WorldWideScience

Sample records for hydrogen rocket engines

  1. Additive Manufacturing a Liquid Hydrogen Rocket Engine

    Science.gov (United States)

    Jones, Carl P.; Robertson, Elizabeth H.; Koelbl, Mary Beth; Singer, Chris

    2016-01-01

    Space Propulsion is a 5 day event being held from 2nd May to the 6th May 2016 at the Rome Marriott Park Hotel in Rome, Italy. This event showcases products like Propulsion sub-systems and components, Production and manufacturing issues, Liquid, Solid, Hybrid and Air-breathing Propulsion Systems for Launcher and Upper Stages, Overview of current programmes, AIV issues and tools, Flight testing and experience, Technology building blocks for Future Space Transportation Propulsion Systems : Launchers, Exploration platforms & Space Tourism, Green Propulsion for Space Transportation, New propellants, Rocket propulsion & global environment, Cost related aspects of Space Transportation propulsion, Modelling, Pressure-Thrust oscillations issues, Impact of new requirements and regulations on design etc. in the Automotive, Manufacturing, Fabrication, Repair & Maintenance industries.

  2. Influence of hydrogen temperature on the stability of a rocket engine combustor operated with hydrogen and oxygen

    Science.gov (United States)

    Gröning, Stefan; Hardi, Justin; Suslov, Dmitry; Oschwald, Michael

    2017-03-01

    Since the late 1960s, low hydrogen injection temperature is known to have a destabilising effect on rocket engines with the propellant combination hydrogen/oxygen. Self-excited combustion instabilities of the first tangential mode have been found recently in a research rocket combustor operated with the propellant combination hydrogen/oxygen with a hydrogen temperature of 95 K. A hydrogen temperature ramping experiment has been performed with this research combustor to analyse the impact of hydrogen temperature on the self-excited combustion instabilities. The temperature was varied between 40 and 135 K. Contrary to past results found in literature, the combustor was found to be stable at low hydrogen temperatures while increased oscillation amplitudes of the first tangential mode were found at higher temperatures of around 100 K and above, which is consistent with previous observations of instabilities in this combustor. Further analysis shows that hydrogen temperature has a strong impact on the combustion chamber resonance frequencies. By varying the hydrogen injection temperature, the frequency of the first tangential mode is shifted to coincide with the second longitudinal resonance frequency of the liquid oxygen injector. Excitation of combustion chamber pressure oscillations was observed during such events.

  3. Air-Breathing Rocket Engines

    Science.gov (United States)

    1998-01-01

    This photograph depicts an air-breathing rocket engine prototype in the test bay at the General Applied Science Lab facility in Ronkonkoma, New York. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced Space Transportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  4. Liquid Rocket Engine Testing

    Science.gov (United States)

    2016-10-21

    Briefing Charts 3. DATES COVERED (From - To) 17 October 2016 – 26 October 2016 4. TITLE AND SUBTITLE Liquid Rocket Engine Testing 5a. CONTRACT NUMBER...298 (Rev. 8-98) Prescribed by ANSI Std. 239.18 Liquid Rocket Engine Testing SFTE Symposium 21 October 2016 Jake Robertson, Capt USAF AFRL... Rocket Lab Distribution A: Approved for Public Release; Distribution Unlimited. PA Clearance 16493 2Distribution A: Approved for Public Release

  5. Nuclear Rocket Engine Reactor

    CERN Document Server

    Lanin, Anatoly

    2013-01-01

    The development of a nuclear rocket engine reactor (NRER ) is presented in this book. The working capacity of an active zone NRER under mechanical and thermal load, intensive neutron fluxes, high energy generation (up to 30 MBT/l) in a working medium (hydrogen) at temperatures up to 3100 K is displayed. Design principles and bearing capacity of reactors area discussed on the basis of simulation experiments and test data of a prototype reactor. Property data of dense constructional, porous thermal insulating and fuel materials like carbide and uranium carbide compounds in the temperatures interval 300 - 3000 K are presented. Technological aspects of strength and thermal strength resistance of materials are considered. The design procedure of possible emergency processes in the NRER is developed and risks for their origination are evaluated. Prospects of the NRER development for pilotless space devices and piloted interplanetary ships are viewed.

  6. Nuclear rocket engine reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lanin, Anatoly

    2013-07-01

    Covers a new technology of nuclear reactors and the related materials aspects. Integrates physics, materials science and engineering Serves as a basic book for nuclear engineers and nuclear physicists. The development of a nuclear rocket engine reactor (NRER) is presented in this book. The working capacity of an active zone NRER under mechanical and thermal load, intensive neutron fluxes, high energy generation (up to 30 MBT/l) in a working medium (hydrogen) at temperatures up to 3100 K is displayed. Design principles and bearing capacity of reactors area discussed on the basis of simulation experiments and test data of a prototype reactor. Property data of dense constructional, porous thermal insulating and fuel materials like carbide and uranium carbide compounds in the temperatures interval 300 - 3000 K are presented. Technological aspects of strength and thermal strength resistance of materials are considered. The design procedure of possible emergency processes in the NRER is developed and risks for their origination are evaluated. Prospects of the NRER development for pilotless space devices and piloted interplanetary ships are viewed.

  7. Introduction to rocket science and engineering

    CERN Document Server

    Taylor, Travis S

    2009-01-01

    What Are Rockets? The History of RocketsRockets of the Modern EraRocket Anatomy and NomenclatureWhy Are Rockets Needed? Missions and PayloadsTrajectoriesOrbitsOrbit Changes and ManeuversBallistic Missile TrajectoriesHow Do Rockets Work? ThrustSpecific ImpulseWeight Flow RateTsiolkovsky's Rocket EquationStagingRocket Dynamics, Guidance, and ControlHow Do Rocket Engines Work? The Basic Rocket EngineThermodynamic Expansion and the Rocket NozzleExit VelocityRocket Engine Area Ratio and LengthsRocket Engine Design ExampleAre All Rockets the Same? Solid Rocket EnginesLiquid Propellant Rocket Engines

  8. Cryogenic rocket engine development at Delft aerospace rocket engineering

    NARCIS (Netherlands)

    Wink, J; Hermsen, R.; Huijsman, R; Akkermans, C.; Denies, L.; Barreiro, F.; Schutte, A.; Cervone, A.; Zandbergen, B.T.C.

    2016-01-01

    This paper describes the current developments regarding cryogenic rocket engine technology at Delft Aerospace Rocket Engineering (DARE). DARE is a student society based at Delft University of Technology with the goal of being the first student group in the world to launch a rocket into space. After

  9. Additive Manufacturing for Affordable Rocket Engines

    Science.gov (United States)

    West, Brian; Robertson, Elizabeth; Osborne, Robin; Calvert, Marty

    2016-01-01

    Additive manufacturing (also known as 3D printing) technology has the potential to drastically reduce costs and lead times associated with the development of complex liquid rocket engine systems. NASA is using 3D printing to manufacture rocket engine components including augmented spark igniters, injectors, turbopumps, and valves. NASA is advancing the process to certify these components for flight. Success Story: MSFC has been developing rocket 3D-printing technology using the Selective Laser Melting (SLM) process. Over the last several years, NASA has built and tested several injectors and combustion chambers. Recently, MSFC has 3D printed an augmented spark igniter for potential use the RS-25 engines that will be used on the Space Launch System. The new design is expected to reduce the cost of the igniter by a factor of four. MSFC has also 3D printed and tested a liquid hydrogen turbopump for potential use on an Upper Stage Engine. Additive manufacturing of the turbopump resulted in a 45% part count reduction. To understanding how the 3D printed parts perform and to certify them for flight, MSFC built a breadboard liquid rocket engine using additive manufactured components including injectors, turbomachinery, and valves. The liquid rocket engine was tested seven times in 2016 using liquid oxygen and liquid hydrogen. In addition to exposing the hardware to harsh environments, engineers learned to design for the new manufacturing technique, taking advantage of its capabilities and gaining awareness of its limitations. Benefit: The 3D-printing technology promises reduced cost and schedule for rocket engines. Cost is a function of complexity, and the most complicated features provide the largest opportunities for cost reductions. This is especially true where brazes or welds can be eliminated. The drastic reduction in part count achievable with 3D printing creates a waterfall effect that reduces the number of processes and drawings, decreases the amount of touch

  10. Air-Breathing Rocket Engine Test

    Science.gov (United States)

    2000-01-01

    This photograph depicts an air-breathing rocket engine that completed an hour or 3,600 seconds of testing at the General Applied Sciences Laboratory in Ronkonkoma, New York. Referred to as ARGO by its design team, the engine is named after the mythological Greek ship that bore Jason and the Argonauts on their epic voyage of discovery. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced SpaceTransportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  11. 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.

  12. The technique for Simulation of Transient Combustion Processes in the Rocket Engine Operating with Gaseous Fuel “Hydrogen and Oxygen”

    Science.gov (United States)

    Zubanov, V. M.; Stepanov, D. V.; Shabliy, L. S.

    2017-01-01

    The article describes the method for simulation of transient combustion processes in the rocket engine. The engine operates on gaseous propellant: oxygen and hydrogen. Combustion simulation was performed using the ANSYS CFX software. Three reaction mechanisms for the stationary mode were considered and described in detail. Reactions mechanisms have been taken from several sources and verified. The method for converting ozone properties from the Shomate equation to the NASA-polynomial format was described in detail. The way for obtaining quick CFD-results with intermediate combustion components using an EDM model was found. Modeling difficulties with combustion model Finite Rate Chemistry, associated with a large scatter of reference data were identified and described. The way to generate the Flamelet library with CFX-RIF is described. Formulated adequate reaction mechanisms verified at a steady state have also been tested for transient simulation. The Flamelet combustion model was recognized as adequate for the transient mode. Integral parameters variation relates to the values obtained during stationary simulation. A cyclic irregularity of the temperature field, caused by precession of the vortex core, was detected in the chamber with the proposed simulation technique. Investigations of unsteady processes of rocket engines including the processes of ignition were proposed as the area for application of the described simulation technique.

  13. Rocket Engine Altitude Simulation Technologies

    Science.gov (United States)

    Woods, Jody L.; Lansaw, John

    2010-01-01

    John C. Stennis Space Center is embarking on a very ambitious era in its rocket engine propulsion test history. The first new large rocket engine test stand to be built at Stennis Space Center in over 40 years is under construction. The new A3 Test Stand is designed to test very large (294,000 Ibf thrust) cryogenic propellant rocket engines at a simulated altitude of 100,000 feet. A3 Test Stand will have an engine testing chamber where the engine will be fired after the air in the chamber has been evacuated to a pressure at the simulated altitude of less than 0.16 PSIA. This will result in a very unique environment with extremely low pressures inside a very large chamber and ambient pressures outside this chamber. The test chamber is evacuated of air using a 2-stage diffuser / ejector system powered by 5000 lb/sec of steam produced by 27 chemical steam generators. This large amount of power and flow during an engine test will result in a significant acoustic and vibrational environment in and around A3 Test Stand.

  14. Metallic Hydrogen: A Game Changing Rocket Propellant

    Science.gov (United States)

    Silvera, Isaac F.

    2016-01-01

    The objective of this research is to produce metallic hydrogen in the laboratory using an innovative approach, and to study its metastability properties. Current theoretical and experimental considerations expect that extremely high pressures of order 4-6 megabar are required to transform molecular hydrogen to the metallic phase. When metallic hydrogen is produced in the laboratory it will be extremely important to determine if it is metastable at modest temperatures, i.e. remains metallic when the pressure is released. Then it could be used as the most powerful chemical rocket fuel that exists and revolutionize rocketry, allowing single-stage rockets to enter orbit and chemically fueled rockets to explore our solar system.

  15. Device for installing rocket engines

    Science.gov (United States)

    George, T. R., Jr. (Inventor)

    1976-01-01

    A device for installing rocket engines is reported that is supported at a cant relative to vertical by an axially extensible, tiltable pedestal. A lifting platform supports the rocket engine at its thrust chamber exit, including a mount having a concentric base characterized by a concave bearing surface, a plurality of uniformly spaced legs extended radially from the base, and an annular receiver coaxially aligned with the base and affixed to the distal ends of said legs for receiving the thrust chamber exit. The lifting platform rests on a seat concentrically related to the pedestal and affixed to an extended end portion thereof having a convex bearing surface mated in sliding engagement with the concave bearing surface of the annular base for accommodating a rocking motion of the platform.

  16. Measuring Model Rocket Engine Thrust Curves

    Science.gov (United States)

    Penn, Kim; Slaton, William V.

    2010-01-01

    This paper describes a method and setup to quickly and easily measure a model rocket engine's thrust curve using a computer data logger and force probe. Horst describes using Vernier's LabPro and force probe to measure the rocket engine's thrust curve; however, the method of attaching the rocket to the force probe is not discussed. We show how a…

  17. Metal Matrix Composites for Liquid Rocket Engines

    National Research Council Canada - National Science Library

    Shelley, J

    2001-01-01

    ...) technologies being developed for application to Liquid Rocket Engines (LIRE). Developments in LRE technology for the US Air Force are being tracked and planned through the Integrated High Payoff Rocket Propulsion Technologies Program (IHPRPT...

  18. Regenerative cooling for liquid rocket engines

    Science.gov (United States)

    Qi, Feng

    1995-01-01

    Heat transfer in the thrust chamber is of great importance in the design of liquid propellant rocket engines. Regenerative cooling is an advanced method which can ensure not only the proper running but also higher performance of a rocket engine. The theoretical model is complicated, it relates to fluid dynamics, heat transfer, combustion, etc... In this paper, a regenerative cooling model is presented. Effects such as radiation, heat transfer to environment, variable thermal properties and coking are included in the model. This model can be applied to all kinds of liquid propellant rocket engines as well as similar constructions. The modularized computer code is completed in the work.

  19. 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.

  20. Advanced Vortex Hybrid Rocket Engine (AVHRE) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop a unique Advanced Vortex Hybrid Rocket Engine (AVHRE) to achieve a safe, highly-reliable, low-cost and uniquely versatile propulsion...

  1. Advanced Vortex Hybrid Rocket Engine (AVHRE) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Orbital Technologies Corporation (ORBITEC) proposes to develop a unique Advanced Vortex Hybrid Rocket Engine (AVHRE) to achieve a highly-reliable, low-cost and...

  2. Yes--This is Rocket Science: MMCs for Liquid Rocket Engines

    National Research Council Canada - National Science Library

    Shelley, J

    2001-01-01

    The Air Force's Integrated High-Payoff Rocket Propulsion Technologies (IHPRPT) Program has established aggressive goals for both improved performance and reduced cost of rocket engines and components...

  3. CFD Simulation of Liquid Rocket Engine Injectors

    Science.gov (United States)

    Farmer, Richard; Cheng, Gary; Chen, Yen-Sen; Garcia, Roberto (Technical Monitor)

    2001-01-01

    Detailed design issues associated with liquid rocket engine injectors and combustion chamber operation require CFD methodology which simulates highly three-dimensional, turbulent, vaporizing, and combusting flows. The primary utility of such simulations involves predicting multi-dimensional effects caused by specific injector configurations. SECA, Inc. and Engineering Sciences, Inc. have been developing appropriate computational methodology for NASA/MSFC for the past decade. CFD tools and computers have improved dramatically during this time period; however, the physical submodels used in these analyses must still remain relatively simple in order to produce useful results. Simulations of clustered coaxial and impinger injector elements for hydrogen and hydrocarbon fuels, which account for real fluid properties, is the immediate goal of this research. The spray combustion codes are based on the FDNS CFD code' and are structured to represent homogeneous and heterogeneous spray combustion. The homogeneous spray model treats the flow as a continuum of multi-phase, multicomponent fluids which move without thermal or velocity lags between the phases. Two heterogeneous models were developed: (1) a volume-of-fluid (VOF) model which represents the liquid core of coaxial or impinger jets and their atomization and vaporization, and (2) a Blob model which represents the injected streams as a cloud of droplets the size of the injector orifice which subsequently exhibit particle interaction, vaporization, and combustion. All of these spray models are computationally intensive, but this is unavoidable to accurately account for the complex physics and combustion which is to be predicted, Work is currently in progress to parallelize these codes to improve their computational efficiency. These spray combustion codes were used to simulate the three test cases which are the subject of the 2nd International Workshop on-Rocket Combustion Modeling. Such test cases are considered by

  4. Influence of heat transfer on high pressure flame structure and stabilization in liquid rocket engines

    OpenAIRE

    Mari, Raphaël

    2015-01-01

    This research work deals with the problem of the flame stabilization in the context of high pressure liquid rocket engines. Flame stabilization in a rocket engine is a critical feature. An instability can lead to important damages of the engine or the destruction of the launcher and the satellite. The engines (Vulcain 2 and Vinci) of the Ariane 5, and the future Ariane 6, use the hydrogen/oxygen propellants. One characteristic of this couple is its high specific impulse. The launcher performa...

  5. Metal Matrix Composites for Rocket Engine Applications

    Science.gov (United States)

    McDonald, Kathleen R.; Wooten, John R.

    2000-01-01

    This document is from a presentation about the applications of Metal Matrix Composites (MMC) in rocket engines. Both NASA and the Air Force have goals which would reduce the costs and the weight of launching spacecraft. Charts show the engine weight distribution for both reuseable and expendable engine components. The presentation reviews the operating requirements for several components of the rocket engines. The next slide reviews the potential benefits of MMCs in general and in use as materials for Advanced Pressure Casting. The next slide reviews the drawbacks of MMCs. The reusable turbopump housing is selected to review for potential MMC application. The presentation reviews solutions for reusable turbopump materials, pointing out some of the issues. It also reviews the development of some of the materials.

  6. Hydrocarbon Rocket Engine Plume Imaging with Laser Induced Incandescence Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA/ Marshall Space Flight Center (MSFC) needs sensors that can be operated on rocket engine plume environments to improve NASA/SSC rocket engine performance. In...

  7. Closed-cycle liquid propellant rocket engines

    Science.gov (United States)

    Kuznetsov, N. D.

    1993-06-01

    The paper presents experience gained by SSSPE TRUD in development of NK-33, NK-43, NK-39, and NK-31 liquid propellant rocket engines, which are reusable, closed-cycle type, working on liquid oxygen and kerosene. Results are presented showing the engine structure efficiency, configuration rationality, and optimal thrust values which provide the following specific parameters: specific vacuum impulses in the range 331-353 s (for NK-33 and NK-31 engines, respectively) and specific weight of about 8 kg/tf (NK-33 and NK-43 engines). The problems which occurred during engine development and the study of the main components of these engines are discussed. The important technical data, materials, methodology, and bench development data are presented for the gas generator, turbopump assembly, combustion chamber and full-scale engines.

  8. The open-cycle gas-core nuclear rocket engine - Some engineering considerations.

    Science.gov (United States)

    Taylor, M. F.; Whitmarsh, C. L., Jr.; Sirocky, P. J., Jr.; Iwanczyk, L. C.

    1971-01-01

    A preliminary design study of a conceptual 6000-MW open-cycle gas-core nuclear rocket engine system was made. The engine has a thrust of 44,200 lb and a specific impulse of 4400 sec. The nuclear fuel is uranium-235 and the propellant is hydrogen. Critical fuel mass was calculated for several reactor configurations. Major components of the reactor (reflector, pressure vessel) and the waste heat rejection system were considered conceptually and were sized.

  9. Analysis of a Radioisotope Thermal Rocket Engine

    Science.gov (United States)

    Machado-Rodriguez, Jonathan P.; Landis, Geoffrey A.

    2017-01-01

    The Triton Hopper is a concept for a vehicle to explore the surface of Neptunes moon Triton, which uses a radioisotope heated rocket engine and in-situ propellant acquisition. The initial Triton Hopper conceptual design stores pressurized Nitrogen in a spherical tank to be used as the propellant. The aim of the research was to investigate the benefits of storing propellant at ambient temperature and heating it through a thermal block during engine operation, as opposed to storing gas at a high temperature.

  10. Software for Collaborative Engineering of Launch Rockets

    Science.gov (United States)

    Stanley, Thomas Troy

    2003-01-01

    The Rocket Evaluation and Cost Integration for Propulsion and Engineering software enables collaborative computing with automated exchange of information in the design and analysis of launch rockets and other complex systems. RECIPE can interact with and incorporate a variety of programs, including legacy codes, that model aspects of a system from the perspectives of different technological disciplines (e.g., aerodynamics, structures, propulsion, trajectory, aeroheating, controls, and operations) and that are used by different engineers on different computers running different operating systems. RECIPE consists mainly of (1) ISCRM a file-transfer subprogram that makes it possible for legacy codes executed in their original operating systems on their original computers to exchange data and (2) CONES an easy-to-use filewrapper subprogram that enables the integration of legacy codes. RECIPE provides a tightly integrated conceptual framework that emphasizes connectivity among the programs used by the collaborators, linking these programs in a manner that provides some configuration control while facilitating collaborative engineering tradeoff studies, including design to cost studies. In comparison with prior collaborative-engineering schemes, one based on the use of RECIPE enables fewer engineers to do more in less time.

  11. NASA's Hydrogen Outpost: The Rocket Systems Area at Plum Brook Station

    Science.gov (United States)

    Arrighi, Robert S.

