes. The TUM has concentrated its research on tubular SOFCs. For this purpose tubular electrolyte-supported SOFCs have been manufactured using commercially available electrolyte tubes, anode foil and cathode paste. The tubular SOFCs were first run with hydrogen and synthetic fuels. Once stable and reproducible results were achieved, tests with product gas from four different biomass gasifiers have started. These gasifiers have been coupled to a gas cleaning device which includes sulphur and particle removal and pre-reforming. Different operation conditions of the gasifiers and the gas cleaning device have been realized and the corresponding fuel cell degradations have been analysed. (authors)

  7. Planar Solid-Oxide Fuel Cell Research and Development

    Science.gov (United States)

    2013-03-28

    electrodes and the electrolyte. The effect of the reduction in concentrations can be seen from the well-known Nernst potential equation , given by...reactions is modeled as a jump in the electric potential, which is determined using Nernst potential ( equation (18)) and activation polarization ( equation ...derivatives of structural cost functions. 2. Solution Methodology 2.1 Governing Equations (Fuel Cell) The three-dimensional SOFC model [30,31] utilized in

  8. Nuclear rockets

    International Nuclear Information System (INIS)

    Sarram, M.

    1972-01-01

    Nuclear energy has found many applications in space projects. This article deals with these applications. The first application is the use of nuclear energy for the production of electricity in space and the second main application is the use of nuclear energy for propulsion purposes in space flight. The main objective is to develop a 75000 pound thrust flight engine call NERVA by heating liquid hydrogen, in a nuclear reactor, from 420F to 4000 0 F. The paper describes in detail the salient features of the NERVA rocket as well as its comparison with the conventional chemical rockets. It is shown that a nuclear rocket using liquid hydrogen as medium is at least 85% more efficient as compared with the chemical rockets such as those used for the APOLLO moon flight

  9. Nuclear rockets

    Energy Technology Data Exchange (ETDEWEB)

    Sarram, M [Teheran Univ. (Iran). Inst. of Nuclear Science and Technology

    1972-02-01

    Nuclear energy has found many applications in space projects. This article deals with these applications. The first application is the use of nuclear energy for the production of electricity in space and the second main application is the use of nuclear energy for propulsion purposes in space flight. The main objective is to develop a 75000 pound thrust flight engine called NERVA by heating liquid hydrogen in a nuclear reactor. The paper describes in detail the salient features of the NERVA rocket as well as its comparison with the conventional chemical rockets. It is shown that a nuclear rocket using liquid hydrogen as medium is at least 85% more efficient as compared with the chemical rockets such as those used for the APOLLO moon flight.

  10. Plant Characteristics of an Integrated Solid Oxide Fuel Cell Cycle and a Steam Cycle

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2010-01-01

    Plant characteristics of a system containing a solid oxide fuel cell (SOFC) cycle on the top of a Rankine cycle were investigated. Natural gas (NG) was used as the fuel for the plant. A desulfurization reactor removes the sulfur content in the fuel, while a pre-reformer broke down the heavier...... recovery steam generator (HRSG). The remaining energy of the off-gases was recycled back to the topping cycle for further utilization. Several parameter studies were carried out to investigate the sensitivity of the suggested plant. It was shown that the operation temperature of the desulfurization unit...

  11. Thermodynamic analysis of an integrated solid oxide fuel cell cycle with a rankine cycle

    International Nuclear Information System (INIS)

    Rokni, Masoud

    2010-01-01

    Hybrid systems consisting of solid oxide fuel cells (SOFC) on the top of a steam turbine (ST) are investigated. The plants are fired by natural gas (NG). A desulfurization reactor removes the sulfur content in the fuel while a pre-reformer breaks down the heavier hydro-carbons. The pre-treated fuel enters then into the anode side of the SOFC. The remaining fuels after the SOFC stacks enter a burner for further burning. The off-gases are then used to produce steam for a Rankine cycle in a heat recovery steam generator (HRSG). Different system setups are suggested. Cyclic efficiencies up to 67% are achieved which is considerably higher than the conventional combined cycles (CC). Both adiabatic steam reformer (ASR) and catalytic partial oxidation (CPO) fuel pre-reformer reactors are considered in this investigation.

  12. Producing synthetic solid fuel from Kansk-Achinsk coal

    Energy Technology Data Exchange (ETDEWEB)

    Zverev, D.P.; Krichko, A.A.; Smirnova, T.S.; Markina, T.I.