    2016-01-01

    "There was pretty much a general knowledge about hydrogen and its capabilities," recalled former researcher Robert Graham. "The question was, could you use it in a rocket engine? Do we have the technology to handle it? How will it cool? Will it produce so much heat release that we can't cool the engine? These were the questions that we had to address." The National Aeronautics and Space Administration's (NASA) Glenn Research Center, referred to historically as the Lewis Research Center, made a concerted effort to answer these and related questions in the 1950s and 1960s. The center played a critical role transforming hydrogen's theoretical potential into a flight-ready propellant. Since then NASA has utilized liquid hydrogen to send humans and robots to the Moon, propel dozens of spacecraft across the universe, orbit scores of satellite systems, and power 135 space shuttle flights. Rocket pioneers had recognized hydrogen's potential early on, but its extremely low boiling temperature and low density made it impracticable as a fuel. The Lewis laboratory first demonstrated that liquid hydrogen could be safely utilized in rocket and aircraft propulsion systems, then perfected techniques to store, pump, and cleanly burn the fuel, as well as use it to cool the engine. The Rocket Systems Area at Lewis's remote testing area, Plum Brook Station, played a little known, but important role in the center's hydrogen research efforts. This publication focuses on the activities at the Rocket Systems Area, but it also discusses hydrogen's role in NASA's space program and Lewis's overall hydrogen work. The Rocket Systems Area included nine physically modest test sites and three test stands dedicated to liquid-hydrogen-related research. In 1962 Cleveland Plain Dealer reporter Karl Abram claimed, "The rocket facility looks more like a petroleum refinery. Its test rigs sprout pipes, valves and tanks. During the night test runs, excess hydrogen is burned from special stacks in the best

  12. Reusable Rocket Engine Turbopump Health Management System

    Science.gov (United States)

    Surko, Pamela

    1994-01-01

    A health monitoring expert system software architecture has been developed to support condition-based health monitoring of rocket engines. Its first application is in the diagnosis decisions relating to the health of the high pressure oxidizer turbopump (HPOTP) of Space Shuttle Main Engine (SSME). The post test diagnostic system runs off-line, using as input the data recorded from hundreds of sensors, each running typically at rates of 25, 50, or .1 Hz. The system is invoked after a test has been completed, and produces an analysis and an organized graphical presentation of the data with important effects highlighted. The overall expert system architecture has been developed and documented so that expert modules analyzing other line replaceable units may easily be added. The architecture emphasizes modularity, reusability, and open system interfaces so that it may be used to analyze other engines as well.

  13. Metallic Hydrogen - Potentially a High Energy Rocket Propellant

    Science.gov (United States)

    Cole, John; Silvera, Ike

    2007-01-01

    Pure metallic hydrogen is predicted to have a specific impulse (Isp) of 1700 seconds, but the reaction temperature is too high for current engine materials. Diluting metallic hydrogen with liquid hydrogen can reduce the reaction temperature to levels compatible with current material limits and still provide an Isp greater than 900 s. Metallic hydrogen has not yet been produced on earth, but experimental techniques exist that may change this situation. This paper will provide a brief description of metallic hydrogen and the status of experiments that may soon produce detectable quantities of this material in the lab. Also provided are some characteristics for diluted metallic hydrogen engines and launch vehicles.

  14. Numerical investigations of hybrid rocket engines

    Science.gov (United States)

    Betelin, V. B.; Kushnirenko, A. G.; Smirnov, N. N.; Nikitin, V. F.; Tyurenkova, V. V.; Stamov, L. I.

    2018-03-01

    Paper presents the results of numerical studies of hybrid rocket engines operating cycle including unsteady-state transition stage. A mathematical model is developed accounting for the peculiarities of diffusion combustion of fuel in the flow of oxidant, which is composed of oxygen-nitrogen mixture. Three dimensional unsteady-state simulations of chemically reacting gas mixture above thermochemically destructing surface are performed. The results show that the diffusion combustion brings to strongly non-uniform fuel mass regression rate in the flow direction. Diffusive deceleration of chemical reaction brings to the decrease of fuel regression rate in the longitudinal direction.

  15. Hyperthermal Environments Simulator for Nuclear Rocket Engine Development

    Science.gov (United States)

    Litchford, Ron J.; Foote, John P.; Clifton, W. B.; Hickman, Robert R.; Wang, Ten-See; Dobson, Christopher C.

    2011-01-01

    An arc-heater driven hyperthermal convective environments simulator was recently developed and commissioned for long duration hot hydrogen exposure of nuclear thermal rocket materials. This newly established non-nuclear testing capability uses a high-power, multi-gas, wall-stabilized constricted arc-heater to produce hightemperature pressurized hydrogen flows representative of nuclear reactor core environments, excepting radiation effects, and is intended to serve as a low-cost facility for supporting non-nuclear developmental testing of hightemperature fissile fuels and structural materials. The resulting reactor environments simulator represents a valuable addition to the available inventory of non-nuclear test facilities and is uniquely capable of investigating and characterizing candidate fuel/structural materials, improving associated processing/fabrication techniques, and simulating reactor thermal hydraulics. This paper summarizes facility design and engineering development efforts and reports baseline operational characteristics as determined from a series of performance mapping and long duration capability demonstration tests. Potential follow-on developmental strategies are also suggested in view of the technical and policy challenges ahead. Keywords: Nuclear Rocket Engine, Reactor Environments, Non-Nuclear Testing, Fissile Fuel Development.

  16. Boiler and Pressure Balls Monopropellant Thermal Rocket Engine

    Science.gov (United States)

    Greene, William D. (Inventor)

    2009-01-01

    The proposed technology is a rocket engine cycle utilizing as the propulsive fluid a low molecular weight, cryogenic fluid, typically liquid hydrogen, pressure driven, heated, and expelled through a nozzle to generate high velocity and high specific impulse discharge gas. The proposed technology feeds the propellant through the engine cycle without the use of a separate pressurization fluid and without the use of turbomachinery. Advantages of the proposed technology are found in those elements of state-of-the-art systems that it avoids. It does not require a separate pressurization fluid or a thick-walled primary propellant tank as is typically required for a classical pressure-fed system. Further, it does not require the acceptance of intrinsic reliability risks associated with the use of turbomachinery

  17. Orbit transfer rocket engine technology program

    Science.gov (United States)

    Gustafson, N. B.; Harmon, T. J.

    1993-10-01

    An advanced near term (1990's) space-based Orbit Transfer Vehicle Engine (OTVE) system was designed, and the technologies applicable to its construction, maintenance, and operations were developed under Tasks A through F of the Orbit Transfer Rocket Engine Technology Program. Task A was a reporting task. In Task B, promising OTV turbomachinery technologies were explored: two stage partial admission turbines, high velocity ratio diffusing crossovers, soft wear ring seals, advanced bearing concepts, and a rotordynamic analysis. In Task C, a ribbed combustor design was developed. Possible rib and channel geometries were chosen analytically. Rib candidates were hot air tested and laser velocimeter boundary layer analyses were conducted. A channel geometry was also chosen on the basis of laser velocimeter data. To verify the predicted heat enhancement effects, a ribbed calorimeter spool was hot fire tested. Under Task D, the optimum expander cycle engine thrust, performance and envelope were established for a set of OTV missions. Optimal nozzle contours and quick disconnects for modularity were developed. Failure Modes and Effects Analyses, maintenance and reliability studies and component study results were incorporated into the engine system. Parametric trades on engine thrust, mixture ratio, and area ratio were also generated. A control system and the health monitoring and maintenance operations necessary for a space-based engine were outlined in Task E. In addition, combustor wall thickness measuring devices and a fiberoptic shaft monitor were developed. These monitoring devices were incorporated into preflight engine readiness checkout procedures. In Task F, the Integrated Component Evaluator (I.C.E.) was used to demonstrate performance and operational characteristics of an advanced expander cycle engine system and its component technologies. Sub-system checkouts and a system blowdown were performed. Short transitions were then made into main combustor ignition and

  18. Developments in REDES: The Rocket Engine Design Expert System

    Science.gov (United States)

    Davidian, Kenneth O.

    1990-01-01

    The Rocket Engine Design Expert System (REDES) was developed at NASA-Lewis to collect, automate, and perpetuate the existing expertise of performing a comprehensive rocket engine analysis and design. Currently, REDES uses the rigorous JANNAF methodology to analyze the performance of the thrust chamber and perform computational studies of liquid rocket engine problems. The following computer codes were included in REDES: a gas properties program named GASP; a nozzle design program named RAO; a regenerative cooling channel performance evaluation code named RTE; and the JANNAF standard liquid rocket engine performance prediction code TDK (including performance evaluation modules ODE, ODK, TDE, TDK, and BLM). Computational analyses are being conducted by REDES to provide solutions to liquid rocket engine thrust chamber problems. REDES was built in the Knowledge Engineering Environment (KEE) expert system shell and runs on a Sun 4/110 computer.

  19. Development of Kabila rocket: A radioisotope heated thermionic plasma rocket engine

    OpenAIRE

    Mboyi, Kalomba; Ren, Junxue; Liu, Yu

    2015-01-01

    A new type of plasma rocket engine, the Kabila rocket, using a radioisotope heated thermionic heating chamber instead of a conventional combustion chamber or catalyst bed is introduced and it achieves specific impulses similar to the ones of conventional solid and bipropellant rockets. Curium-244 is chosen as a radioisotope heat source and a thermal reductive layer is also used to obtain precise thermionic emissions. The self-sufficiency principle is applied by simultaneously heating up the e...

  20. Problems of the mathematical description of rocket engines as plants

    Science.gov (United States)

    Kiforenko, B. N.

    2012-09-01

    Mathematical models of liquid-propellant, nuclear, and electric rocket engines are presented that more fully describe thrust generation than the classical models do. The optimal control of engine thrust is analyzed within the framework of Mayer's general variational problem. It is shown that the control of a rocket engine satisfying the necessary optimality conditions belongs to the boundary arc of the feasible control set between the point of maximum thrust and the point of maximum exhaust velocity

  1. Telemetry Boards Interpret Rocket, Airplane Engine Data

    Science.gov (United States)

    2009-01-01

    For all the data gathered by the space shuttle while in orbit, NASA engineers are just as concerned about the information it generates on the ground. From the moment the shuttle s wheels touch the runway to the break of its electrical umbilical cord at 0.4 seconds before its next launch, sensors feed streams of data about the status of the vehicle and its various systems to Kennedy Space Center s shuttle crews. Even while the shuttle orbiter is refitted in Kennedy s orbiter processing facility, engineers constantly monitor everything from power levels to the testing of the mechanical arm in the orbiter s payload bay. On the launch pad and up until liftoff, the Launch Control Center, attached to the large Vehicle Assembly Building, screens all of the shuttle s vital data. (Once the shuttle clears its launch tower, this responsibility shifts to Mission Control at Johnson Space Center, with Kennedy in a backup role.) Ground systems for satellite launches also generate significant amounts of data. At Cape Canaveral Air Force Station, across the Banana River from Kennedy s location on Merritt Island, Florida, NASA rockets carrying precious satellite payloads into space flood the Launch Vehicle Data Center with sensor information on temperature, speed, trajectory, and vibration. The remote measurement and transmission of systems data called telemetry is essential to ensuring the safe and successful launch of the Agency s space missions. When a launch is unsuccessful, as it was for this year s Orbiting Carbon Observatory satellite, telemetry data also provides valuable clues as to what went wrong and how to remedy any problems for future attempts. All of this information is streamed from sensors in the form of binary code: strings of ones and zeros. One small company has partnered with NASA to provide technology that renders raw telemetry data intelligible not only for Agency engineers, but also for those in the private sector.

  2. MHD thrust vectoring of a rocket engine

    Science.gov (United States)

    Labaune, Julien; Packan, Denis; Tholin, Fabien; Chemartin, Laurent; Stillace, Thierry; Masson, Frederic

    2016-09-01

    In this work, the possibility to use MagnetoHydroDynamics (MHD) to vectorize the thrust of a solid propellant rocket engine exhaust is investigated. Using a magnetic field for vectoring offers a mass gain and a reusability advantage compared to standard gimbaled, elastomer-joint systems. Analytical and numerical models were used to evaluate the flow deviation with a 1 Tesla magnetic field inside the nozzle. The fluid flow in the resistive MHD approximation is calculated using the KRONOS code from ONERA, coupling the hypersonic CFD platform CEDRE and the electrical code SATURNE from EDF. A critical parameter of these simulations is the electrical conductivity, which was evaluated using a set of equilibrium calculations with 25 species. Two models were used: local thermodynamic equilibrium and frozen flow. In both cases, chlorine captures a large fraction of free electrons, limiting the electrical conductivity to a value inadequate for thrust vectoring applications. However, when using chlorine-free propergols with 1% in mass of alkali, an MHD thrust vectoring of several degrees was obtained.

  3. A minimum cost tolerance allocation method for rocket engines and robust rocket engine design

    Science.gov (United States)

    Gerth, Richard J.

    1993-11-01

    Rocket engine design follows three phases: systems design, parameter design, and tolerance design. Systems design and parameter design are most effectively conducted in a concurrent engineering (CE) environment that utilize methods such as Quality Function Deployment and Taguchi methods. However, tolerance allocation remains an art driven by experience, handbooks, and rules of thumb. It was desirable to develop and optimization approach to tolerancing. The case study engine was the STME gas generator cycle. The design of the major components had been completed and the functional relationship between the component tolerances and system performance had been computed using the Generic Power Balance model. The system performance nominals (thrust, MR, and Isp) and tolerances were already specified, as were an initial set of component tolerances. However, the question was whether there existed an optimal combination of tolerances that would result in the minimum cost without any degradation in system performance.

  4. A minimum cost tolerance allocation method for rocket engines and robust rocket engine design

    Science.gov (United States)

    Gerth, Richard J.

    1993-01-01

    Rocket engine design follows three phases: systems design, parameter design, and tolerance design. Systems design and parameter design are most effectively conducted in a concurrent engineering (CE) environment that utilize methods such as Quality Function Deployment and Taguchi methods. However, tolerance allocation remains an art driven by experience, handbooks, and rules of thumb. It was desirable to develop and optimization approach to tolerancing. The case study engine was the STME gas generator cycle. The design of the major components had been completed and the functional relationship between the component tolerances and system performance had been computed using the Generic Power Balance model. The system performance nominals (thrust, MR, and Isp) and tolerances were already specified, as were an initial set of component tolerances. However, the question was whether there existed an optimal combination of tolerances that would result in the minimum cost without any degradation in system performance.

  5. Distributed Rocket Engine Testing Health Monitoring System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Leveraging the Phase I achievements of the Distributed Rocket Engine Testing Health Monitoring System (DiRETHMS) including its software toolsets and system building...

  6. Scale-Up of GRCop: From Laboratory to Rocket Engines

    Science.gov (United States)

    Ellis, David L.

    2016-01-01

    GRCop is a high temperature, high thermal conductivity copper-based series of alloys designed primarily for use in regeneratively cooled rocket engine liners. It began with laboratory-level production of a few grams of ribbon produced by chill block melt spinning and has grown to commercial-scale production of large-scale rocket engine liners. Along the way, a variety of methods of consolidating and working the alloy were examined, a database of properties was developed and a variety of commercial and government applications were considered. This talk will briefly address the basic material properties used for selection of compositions to scale up, the methods used to go from simple ribbon to rocket engines, the need to develop a suitable database, and the issues related to getting the alloy into a rocket engine or other application.

  7. Propellant Flow Actuated Piezoelectric Rocket Engine Igniter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Spark ignition of a bi-propellant rocket engine is a classic, proven, and generally reliable process. However, timing can be critical, and the control logic,...

  8. Distributed Rocket Engine Testing Health Monitoring System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The on-ground and Distributed Rocket Engine Testing Health Monitoring System (DiRETHMS) provides a system architecture and software tools for performing diagnostics...

  9. Oxidizer heat exchangers for rocket engine operation in idle modes

    Science.gov (United States)

    Kanic, P. G.; Kmiec, T. D.

    1987-01-01

    The heat exchanger concept is discussed together with its role in rocket engine operation in idle modes. Two heat exchanger designs (low and high heat transfer) utilizing different approaches to achieve stable oxygen vaporization are presented as well as their performance test results. It is concluded that compact and lightweight heat exchangers can be used in a stable manner under the 'idle' operating conditions expected with the RL10 rocket engine.

  10. Current status of rocket developments in universities -development of a small hybrid rocket with a swirling oxidizer flow type engine

    OpenAIRE

    Yuasa, Saburo; Kitagawa, Koki

    2005-01-01

    To develop an experimental small hybrid rocket with a swirling gaseous oxygen flow type engine, we made a flight model engine. Burning tests of the engine showed that a maximum thrust of 692 N and a specific impulse of 263 s (at sea level) were achieved. We designed a small hybrid rocket with this engine. The rocket measured 1.8 m in length and 15.4 kg in mass. To confirm the flight stability of the rocket, wind tunnel tests using a 112-scale model of the rocket and simulations of the flight ...

  11. Development of Kabila rocket: A radioisotope heated thermionic plasma rocket engine

    Directory of Open Access Journals (Sweden)

    Kalomba Mboyi

    2015-04-01

    Full Text Available A new type of plasma rocket engine, the Kabila rocket, using a radioisotope heated thermionic heating chamber instead of a conventional combustion chamber or catalyst bed is introduced and it achieves specific impulses similar to the ones of conventional solid and bipropellant rockets. Curium-244 is chosen as a radioisotope heat source and a thermal reductive layer is also used to obtain precise thermionic emissions. The self-sufficiency principle is applied by simultaneously heating up the emitting material with the radioisotope decay heat and by powering the different valves of the plasma rocket engine with the same radioisotope decay heat using a radioisotope thermoelectric generator. This rocket engine is then benchmarked against a 1 N hydrazine thruster configuration operated on one of the Pleiades-HR-1 constellation spacecraft. A maximal specific impulse and power saving of respectively 529 s and 32% are achieved with helium as propellant. Its advantages are its power saving capability, high specific impulses and simultaneous ease of storage and restart. It can however be extremely voluminous and potentially hazardous. The Kabila rocket is found to bring great benefits to the existing spacecraft and further research should optimize its geometric characteristics and investigate the physical principals of its operation.

  12. Ignition of Hydrogen-Oxygen Rocket Combustor with Chlorine Trifluoride and Triethylaluminum

    Science.gov (United States)

    Gregory, John W.; Straight, David M.

    1961-01-01

    Ignition of a nominal-125-pound-thrust cold (2000 R) gaseous-hydrogen - liquid-oxygen rocket combustor with chlorine trifluoride (hypergolic with hydrogen) and triethylaluminum (hypergolic with oxygen) resulted in consistently smooth starting transients for a wide range of combustor operating conditions. The combustor exhaust nozzle discharged into air at ambient conditions. Each starting transient consisted of the following sequence of events: injection of the lead main propellant, injection of the igniter chemical, ignition of these two chemicals, injection of the second main propellant, ignition of the two main propellants, increase in chamber pressure to its terminal value, and cutoff of igniter-chemical flow. Smooth ignition was obtained with an ignition delay of less than 100 milliseconds for the reaction of the lead propellant with the igniter chemical using approximately 0.5 cubic inch (0-038 lb) of chlorine trifluoride or 1.0 cubic inch (0-031 lb) of triethylaluminum. These quantities of igniter chemical were sufficient to ignite a 20-percent-fuel hydrogen-oxygen mixture with a delay time of less than 15 milliseconds. Test results indicated that a simple, light weight chemical ignition system for hydrogen-oxygen rocket engines may be possible.

  13. CFD Analysis of Square Flow Channel in Thermal Engine Rocket Adventurer for Space Nuclear Application

    Energy Technology Data Exchange (ETDEWEB)

    Nam, S. H.; Suh, K. Y. [Seoul National University, Seoul (Korea, Republic of); Kang, S. G. [PHILOSOPHIA, Inc., Seoul (Korea, Republic of)

    2008-10-15

    Solar system exploration relying on chemical rockets suffers from long trip time and high cost. In this regard nuclear propulsion is an attractive option for space exploration. The performance of Nuclear Thermal Rocket (NTR) is more than twice that of the best chemical rocket. Resorting to the pure hydrogen (H{sub 2}) propellant the NTRs can possibly achieve as high as 1,000 s of specific impulse (I{sub sp}) representing the ratio of the thrust over the fuel consumption rate, as compared to only 425 s of H{sub 2}/O{sub 2} rockets. If we reflect on the mission to Mars, NTRs would reduce the round trip time to less than 300 days, instead of over 600 days with chemical rockets. This work presents CFD analysis of one Fuel Element (FE) of Thermal Engine Rocket Adventurer (TERA). In particular, one Square Flow Channel (SFC) is analyzed in Square Lattice Honeycomb (SLHC) fuel to examine the effects of mass flow rate on rocket performance.

  14. Performance of a RBCC Engine in Rocket-Operation

    Science.gov (United States)

    Tomioka, Sadatake; Kubo, Takahiro; Noboru Sakuranaka; Tani, Koichiro

    Combination of a scramjet (supersonic combustion ramjet) flow-pass with embedded rocket engines (the combined system termed as Rocket-based Combined Cycle engine) are expected to be the most effective propulsion system for space launch vehicles. Either SSTO (Single Stage To Orbit) system or TSTO (Two Stage To Orbit) system with separation at high altitude needs final stage acceleration in space, so that the RBCC (Rocket Based Combined Cycle) engine should be operated as rocket engines. Performance of the scramjet combustor as the extension to the rocket nozzle, was experimentally evaluated by injecting inert gas at various pressure through the embedded rocket chamber while the whole sub-scaled model was placed in a low pressure chamber connected to an air-driven ejector system. The results showed that the thrust coefficient was about 1.2, the low value being found to mainly due to the friction force on the scramjet combustor wall, while blocking the scramjet flow pass’s opening to increase nozzle extension thrust surface, was found to have little effects on the thrust performance. The combustor was shortened to reduce the friction loss, however, degree of reduction was limited as friction decreased rapidly with distance from the onset of the scramjet combustor.

  15. An Object Model for a Rocket Engine Numerical Simulator

    Science.gov (United States)

    Mitra, D.; Bhalla, P. N.; Pratap, V.; Reddy, P.