    1981-01-01

    Studies were conducted by the Soviet Institute of Fossil Fuels in order to develop a technology and equipment configuration for thermal processing of coals using gas heat carriers in swirl chambers. Characteristics of the starting Irsha-Borodinskii coal and those of the products of thermal processing at 290-600 C are given. Testing the method showed that the products of high-speed thermal processing (thermocoal, semicoke, drier products) can be used as raw materials in hydrogenation, combustion, gasification, thermal benefication, briquetting and a series of other processes in metallurgy. (10 refs.) (In Russian)

  13. Solid oxide fuel cell systems development. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-12-15

    The main objective in this project has been to develop a generic and dynamic tool for SOFC systems simulation and development. Developing integrated fuel cell systems is very expensive and therefore having the right tools to reduce the development cost and time to market for products becomes an important feature. The tools developed in this project cover a wide range of needs in Dantherm Power, R and D, and can be divided into 3 categories: 1. Component selection modeling; to define component specification requirements and selection of suppliers. 2. Application simulation model built from scratch, which can simulate the interface between customer demand and system output and show operation behavior for different control settings. 3. System operation strategy optimization with respect to operation cost and customer benefits. a. Allows to see how system size, in terms of electricity and heat output, and operation strategy influences a specific business case. b. Gives a clear overview of how a different property, in the system, affects the economics (e.g. lifetime, electrical and thermal efficiency, fuel cost sensitivity, country of deployment etc.). The main idea behind the structure of the tool being separated into 3 layers is to be able to service different requirements, from changing stakeholders. One of the major findings in this project has been related to thermal integration between the existing installation in a private household and the fuel cell system. For a normal family requiring 4500 kWh of electricity a year, along with the possibility of only running the system during the heating season (winter), the heat storage demand is only 210kWh of heat with an approximate value of Dkr 160,- in extra gas consumption. In this case, it would be much more cost effective to dump the heat, in the house, and save the expense of adding heat storage to the system. This operation strategy is only valid in Denmark for the time being, since the feed-In-Tariff allows for a

  14. Effectiveness of paper-structured catalyst for the operation of biodiesel-fueled solid oxide fuel cell

    Science.gov (United States)

    Quang-Tuyen, Tran; Kaida, Taku; Sakamoto, Mio; Sasaki, Kazunari; Shiratori, Yusuke

    2015-06-01

    Mg/Al-hydrotalcite (HDT)-dispersed paper-structured catalyst (PSC) was prepared by a simple paper-making process. The PSC exhibited excellent catalytic activity for the steam reforming of model biodiesel fuel (BDF), pure oleic acid methyl ester (oleic-FAME, C19H36O2) which is a mono-unsaturated component of practical BDFs. The PSC exhibited fuel conversion comparable to a pelletized catalyst material, here, conventional Ni-zirconia cermet anode for solid oxide fuel cell (SOFC) with less than one-hundredth Ni weight. Performance of electrolyte-supported cell connected with the PSC was evaluated in the feed of oleic-FAME, and stable operation was achieved. After 60 h test, coking was not observed in both SOFC anode and PSC.

  15. Operating Point Optimization of a Hydrogen Fueled Hybrid Solid Oxide Fuel Cell-Steam Turbine (SOFC-ST Plant

    Directory of Open Access Journals (Sweden)

    Juanjo Ugartemendia

    2013-09-01

    Full Text Available This paper presents a hydrogen powered hybrid solid oxide fuel cell-steam turbine (SOFC-ST system and studies its optimal operating conditions. This type of installation can be very appropriate to complement the intermittent generation of renewable energies, such as wind generation. A dynamic model of an alternative hybrid SOFC-ST configuration that is especially suited to work with hydrogen is developed. The proposed system recuperates the waste heat of the high temperature fuel cell, to feed a bottoming cycle (BC based on a steam turbine (ST. In order to optimize the behavior and performance of the system, a two-level control structure is proposed. Two controllers have been implemented for the stack temperature and fuel utilization factor. An upper supervisor generates optimal set-points in order to reach a maximal hydrogen efficiency. The simulation results obtained show that the proposed system allows one to reach high efficiencies at rated power levels.

  16. Optimal design and operation of solid oxide fuel cell systems for small-scale stationary applications

    Science.gov (United States)