    1998-01-01

    Rocket Engine Numerical Simulator (RENS) is a packet of software which numerically simulates the behavior of a rocket engine. Different parameters of the components of an engine is the input to these programs. Depending on these given parameters the programs output the behaviors of those components. These behavioral values are then used to guide the design of or to diagnose a model of a rocket engine "built" by a composition of these programs simulating different components of the engine system. In order to use this software package effectively one needs to have a flexible model of a rocket engine. These programs simulating different components then should be plugged into this modular representation. Our project is to develop an object based model of such an engine system. We are following an iterative and incremental approach in developing the model, as is the standard practice in the area of object oriented design and analysis of softwares. This process involves three stages: object modeling to represent the components and sub-components of a rocket engine, dynamic modeling to capture the temporal and behavioral aspects of the system, and functional modeling to represent the transformational aspects. This article reports on the first phase of our activity under a grant (RENS) from the NASA Lewis Research center. We have utilized Rambaugh's object modeling technique and the tool UML for this purpose. The classes of a rocket engine propulsion system are developed and some of them are presented in this report. The next step, developing a dynamic model for RENS, is also touched upon here. In this paper we will also discuss the advantages of using object-based modeling for developing this type of an integrated simulator over other tools like an expert systems shell or a procedural language, e.g., FORTRAN. Attempts have been made in the past to use such techniques.

  16. Development of Detonation Modeling Capabilities for Rocket Test Facilities: Hydrogen-Oxygen-Nitrogen Mixtures

    Science.gov (United States)

    Allgood, Daniel C.

    2016-01-01

    The objective of the presented work was to develop validated computational fluid dynamics (CFD) based methodologies for predicting propellant detonations and their associated blast environments. Applications of interest were scenarios relevant to rocket propulsion test and launch facilities. All model development was conducted within the framework of the Loci/CHEM CFD tool due to its reliability and robustness in predicting high-speed combusting flow-fields associated with rocket engines and plumes. During the course of the project, verification and validation studies were completed for hydrogen-fueled detonation phenomena such as shock-induced combustion, confined detonation waves, vapor cloud explosions, and deflagration-to-detonation transition (DDT) processes. The DDT validation cases included predicting flame acceleration mechanisms associated with turbulent flame-jets and flow-obstacles. Excellent comparison between test data and model predictions were observed. The proposed CFD methodology was then successfully applied to model a detonation event that occurred during liquid oxygen/gaseous hydrogen rocket diffuser testing at NASA Stennis Space Center.

  17. Blood Pump Development Using Rocket Engine Flow Simulation Technology

    Science.gov (United States)

    Kiris, Cetin C.; Kwak, Dochan

    2002-01-01

    This viewgraph presentation provides information on the transfer of rocket engine flow simulation technology to work involving the development of blood pumps. Details are offered regarding the design and requirements of mechanical heart assist devices, or VADs (ventricular assist device). There are various computational fluid dynamics issues involved in the visualization of flow in such devices, and these are highlighted and compared to those of rocket turbopumps.

  18. Nozzle flow of laser-heated radiating hydrogen with application to a laser-heated rocket

    Science.gov (United States)

    Kemp, N. H.; Root, R. G.

    1977-01-01

    This paper presents a model for the steady heating of flowing hydrogen by a CW 10.6 micron laser, to consider the feasibility of a laser-heated rocket. The hydrogen flow and the laser beam are parallel, and move into a converging-diverging nozzle. The absorption of laser energy is initiated by a laser-supported combustion wave. The hydrogen is in chemical equilibrium, absorbs laser energy by inverse Bremsstrahlung, and loses energy by radiation. The hydrogen flow was calculated from the rear of the LSC wave to the throat. Estimates of convective heat losses were made using a hydrogen boundary layer analysis. Specific impulse, obtained by expanding isentropically from the throat to 1 atm or a vacuum, varies from 1400 to 3000 s. Radiation losses are 5 to 20%, though the energy fluxes to the walls are quite high. Convective loss estimates are high enough to indicate that coupling to the hot gas flow is required for a 10 kW engine, but not for a 5 MW engine.

  19. Hydrogen in marine diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Voegler, Arne

    2010-07-01

    To investigate ways of reducing the yearly fuel oil consumption of the UK fishing fleet of 300 million liters, with associated carbon emissions of 802,500tonnes, experiments were undertaken to explore the feasibility of supplementing diesel fuel in compression ignition engines with both on board generated oxy hydrogen and bottled hydrogen. A Beta Marine BD722 3 cylinder engine fitted on board of a 9.4m vessel was used as a test bed and parameters monitored included the in cylinder pressure, fuel economy (tank to propeller thrust analysis), exhaust gas analysis and the thermal performance at various load conditions. The outlet of an oxy hydrogen electrolyzer was connected to the air intake of the engine and the performance was monitored by powering the unit directly from the engine's alternator and also by an external battery. Another approach used bottled hydrogen gas which was introduced into the air intake at varying rates between 5%- 20% of the overall energy supplied and measured values were compared with baseline data gathered during diesel fuel only operations. By examining the force applied to a mooring rope under static conditions the propeller thrust of the vessel underway was calculated for varying speeds and the mechanical engine efficiency for different fuel ratios and loads was determined. Results have confirmed that modest fuel savings can be achieved by supplying hydrogen into the air intake of a diesel engine. The occurrence of engine knock at higher hydrogen supply rates was observed and it is indicated that this could be counter acted upon by shifting the injection timing closer towards top dead centre. (Author)

  20. Chemical Kinetics Phenomena in Rocket Engines

    Science.gov (United States)

    1952-06-01

    boric acid fluctuation bands are by far the most prominent feature of the spectrum of the exhaust flame from this propellant combination. Weak bands due...spectrum shows only the boric acid fluctuation bands with the super- imposed BO bands of Singh. Some weak bands appear above 6000 A on some of the...accurately. b. Aniline and Furfuryl Alcohol with YFNA. - The spectrum of this rocket flame appears to be continuous in the visible region, though weak bands which

  1. Rocket and Missile Container Engineering Guide

    Science.gov (United States)

    1982-01-01

    Asphalt Benzoates Benzoic acid Benzoic acid, sodium-o-ethylmercuri mercapto Betanaphthol Bismuth benzoate Borates Boric acid Bromobenzene...Cresol Creosote with copper oleate Cuprammonium process . Dichlorodimethyl succinate Formaldehyde GR-S rubber Hexylresorcinol Hydrogen sulfide

  2. Mean Line Pump Flow Model in Rocket Engine System Simulation

    Science.gov (United States)

    Veres, Joseph P.; Lavelle, Thomas M.

    2000-01-01

    A mean line pump flow modeling method has been developed to provide a fast capability for modeling turbopumps of rocket engines. Based on this method, a mean line pump flow code PUMPA has been written that can predict the performance of pumps at off-design operating conditions, given the loss of the diffusion system at the design point. The pump code can model axial flow inducers, mixed-flow and centrifugal pumps. The code can model multistage pumps in series. The code features rapid input setup and computer run time, and is an effective analysis and conceptual design tool. The map generation capability of the code provides the map information needed for interfacing with a rocket engine system modeling code. The off-design and multistage modeling capabilities of the code permit parametric design space exploration of candidate pump configurations and provide pump performance data for engine system evaluation. The PUMPA code has been integrated with the Numerical Propulsion System Simulation (NPSS) code and an expander rocket engine system has been simulated. The mean line pump flow code runs as an integral part of the NPSS rocket engine system simulation and provides key pump performance information directly to the system model at all operating conditions.

  3. Analysis of supercritical methane in rocket engine cooling channels

    NARCIS (Netherlands)

    Denies, L.; Zandbergen, B.T.C.; Natale, P.; Ricci, D.; Invigorito, M.

    2016-01-01

    Methane is a promising propellant for liquid rocket engines. As a regenerative coolant, it would be close to its critical point, complicating cooling analysis. This study encompasses the development and validation of a new, open-source computational fluid dynamics (CFD) method for analysis of

  4. Selecting and using materials for a nuclear rocket engine reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lanin, Anatolii G; Fedik, Ivan I [' Luch' Research and Production Association, Podol' sk, Moscow region (Russian Federation)

    2011-03-31

    This paper provides a historical account of how the nuclear rocket engine reactor was created and discusses the problem of selecting materials for a gas environment at a temperature of up to 3100 K and energy release of 30 MW per liter. (from the history of physics)

  5. Two-step rocket engine bipropellant valve concept

    Science.gov (United States)

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

    1969-01-01

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

  6. Multivariable optimization of liquid rocket engines using particle swarm algorithms

    Science.gov (United States)

    Jones, Daniel Ray

    Liquid rocket engines are highly reliable, controllable, and efficient compared to other conventional forms of rocket propulsion. As such, they have seen wide use in the space industry and have become the standard propulsion system for launch vehicles, orbit insertion, and orbital maneuvering. Though these systems are well understood, historical optimization techniques are often inadequate due to the highly non-linear nature of the engine performance problem. In this thesis, a Particle Swarm Optimization (PSO) variant was applied to maximize the specific impulse of a finite-area combustion chamber (FAC) equilibrium flow rocket performance model by controlling the engine's oxidizer-to-fuel ratio and de Laval nozzle expansion and contraction ratios. In addition to the PSO-controlled parameters, engine performance was calculated based on propellant chemistry, combustion chamber pressure, and ambient pressure, which are provided as inputs to the program. The performance code was validated by comparison with NASA's Chemical Equilibrium with Applications (CEA) and the commercially available Rocket Propulsion Analysis (RPA) tool. Similarly, the PSO algorithm was validated by comparison with brute-force optimization, which calculates all possible solutions and subsequently determines which is the optimum. Particle Swarm Optimization was shown to be an effective optimizer capable of quick and reliable convergence for complex functions of multiple non-linear variables.

  7. Rocket Engines from the Glushko Design Bureau - 1946-2000

    Science.gov (United States)

    Siddiqi, A. A.

    Valentin P. Glushko (1908-89) oversaw the most influential rocket engine design organization in the Soviet Union. Originally known as OKB-456, the design bureau designed first stage engines for almost all operational Soviet ICBMs, the exceptions being the UR-100 (U.S. Department of Defense code name SS-11) and the UR-100N (SS- 19). According to official information, the design bureau has developed more than 120 engines since the end of World War II [1]. This article will attempt to summarize the development of engines at the Glushko Design Bureau and identify its the main thematic trends over the course of 55 years.

  8. Hydrogen engine development: Experimental program

    Energy Technology Data Exchange (ETDEWEB)

    Van Blarigan, P. [Sandia National Lab., Livermore, CA (United States)

    1996-10-01

    In the continuing development of a hydrogen fueled IC engine optimized for application to a generator set or hybrid vehicle, experiments were performed at Sandia National Laboratories on two engine configurations. The intent is to maximize thermal efficiency while complying with strict emissions standards. The initial investigation was conducted utilizing a spark ignited 0.491 liter single cylinder Onan engine and has progressed to a spark ignited 0.850 liter modified for single cylinder operation Perkins engine. Both combustion chamber geometries were {open_quotes}pancake{close_quotes} shaped and achieved a compression ratio of 14:1. The engines were operated under premixed conditions. The results demonstrate that both engines can comply with the California Air Resources Board`s proposed Equivalent Zero Emission Vehicle standards for NO{sub x} during operation at an equivalence ratio of 0.4. The Onan engine achieved an indicated thermal efficiency of 43% at 1800 RPM, as determined by integration of the pressure-volume relationships. Initial experiments with the larger displacement Perkins engine have realized a gain, relative to the Onan engine, in indicated thermal efficiency of 2% at 1800 RPM, and 15% at 1200 RPM.

  9. Advanced active health monitoring system of liquid rocket engines

    Science.gov (United States)

    Qing, Xinlin P.; Wu, Zhanjun; Beard, Shawn; Chang, Fu-Kuo

    2008-11-01

    An advanced SMART TAPE system has been developed for real-time in-situ monitoring and long term tracking of structural integrity of pressure vessels in liquid rocket engines. The practical implementation of the structural health monitoring (SHM) system including distributed sensor network, portable diagnostic hardware and dedicated data analysis software is addressed based on the harsh operating environment. Extensive tests were conducted on a simulated large booster LOX-H2 engine propellant duct to evaluate the survivability and functionality of the system under the operating conditions of typical liquid rocket engines such as cryogenic temperature, vibration loads. The test results demonstrated that the developed SHM system could survive the combined cryogenic temperature and vibration environments and effectively detect cracks as small as 2 mm.

  10. Developing Avionics Hardware and Software for Rocket Engine Testing

    Science.gov (United States)

    Aberg, Bryce Robert

    2014-01-01

    My summer was spent working as an intern at Kennedy Space Center in the Propulsion Avionics Branch of the NASA Engineering Directorate Avionics Division. The work that I was involved with was part of Rocket University's Project Neo, a small scale liquid rocket engine test bed. I began by learning about the layout of Neo in order to more fully understand what was required of me. I then developed software in LabView to gather and scale data from two flowmeters and integrated that code into the main control software. Next, I developed more LabView code to control an igniter circuit and integrated that into the main software, as well. Throughout the internship, I performed work that mechanics and technicians would do in order to maintain and assemble the engine.

  11. Expert System Architecture for Rocket Engine Numerical Simulators: A Vision

    Science.gov (United States)

    Mitra, D.; Babu, U.; Earla, A. K.; Hemminger, Joseph A.

    1998-01-01

    Simulation of any complex physical system like rocket engines involves modeling the behavior of their different components using mostly numerical equations. Typically a simulation package would contain a set of subroutines for these modeling purposes and some other ones for supporting jobs. A user would create an input file configuring a system (part or whole of a rocket engine to be simulated) in appropriate format understandable by the package and run it to create an executable module corresponding to the simulated system. This module would then be run on a given set of input parameters in another file. Simulation jobs are mostly done for performance measurements of a designed system, but could be utilized for failure analysis or a design job such as inverse problems. In order to use any such package the user needs to understand and learn a lot about the software architecture of the package, apart from being knowledgeable in the target domain. We are currently involved in a project in designing an intelligent executive module for the rocket engine simulation packages, which would free any user from this burden of acquiring knowledge on a particular software system. The extended abstract presented here will describe the vision, methodology and the problems encountered in the project. We are employing object-oriented technology in designing the executive module. The problem is connected to the areas like the reverse engineering of any simulation software, and the intelligent systems for simulation.

  12. Parallelization of Rocket Engine Simulator Software (PRESS)

    Science.gov (United States)

    Cezzar, Ruknet

    1998-01-01

    /18/99). At the least, the research would need to be done on Windows 95/Windows NT based platforms. Moreover, with the acquisition of Lahey Fortran package for PC platform, and the existing Borland C + + 5. 0, we can do work on C + + wrapper issues. We have carefully studied the blueprint for Space Transportation Propulsion Integrated Design Environment for the next 25 years [13] and found the inclusion of HBCUs in that effort encouraging. Especially in the long period for which a map is provided, there is no doubt that HBCUs will grow and become better equipped to do meaningful research. In the shorter period, as was suggested in our presentation at the HBCU conference, some key decisions regarding the aging Fortran based software for rocket propellants will need to be made. One important issue is whether or not object oriented languages such as C + + or Java should be used for distributed computing. Whether or not "distributed computing" is necessary for the existing software is yet another, larger, question to be tackled with.

  13. Schlieren image velocimetry measurements in a rocket engine exhaust plume

    Science.gov (United States)

    Morales, Rudy; Peguero, Julio; Hargather, Michael

    2017-11-01

    Schlieren image velocimetry (SIV) measures velocity fields by tracking the motion of naturally-occurring turbulent flow features in a compressible flow. Here the technique is applied to measuring the exhaust velocity profile of a liquid rocket engine. The SIV measurements presented include discussion of visibility of structures, image pre-processing for structure visibility, and ability to process resulting images using commercial particle image velocimetry (PIV) codes. The small-scale liquid bipropellant rocket engine operates on nitrous oxide and ethanol as propellants. Predictions of the exhaust velocity are obtained through NASA CEA calculations and simple compressible flow relationships, which are compared against the measured SIV profiles. Analysis of shear layer turbulence along the exhaust plume edge is also presented.

  14. Multiobjective Optimization of Rocket Engine Pumps Using Evolutionary Algorithm

    Science.gov (United States)

    Oyama, Akira; Liou, Meng-Sing

    2001-01-01

    A design optimization method for turbopumps of cryogenic rocket engines has been developed. Multiobjective Evolutionary Algorithm (MOEA) is used for multiobjective pump design optimizations. Performances of design candidates are evaluated by using the meanline pump flow modeling method based on the Euler turbine equation coupled with empirical correlations for rotor efficiency. To demonstrate the feasibility of the present approach, a single stage centrifugal pump design and multistage pump design optimizations are presented. In both cases, the present method obtains very reasonable Pareto-optimal solutions that include some designs outperforming the original design in total head while reducing input power by one percent. Detailed observation of the design results also reveals some important design criteria for turbopumps in cryogenic rocket engines. These results demonstrate the feasibility of the EA-based design optimization method in this field.

  15. Transient flow characteristics in a rocket engine nozzle

    OpenAIRE

    Takahashi, Masahiro; Ueda, Shuichi; Tomita, Takeo; Takahashi, Mamoru; Tamura, Hiroshi; Aoki, Kenji; 高橋 政浩; 植田 修一; 冨田 健夫; 高橋 守; 田村 洋; 青木 賢治

    2002-01-01

    Transient flow characteristics in convergent-divergent nozzles with cold gaseous nitrogen were studied using axisymmetric Navier-Stokes computation. A mechanism which possibly causes serious side-load during the start-up transient of the rocket engine nozzle is discussed. The numerical results are compared with the experimental results for validation. In case of the nozzle, with which remarkable side-load peaks were observed in the experiment and the transition from the Free Shock Separation ...

  16. Preliminary Combustion Analysis toward Stability Estimation of Rocket Engine Combustor

    OpenAIRE

    Mizobuchi, Yasuhiro; Shimizu, Taro; Naito, Taiki; 溝渕, 泰寛; 清水, 太郎; 内藤, 大貴

    2011-01-01

    A combustion flow in a model combustor equipped with a single injector located at a non-center position of the face plate is numerically simulated to investigate the combustion oscillation driving term, so called 'Rayleigh Index term' which plays a key role when we estimate the combustion stability of rocket engine combustors. The simulation reproduces the unsteady but stabilized flame behavior and reveals the flame stabilization mechanism. The critical combustion oscillation mode, T-mode, is...

  17. Ablative material testing for low-pressure, low-cost rocket engines

    Science.gov (United States)

    Richter, G. Paul; Smith, Timothy D.

    1995-01-01

    The results of an experimental evaluation of ablative materials suitable for the production of light weight, low cost rocket engine combustion chambers and nozzles are presented. Ten individual specimens of four different compositions of silica cloth-reinforced phenolic resin materials were evaluated for comparative erosion in a subscale rocket engine combustion chamber. Gaseous hydrogen and gaseous oxygen were used as propellants, operating at a nominal chamber pressure of 1138 kPa (165 psi) and a nominal mixture ratio (O/F) of 3.3. These conditions were used to thermally simulate operation with RP-1 and liquid oxygen, and achieved a specimen throat gas temperature of approximately 2456 K (4420 R). Two high-density composition materials exhibited high erosion resistance, while two low-density compositions exhibited approximately 6-75 times lower average erosion resistance. The results compare favorably with previous testing by NASA and provide adequate data for selection of ablatives for low pressure, low cost rocket engines.

  18. Liquid-propellant rocket engine testing at Arnold Engineering Development Center

    Science.gov (United States)

    Dehoff, Bryan; Tucker, Edgar K.; McAmis, Rob W.

    A continuing need exists for facilities to test both storable and cryogenic liquid-propellant rocket engines and stages at simulated altitude as part of a resposible acquisition risk reduction program. Storable propellant Intercontinental Ballistic Missile (ICBM) Post Boost Vehicles (PBV) require simulated altitude testing as part of the Aging and Surveillance programs designed to ensure an effective and reliable missile system. Likewise, simulated altitude testing is necessary acquisition risk reduction for advanced cryogenic rocket engines and stages that are being upgraded or developed to satisfy a variety of defense and commercial payload requirements. A review of liquid rocket test facilities at Arnold Engineering Development Center (AEDC) is presented. The facility capabilities used in support of acquisition risk reduction are described, as are new facility capabilities recently completed or funded. Furthermore, a description of the technology applications available at AEDC in support of liquid rocket diagnostics, analysis, and evaluation techniques is presented.

  19. Contact diagnostics of combustion products of rocket engines, their units, and systems

    Science.gov (United States)

    Ivanov, N. N.; Ivanov, A. N.

    2013-12-01

    This article is devoted to a new block-module device used in the diagnostics of condensed combustion products of rocket engines during research and development with liquid-propellant rocket engines (Glushko NPO Energomash; engines RD-171, RD-180, and RD-191) and solid-propellant rocket motors. Soot samplings from the supersonic high-temperature jet of a high-power liquid-propellant rocket engine were taken by the given device for the first time in practice for closed-exhaust lines. A large quantity of significant results was also obtained during a combustion investigation of solid propellants within solid-propellant rocket motors.

  20. Oxidation of Copper Alloy Candidates for Rocket Engine Applications

    Science.gov (United States)

    Ogbuji, Linus U. Thomas; Humphrey, Donald L.

    2002-01-01

    The gateway to affordable and reliable space transportation in the near future remains long-lived rocket-based propulsion systems; and because of their high conductivities, copper alloys remain the best materials for lining rocket engines and dissipating their enormous thermal loads. However, Cu and its alloys are prone to oxidative degradation -- especially via the ratcheting phenomenon of blanching, which occurs in situations where the local ambient can oscillate between oxidation and reduction, as it does in a H2/02- fuelled rocket engine. Accordingly, resistance to blanching degradation is one of the key requirements for the next generation of reusable launch vehicle (RLV) liner materials. Candidate copper alloys have been studied with a view to comparing their oxidation behavior, and hence resistance to blanching, in ambients corresponding to conditions expected in rocket engine service. These candidate materials include GRCop-84 and GRCop-42 (Cu - Cr-8 - Nb-4 and Cu - Cr-4 - Nb-2 respectively); NARloy-Z (Cu-3%Ag-0.5%Y), and GlidCop (Cu-O.l5%Al2O3 ODS alloy); they represent different approaches to improving the mechanical properties of Cu without incurring a large drop in thermal conductivity. Pure Cu (OFHC-Cu) was included in the study to provide a baseline for comparison. The samples were exposed for 10 hours in the TGA to oxygen partial pressures ranging from 322 ppm to 1.0 atmosphere and at temperatures of up to 700 C, and examined by SEM-EDS and other techniques of metallography. This paper will summarize the results obtained.

  1. Dynamical Model of Rocket Propellant Loading with Liquid Hydrogen

    Data.gov (United States)

    National Aeronautics and Space Administration — A dynamical model describing the multi-stage process of rocket propellant loading has been developed. It accounts for both the nominal and faulty regimes of...

  2. Investigation of Cooling Water Injection into Supersonic Rocket Engine Exhaust

    Science.gov (United States)

    Jones, Hansen; Jeansonne, Christopher; Menon, Shyam

    2017-11-01

    Water spray cooling of the exhaust plume from a rocket undergoing static testing is critical in preventing thermal wear of the test stand structure, and suppressing the acoustic noise signature. A scaled test facility has been developed that utilizes non-intrusive diagnostic techniques including Focusing Color Schlieren (FCS) and Phase Doppler Particle Anemometry (PDPA) to examine the interaction of a pressure-fed water jet with a supersonic flow of compressed air. FCS is used to visually assess the interaction of the water jet with the strong density gradients in the supersonic air flow. PDPA is used in conjunction to gain statistical information regarding water droplet size and velocity as the jet is broken up. Measurement results, along with numerical simulations and jet penetration models are used to explain the observed phenomena. Following the cold flow testing campaign a scaled hybrid rocket engine will be constructed to continue tests in a combusting flow environment similar to that generated by the rocket engines tested at NASA facilities. LaSPACE.

  3. Dual Expander Cycle Rocket Engine with an Intermediate, Closed-cycle Heat Exchanger

    Science.gov (United States)

    Greene, William D. (Inventor)

    2008-01-01

    A dual expander cycle (DEC) rocket engine with an intermediate closed-cycle heat exchanger is provided. A conventional DEC rocket engine has a closed-cycle heat exchanger thermally coupled thereto. The heat exchanger utilizes heat extracted from the engine's fuel circuit to drive the engine's oxidizer turbomachinery.

  4. Scaling of Performance in Liquid Propellant Rocket Engine Combustion Devices

    Science.gov (United States)

    Hulka, James R.

    2008-01-01

    This paper discusses scaling of combustion and combustion performance in liquid propellant rocket engine combustion devices. In development of new combustors, comparisons are often made between predicted performance in a new combustor and measured performance in another combustor with different geometric and thermodynamic characteristics. Without careful interpretation of some key features, the comparison can be misinterpreted and erroneous information used in the design of the new device. This paper provides a review of this performance comparison, including a brief review of the initial liquid rocket scaling research conducted during the 1950s and 1960s, a review of the typical performance losses encountered and how they scale, a description of the typical scaling procedures used in development programs today, and finally a review of several historical development programs to see what insight they can bring to the questions at hand.

  5. Enrichment Zoning Options for the Small Nuclear Rocket Engine (SNRE)

    Energy Technology Data Exchange (ETDEWEB)

    Bruce G. Schnitzler; Stanley K. Borowski

    2010-07-01

    Advancement of U.S. scientific, security, and economic interests through a robust space exploration program requires high performance propulsion systems to support a variety of robotic and crewed missions beyond low Earth orbit. In NASA’s recent Mars Design Reference Architecture (DRA) 5.0 study (NASA-SP-2009-566, July 2009), nuclear thermal propulsion (NTP) was again selected over chemical propulsion as the preferred in-space transportation system option because of its high thrust and high specific impulse (-900 s) capability, increased tolerance to payload mass growth and architecture changes, and lower total initial mass in low Earth orbit. An extensive nuclear thermal rocket technology development effort was conducted from 1955-1973 under the Rover/NERVA Program. The Small Nuclear Rocket Engine (SNRE) was the last engine design studied by the Los Alamos National Laboratory during the program. At the time, this engine was a state-of-the-art design incorporating lessons learned from the very successful technology development program. Past activities at the NASA Glenn Research Center have included development of highly detailed MCNP Monte Carlo transport models of the SNRE and other small engine designs. Preliminary core configurations typically employ fuel elements with fixed fuel composition and fissile material enrichment. Uniform fuel loadings result in undesirable radial power and temperature profiles in the engines. Engine performance can be improved by some combination of propellant flow control at the fuel element level and by varying the fuel composition. Enrichment zoning at the fuel element level with lower enrichments in the higher power elements at the core center and on the core periphery is particularly effective. Power flattening by enrichment zoning typically results in more uniform propellant exit temperatures and improved engine performance. For the SNRE, element enrichment zoning provided very flat radial power profiles with 551 of the 564

  6. Investigation of the cooling film distribution in liquid rocket engine

    Directory of Open Access Journals (Sweden)

    Luís Antonio Silva

    2011-05-01

    Full Text Available This study presents the results of the investigation of a cooling method widely used in the combustion chambers, which is called cooling film, and it is applied to a liquid rocket engine that uses as propellants liquid oxygen and kerosene. Starting from an engine cooling, whose film is formed through the fuel spray guns positioned on the periphery of the injection system, the film was experimentally examined, it is formed by liquid that seeped through the inner wall of the combustion chamber. The parameter used for validation and refinement of the theoretical penetration of the film was cooling, as this parameter is of paramount importance to obtain an efficient thermal protection inside the combustion chamber. Cold tests confirmed a penetrating cold enough cooling of the film for the length of the combustion chamber of the studied engine.

  7. Pulsed laser Rayleigh scattering diagnostic for hydrogen/oxygen rocket exit plane flowfield velocimetry

    Science.gov (United States)

    Zupanc, Frank J.

    1993-01-01

    A Doppler-resolved, pulsed laser Rayleigh scattering diagnostic has been developed to obtain local flowfield velocity measurements at the exit plane of a low thrust hydrogen/oxygen rocket engine operating in a high-altitude test facility. Fiberoptic signal collection was employed to obtain the forescatter and backscatter Doppler shifts necessary to resolve the axial and radial velocity components. A radial profile was obtained by traversing the collection probes along the beam path at the nozzle exit. The results are compared with theoretical predictions from a full Navier-Stokes model (RK/RPLUS). Significant discrepancies between the measured and predicted axial velocity profiles are observed, in terms of both magnitude and character. Radial velocity measurements exhibit excellent agreement with predictions near the centerline but show some departure off-axis. The discrepancies between theory and experiment are potentially the result of enhanced mixing between the core and fuel-film region beyond that predicted, and/or flow stratification between the hydrogen and oxygen injected into the central core region.

  8. Hybrid rocket engine research program at Ryerson University

    Energy Technology Data Exchange (ETDEWEB)

    Karpynczyk, J.; Greatrix, D.R. [Ryerson Polytechnic Univ., Toronto, ON (Canada). Dept. of Aerospace Engineering

    2007-07-01

    Hybrid rocket engines (HREs) are a combination of solid and liquid propellant rocket engine designs. A solid fuel grain is located in the main combustion chamber and nozzle aft, while a stored liquid or gaseous oxidizer source supplies the required oxygen content through a throttle valve, for combustion downstream in the main chamber. HREs have drawn significant interest in certain flight applications, as they can be advantageous in terms of cost, ease and safety in storage, controllability in flight, and availability of propellant constituents. Key factors that will lead to further practical usage of HREs for flight applications are their predictability and reproducibility of operational performance. This paper presented information on studies being conducted at Ryerson University aimed at analyzing and testing the performance of HREs. It discussed and illustrated the conventional HRE and analyzed engine performance considerations such as the fuel regression rate, mass flux about the fuel surface, burning rate, and zero transformation parameter. Other factors relating to HRE performance that were presented included induced forward and aft oxidizer flow swirl effects as a means for augmenting the fuel regression rate, stoichiometric grain length issues, and feed system stability. Last, the paper presented a simplified schematic diagram of a proposed thrust/test stand for HRE test firings. 2 refs., 3 figs.

  9. Using Innovative Technologies for Manufacturing and Evaluating Rocket Engine Hardware

    Science.gov (United States)

    Betts, Erin M.; Hardin, Andy

    2011-01-01

    Many of the manufacturing and evaluation techniques that are currently used for rocket engine component production are traditional methods that have been proven through years of experience and historical precedence. As we enter into a new space age where new launch vehicles are being designed and propulsion systems are being improved upon, it is sometimes necessary to adopt new and innovative techniques for manufacturing and evaluating hardware. With a heavy emphasis on cost reduction and improvements in manufacturing time, manufacturing techniques such as Direct Metal Laser Sintering (DMLS) and white light scanning are being adopted and evaluated for their use on J-2X, with hopes of employing both technologies on a wide variety of future projects. DMLS has the potential to significantly reduce the processing time and cost of engine hardware, while achieving desirable material properties by using a layered powdered metal manufacturing process in order to produce complex part geometries. The white light technique is a non-invasive method that can be used to inspect for geometric feature alignment. Both the DMLS manufacturing method and the white light scanning technique have proven to be viable options for manufacturing and evaluating rocket engine hardware, and further development and use of these techniques is recommended.

  10. Net-Shape HIP Powder Metallurgy Components for Rocket Engines

    Science.gov (United States)

    Bampton, Cliff; Goodin, Wes; VanDaam, Tom; Creeger, Gordon; James, Steve

    2005-01-01

    True net shape consolidation of powder metal (PM) by hot isostatic pressing (HIP) provides opportunities for many cost, performance and life benefits over conventional fabrication processes for large rocket engine structures. Various forms of selectively net-shape PM have been around for thirty years or so. However, it is only recently that major applications have been pursued for rocket engine hardware fabricated in the United States. The method employs sacrificial metallic tooling (HIP capsule and shaped inserts), which is removed from the part after HIP consolidation of the powder, by selective acid dissolution. Full exploitation of net-shape PM requires innovative approaches in both component design and materials and processing details. The benefits include: uniform and homogeneous microstructure with no porosity, irrespective of component shape and size; elimination of welds and the associated quality and life limitations; removal of traditional producibility constraints on design freedom, such as forgeability and machinability, and scale-up to very large, monolithic parts, limited only by the size of existing HIP furnaces. Net-shape PM HIP also enables fabrication of complex configurations providing additional, unique functionalities. The progress made in these areas will be described. Then critical aspects of the technology that still require significant further development and maturation will be discussed from the perspective of an engine systems builder and end-user of the technology.

  11. Ceramic Matrix Composite Turbine Disk for Rocket Engines

    Science.gov (United States)

    Effinger, Mike; Genge, Gary; Kiser, Doug

    2000-01-01

    NASA has recently completed testing of a ceramic matrix composite (CMC), integrally bladed disk (blisk) for rocket engine turbopumps. The turbopump's main function is to bring propellants from the tank to the combustion chamber at optimal pressures, temperatures, and flow rates. Advantages realized by using CMC blisks are increases in safety by increasing temperature margins and decreasing costs by increasing turbopump performance. A multidisciplinary team, involving materials, design, structural analysis, nondestructive inspection government, academia, and industry experts, was formed to accomplish the 4.5 year effort. This article will review some of the background and accomplishments of the CMC Blisk Program relative to the benefits of this technology.

  12. Simulation of liquid propellant rocket engine combustion instabilities

    Science.gov (United States)

    Ventrice, M. B.; Fang, J. C.; Purdy, K. R.

    1979-01-01

    A simulation technique for studying the high frequency combustion instabilities of liquid propellant rocket engines has been developed and used to investigate various aspects of instability phenomena. Of importance was investigation of the significance of the method of coupling the combustion and the gas dynamics of the system. Two coupling processes were studied: linear response of the combustion process to pressure fluctuations, and the nature of the resulting instabilities; and nonlinear response of the combustion process to velocity fluctuations, and the nature of the resulting instabilities. For the combustion model studied, nonlinear (velocity) coupling was found to more closely characterize liquid propellant instabilities.

  13. Effects of rocket engines on laser during lunar landing

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Xiong, E-mail: wanxiong1@126.com [Key Laboratory of Space Active Opto-Electronics Technology, Shanghai Institute of Technical Physics, Chinese Academy of Science, Shanghai 200083 (China); Key Laboratory of Nondestructive Test (Ministry of Education), Nanchang Hangkong University, Nanchang 330063 (China); Shu, Rong; Huang, Genghua [Key Laboratory of Space Active Opto-Electronics Technology, Shanghai Institute of Technical Physics, Chinese Academy of Science, Shanghai 200083 (China)

    2013-11-15

    In the Chinese moon exploration project “ChangE-3”, the laser telemeter and lidar are important equipments on the lunar landing vehicle. A low-thrust vernier rocket engine works during the soft landing, whose plume may influence on the laser equipments. An experiment has first been accomplished to evaluate the influence of the plume on the propagation characteristics of infrared laser under the vacuum condition. Combination with our theoretical analysis has given an appropriate assessment of the plume's effects on the infrared laser hence providing a valuable basis for the design of lunar landing systems.

  14. Solar thermal rocket engine (STRE) thrust characteristics at the change of engine operation mode and of the flight vehicle attitude in the solar system

    Science.gov (United States)

    Kudrin, O. I.

    1993-10-01

    Relationships are presented which describe changes in the thrust and specific impulse of a solar thermal rocket engine due to a change in the flow rate of the working fluid (hydrogen). Expressions are also presented which describe the variation of the STRE thrust and specific impulse with the distance between the flight vehicle and the sun. Results of calculations are presented for an STRE with afterburning of the working fluid (hydrogen + oxygen) using hydrogen heating by solar energy to a temperature of 2360 K.

  15. Orbital transfer rocket engine technology: Advanced engine study

    Science.gov (United States)

    Hayden, Warren R.

    1992-06-01

    An advanced LOX/LH2 engine study for the use of NASA and vehicle prime contractors in developing concepts for manned missions to the Moon, Mars, and Phobos is documented. Parametric design data was obtained at five engine thrusts from 7.5K lbf to 50K lbf. Also, a separate task evaluated engine throttling over a 20:1 range and operation at a mixture ratio of 12 plus or minus 1 versus the 6 plus or minus 1 nominal. Cost data was also generated for DDT&E, first unit production, and factors in other life cycle costs. The major limitation of the study was lack of contact with vehicle prime contractors to resolve the issues in vehicle/engine interfaces. The baseline Aerojet dual propellant expander cycle was shown capable of meeting all performance requirements with an expected long operational life due to the high thermal margins. The basic engine design readily accommodated the 20:1 throttling requirement and operation up to a mixture ratio of 10 without change. By using platinum for baffled injector construction the increased thermal margin allowed operation up to mixture ratio 13. An initial engine modeling with an Aerojet transient simulation code (named MLETS) indicates stable engine operation with the baseline control system. A throttle ratio of 4 to 5 seconds from 10 percent to 100 percent thrust is also predicted. Performance predictions are 483.1 sec at 7.5K lbf, 487.3 sec at 20K lbf, and 485.2 sec at 50K lbf with a mixture ratio of 6 and an area ratio of 1200. Engine envelopes varied from 120 in. length/53 in. exit diameter at 7.5K lbf to 305 in. length/136 in. exit diameter at 50 K lbf. Packaging will be an important consideration. Continued work is recommended to include more vehicle prime contractor/engine contractor joint assessment of the interface issues.

  16. Metallic Hydrogen: The Most Powerful Rocket Fuel Yet To Exist

    OpenAIRE

    Silvera, Isaac F.; Cole, John W.

    2010-01-01

    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 metast...

  17. Hydrogen hybrid vehicle engine development: Experimental program

    Energy Technology Data Exchange (ETDEWEB)

    Van Blarigan, P. [Sandia National Lab., Livermore, CA (United States)

    1995-09-01

    A hydrogen fueled engine is being developed specifically for the auxiliary power unit (APU) in a series type hybrid vehicle. Hydrogen is different from other internal combustion (IC) engine fuels, and hybrid vehicle IC engine requirements are different from those of other IC vehicle engines. Together these differences will allow a new engine design based on first principles that will maximize thermal efficiency while minimizing principal emissions. The experimental program is proceeding in four steps: (1) Demonstration of the emissions and the indicated thermal efficiency capability of a standard CLR research engine modified for higher compression ratios and hydrogen fueled operation. (2) Design and test a new combustion chamber geometry for an existing single cylinder research engine, in an attempt to improve on the baseline indicated thermal efficiency of the CLR engine. (3) Design and build, in conjunction with an industrial collaborator, a new full scale research engine designed to maximize brake thermal efficiency. Include a full complement of combustion diagnostics. (4) Incorporate all of the knowledge thus obtained in the design and fabrication, by an industrial collaborator, of the hydrogen fueled engine for the hybrid vehicle power train illustrator. Results of the CLR baseline engine testing are presented, as well as preliminary data from the new combustion chamber engine. The CLR data confirm the low NOx produced by lean operation. The preliminary indicated thermal efficiency data from the new combustion chamber design engine show an improvement relative to the CLR engine. Comparison with previous high compression engine results shows reasonable agreement.

  18. Distributed Health Monitoring System for Reusable Liquid Rocket Engines

    Science.gov (United States)

    Lin, C. F.; Figueroa, F.; Politopoulos, T.; Oonk, S.

    2009-01-01

    The ability to correctly detect and identify any possible failure in the systems, subsystems, or sensors within a reusable liquid rocket engine is a major goal at NASA John C. Stennis Space Center (SSC). A health management (HM) system is required to provide an on-ground operation crew with an integrated awareness of the condition of every element of interest by determining anomalies, examining their causes, and making predictive statements. However, the complexity associated with relevant systems, and the large amount of data typically necessary for proper interpretation and analysis, presents difficulties in implementing complete failure detection, identification, and prognostics (FDI&P). As such, this paper presents a Distributed Health Monitoring System for Reusable Liquid Rocket Engines as a solution to these problems through the use of highly intelligent algorithms for real-time FDI&P, and efficient and embedded processing at multiple levels. The end result is the ability to successfully incorporate a comprehensive HM platform despite the complexity of the systems under consideration.

  19. Using Innovative Technologies for Manufacturing Rocket Engine Hardware

    Science.gov (United States)

    Betts, E. M.; Eddleman, D. E.; Reynolds, D. C.; Hardin, N. A.

    2011-01-01

    Many of the manufacturing techniques that are currently used for rocket engine component production are traditional methods that have been proven through years of experience and historical precedence. As the United States enters into the next space age where new launch vehicles are being designed and propulsion systems are being improved upon, it is sometimes necessary to adopt innovative techniques for manufacturing hardware. With a heavy emphasis on cost reduction and improvements in manufacturing time, rapid manufacturing techniques such as Direct Metal Laser Sintering (DMLS) are being adopted and evaluated for their use on NASA s Space Launch System (SLS) upper stage engine, J-2X, with hopes of employing this technology on a wide variety of future projects. DMLS has the potential to significantly reduce the processing time and cost of engine hardware, while achieving desirable material properties by using a layered powder metal manufacturing process in order to produce complex part geometries. Marshall Space Flight Center (MSFC) has recently hot-fire tested a J-2X gas generator (GG) discharge duct that was manufactured using DMLS. The duct was inspected and proof tested prior to the hot-fire test. Using a workhorse gas generator (WHGG) test fixture at MSFC's East Test Area, the duct was subjected to extreme J-2X hot gas environments during 7 tests for a total of 537 seconds of hot-fire time. The duct underwent extensive post-test evaluation and showed no signs of degradation. DMLS manufacturing has proven to be a viable option for manufacturing rocket engine hardware, and further development and use of this manufacturing method is recommended.

  20. High speed diagnostics for characterization of oxygen / hydrogen rocket injector flowfields

    Science.gov (United States)

    Locke, Justin M.

    Temporally-resolved diagnostics are needed to characterize the highly-turbulent flowfields of rocket engine combustors. Two different high speed diagnostic techniques have been applied successfully to study the combustion and mixing characteristics of single-element shear-coaxial injector flowfield in a rocket combustor. Tunable diode laser absorption spectroscopy (TDLAS) is applied to make in-situ measurements with combusting gas-gas propellants, and high speed imaging incorporating backlighting is applied to combusting and non-combusting liquid-gas and gas-gas propellants. Tunable diode laser absorption spectroscopy has been used to make path-integrated temperature and H2O mole fraction measurements in a gaseous oxygen / gaseous hydrogen uni-element rocket chamber with hot background flow. Four mixture conditions were studied at a nominal chamber pressure of 115 psia. Near infrared diode lasers were utilized to target rovibrational transitions of water vapor, which is created through the combustion processes. Both direct absorption spectroscopy and wavelength modulation spectroscopy with second harmonic normalized by first harmonic (1f-normalized WMS-2 f) techniques were applied, with the harmonic detection technique found to yield the best results. Centerline measurements were made at two axial locations, in the near-injector region and far-field region further downstream. Time-resolved measurements of temperature and H2O mole fraction in the rocket chamber are presented. The TDLAS measurements shows clear differences between the near-injector and downstream measurement locations. Mean path-integrated temperatures and H2O mole fractions in the near-injector region are lower than the downstream measurement location. Fluctuations in path-integrated temperature and H2O mole fraction in the downstream location are significantly greater than the near-injector region. This suggests increased turbulence and larger-scale mixing processes are occurring in the downstream

  1. Rocket-Plume Spectroscopy Simulation for Hydrocarbon-Fueled Rocket Engines

    Science.gov (United States)

    Tejwani, Gopal D.