    Braun, Robert Joseph

    The advent of maturing fuel cell technologies presents an opportunity to achieve significant improvements in energy conversion efficiencies at many scales; thereby, simultaneously extending our finite resources and reducing "harmful" energy-related emissions to levels well below that of near-future regulatory standards. However, before realization of the advantages of fuel cells can take place, systems-level design issues regarding their application must be addressed. Using modeling and simulation, the present work offers optimal system design and operation strategies for stationary solid oxide fuel cell systems applied to single-family detached dwellings. A one-dimensional, steady-state finite-difference model of a solid oxide fuel cell (SOFC) is generated and verified against other mathematical SOFC models in the literature. Fuel cell system balance-of-plant components and costs are also modeled and used to provide an estimate of system capital and life cycle costs. The models are used to evaluate optimal cell-stack power output, the impact of cell operating and design parameters, fuel type, thermal energy recovery, system process design, and operating strategy on overall system energetic and economic performance. Optimal cell design voltage, fuel utilization, and operating temperature parameters are found using minimization of the life cycle costs. System design evaluations reveal that hydrogen-fueled SOFC systems demonstrate lower system efficiencies than methane-fueled systems. The use of recycled cell exhaust gases in process design in the stack periphery are found to produce the highest system electric and cogeneration efficiencies while achieving the lowest capital costs. Annual simulations reveal that efficiencies of 45% electric (LHV basis), 85% cogenerative, and simple economic paybacks of 5--8 years are feasible for 1--2 kW SOFC systems in residential-scale applications. Design guidelines that offer additional suggestions related to fuel cell

  17. Modified cermet fuel electrodes for solid oxide electrochemical cells

    Science.gov (United States)

    Ruka, Roswell J.; Spengler, Charles J.

    1991-01-01

    An exterior porous electrode (10), bonded to a solid oxygen ion conducting electrolyte (13) which is in contact with an interior electrode (14), contains coarse metal particles (12) of nickel and/or cobalt, having diameters from 3 micrometers to 35 micrometers, where the coarse particles are coated with a separate, porous, multiphase layer (17) containing fine metal particles of nickel and/or cobalt (18), having diameters from 0.05 micrometers to 1.75 micrometers and conductive oxide (19) selected from cerium oxide, doped cerium oxide, strontium titanate, doped strontium titanate and mixtures thereof.

  18. Indoor concentrations of nitrogen dioxide and sulfur dioxide from burning solid fuels for cooking and heating in Yunnan Province, China

    NARCIS (Netherlands)

    Seow, Wei Jie; Downward, George S; Wei, Hu; Rothman, Nathaniel; Reiss, Boris; Xu, Jun; Bassig, Bryan A; Li, Jihua; He, Jun; Hosgood, H Dean; Wu, Guoping; Chapman, Robert S; Tian, Linwei; Wei, Fusheng; Caporaso, Neil E; Vermeulen, Roel; Lan, Qing

    2016-01-01

    The Chinese national pollution census has indicated that the domestic burning of solid fuels is an important contributor to nitrogen dioxide (NO2 ) and sulfur dioxide (SO2 ) emissions in China. To characterize indoor NO2 and SO2 air concentrations in relation to solid fuel use and stove ventilation

  19. Development of materials for use in solid oxid fuel cells anodes using renewable fuels in direct operation

    International Nuclear Information System (INIS)

    Lima, D.B.P.L. de; Florio, D.Z. de; Bezerra, M.E.O.

    2016-01-01

    Fuel cells produce electrical current from the electrochemical combustion of a gas or liquid (H2, CH4, C2H5OH, CH3OH, etc.) inserted into the anode cell. An important class of fuel cells is the SOFC (Solid Oxide Cell Fuel). It has a ceramic electrolyte that transports protons (H +) or O-2 ions and operating at high temperatures (500-1000 °C) and mixed conductive electrodes (ionic and electronic) ceramics or cermets. This work aims to develop anodes for fuel cells of solid oxide (SOFC) in order to direct operations with renewable fuels and strategic for the country (such as bioethanol and biogas). In this context, it becomes important to study in relation to the ceramic materials, especially those that must be used in high temperatures. Some types of double perovskites such as Sr2MgMoO6 (or simply SMMO) have been used as anodes in SOFC. In this study were synthesized by the polymeric precursor method, analyzed and characterized different ceramic samples of families SMMO, doped with Nb, this is: Sr2 (MgMo)1-xNbxO6 with 0 ≤ x ≤ 0.2. The materials produced were characterized by various techniques such as, thermal analysis, X-ray diffraction and scanning electron microscopy, and electrical properties determined by dc and ac measurements in a wide range of temperature, frequency and partial pressure of oxygen. The results of this work will contribute to a better understanding of advanced ceramic properties with mixed driving (electronic and ionic) and contribute to the advancement of SOFC technology operating directly with renewable fuels. (author)

  20. Nickel/Yttria-stabilised zirconia cermet anodes for solid oxide fuel cells

    NARCIS (Netherlands)

    Primdahl, Søren

    1999-01-01

    This thesis deals with the porous Ni/yttria-stabilized zirconia (YSZ) cermet anode on a YSZ electrolyte for solid oxide fuel cells (SOFC). Such anodes are predominantly operated in moist hydrogen at 700°C to 1000°C, and the most important technological parameters are the polarization resistance and