    2010-01-01

    The UV-Vis spectroscopic system for plume diagnostics monitors rocket engine health by using several analytical tools developed at Stennis Space Center (SSC), including the rocket plume spectroscopy simulation code (RPSSC), to identify and quantify the alloys from the metallic elements observed in engine plumes. Because the hydrocarbon-fueled rocket engine is likely to contain C2, CO, CH, CN, and NO in addition to OH and H2O, the relevant electronic bands of these molecules in the spectral range of 300 to 850 nm in the RPSSC have been included. SSC incorporated several enhancements and modifications to the original line-by-line spectral simulation computer program implemented for plume spectral data analysis and quantification in 1994. These changes made the program applicable to the Space Shuttle Main Engine (SSME) and the Diagnostic Testbed Facility Thruster (DTFT) exhaust plume spectral data. Modifications included updating the molecular and spectral parameters for OH, adding spectral parameter input files optimized for the 10 elements of interest in the spectral range from 320 to 430 nm and linking the output to graphing and analysis packages. Additionally, the ability to handle the non-uniform wavelength interval at which the spectral computations are made was added. This allowed a precise superposition of wavelengths at which the spectral measurements have been made with the wavelengths at which the spectral computations are done by using the line-by-line (LBL) code. To account for hydrocarbon combustion products in the plume, which might interfere with detection and quantification of metallic elements in the spectral region of 300 to 850 nm, the spectroscopic code has been enhanced to include the carbon-based combustion species of C2, CO, and CH. In addition, CN and NO have spectral bands in 300 to 850 nm and, while these molecules are not direct products of hydrocarbon-oxygen combustion systems, they can show up if nitrogen or a nitrogen compound is present

  2. Computer Modeling of a Rotating Detonation Engine in a Rocket Configuration

    Science.gov (United States)

    2015-03-01

    in a rocket . In the plateaus, the RDE has extracted as much energy from the fuel as possible, so additional time in the combustion chamber will not...impulse for rocket engines 53 of 150 sec falls below that of existing rocket engines. The nozzle and exhaust were assumed to be ideal, as were the...COMPUTER MODELING OF A ROTATING DETONATION ENGINE IN A ROCKET CONFIGURATION THESIS Nihar N. Shah, 1st Lt, USAF AFIT-ENY-MS-15-M-230 DEPARTMENT OF THE

  3. Development Testing of 1-Newton ADN-Based Rocket Engines

    Science.gov (United States)

    Anflo, K.; Gronland, T.-A.; Bergman, G.; Nedar, R.; Thormählen, P.

    2004-10-01

    With the objective to reduce operational hazards and improve specific and density impulse as compared with hydrazine, the Research and Development (R&D) of a new monopropellant for space applications based on AmmoniumDiNitramide (ADN), was first proposed in 1997. This pioneering work has been described in previous papers1,2,3,4 . From the discussion above, it is clear that cost savings as well as risk reduction are the main drivers to develop a new generation of reduced hazard propellants. However, this alone is not enough to convince a spacecraft builder to choose a new technology. Cost, risk and schedule reduction are good incentives, but a spacecraft supplier will ask for evidence that this new propulsion system meets a number of requirements within the following areas: This paper describes the ongoing effort to develop a storable liquid monopropellant blend, based on AND, and its specific rocket engines. After building and testing more than 20 experimental rocket engines, the first Engineering Model (EM-1) has now accumulated more than 1 hour of firing-time. The results from test firings have validated the design. Specific impulse, combustion stability, blow-down capability and short pulse capability are amongst the requirements that have been demonstrated. The LMP-103x propellant candidate has been stored for more than 1 year and initial material compatibility screening and testing has started. 1. Performance &life 2. Impact on spacecraft design &operation 3. Flight heritage Hereafter, the essential requirements for some of these areas are outlined. These issues are discussed in detail in a previous paper1 . The use of "Commercial Of The Shelf" (COTS) propulsion system components as much as possible is essential to minimize the overall cost, risk and schedule. This leads to the conclusion that the Technology Readiness Level (TRL) 5 has been reached for the thruster and propellant. Furthermore, that the concept of ADN-based propulsion is feasible.

  4. Combustion instability analysis for liquid propellant rocket engines

    Science.gov (United States)

    Kim, Y. M.; Chen, C. P.; Ziebarth, J. P.

    1992-01-01

    The multi-dimensional numerical model has been developed to analyze the nonlinear combustion instabilities in liquid-fueled engines. The present pressure-based approach can handle the implicit pressure-velocity coupling in a non-iterative way. The additional scalar conservation equations for the chemical species, the energy, and the turbulent transport quantities can be handled by the same predictor-corrector sequences. This method is time-accurate and it can be applicable to the all-speed, transient, multi-phase, and reacting flows. Special emphasis is given to the acoustic/vaporization interaction which may act as the crucial rate-controlling mechanism in the liquid-fueled rocket engines. The subcritical vaporization is modeled to account for the effects of variable thermophysical properties, non-unitary Lewis number in the gas-film, the Stefan flow effect, and the effect of transient liquid heating. The test cases include the one-dimenisonal fast transient non-reacting and reacting flows, and the multi-dimensional combustion instabilities encountered in the liquid-fueled rocket thrust chamber. The present numerical model successfully demonstrated the capability to simulate the fast transient spray-combusting flows in terms of the limiting-cycle amplitude phenomena, correspondence between combustion and acoustics, and the steep-fronted wave and flame propagation. The investigated parameters include the spray initial conditions, air-fuel mixture ratios, and the engine geometry. Stable and unstable operating conditions are found for the liquid-fueled combustors. Under certain conditions, the limiting cycle behavior of the combusting flowfields is obtained. The numerical results indicate that the spray vaporization processes play an important role in releasing thermal energy and driving the combustion instability.

  5. Fuel Chemistry And Combustion Distribution Effects On Rocket Engine Combustion Stability

    Science.gov (United States)

    2015-11-19

    AFRL-AFOSR-VA-TR-2016-0014 Effects of Increased Energy and Particulate Damping on Rocket William. Anderson PURDUE UNIVERSITY Final Report 11/19/2015...Distribution Effects On Rocket Engine Combustion Stability 5a. CONTRACT NUMBER 5b. GRANT NUMBER FA9550-10-1-0431 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...addition can be used to alter the combustion instability characteristics of liquid rocket engines. Fuels with increased energy, either due to higher heats

  6. Effect of Swirl on an Unstable Single-Element Gas-Gas Rocket Engine

    Science.gov (United States)

    2014-06-01

    combustion systems including gas turbines, rocket engines, and industrial furnaces. Swirl can have dramatic effects on the flowfield; these include jet growth...of the jet .16 In rocket engines, swirl injectors have several advantages over jet -type injectors; they are less sensitive to manufacturing defects...of Jet and Swirl Injectors,” Liquid Rocket Thrust Chambers: Aspects of Modeling, Analysis, and Design, edited by V. Yang, M. Habiballah, J. Hulka

  7. Romanian MRE Rocket Engines Program - An Early Endeavor

    Science.gov (United States)

    Rugescu, R. E.

    2002-01-01

    (MRE) was initiated in the years '60 of the past century at the Chair of Aerospace Sciences "Elie Carafoli" from the "Politehnica" University in Bucharest (PUB). Consisting of theoretical and experimental investigations in the form of computational methods and technological solutions for small size MRE-s and the concept of the test stand for these engines, the program ended in the construction of the first Romanian liquid rocket motors. Hermann Oberth and Dorin Pavel, were known from 1923, no experimental practice was yet tempted, at the time level of 1960. It was the intention of the developers at PUB to cover this gap and initiate a feasible, low-cost, demonstrative program of designing and testing experimental models of MRE. The research program was oriented towards future development of small size space carrier vehicles for scientific applications only, as an independent program with no connection to other defense programs imagined by the authorities in Bucharest, at that time. Consequently the entire financial support was assured by "Politehnica" university. computerized methods in the thermochemistry of heterogeneous combustion, for both steady and unsteady flows with chemical reactions and two phase flows. The research was gradually extended to the production of a professional CAD program for steady-state heat transfer simulations and the loading capacity analyses of the double wall, cooled thrust chamber. The resulting computer codes were run on a 360-30 IMB machine, beginning in 1968. Some of the computational methods were first exposed at the 9th International Conference on Applied Mechanics, held in Bucharest between June 23-27, 1969. hot testing of a series of storable propellant, variable thrust, variable geometry, liquid rocket motors, with a maximal thrust of 200N. A remotely controlled, portable test bad, actuated either automatically or manually and consisting of a 6-modules construction was built for this motor series, with a simple 8 analog

  8. Development of Advanced Small Hydrogen Engines

    Energy Technology Data Exchange (ETDEWEB)

    Sapru, Krishna; Tan, Zhaosheng; Chao, Ben

    2010-09-30

    The main objective of the project is to develop advanced, low cost conversions of small (< 25 hp) gasoline internal combustion engines (ICEs) to run on hydrogen fuel while maintaining the same performance and durability. This final technical report summarizes the results of i) the details of the conversion of several small gasoline ICEs to run on hydrogen, ii) the durability test of a converted hydrogen engine and iii) the demonstration of a prototype bundled canister solid hydrogen storage system. Peak power of the hydrogen engine achieves 60% of the power output of the gasoline counterpart. The efforts to boost the engine power with various options including installing the over-sized turbocharger, retrofit of custom-made pistons with high compression ratio, an advanced ignition system, and various types of fuel injection systems are not realized. A converted Honda GC160 engine with ACS system to run with hydrogen fuel is successful. Total accumulative runtime is 785 hours. A prototype bundled canister solid hydrogen storage system having nominal capacity of 1.2 kg is designed, constructed and demonstrated. It is capable of supporting a wide range of output load of a hydrogen generator.

  9. Unsteady Analyses of Valve Systems in Rocket Engine Testing Environments

    Science.gov (United States)

    Shipman, Jeremy; Hosangadi, Ashvin; Ahuja, Vineet

    2004-01-01

    This paper discusses simulation technology used to support the testing of rocket propulsion systems by performing high fidelity analyses of feed system components. A generalized multi-element framework has been used to perform simulations of control valve systems. This framework provides the flexibility to resolve the structural and functional complexities typically associated with valve-based high pressure feed systems that are difficult to deal with using traditional Computational Fluid Dynamics (CFD) methods. In order to validate this framework for control valve systems, results are presented for simulations of a cryogenic control valve at various plug settings and compared to both experimental data and simulation results obtained at NASA Stennis Space Center. A detailed unsteady analysis has also been performed for a pressure regulator type control valve used to support rocket engine and component testing at Stennis Space Center. The transient simulation captures the onset of a modal instability that has been observed in the operation of the valve. A discussion of the flow physics responsible for the instability and a prediction of the dominant modes associated with the fluctuations is presented.

  10. Hydrogen engine performance analysis. First annual report

    Energy Technology Data Exchange (ETDEWEB)

    Adt, Jr., R. R.; Swain, M. R.; Pappas, J. M.

    1978-08-01

    Many problems associated with the design and development of hydrogen-air breathing internal combustion engines for automotive applications have been identified by various domestic and foreign researchers. This project addresses the problems identified in the literature, seeks to evaluate potential solutions to these problems, and will obtain and document a design data-base convering the performance, operational and emissions characteristics essential for making rational decisions regarding the selection and design of prototype hydrogen-fueled, airbreathing engines suitable for manufacture for general automotive use. Information is included on the operation, safety, emission, and cost characteristics of hydrogen engines, the selection of a test engine and testing facilities, and experimental results. Baseline data for throttled and unthrottled, carburetted, hydrogen engine configurations with and without exhaust gas recirculation and water injection are presented. In addition to basic data gathering concerning performance and emissions, the test program conducted was formulated to address in detail the two major problems that must be overcome if hydrogen-fueled engines are to become viable: flashback and comparatively high NO/sub x/ emissions at high loads. In addition, the results of other hydrogen engine investigators were adjusted, using accepted methods, in order to make comparisons with the results of the present study. The comparisons revealed no major conflicts. In fact, with a few exceptions, there was found to be very good agreement between the results of the various studies.

  11. Failure characteristics analysis and fault diagnosis for liquid rocket engines

    CERN Document Server

    Zhang, Wei

    2016-01-01

    This book concentrates on the subject of health monitoring technology of Liquid Rocket Engine (LRE), including its failure analysis, fault diagnosis and fault prediction. Since no similar issue has been published, the failure pattern and mechanism analysis of the LRE from the system stage are of particular interest to the readers. Furthermore, application cases used to validate the efficacy of the fault diagnosis and prediction methods of the LRE are different from the others. The readers can learn the system stage modeling, analyzing and testing methods of the LRE system as well as corresponding fault diagnosis and prediction methods. This book will benefit researchers and students who are pursuing aerospace technology, fault detection, diagnostics and corresponding applications.

  12. Analysis of Acoustic Cavitation Surge in a Rocket Engine Turbopump

    Directory of Open Access Journals (Sweden)

    Hideaki Nanri

    2010-01-01

    Full Text Available In a liquid rocket engine, cavitation in an inducer of a turbopump sometimes causes instability phenomena when the inducer is operated at low inlet pressure. Cavitation surge (auto-oscillation, one such instability phenomenon, has been discussed mainly based on an inertia model assuming incompressible flow. When this model is used, the frequency of the cavitation surge decreases continuously as the inlet pressure of the turbopump decreases. However, we obtained an interesting experimental result in which the frequency of cavitation surge varied discontinuously. Therefore, we employed one-dimensional analysis based on an acoustic model in which the fluid is assumed to be compressible. The analytical result qualitatively corresponded with the experimental result.

  13. Integrated System Health Management (ISHM) Implementation in Rocket Engine Testing

    Science.gov (United States)

    Figueroa, Fernando; Morris, Jon; Turowski, Mark; Franzl, Richard; Walker, Mark; Kapadia, Ravi; Venkatesh, Meera

    2010-01-01

    A pilot operational ISHM capability has been implemented for the E-2 Rocket Engine Test Stand (RETS) and a Chemical Steam Generator (CSG) test article at NASA Stennis Space Center. The implementation currently includes an ISHM computer and a large display in the control room. The paper will address the overall approach, tools, and requirements. It will also address the infrastructure and architecture. Specific anomaly detection algorithms will be discussed regarding leak detection and diagnostics, valve validation, and sensor validation. It will also describe development and use of a Health Assessment Database System (HADS) as a repository for measurements, health, configuration, and knowledge related to a system with ISHM capability. It will conclude with a discussion of user interfaces, and a description of the operation of the ISHM system prior, during, and after testing.

  14. 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.

  15. Thermohydraulic Design Analysis Modeling for Korea Advanced NUclear Thermal Engine Rocket for Space Application

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-05-15

    Space exploration is a realistic and profitable goal for long-term humanity survival, although the harsh space environment imposes lots of severe challenges to space pioneers. To date, almost all space programs have relied upon Chemical Rockets (CRs) rating superior thrust level to transit from the Earth's surface to its orbit. However, CRs inherently have insurmountable barrier to carry out deep space missions beyond Earth's orbit due to its low propellant efficiency, and ensuing enormous propellant requirement and launch costs. Meanwhile, nuclear rockets typically offer at least two times the propellant efficiency of a CR and thus notably reduce the propellant demand. Particularly, a Nuclear Thermal Rocket (NTR) is a leading candidate for near-term manned missions to Mars and beyond because it satisfies a relatively high thrust as well as a high efficiency. The superior efficiency of NTRs is due to both high energy density of nuclear fuel and the low molecular weight propellant of Hydrogen (H{sub 2}) over the chemical reaction by-products. A NTR uses thermal energy released from a nuclear fission reactor to heat the H{sub 2} propellant and then exhausted the highly heated propellant through a propelling nozzle to produce thrust. A propellant efficiency parameter of rocket engines is specific impulse (I{sub s}p) which represents the ratio of the thrust over the propellant consumption rate. If the average exhaust H{sub 2} temperature of a NTR is around 3,000 K, the I{sub s}p can be achieved as high as 1,000 s as compared with only 450 - 500 s of the best CRs. For this reason, NTRs are favored for various space applications such as orbital tugs, lunar transports, and manned missions to Mars and beyond. The best known NTR development effort was conducted from 1955 to1974 under the ROVER and NERVA programs in the USA. These programs had successfully designed and tested many different reactors and engines. After these projects, the researches on NERVA derived

  16. ROCKET

    OpenAIRE

    CRUZ BARCELÓ, JULIA

    2015-01-01

    [In] The main objective of this project was to perform a stop-motion animation short film with my colleague Marta Soriano Gil, student of Fine Arts Degree at the Polytechnic University of Valencia, like myself. This project collects a year’s work developing the film, from the origins of the idea and the early stages of production to the final editing and audiovisual document. Rocket, is a project that has encompassed many disciplines, from the initial draws, designs and conc...

  17. Taming Liquid Hydrogen: The Centaur Upper Stage Rocket, 1958-2002

    Science.gov (United States)

    Dawson, Virginia P.; Bowles, Mark D.

    2004-01-01

    During its maiden voyage in May 1962, a Centaur upper stage rocket, mated to an Atlas booster, exploded 54 seconds after launch, engulfing the rocket in a huge fireball. Investigation revealed that Centaur's light, stainless-steel tank had split open, spilling its liquid-hydrogen fuel down its sides, where the flame of the rocket exhaust immediately ignited it. Coming less than a year after President Kennedy had made landing human beings on the Moon a national priority, the loss of Centaur was regarded as a serious setback for the National Aeronautics and Space Administration (NASA). During the failure investigation, Homer Newell, Director of Space Sciences, ruefully declared: "Taming liquid hydrogen to the point where expensive operational space missions can be committed to it has turned out to be more difficult than anyone supposed at the outset." After this failure, Centaur critics, led by Wernher von Braun, mounted a campaign to cancel the program. In addition to the unknowns associated with liquid hydrogen, he objected to the unusual design of Centaur. Like the Atlas rocket, Centaur depended on pressure to keep its paper-thin, stainless-steel shell from collapsing. It was literally inflated with its propellants like a football or balloon and needed no internal structure to give it added strength and stability. The so-called "pressure-stabilized structure" of Centaur, coupled with the light weight of its high- energy cryogenic propellants, made Centaur lighter and more powerful than upper stages that used conventional fuel. But, the critics argued, it would never become the reliable rocket that the United States needed.

  18. Performance of an Axisymmetric Rocket Based Combined Cycle Engine During Rocket Only Operation Using Linear Regression Analysis

    Science.gov (United States)

    Smith, Timothy D.; Steffen, Christopher J., Jr.; Yungster, Shaye; Keller, Dennis J.

    1998-01-01

    The all rocket mode of operation is shown to be a critical factor in the overall performance of a rocket based combined cycle (RBCC) vehicle. An axisymmetric RBCC engine was used to determine specific impulse efficiency values based upon both full flow and gas generator configurations. Design of experiments methodology was used to construct a test matrix and multiple linear regression analysis was used to build parametric models. The main parameters investigated in this study were: rocket chamber pressure, rocket exit area ratio, injected secondary flow, mixer-ejector inlet area, mixer-ejector area ratio, and mixer-ejector length-to-inlet diameter ratio. A perfect gas computational fluid dynamics analysis, using both the Spalart-Allmaras and k-omega turbulence models, was performed with the NPARC code to obtain values of vacuum specific impulse. Results from the multiple linear regression analysis showed that for both the full flow and gas generator configurations increasing mixer-ejector area ratio and rocket area ratio increase performance, while increasing mixer-ejector inlet area ratio and mixer-ejector length-to-diameter ratio decrease performance. Increasing injected secondary flow increased performance for the gas generator analysis, but was not statistically significant for the full flow analysis. Chamber pressure was found to be not statistically significant.

  19. A study of backfire in hydrogen engines

    Energy Technology Data Exchange (ETDEWEB)

    Sierens, R.; Rosseel, E. [University of Gent (Belgium)

    1999-07-01

    A 4 cylinder diesel engine is modified for hydrogen use by the installation of a gas carburettor. If the fuel-air mixture formed in the intake manifold pre-ignites before the inlet valve is closed, the result is backfire. This backfire phenomenon occurs easily in external mixture formation type hydrogen fuelled engines. In a first study the development of the pressure in the combustion chamber of one cylinder and the pressure in the inlet manifold is stored prior to backfire (during 32 successive cycles), as well as during and after backfire. The pressure traces are carefully examined and analysed to determine the start of combustion, the combustion duration, the maximum combustion pressure and the occurrence of knock for each of the successive cycles. It is observed that prior to backfire sudden pre-ignition combined with knock appears, which results in a run-away pre-ignition. In a second study the influence of engine parameters (ignition timing, supercharging conditions) on the occurrence of backfire are examined, as a function of the air-fuel ratio. Finally the behaviour of hythane mixtures (mixtures of natural gas and hydrogen) with respect to backfire is analysed in a GM V8 engine. For hythane mixtures with a hydrogen content of 80% or less, safe operation of the engine is guaranteed (no backfire nor knock), whatever the air-fuel ratio of the engine. (author)

  20. Hydrogen transport and storage in engineered microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Rambach, G. [Lawrence Livermore National Lab., CA (United States); Hendricks, C. [W.J. Schafer Associates, Livermore, CA (United States)

    1996-10-01

    This project is a collaboration between Lawrence Livermore National Laboratory (LLNL) and W.J. Schafer Associates (WJSA). The authors plan to experimentally verify the performance characteristics of engineered glass microspheres that are relevant to the storage and transport of hydrogen for energy applications. They will identify the specific advantages of hydrogen transport by microspheres, analyze the infrastructure implications and requirements, and experimentally measure their performance characteristics in realistic, bulk storage situations.

  1. Temperature State of Noncooled Nozzle Adjutage of Liquid Rocket Engine

    Directory of Open Access Journals (Sweden)

    V. S. Zarubin

    2015-01-01

    Full Text Available The increasing specific impulse of the liquid rocket engine (LRE, which is designed to operate in space or in rarefied atmosphere, is directly related to the increasing speed of the combustion gases in the outlet section of the nozzle due to increasing nozzle expansion ratio. An intensity of the convective heat transfer of LRE combustion with the supersonic part of a nozzle shell in the first approximation is inversely proportional to the cross sectional area of gas dynamic path and reduces substantially as approaching to the outlet section of the nozzle.Therefore, in case of large nozzle expansion ratio the use of modern heat-resistant materials allows us to implement its outlet section as a thin-walled uncooled adjutage. This design solution results in reducing total weight of nozzle and decreasing overall preheat of LRE propellant used to cool the engine chamber. For a given diameter of the nozzle outlet section and pressure of combustion gases in this section, to make informed choices of permissible length for uncooled adjutage, it is necessary to have a reliable estimate of its thermal state on the steady-state LRE operation. A mathematical model of the nozzle shell heat transfer with the gas stream taking into account the heat energy transfer by convection and radiation, as well as by heat conduction along the generatrix of the shell enables this estimate.Quantitative analysis of given mathematical model showed that, because of the comparatively low pressure and temperature level of combustion gases, it is acceptable to ignore their own radiation and absorption capacity as compared with the convective heat intensity and the surface nozzle radiation. Thus, re-radiation of its internal surface portions is a factor of importance. Its taking into consideration is the main feature of the developed mathematical model.

  2. Hydrogen Fuel Cell Engines and Related Technologies

    Science.gov (United States)

    2001-12-01

    The Hydrogen Fuel Cell Engines and Related Technologies report documents the first training course ever developed and made available to the transportation community and general public on the use hydrogen fuel cells in transportation. The course is designed to train a new generation of technicians in gaining a more complete understanding of the concepts, procedures, and technologies involved with hydrogen fuel cell use in transportation purposes. The manual contains 11 modules (chapters). The first eight modules cover (1) hydrogen properties, use and safety; and (2) fuel cell technology and its systems, fuel cell engine design and safety, and design and maintenance of a heavy duty fuel cell bus engine. The different types of fuel cells and hybrid electric vehicles are presented, however, the system descriptions and maintenance procedures focus on proton-exchange-membrane (PEM) fuel cells with respect to heavy duty transit applications. Modules 9 and 10 are intended to provide a better understanding of the acts, codes, regulations and guidelines concerning the use of hydrogen, as well as the safety guidelines for both hydrogen maintenance and fueling facilities. Module 11 presents a glossary and conversions.

  3. Quasi-2D Unsteady Flow Solver Module for Rocket Engine and Propulsion System Simulations

    National Research Council Canada - National Science Library

    Campell, Bryan T; Davis, Roger L

    2006-01-01

    .... The solver is targeted to the commercial dynamic simulation software package Simulink(Registered) for integration into a larger suite of modules developed for simulating rocket engines and propulsion systems...

  4. A Numerical Study of Combined Convective and Radiative Heat Transfer in a Rocket Engine Combustion Chamber

    National Research Council Canada - National Science Library

    Savur, Mehmet

    2002-01-01

    A numerical study was conducted to predict the combined convective and radiative heat transfer rates on the walls of a small aspect ratio cylinder representative of the scaled model of a rocket engine combustion chamber...

  5. Code Validation of CFD Heat Transfer Models for Liquid Rocket Engine Combustion Devices

    National Research Council Canada - National Science Library

    Coy, E. B

    2007-01-01

    .... The design of the rig and its capabilities are described. A second objective of the test rig is to provide CFD validation data under conditions relevant to liquid rocket engine thrust chambers...

  6. Proposal for a Concept Assessment of a Fission Fragment Rocket Engine (FFRE) Propelled Spacecraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A new technology, the Fission Fragment Rocket Engine (FFRE), requires small amounts of readily available, energy dense, long lasting fuel, significant thrust at...

  7. Distinctive features of the intrachamber instability of combustion in liquid-propellant rocket engines

    Science.gov (United States)

    Gotsulenko, V. V.

    2008-09-01

    Self-oscillations and certain of their regularities determined by solution of a degenerate system of differential equations that is used in considering combustion instability in combustion chambers of liquid-propellant rocket engines are modeled mathematically.

  8. Modeling of cooling channel flow in liquid-propellant rocket engines

    OpenAIRE

    Pizzarelli, Marco

    2008-01-01

    Ever since the development of liquid rocket engine, there has been a need to predict the peak heat flux that affects the engine material and thus to control the wall thermal behavior of rocket engine. To prevent thermal failure, the engine is generally cooled by means of a coolant that flows in passages that line the hottest part of the engine (i.e., combustion chamber and nozzle wall). This is the fluid-cooling system. If the coolant is one of the propellants, once it passes through th...

  9. Hydrochloric acid aerosol and gaseous hydrogen chloride partitioning in a cloud contaminated by solid rocket exhaust

    Science.gov (United States)

    Sebacher, D. I.; Bendura, R. J.; Wornom, D. E.

    1980-01-01

    Partitioning of hydrogen chloride between hydrochloric acid aerosol and gaseous HCl in the lower atmosphere was experimentally investigated in a solid rocket exhaust cloud diluted with humid ambient air. Airborne measurements were obtained of gaseous HCl, total HCl, relative humidity and temperature to evaluate the conditions under which aerosol formation occurs in the troposphere in the presence of hygroscopic HCl vapor. Equilibrium predictions of HCl aerosol formation accurately predict the measured HCl partitioning over a range of total HCl concentrations from 0.6 to 16 ppm.

  10. Test results from a simple, low-cost, pressure-fed liquid hydrogen/liquid oxygen rocket combustor

    Science.gov (United States)

    Dressler, G. A.; Stoddard, F. J.; Gavitt, K. R.; Klem, M. D.

    1993-01-01

    A simple, low-cost rocket engine was designed, fabricated, and successfully hot fire tested over a wide range of interface conditions and operating parameters. The engine used low enthalpy hydrogen (45 to 70 R, 200 to 390 psia) and oxygen (139 to 163 R, 210 to 480 psia) propellants pressure-fed directly from facility cryogenic tanks. The engine demonstrated excellent performance, with 97% average combustion efficiency, and absence of combustion instabilities. Engine design chamber pressure was 300 psia, yielding about 16,500 pounds thrust at sea level with a 3:1 expansion ration test nozzle. The engine used a fixed-element injector based on TRW's unique coaxial pintle design, but was operated at 60%, 80%, and 100% thrust levels by throttling facility propellant valves. The engine was tested at propellant mixture ratios (O/F) from 5.8 to 8.4; design O/F was 6.6. To document combustion stability, in five tests RDX explosive pulse guns were detonated in radial and tangential directions across the combustion chamber during steady-state operation. The largest disturbance consisted of simultaneous detonation of a 20-grain radial gun and a 40-grain tangential gun. In no case was an instability, either feed system mode or chamber acoustic mode, excited. High-frequency piezoelectric pressure transducers documented stable recovery from disturbance overpressures within 40 milliseconds of peak pressure. A total of 67 firing tests, accumulating 149 seconds of firing time above 10% P(sub c), were performed. Since parametric testing required run durations of only 2 to 3 seconds, a heat sink combustion chamber was employed for most runs. To evaluate the feasibility of a low-cost ablative system for a flight engine design, one 20-second continuous firing was conducted with a silicone rubber chamber/throat/nozzle liner cast in one piece directly into the engine. The ablative engine operated at the equivalent of 309 seconds sea level specific impulse, when adjusted to a 98% efficient

  11. Test results from a simple, low-cost, pressure-fed liquid hydrogen/liquid oxygen rocket combustor

    Science.gov (United States)

    Dressler, G. A.; Stoddard, F. J.; Gavitt, K. R.; Klem, M. D.

    1993-11-01

    A simple, low-cost rocket engine was designed, fabricated, and successfully hot fire tested over a wide range of interface conditions and operating parameters. The engine used low enthalpy hydrogen (45 to 70 R, 200 to 390 psia) and oxygen (139 to 163 R, 210 to 480 psia) propellants pressure-fed directly from facility cryogenic tanks. The engine demonstrated excellent performance, with 97% average combustion efficiency, and absence of combustion instabilities. Engine design chamber pressure was 300 psia, yielding about 16,500 pounds thrust at sea level with a 3:1 expansion ration test nozzle. The engine used a fixed-element injector based on TRW's unique coaxial pintle design, but was operated at 60%, 80%, and 100% thrust levels by throttling facility propellant valves. The engine was tested at propellant mixture ratios (O/F) from 5.8 to 8.4; design O/F was 6.6. To document combustion stability, in five tests RDX explosive pulse guns were detonated in radial and tangential directions across the combustion chamber during steady-state operation. The largest disturbance consisted of simultaneous detonation of a 20-grain radial gun and a 40-grain tangential gun. In no case was an instability, either feed system mode or chamber acoustic mode, excited. High-frequency piezoelectric pressure transducers documented stable recovery from disturbance overpressures within 40 milliseconds of peak pressure. A total of 67 firing tests, accumulating 149 seconds of firing time above 10% P(sub c), were performed. Since parametric testing required run durations of only 2 to 3 seconds, a heat sink combustion chamber was employed for most runs. To evaluate the feasibility of a low-cost ablative system for a flight engine design, one 20-second continuous firing was conducted with a silicone rubber chamber/throat/nozzle liner cast in one piece directly into the engine. The ablative engine operated at the equivalent of 309 seconds sea level specific impulse, when adjusted to a 98% efficient

  12. Lift-Off Acoustics Prediction of Clustered Rocket Engines in the Near Field

    Science.gov (United States)

    Vu, Bruce; Plotkin, Ken

    2010-01-01

    This slide presentation presents a method of predicting acoustics during lift-off of the clustered rocket engines in the near field. Included is a definition of the near field, and the use of deflectors and shielding. There is discussion about the use of PAD, a software system designed to calculate the acoustic levels from the lift of of clustered rocket enginee, including updates to extend the calculation to directivity, water suppression, and clustered nozzles.

  13. Two-phase flow characteristics of liquid oxygen flow in low pressure liquid rocket engine

    Energy Technology Data Exchange (ETDEWEB)

    Namkyung Cho; Youngmog Kim [Korea Aerospace Research Inst., Control Systems Dept., Daejeon (Korea); Seunghan Kim [Korea Aerospace Research Inst., Engine Dept., Daejeon (Korea); Sangkwon Jeong; Jeheon Jung [Korea Advanced Inst. of Science and Technology, Dept. of Mechanical Engineering, Daejeon (Korea)

    2004-08-01

    In most cryogenic liquid rocket engines, liquid oxygen manifold and injector are not thermally insulated from room temperature environment for the purpose of reducing system complexity and weight. This feature of cryogenic liquid supply system results in the situation that liquid oxygen flow is vaporized especially in the vicinity of the manifold and the injector wall. The transient two-phase flow tendency is severe for low combustion pressure rocket engine without using turbo-pump. This paper focuses on the two-phase flow phenomena of liquid oxygen in low combustion pressure rocket engine. The KSR-III (Korea Sounding Rocket) engine test data is thoroughly analyzed to estimate the vapor fraction of liquid oxygen flow near the engine manifold and the injector. During the cold flow and the combustion tests of the KSR-III Engine, the static and dynamic pressures are measured at the engine inlet, the liquid oxygen manifold and the combustion chamber. The manifold outer wall and the inner wall temperatures are also measured. In this paper, we present the experimental investigation on the vapor generation, the vapor mass fraction, and the boiling characteristics of the liquid oxygen flow in the engine manifold and injector. (Author)

  14. Technique for the optimization of the powerhead configuration and performance of liquid rocket engines

    Science.gov (United States)

    St. Germain, Brad David

    The development and optimization of liquid rocket engines is an integral part of space vehicle design, since most Earth-to-orbit launch vehicles to date have used liquid rockets as their main propulsion system. Rocket engine design tools range in fidelity from very simple conceptual level tools to full computational fluid dynamics (CFD) simulations. The level of fidelity of interest in this research is a design tool that determines engine thrust and specific impulse as well as models the powerhead of the engine. This is the highest level of fidelity applicable to a conceptual level design environment where faster running analyses are desired. The optimization of liquid rocket engines using a powerhead analysis tool is a difficult problem, because it involves both continuous and discrete inputs as well as a nonlinear design space. Example continuous inputs are the main combustion chamber pressure, nozzle area ratio, engine mixture ratio, and desired thrust. Example discrete variable inputs are the engine cycle (staged-combustion, gas generator, etc.), fuel/oxidizer combination, and engine material choices. Nonlinear optimization problems involving both continuous and discrete inputs are referred to as Mixed-Integer Nonlinear Programming (MINLP) problems. Many methods exist in literature for solving MINLP problems; however none are applicable for this research. All of the existing MINLP methods require the relaxation of the discrete variables as part of their analysis procedure. This means that the discrete choices must be evaluated at non-discrete values. This is not possible with an engine powerhead design code. Therefore, a new optimization method was developed that uses modified response surface equations to provide lower bounds of the continuous design space for each unique discrete variable combination. These lower bounds are then used to efficiently solve the optimization problem. The new optimization procedure was used to find optimal rocket engine designs

  15. Combustion and Magnetohydrodynamic Processes in Advanced Pulse Detonation Rocket Engines

    Science.gov (United States)

    2012-10-01

    2.22)) Θ Characteristic Temperature 0 Permittivity of free space μ0 Permeability of free space ()i i th numerical grid cell q (. . . , qi−1, qi, qi...the rapid burning of solid fuel composed of a mixture of a fuel and oxidizer. Gun powder emerged in China around AD 850 as the result of accidental...the advancement of liquid fueled rockets and in 1919 published, “A Method of Reaching Extreme Altitudes”, which not only provided the mathematical

  16. Lagrangian modeling of turbulent spray combustion: application to rocket engines cryogenic conditions

    Science.gov (United States)

    Izard, J.-F.; Mura, A.

    2011-10-01

    The present work is concerned with the application of a turbulent two-phase flow combustion model to a spray flame of Liquid Oxygen (LOx) and Gaseous Hydrogen (GH2). The proposed strategy relies on a joint Eulerian-Lagrangian framework. The Probability Density Function (PDF) that characterizes the liquid phase is evaluated by simulating the Williams spray equation [1] thanks to the semifluid approach introduced in [2]. The Lagrangian approach provides the classical exchange terms with the gaseous phase and, especially, several vaporization source terms. They are required to describe turbulent combustion but difficult to evaluate from the Eulerian point of view. The turbulent combustion model retained here relies on the consideration of the mixture fraction to evaluate the local fuel-to-oxidizer ratio, and the oxygen mass fraction to follow the deviations from chemical equilibrium. The difficulty associated with the estimation of a joint scalar PDF is circumvented by invoking the sudden chemistry hypothesis [3]. In this manner, the problem reduces to the estimation of the mixture fraction PDF, but with the influence of the terms related to vaporization that are the source of additional fluctuations of composition. Following the early proposal of [4], these terms are easily obtained from the Lagrangian framework adopted to describe the two-phase flows. The resulting computational model is applied to the numerical simulation of LOx-GH2 spray flames. The test case (Mascotte) is representative of combustion in rocket engine conditions. The results of numerical simulations display a satisfactory agreement with available experimental data.

  17. Identification of Noise Sources During Rocket Engine Test Firings and a Rocket Launch Using a Microphone Phased-Array

    Science.gov (United States)

    Panda, Jayanta; Mosher, Robert N.; Porter, Barry J.

    2013-01-01

    A 70 microphone, 10-foot by 10-foot, microphone phased array was built for use in the harsh environment of rocket launches. The array was setup at NASA Wallops launch pad 0A during a static test firing of Orbital Sciences' Antares engines, and again during the first launch of the Antares vehicle. It was placed 400 feet away from the pad, and was hoisted on a scissor lift 40 feet above ground. The data sets provided unprecedented insight into rocket noise sources. The duct exit was found to be the primary source during the static test firing; the large amount of water injected beneath the nozzle exit and inside the plume duct quenched all other sources. The maps of the noise sources during launch were found to be time-dependent. As the engines came to full power and became louder, the primary source switched from the duct inlet to the duct exit. Further elevation of the vehicle caused spilling of the hot plume, resulting in a distributed noise map covering most of the pad. As the entire plume emerged from the duct, and the ondeck water system came to full power, the plume itself became the loudest noise source. These maps of the noise sources provide vital insight for optimization of sound suppression systems for future Antares launches.

  18. Rocket Science: The Shuttle's Main Engines, though Old, Are not Forgotten in the New Exploration Initiative

    Science.gov (United States)

    Covault, Craig

    2005-01-01

    The Space Shuttle Main Engine (SSME), developed 30 years ago, remains a strong candidate for use in the new Exploration Initiative as part of a shuttle-derived heavy-lift expendable booster. This is because the Boeing-Rocket- dyne man-rated SSME remains the most highly efficient liquid rocket engine ever developed. There are only enough parts for 12-15 existing SSMEs, however, so one NASA option is to reinitiate SSME production to use it as a throw-away, as opposed to a reusable, powerplant for NASA s new heavy-lift booster.

  19. LOX/Methane Regeneratively-Cooled Rocket Engine Development Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Design, build, and test a 5,000 lbf thrust regeneratively cooled combustion chamber at JSC for a low pressure liquid oxygen/methane engine. The engine demonstrates...

  20. SMC Standard: Evaluation and Test Requirements for Liquid Rocket Engines

    Science.gov (United States)

    2017-07-26

    and procedures, and verify performance of engine system passive and active thermal control (including chilldown, warming purges, heaters, etc...qualification activity shall use a minimum number of unique engine samples that are of the flight design, or are structurally and functionally...samples are included in the total count of verification engine samples. [4.3.1-3] All engines used for verification activity shall include the same

  1. Coolant-side heat-transfer rates for a hydrogen-oxygen rocket and a new technique for data correlation

    Science.gov (United States)

    Schacht, R. L.; Quentmeyer, R. J.

    1973-01-01

    An experimental investigation was conducted to determine the coolant-side, heat transfer coefficients for a liquid cooled, hydrogen-oxygen rocket thrust chamber. Heat transfer rates were determined from measurements of local hot gas wall temperature, local coolant temperature, and local coolant pressure. A correlation incorporating an integration technique for the transport properties needed near the pseudocritical temperature of liquid hydrogen gives a satisfactory prediction of hot gas wall temperatures.

  2. Hydrogen storage in engineered carbon nanospaces.

    Science.gov (United States)

    Burress, Jacob; Kraus, Michael; Beckner, Matt; Cepel, Raina; Suppes, Galen; Wexler, Carlos; Pfeifer, Peter

    2009-05-20

    It is shown how appropriately engineered nanoporous carbons provide materials for reversible hydrogen storage, based on physisorption, with exceptional storage capacities (approximately 80 g H2/kg carbon, approximately 50 g H2/liter carbon, at 50 bar and 77 K). Nanopores generate high storage capacities (a) by having high surface area to volume ratios, and (b) by hosting deep potential wells through overlapping substrate potentials from opposite pore walls, giving rise to a binding energy nearly twice the binding energy in wide pores. Experimental case studies are presented with surface areas as high as 3100 m(2) g(-1), in which 40% of all surface sites reside in pores of width approximately 0.7 nm and binding energy approximately 9 kJ mol(-1), and 60% of sites in pores of width>1.0 nm and binding energy approximately 5 kJ mol(-1). The findings, including the prevalence of just two distinct binding energies, are in excellent agreement with results from molecular dynamics simulations. It is also shown, from statistical mechanical models, that one can experimentally distinguish between the situation in which molecules do (mobile adsorption) and do not (localized adsorption) move parallel to the surface, how such lateral dynamics affects the hydrogen storage capacity, and how the two situations are controlled by the vibrational frequencies of adsorbed hydrogen molecules parallel and perpendicular to the surface: in the samples presented, adsorption is mobile at 293 K, and localized at 77 K. These findings make a strong case for it being possible to significantly increase hydrogen storage capacities in nanoporous carbons by suitable engineering of the nanopore space.

  3. Hypergolic bipropellant spray combustion and flow modelling in rocket engines

    Science.gov (United States)

    Larosiliere, Louis M.; Litchford, Ron J.; Jeng, San-Mou

    1990-01-01

    A predictive tool for hypergolic bipropellant spray combustion and flow evolution in small rocket combustion chambers is described. It encompasses a computational technique for the gas-phase governing equations, a discrete particle method for liquid bipropellant sprays, and constitutive models for combustion chemistry, interphase exchanges, and unlike impinging hypergolic spray interactions. Emphasis is placed on the phenomenological modeling of the hypergolic liquid bipropellant gasification processes. Sample computations with the N2H4-N2O4 propellant system are given in order to show some of the capabilities and inadequacies of this tool.

  4. Preliminary Thermo-hydraulic Core Design Analysis of Korea Advanced Nuclear Thermal Engine Rocket for Space Application

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Seung Hyun; Lee, Jeong Ik; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2014-05-15

    Nclear rockets improve the propellant efficiency more than twice compared to CRs and thus significantly reduce the propellant requirement. The superior efficiency of nuclear rockets is due to the combination of the huge energy density and a single low molecular weight propellant utilization. Nuclear Thermal Rockets (NTRs) are particularly suitable for manned missions to Mars because it satisfies a relatively high thrust as well as a high propellant efficiency. NTRs use thermal energy released from a nuclear fission reactor to heat a single low molecular weight propellant, i. e., Hydrogen (H{sub 2}) and then exhausted the extremely heated propellant through a thermodynamic nozzle to produce thrust. A propellant efficiency parameter of rocket engines is specific impulse (I{sub sp}) which represents the ratio of the thrust over the rate of propellant consumption. The difference of I{sub sp} makes over three times propellant savings of NTRs for a manned Mars mission compared to CRs. NTRs can also be configured to operate bimodally by converting the surplus nuclear energy to auxiliary electric power required for the operation of a spacecraft. Moreover, the concept and technology of NTRs are very simple, already proven, and safe. Thus, NTRs can be applied to various space missions such as solar system exploration, International Space Station (ISS) transport support, Near Earth Objects (NEOs) interception, etc. Nuclear propulsion is the most promising and viable option to achieve challenging deep space missions. Particularly, the attractions of a NTR include excellent thrust and propellant efficiency, bimodal capability, proven technology, and safe and reliable performance. The ROK has also begun the research for space nuclear systems as a volunteer of the international space race and a major world nuclear energy country. KANUTER is one of the advanced NTR engines currently under development at KAIST. This bimodal engine is operated in two modes of propulsion with 100 MW

  5. Verification of Model of Calculation of Intra-Chamber Parameters In Hybrid Solid-Propellant Rocket Engines

    Directory of Open Access Journals (Sweden)

    Zhukov Ilya S.

    2016-01-01

    Full Text Available On the basis of obtained analytical estimate of characteristics of hybrid solid-propellant rocket engine verification of earlier developed physical and mathematical model of processes in a hybrid solid-propellant rocket engine for quasi-steady-state flow regime was performed. Comparative analysis of calculated and analytical data indicated satisfactory comparability of simulation results.

  6. Radiological effluents released from nuclear rocket and ramjet engine tests at the Nevada Test Site 1959 through 1969: Fact Book

    Energy Technology Data Exchange (ETDEWEB)

    Friesen, H.N.

    1995-06-01

    Nuclear rocket and ramjet engine tests were conducted on the Nevada Test Site (NTS) in Area 25 and Area 26, about 80 miles northwest of Las Vegas, Nevada, from July 1959 through September 1969. This document presents a brief history of the nuclear rocket engine tests, information on the off-site radiological monitoring, and descriptions of the tests.

  7. METHOD OF HYDROGEN FEEDING FOR AUTOMOTIVE ENGINE SUPPLY

    Directory of Open Access Journals (Sweden)

    F. Abramchuk

    2010-01-01

    Full Text Available On basis of analysis of various methods of hydrogen feeding for automotive engine supply methods of multipoint hydrogen distribution with microprocessor-based control are proposed.

  8. Hydrogen engine performance analysis project. Second annual report

    Energy Technology Data Exchange (ETDEWEB)

    Adt, Jr., R. R.; Swain, M. R.; Pappas, J. M.

    1980-01-01

    Progress in a 3 year research program to evaluate the performance and emission characteristics of hydrogen-fueled internal combustion engines is reported. Fifteen hydrogen engine configurations will be subjected to performance and emissions characterization tests. During the first two years, baseline data for throttled and unthrottled, carburetted and timed hydrogen induction, Pre IVC hydrogen-fueled engine configurations, with and without exhaust gas recirculation (EGR) and water injection, were obtained. These data, along with descriptions of the test engine and its components, the test apparatus, experimental techniques, experiments performed and the results obtained, are given. Analyses of other hydrogen-engine project data are also presented and compared with the results of the present effort. The unthrottled engine vis-a-vis the throttled engine is found, in general, to exhibit higher brake thermal efficiency. The unthrottled engine also yields lower NO/sub x/ emissions, which were found to be a strong function of fuel-air equivalence ratio. (LCL)

  9. Hydrogen engines based on liquid fuels, a review

    Science.gov (United States)

    Houseman, J.; Voecks, G. E.

    1981-01-01

    The concept of storing hydrogen as part of a liquid fuel, such as gasoline or methanol, and subsequent onboard generation of the hydrogen from such liquids, is reviewed. Hydrogen generation processes, such as steam reforming, partial oxidation, and thermal decomposition are evaluated in terms of theoretical potential and practical limitations, and a summary is presented on the major experimental work on conversion of gasoline and methanol. Results of experiments indicate that onboard hydrogen generation from methanol is technically feasible and will yield substantial improvements in fuel economy and emissions, especially if methanol decomposition is brought about by the use of engine exhaust heat; e.g., a methanol decomposition reactor of 3.8 provides hydrogen-rich gas for a 4 cylinder engine (1.952), and 80% of the methanol is converted, engine exhaust gas being the only heat supply. A preliminary outline of the development of a methanol-based hydrogen engine and a straight hydrogen engine is presented.

  10. JANNAF "Test and Evaluation Guidelines for Liquid Rocket Engines": Status and Application

    Science.gov (United States)

    Parkinson, Douglas; VanLerberghe, Wayne M.; Rahman, Shamim A.

    2017-01-01

    For many decades, the U.S. rocket propulsion industrial base has performed remarkably in developing complex liquid rocket engines that can propel critical payloads into service for the nation, as well as transport people and hardware for missions that open the frontiers of space exploration for humanity. This has been possible only at considerable expense given the lack of detailed guidance that captures the essence of successful practices and knowledge accumulated over five decades of liquid rocket engine development. In an effort to provide benchmarks and guidance for the next generation of rocket engineers, the Joint Army Navy NASA Air Force (JANNAF) Interagency Propulsion Committee published a liquid rocket engine (LRE) test and evaluation (T&E) guideline document in 2012 focusing on the development challenges and test verification considerations for liquid rocket engine systems. This document has been well received and applied by many current LRE developers as a benchmark and guidance tool, both for government-driven applications as well as for fully commercial ventures. The USAF Space and Missile Systems Center (SMC) has taken an additional near-term step and is directing activity to adapt and augment the content from the JANNAF LRE T&E guideline into a standard for potential application to future USAF requests for proposals for LRE development initiatives and launch vehicles for national security missions. A draft of this standard was already sent out for review and comment, and is intended to be formally approved and released towards the end of 2017. The acceptance and use of the LRE T&E guideline is possible through broad government and industry participation in the JANNAF liquid propulsion committee and associated panels. The sponsoring JANNAF community is expanding upon this initial baseline version and delving into further critical development aspects of liquid rocket propulsion testing at the integrated stage level as well as engine component level, in

  11. High Frequency Combustion Instabilities of LOx/CH4 Spray Flames in Rocket Engine Combustion Chambers

    NARCIS (Netherlands)

    Sliphorst, M.

    2011-01-01

    Ever since the early stages of space transportation in the 1940’s, and the related liquid propellant rocket engine development, combustion instability has been a major issue. High frequency combustion instability (HFCI) is the interaction between combustion and the acoustic field in the combustion

  12. Design and analysis of a single stage to orbit nuclear thermal rocket reactor engine

    Energy Technology Data Exchange (ETDEWEB)

    Labib, Satira, E-mail: Satira.Labib@duke-energy.com; King, Jeffrey, E-mail: kingjc@mines.edu

    2015-06-15

    Graphical abstract: - Highlights: • Three NTR reactors are optimized for the single stage launch of 1–15 MT payloads. • The proposed rocket engines have specific impulses in excess of 700 s. • Reactivity and submersion criticality requirements are satisfied for each reactor. - Abstract: Recent advances in the development of high power density fuel materials have renewed interest in nuclear thermal rockets (NTRs) as a viable propulsion technology for future space exploration. This paper describes the design of three NTR reactor engines designed for the single stage to orbit launch of payloads from 1 to 15 metric tons. Thermal hydraulic and rocket engine analyses indicate that the proposed rocket engines are able to reach specific impulses in excess of 800 s. Neutronics analyses performed using MCNP5 demonstrate that the hot excess reactivity, shutdown margin, and submersion criticality requirements are satisfied for each NTR reactor. The reactors each consist of a 40 cm diameter core packed with hexagonal tungsten cermet fuel elements. The core is surrounded by radial and axial beryllium reflectors and eight boron carbide control drums. The 40 cm long reactor meets the submersion criticality requirements (a shutdown margin of at least $1 subcritical in all submersion scenarios) with no further modifications. The 80 and 120 cm long reactors include small amounts of gadolinium nitride as a spectral shift absorber to keep them subcritical upon submersion in seawater or wet sand following a launch abort.

  13. Solution-limited time stepping method and numerical simulation of single-element rocket engine combustor

    Science.gov (United States)

    Lian, Chenzhou

    The focus of the research is to gain a better understanding of the mixing and combustion of propellants in a confined single element rocket engine combustor. The approach taken is to use the unsteady computational simulations of both liquid and gaseous oxygen reacting with gaseous hydrogen to study the effects of transient processes, recirculation regions and density variations under supercritical conditions. The physics of combustion involve intimate coupling between fluid dynamics, chemical kinetics and intense energy release and take place over an exceptionally wide range of scales. In the face of these monumental challenges, it remains the engineer's task to find acceptable simulation approach and reliable CFD algorithm for combustion simulations. To provide the computational robustness to allow detailed analyses of such complex problems, we start by investigating a method for enhancing the reliability of implicit computational algorithms and decreasing their sensitivity to initial conditions without adversely impacting their efficiency. Efficient convergence is maintained by specifying a large global CFL number while reliability is improved by limiting the local CFL number such that the solution change in any cell is less than a specified tolerance. The magnitude of the solution change is estimated from the calculated residual in a manner that requires negligible computational time. The method precludes unphysical excursions in Newton-like iterations in highly non-linear regions where Jacobians are changing rapidly as well as non-physical results during the computation. The method is tested against a series of problems to identify its characteristics and to verify the approach. The results reveal a substantial improvement in convergence reliability of implicit CFD applications that enables computations starting from simple initial conditions. The method is applied in the unsteady combustion simulations and allows long time running of the code without user

  14. An Investigation of High-frequency Combustion Oscillations in Liquid-propellant Rocket Engines

    Science.gov (United States)

    Mantler, Raymond L; Tischler, Adelbert O; Massa, Rudolph V

    1953-01-01

    An experimental investigation of high-frequency combustion oscillations (screaming) was conducted with a 100-pound-thrust acid-hydrocarbon rocket engine and a 500-pound-thrust oxygen-fuel rocket engine. The oscillation frequencies could be correlated as a linear function of the parameter C/L, where C is the experimentally measured characteristic velocity and L is the combustion-chamber length. The tendency of the engines to scream increased as chamber length was increased. With engine configurations that normally had a low efficiency, screaming resulted in increased performance; at the same time, a five to tenfold increase in heat-transfer rate occurred. It was possible, however, to achieve good performance without screaming.

  15. Test and Evaluation Guideline for Liquid Rocket Engines

    Science.gov (United States)

    2011-10-11

    Engine Health Management ( EHM ) System Validation ............................................ 43  4.6  OPERATIONS... EHM ) System Validation  The engine control system communicates with the vehicle, accepts commands, transmits data, directs  engine operational...are common approaches for flight software and electronic hardware integration.  Demonstrate and validate that the  EHM  system can correctly detect and

  16. Lightweight Exit Cone for Liquid Rocket Engines Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Pratt and Whitney Rocketdyne (PWR) J-2X engine will power the upper stage of the Ares I and the earth departure stage (EDS) of the Ares V, which will enable...

  17. Rocket Engine Health Management: Early Definition of Critical Flight Measurements

    Science.gov (United States)

    Christenson, Rick L.; Nelson, Michael A.; Butas, John P.

    2003-01-01

    The NASA led Space Launch Initiative (SLI) program has established key requirements related to safety, reliability, launch availability and operations cost to be met by the next generation of reusable launch vehicles. Key to meeting these requirements will be an integrated vehicle health management ( M) system that includes sensors, harnesses, software, memory, and processors. Such a system must be integrated across all the vehicle subsystems and meet component, subsystem, and system requirements relative to fault detection, fault isolation, and false alarm rate. The purpose of this activity is to evolve techniques for defining critical flight engine system measurements-early within the definition of an engine health management system (EHMS). Two approaches, performance-based and failure mode-based, are integrated to provide a proposed set of measurements to be collected. This integrated approach is applied to MSFC s MC-1 engine. Early identification of measurements supports early identification of candidate sensor systems whose design and impacts to the engine components must be considered in engine design.

  18. Development and Hotfire Testing of Additively Manufactured Copper Combustion Chambers for Liquid Rocket Engine Applications

    Science.gov (United States)

    Gradl, Paul R.; Greene, Sandy; Protz, Chris

    2017-01-01

    NASA and industry partners are working towards fabrication process development to reduce costs and schedules associated with manufacturing liquid rocket engine components with the goal of reducing overall mission costs. One such technique being evaluated is powder-bed fusion or selective laser melting (SLM), commonly referred to as additive manufacturing (AM). The NASA Low Cost Upper Stage Propulsion (LCUSP) program was designed to develop processes and material characterization for GRCop-84 (a NASA Glenn Research Center-developed copper, chrome, niobium alloy) commensurate with powder bed AM, evaluate bimetallic deposition, and complete testing of a full scale combustion chamber. As part of this development, the process has been transferred to industry partners to enable a long-term supply chain of monolithic copper combustion chambers. To advance the processes further and allow for optimization with multiple materials, NASA is also investigating the feasibility of bimetallic AM chambers. In addition to the LCUSP program, NASA’s Marshall Space Flight Center (MSFC) has completed a series of development programs and hot-fire tests to demonstrate SLM GRCop-84 and other AM techniques. MSFC’s efforts include a 4,000 pounds-force thrust liquid oxygen/methane (LOX/CH4) combustion chamber. Small thrust chambers for 1,200 pounds-force LOX/hydrogen (H2) applications have also been designed and fabricated with SLM GRCop-84. Similar chambers have also completed development with an Inconel 625 jacket bonded to the GRCop-84 material, evaluating direct metal deposition (DMD) laser- and arc-based techniques. The same technologies for these lower thrust applications are being applied to 25,000-35,000 pounds-force main combustion chamber (MCC) designs. This paper describes the design, development, manufacturing and testing of these numerous combustion chambers, and the associated lessons learned throughout their design and development processes.

  19. Numerical Simulation of Jet Streams in Objects of Space Rocket Engineering

    Science.gov (United States)

    Timoshenko, V. I.; Belotserkovets, I. S.

    The problems of numerical simulation of different jet streams in space rocket engineering objects and their elements are considered. The capabilities of the computing programs and computational techniques developed at the Institute of Technical Mechanics of the N.A.S. of Ukraine are discussed. The following aspects of jet stream problems are described: interaction of subsonic and supersonic jet streams with supersonic and subsonic boundless flows, with streams in pipes or channels, including jet streams in the launcher container and around the fuel pylons of a hypersonic flight vehicle with supersonic burning combustion chamber; the computation of single and composite supersonic jets in rocket propulsion systems and their interaction with surfaces; estimation of parameters in asymmetrical separating zones behind the bottom of a rocket with a working jet.

  20. Artificial intelligence techniques for ground test monitoring of rocket engines

    Science.gov (United States)

    Ali, Moonis; Gupta, U. K.

    1990-01-01

    An expert system is being developed which can detect anomalies in Space Shuttle Main Engine (SSME) sensor data significantly earlier than the redline algorithm currently in use. The training of such an expert system focuses on two approaches which are based on low frequency and high frequency analyses of sensor data. Both approaches are being tested on data from SSME tests and their results compared with the findings of NASA and Rocketdyne experts. Prototype implementations have detected the presence of anomalies earlier than the redline algorithms that are in use currently. It therefore appears that these approaches have the potential of detecting anomalies early eneough to shut down the engine or take other corrective action before severe damage to the engine occurs.

  1. Thermal modelling of various thermal barrier coatings in a high heat flux rocket engine

    Science.gov (United States)

    Nesbitt, James A.

    1989-01-01

    Traditional Air Plasma Sprayed (APS) ZrO2-Y2O3 Thermal Barrier Coatings (TBC's) and Low Pressure Plasma Sprayed (LPPS) ZrO2-Y2O3/Ni-Cr-Al-Y cermet coatings were tested in a H2/O2 rocked engine. The traditional ZrO2-Y2O3 (TBC's) showed considerable metal temperature reductions during testing in the hydrogen-rich environment. A thermal model was developed to predict the thermal response of the tubes with the various coatings. Good agreement was observed between predicted temperatures and measured temperatures at the inner wall of the tube and in the metal near the coating/metal interface. The thermal model was also used to examine the effect of the differences in the reported values of the thermal conductivity of plasma sprayed ZrO2-Y2O3 ceramic coatings, the effect of 100 micron (0.004 in.) thick metallic bond coat, the effect of tangential heat transfer around the tube, and the effect or radiation from the surface of the ceramic coating. It was shown that for the short duration testing in the rocket engine, the most important of these considerations was the effect of the uncertainty in the thermal conductivity of temperatures (greater than 100 C) predicted in the tube. The thermal model was also used to predict the thermal response of the coated rod in order to quantify the difference in the metal temperatures between the two substrate geometries and to explain the previously-observed increased life of coatings on rods over that on tubes. A thermal model was also developed to predict heat transfer to the leading edge of High Pressure Fuel Turbopump (HPFTP) blades during start-up of the space shuttle main engines. The ability of various TBC's to reduce metal temperatures during the two thermal excursions occurring on start-up was predicted. Temperature reductions of 150 to 470 C were predicted for 165 micron (0.0065 in.) coatings for the greater of the two thermal excursions.

  2. Affordable Development and Demonstration of a Small Nuclear Thermal Rocket (NTR) Engine and Stage: How Small Is Big Enough?

    Science.gov (United States)

    Borowski, Stanley K.; Sefcik, Robert J.; Fittje, James E.; McCurdy, David R.; Qualls, Arthur L.; Schnitzler, Bruce G.; Werner, James E.; Weitzberg, Abraham; Joyner, Claude R.

    2016-01-01

    89-centimeters) -long FE, the SNRE's larger diameter core contains approximately 300 more FEs needed to produce an additional 210 thermal megawatts of power. To reduce the cost of the FTD mission, a simple one-burn lunar flyby mission was considered to reduce the liquid hydrogen (LH2) propellant loading, the stage size and complexity. Use of existing and flight proven liquid rocket and stage hardware (e.g., from the RL10B-2 engine and Delta Cryogenic Second Stage) was also maximized to further aid affordability. This paper examines the pros and cons of using these two small engine options, including their potential to support future human exploration missions to the Moon, near Earth asteroids (NEA), and Mars, and recommends a preferred size. It also provides a preliminary assessment of the key activities, development options, and schedule required to affordably build, ground test and fly a small NTR engine and stage within a 10-year timeframe.

  3. Signal Processing Methods for Liquid Rocket Engine Combustion Spontaneous Stability and Rough Combustion Assessments

    Science.gov (United States)

    Kenny, R. Jeremy; Casiano, Matthew; Fischbach, Sean; Hulka, James R.

    2012-01-01

    Liquid rocket engine combustion stability assessments are traditionally broken into three categories: dynamic stability, spontaneous stability, and rough combustion. This work focuses on comparing the spontaneous stability and rough combustion assessments for several liquid engine programs. The techniques used are those developed at Marshall Space Flight Center (MSFC) for the J-2X Workhorse Gas Generator program. Stability assessment data from the Integrated Powerhead Demonstrator (IPD), FASTRAC, and Common Extensible Cryogenic Engine (CECE) programs are compared against previously processed J-2X Gas Generator data. Prior metrics for spontaneous stability assessments are updated based on the compilation of all data sets.

  4. Prediction of high frequency combustion instability in liquid propellant rocket engines

    Science.gov (United States)

    Kim, Y. M.; Chen, C. P.; Ziebarth, J. P.; Chen, Y. S.

    1992-01-01

    The present use of a numerical model developed for the prediction of high-frequency combustion stabilities in liquid propellant rocket engines focuses on (1) the overall behavior of nonlinear combustion instabilities (2) the effects of acoustic oscillations on the fuel-droplet vaporization and combustion process in stable and unstable engine operating conditions, oscillating flowfields, and liquid-fuel trajectories during combustion instability, and (3) the effects of such design parameters as inlet boundary conditions, initial spray conditions, and baffle length. The numerical model has yielded predictions of the tangential-mode combustion instability; baffle length and droplet size variations are noted to have significant effects on engine stability.

  5. Dynamic modeling and compensation of fine wire thermocouple based on rocket engine

    Science.gov (United States)

    Xu, Qiang; Liao, Guangxuan

    2001-08-01

    When transient temperature is measured by thermocouples, the result is largely influenced by thermocouple's dynamic performance. This problem is encountered in measuring flame temperature fluctuation by using of fine wire thermocouple. Because the heat transfer coefficient mostly depends upon the gas temperature and flow speed, the time constant of fine wire thermocouple is not equal in different temperature ranges. The time constant calibrated in low temperature is not valid in this kind of measurement. Typically frequency of fluctuation in flame is less than 7KHz. The fine wire thermocouple often has to be compensated to meet this working frequency band. The compensation range is determined by its time constant in high temperature. High temperature step source with sharp rise is needed in dynamic calibrating this kind of fine wire thermocouples. A dynamic calibration system based on a set of rocket engine and different propellant is introduced to study the dynamic performance of the thermocouples. This set of rocket engine is designed to have same nozzle exhaust Mach number. Different engines with different propellant provide different high temperature step sources. Experiment is conducted in rocket engine static state experiment laboratory. The position of thermocouple is determined according to numerical simulation results. Dynamic modeling and compensation methods are introduced to process the calibration results.

  6. Metabolically engineered bacteria for producing hydrogen via fermentation.

    Science.gov (United States)

    Vardar-Schara, Gönül; Maeda, Toshinari; Wood, Thomas K

    2008-03-01

    Hydrogen, the most abundant and lightest element in the universe, has much potential as a future energy source. Hydrogenases catalyse one of the simplest chemical reactions, 2H(+) + 2e(-) ↔ H(2), yet their structure is very complex. Biologically, hydrogen can be produced via photosynthetic or fermentative routes. This review provides an overview of microbial production of hydrogen by fermentation (currently the more favourable route) and focuses on biochemical pathways, theoretical hydrogen yields and hydrogenase structure. In addition, several examples of metabolic engineering to enhance fermentative hydrogen production are presented along with some examples of expression of heterologous hydrogenases for enhanced hydrogen production. © 2007 The Authors.

  7. Hydrogen-Fuel Engine Component Tests Near Completion

    Science.gov (United States)

    2003-01-01

    Gaseous hydrogen is burned off at the E1 Test Stand the night of Oct. 7 during a cold-flow test of the fuel turbopump of the Integrated Powerhead Demonstrator (IPD) at NASA Stennis Space Center (SSC). The gaseous hydrogen spins the pump's turbine during the test, which was conducted to verify the pump's performance. Engineers plan one more test before sending the pump to The Boeing Co. for inspection. It will then be returned to SSC for engine system assembly. The IPD is the first reusable hydrogen-fueled advanced engine in development since the Space Shuttle Main Engine.

  8. Damage-mitigating control of a reusable rocket engine for high performance and extended life

    Science.gov (United States)

    Ray, Asok; Dai, Xiaowen

    1995-01-01

    The goal of damage mitigating control in reusable rocket engines is to achieve high performance with increased durability of mechanical structures such that functional lives of the critical components are increased. The major benefit is an increase in structural durability with no significant loss of performance. This report investigates the feasibility of damage mitigating control of reusable rocket engines. Phenomenological models of creep and thermo-mechanical fatigue damage have been formulated in the state-variable setting such that these models can be combined with the plant model of a reusable rocket engine, such as the Space Shuttle Main Engine (SSME), for synthesizing an optimal control policy. Specifically, a creep damage model of the main thrust chamber wall is analytically derived based on the theories of sandwich beam and viscoplasticity. This model characterizes progressive bulging-out and incremental thinning of the coolant channel ligament leading to its eventual failure by tensile rupture. The objective is to generate a closed form solution of the wall thin-out phenomenon in real time where the ligament geometry is continuously updated to account for the resulting deformation. The results are in agreement with those obtained from the finite element analyses and experimental observation for both Oxygen Free High Conductivity (OFHC) copper and a copper-zerconium-silver alloy called NARloy-Z. Due to its computational efficiency, this damage model is suitable for on-line applications of life prediction and damage mitigating control, and also permits parametric studies for off-line synthesis of damage mitigating control systems. The results are presented to demonstrate the potential of life extension of reusable rocket engines via damage mitigating control. The control system has also been simulated on a testbed to observe how the damage at different critical points can be traded off without any significant loss of engine performance. The research work

  9. Feasibility Investigation on the Development of a Structural Damage Diagnostic and Monitoring System for Rocket Engines

    Science.gov (United States)

    Shen, Ji Y.; Sharpe, Lonnie, Jr.

    1998-01-01

    The research activity for this project is mainly to investigate the necessity and feasibility to develop a structural health monitoring system for rocket engines, and to carry out a research plan for further development of the system. More than one hundred technical papers have been searched and reviewed during the period. We concluded after this investigation that adding a new module in NASA's existing automated diagnostic system to monitor the healthy condition of rocket engine structures is a crucial task, and it's possible to develop such a system based upon the vibrational-based nondestructive damage assessment techniques. A number of such techniques have been introduced. Their advantages and disadvantages are also discussed. A global research plan has been figured out. As the first step of the overall research plan, a proposal for the next fiscal year has been submitted.

  10. Development of test stand for experimental investigation of chemical and physical phenomena in Liquid Rocket Engine

    Directory of Open Access Journals (Sweden)

    Emerson Andrade Santos

    2011-05-01

    Full Text Available The main objective of this work was to present the specification of an experimental firing test stand for liquid rocket engines (LRE and develop a program for control and acquisition of data. It provides conditions to test rocket engines with thrust from 50 to 100 kgf. A methodology for laboratory work implementation using information technology, which will allow the automatic and remote functioning of the test stand, permits users to input the necessary data to conduct tests safely, achieve accurate measurements and obtain reliable results. The control of propellant mass flow rates by pressure regulators and other system valves, as well as the test stand data acquisition, are carried out automatically through LabVIEW commercial software. The test stand program is a readable, scalable and maintainable code. The test stand design and its development represent the state of art of experimental apparatus in LRE testing.

  11. Application of Background Oriented Schlieren for Altitude Testing of Rocket Engines

    Science.gov (United States)

    Wernet, Mark P.; Stiegemeier, Benjamin R.

    2017-01-01

    A series of experiments was performed to determine the feasibility of using the Background Oriented Schlieren, BOS, flow visualization technique to image a simulated, small, rocket engine, plume under altitude test conditions. Testing was performed at the NASA Glenn Research Centers Altitude Combustion Stand, ACS, using nitrogen as the exhaust gas simulant. Due to limited optical access to the facility test capsule, all of the hardware required to conduct the BOS were located inside the vacuum chamber. During the test series 26 runs were performed using two different nozzle configurations with pressures in the test capsule around 0.3 psia. No problems were encountered during the test series resulting from the optical hardware being located in the test capsule and acceptable resolution images were captured. The test campaign demonstrated the ability of using the BOS technique for small, rocket engine, plume flow visualization during altitude testing.

  12. Signal Processing Methods for Liquid Rocket Engine Combustion Stability Assessments

    Science.gov (United States)

    Kenny, R. Jeremy; Lee, Erik; Hulka, James R.; Casiano, Matthew

    2011-01-01

    The J2X Gas Generator engine design specifications include dynamic, spontaneous, and broadband combustion stability requirements. These requirements are verified empirically based high frequency chamber pressure measurements and analyses. Dynamic stability is determined with the dynamic pressure response due to an artificial perturbation of the combustion chamber pressure (bomb testing), and spontaneous and broadband stability are determined from the dynamic pressure responses during steady operation starting at specified power levels. J2X Workhorse Gas Generator testing included bomb tests with multiple hardware configurations and operating conditions, including a configuration used explicitly for engine verification test series. This work covers signal processing techniques developed at Marshall Space Flight Center (MSFC) to help assess engine design stability requirements. Dynamic stability assessments were performed following both the CPIA 655 guidelines and a MSFC in-house developed statistical-based approach. The statistical approach was developed to better verify when the dynamic pressure amplitudes corresponding to a particular frequency returned back to pre-bomb characteristics. This was accomplished by first determining the statistical characteristics of the pre-bomb dynamic levels. The pre-bomb statistical characterization provided 95% coverage bounds; these bounds were used as a quantitative measure to determine when the post-bomb signal returned to pre-bomb conditions. The time for post-bomb levels to acceptably return to pre-bomb levels was compared to the dominant frequency-dependent time recommended by CPIA 655. Results for multiple test configurations, including stable and unstable configurations, were reviewed. Spontaneous stability was assessed using two processes: 1) characterization of the ratio of the peak response amplitudes to the excited chamber acoustic mode amplitudes and 2) characterization of the variability of the peak response

  13. The review of the IR radiation characteristic of exhaust plume of the liquid rocket engine

    Science.gov (United States)

    Wu, Hanyang; Sheng, Weidong; An, Wei; Zeng, Jian; Yang, Yuanyuan

    2017-02-01

    At present, there are various methods to compute the infrared radiation characteristics of exhaust plume of the liquid rocket engine. Though they are different in computational complexity. Their ideas and methods are alike. This paper focuses on the computation methods of exhaust plume's flow field, spectral parameters and radiation transfer equation. Comparison, analysis and conclusion of these methods are presented. Furthermore, existing problems and improvements of them are proposed as well.

  14. Integrated Ceramic Matrix Composite and Carbon/Carbon Structures for Large Rocket Engine Nozzles and Nozzle Extensions Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Low-cost access to space demands durable, cost-effective, efficient, and low-weight propulsion systems. Key components include rocket engine nozzles and nozzle...

  15. Cu-Cr-Nb-Zr Alloy for Rocket Engines and Other High-Heat- Flux Applications

    Science.gov (United States)

    Ellis, David L.

    2013-01-01

    Rocket-engine main combustion chamber liners are used to contain the burning of fuel and oxidizer and provide a stream of high-velocity gas for propulsion. The liners in engines such as the Space Shuttle Main Engine are regeneratively cooled by flowing fuel, e.g., cryogenic hydrogen, through cooling channels in the back side of the liner. The heat gained by the liner from the flame and compression of the gas in the throat section is transferred to the fuel by the liner. As a result, the liner must either have a very high thermal conductivity or a very high operating temperature. In addition to the large heat flux (>10 MW/sq m), the liners experience a very large thermal gradient, typically more than 500 C over 1 mm. The gradient produces thermally induced stresses and strains that cause low cycle fatigue (LCF). Typically, a liner will experience a strain differential in excess of 1% between the cooling channel and the hot wall. Each time the engine is fired, the liner undergoes an LCF cycle. The number of cycles can be as few as one for an expendable booster engine, to as many as several thousand for a reusable launch vehicle or reaction control system. Finally, the liners undergo creep and a form of mechanical degradation called thermal ratcheting that results in the bowing out of the cooling channel into the combustion chamber, and eventual failure of the liner. GRCop-84, a Cu-Cr-Nb alloy, is generally recognized as the best liner material available at the time of this reporting. The alloy consists of 14% Cr2Nb precipitates in a pure copper matrix. Through experimental work, it has been established that the Zr will not participate in the formation of Laves phase precipitates with Cr and Nb, but will instead react with Cu to form the desired Cu-Zr compounds. It is believed that significant improvements in the mechanical properties of GRCop-84 will be realized by adding Zr. The innovation is a Cu-Cr-Nb-Zr alloy covering the composition range of 0.8 to 8.1 weight

  16. Long-term firing tests of the nozzles of rocket engines made on the basis of carbon composite materials

    Science.gov (United States)

    Gubertov, A. M.; Koshlakov, V. V.; Mironov, V. V.; Rubinskii, V. R.; Pashutov, A. V.; Antipov, Ye. A.; Bratukhin, N. A.; Volkov, N. N.; Volkova, L. I.; Tsatsuev, S. M.; Tlevtsezhev, V. V.

    2012-12-01

    The results of the experimental investigation of the physico-chemical processes of interaction, destruction, and ablation of carbon composite materials and oxidation-protective coatings of nozzles of liquid-propellant rocket engines are presented. The thermally-stressed state of the joint between the nozzle made of composite material and the metallic combustion chamber of the rocket engine under standard operating conditions have been analyzed.

  17. Hydrogen-oxygen powered internal combustion engine

    Science.gov (United States)

    Cameron, H.; Morgan, N.

    1970-01-01

    Hydrogen at 300 psi and oxygen at 800 psi are injected sequentially into the combustion chamber to form hydrogen-rich mixture. This mode of injection eliminates difficulties of preignition, detonation, etc., encountered with carburated, spark-ignited, hydrogen-air mixtures. Ignition at startup is by means of a palladium catalyst.

  18. Paraffin-based hybrid rocket engines applications: A review and a market perspective

    Science.gov (United States)

    Mazzetti, Alessandro; Merotto, Laura; Pinarello, Giordano

    2016-09-01

    Hybrid propulsion technology for aerospace applications has received growing attention in recent years due to its important advantages over competitive solutions. Hybrid rocket engines have a great potential for several aeronautics and aerospace applications because of their safety, reliability, low cost and high performance. As a consequence, this propulsion technology is feasible for a number of innovative missions, including space tourism. On the other hand, hybrid rocket propulsion's main drawback, i.e. the difficulty in reaching high regression rate values using standard fuels, has so far limited the maturity level of this technology. The complex physico-chemical processes involved in hybrid rocket engines combustion are of major importance for engine performance prediction and control. Therefore, further investigation is ongoing in order to achieve a more complete understanding of such phenomena. It is well known that one of the most promising solutions for overcoming hybrid rocket engines performance limits is the use of liquefying fuels. Such fuels can lead to notably increased solid fuel regression rate due to the so-called "entrainment phenomenon". Among liquefying fuels, paraffin-based formulations have great potentials as solid fuels due to their low cost, availability (as they can be derived from industrial waste), low environmental impact and high performance. Despite the vast amount of literature available on this subject, a precise focus on market potential of paraffins for hybrid propulsion aerospace applications is lacking. In this work a review of hybrid rocket engines state of the art was performed, together with a detailed analysis of the possible applications of such a technology. A market study was carried out in order to define the near-future foreseeable development needs for hybrid technology application to the aforementioned missions. Paraffin-based fuels are taken into account as the most promising segment for market development

  19. Metabolic engineering to enhance bacterial hydrogen production

    Science.gov (United States)

    Maeda, Toshinari; Sanchez‐Torres, Viviana; Wood, Thomas K.

    2008-01-01

    Summary Hydrogen fuel is renewable, efficient and clean, and fermentative bacteria hold great promise for its generation. Here we use the isogenic Escherichia coli K‐12 KEIO library to rapidly construct multiple, precise deletions in the E. coli genome to direct the metabolic flux towards hydrogen production. Escherichia coli has three active hydrogenases, and the genes involved in the regulation of the formate hydrogen lyase (FHL) system for synthesizing hydrogen from formate via hydrogenase 3 were also manipulated to enhance hydrogen production. Specifically, we altered regulation of FHL by controlling the regulators HycA and FhlA, removed hydrogen consumption by hydrogenases 1 and 2 via the hyaB and hybC mutations, and re‐directed formate metabolism using the fdnG, fdoG, narG, focA, fnr and focB mutations. The result was a 141‐fold increase in hydrogen production from formate to create a bacterium (BW25113 hyaB hybC hycA fdoG/pCA24N‐FhlA) that produces the largest amount of hydrogen to date and one that achieves the theoretical yield for hydrogen from formate. In addition, the hydrogen yield from glucose was increased by 50%, and there was threefold higher hydrogen production from glucose with this strain. PMID:21261819

  20. Focused RBCC Experiments: Two-Rocket Configuration Experiments and Hydrocarbon/Oxygen Rocket Ejector Experiments

    Science.gov (United States)

    Santoro, Robert J.; Pal, Sibtosh

    2003-01-01

    This addendum report documents the results of two additional efforts for the Rocket Based Combined Cycle (RBCC) rocket-ejector mode research work carried out at the Penn State Propulsion Engineering Research Center in support of NASA s technology development efforts for enabling 3 d generation Reusable Launch Vehicles (RLV). The tasks reported here build on an earlier NASA MSFC funded research program on rocket ejector investigations. The first task investigated the improvements of a gaseous hydrogen/oxygen twin thruster RBCC rocket ejector system over a single rocket system. The second task investigated the performance of a hydrocarbon (liquid JP-7)/gaseous oxygen single thruster rocket-ejector system. To gain a systematic understanding of the rocket-ejector s internal fluid mechanic/combustion phenomena, experiments were conducted with both direct-connect and sea-level static diffusion and afterburning (DAB) configurations for a range of rocket operating conditions. For all experimental conditions, overall system performance was obtained through global measurements of wall static pressure profiles, heat flux profiles and engine thrust. Detailed mixing and combustion information was obtained through Raman spectroscopy measurements of major species (gaseous oxygen, hydrogen, nitrogen and water vapor) for the gaseous hydrogen/oxygen rocket ejector experiments.

  1. Coupled Lagrangian impingement spray model for doublet impinging injectors under liquid rocket engine operating conditions

    Directory of Open Access Journals (Sweden)

    Qiang WEI

    2017-08-01

    Full Text Available To predict the effect of the liquid rocket engine combustion chamber conditions on the impingement spray, the conventional uncoupled spray model for impinging injectors is extended by considering the coupling of the jet impingement process and the ambient gas field. The new coupled model consists of the plain-orifice sub-model, the jet-jet impingement sub-model and the droplet collision sub-model. The parameters of the child droplet are determined with the jet-jet impingement sub-model using correlations about the liquid jet parameters and the chamber conditions. The overall model is benchmarked under various impingement angles, jet momentum and off-center ratios. Agreement with the published experimental data validates the ability of the model to predict the key spray characteristics, such as the mass flux and mixture ratio distributions in quiescent air. Besides, impinging sprays under changing ambient pressure and non-uniform gas flow are investigated to explore the effect of liquid rocket engine chamber conditions. First, a transient impingement spray during engine start-up phase is simulated with prescribed pressure profile. The minimum average droplet diameter is achieved when the orifices work in cavitation state, and is about 30% smaller than the steady single phase state. Second, the effect of non-uniform gas flow produces off-center impingement and the rotated spray fan by 38°. The proposed model suggests more reasonable impingement spray characteristics than the uncoupled one and can be used as the first step in the complex simulation of coupling impingement spray and combustion in liquid rocket engines.

  2. Hydrogen-methane fuel control systems for turbojet engines

    Science.gov (United States)

    Goldsmith, J. S.; Bennett, G. W.

    1973-01-01

    Design, development, and test of a fuel conditioning and control system utilizing liquid methane (natural gas) and liquid hydrogen fuels for operation of a J85 jet engine were performed. The experimental program evaluated the stability and response of an engine fuel control employing liquid pumping of cryogenic fuels, gasification of the fuels at supercritical pressure, and gaseous metering and control. Acceptably stable and responsive control of the engine was demonstrated throughout the sea level power range for liquid gas fuel and up to 88 percent engine speed using liquid hydrogen fuel.

  3. Hydrogen as an Auxiliary Fuel in Compression-Ignition Engines

    Science.gov (United States)

    Gerrish, Harold C; Foster, H

    1936-01-01

    An investigation was made to determine whether a sufficient amount of hydrogen could be efficiently burned in a compression-ignition engine to compensate for the increase of lift of an airship due to the consumption of the fuel oil. The performance of a single-cylinder four-stroke-cycle compression-ignition engine operating on fuel oil alone was compared with its performance when various quantities of hydrogen were inducted with the inlet air. Engine-performance data, indicator cards, and exhaust-gas samples were obtained for each change in engine-operating conditions.

  4. Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development and Performance Analysis

    Science.gov (United States)

    Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan; Kirchner, Robert; Engel, Carl D.

    2014-01-01

    The Space Launch System (SLS) base heating test is broken down into two test programs: (1) Pathfinder and (2) Main Test. The Pathfinder Test Program focuses on the design, development, hot-fire test and performance analyses of the 2% sub-scale SLS core-stage and booster element propulsion systems. The core-stage propulsion system is composed of four gaseous oxygen/hydrogen RS-25D model engines and the booster element is composed of two aluminum-based model solid rocket motors (SRMs). The first section of the paper discusses the motivation and test facility specifications for the test program. The second section briefly investigates the internal flow path of the design. The third section briefly shows the performance of the model RS-25D engines and SRMs for the conducted short duration hot-fire tests. Good agreement is observed based on design prediction analysis and test data. This program is a challenging research and development effort that has not been attempted in 40+ years for a NASA vehicle.

  5. Analysis of experimental hydrogen engine data and hydrogen vehicle performance and emissions simulation

    Energy Technology Data Exchange (ETDEWEB)

    Aceves, S.A. [Lawrence Livermore National Lab., CA (United States)

    1996-10-01

    This paper reports the engine and vehicle simulation and analysis done at Lawrence Livermore (LLNL) as a part of a joint optimized hydrogen engine development effort. Project participants are: Sandia National Laboratory; Los Alamos National Laboratory; and the University of Miami. Fuel cells are considered as the ideal power source for future vehicles, due to their high efficiency and low emissions. However, extensive use of fuel cells in light-duty vehicles is likely to be years away, due to their high manufacturing cost. Hydrogen-fueled, spark-ignited, homogeneous-charge engines offer a near-term alternative to fuel cells. Hydrogen in a spark-ignited engine can be burned at very low equivalence ratios. NO{sub x} emissions can be reduced to less than 10 ppm without catalyst. HC and CO emissions may result from oxidation of engine oil, but by proper design are negligible (a few ppm). Lean operation also results in increased indicated efficiency due to the thermodynamic properties of the gaseous mixture contained in the cylinder. The high effective octane number of hydrogen allows the use of a high compression ratio, further increasing engine efficiency. In this paper, a simplified engine model is used for predicting hydrogen engine efficiency and emissions. The model uses basic thermodynamic equations for the compression and expansion processes, along with an empirical correlation for heat transfer, to predict engine indicated efficiency. A friction correlation and a supercharger/turbocharger model are then used to calculate brake thermal efficiency. The model is validated with many experimental points obtained in a recent evaluation of a hydrogen research engine. The experimental data are used to adjust the empirical constants in the heat release rate and heat transfer correlation. The results indicate that hydrogen lean-burn spark-ignite engines can provide Equivalent Zero Emission Vehicle (EZEV) levels in either a series hybrid or a conventional automobile.

  6. 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.

  7. Optical Measurement Techniques for Rocket Engine Testing and Component Applications: Digital Image Correlation and Dynamic Photogrammetry

    Science.gov (United States)

    Gradl, Paul

    2016-01-01

    NASA Marshall Space Flight Center (MSFC) has been advancing dynamic optical measurement systems, primarily Digital Image Correlation, for extreme environment rocket engine test applications. The Digital Image Correlation (DIC) technology is used to track local and full field deformations, displacement vectors and local and global strain measurements. This technology has been evaluated at MSFC through lab testing to full scale hotfire engine testing of the J-2X Upper Stage engine at Stennis Space Center. It has been shown to provide reliable measurement data and has replaced many traditional measurement techniques for NASA applications. NASA and AMRDEC have recently signed agreements for NASA to train and transition the technology to applications for missile and helicopter testing. This presentation will provide an overview and progression of the technology, various testing applications at NASA MSFC, overview of Army-NASA test collaborations and application lessons learned about Digital Image Correlation.

  8. Hydrogen-Assisted IC Engine Combustion as a Route to Hydrogen Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Andre Boehman; Daniel Haworth

    2008-09-30

    The 'Freedom Car' Initiative announced by the Bush Administration has placed a significant emphasis on development of a hydrogen economy in the United States. While the hydrogen-fueled fuel-cell vehicle that is the focus of the 'Freedom Car' program would rely on electrochemical energy conversion, and despite the large amount of resources being devoted to its objectives, near-term implementation of hydrogen in the transportation sector is not likely to arise from fuel cell cars. Instead, fuel blending and ''hydrogen-assisted'' combustion are more realizable pathways for wide-scale hydrogen utilization within the next ten years. Thus, a large potential avenue for utilization of hydrogen in transportation applications is through blending with natural gas, since there is an existing market for natural-gas vehicles of various classes, and since hydrogen can provide a means of achieving even stricter emissions standards. Another potential avenue is through use of hydrogen to 'assist' diesel combustion to permit alternate combustion strategies that can achieve lower emissions and higher efficiency. This project focused on developing the underlying fundamental information to support technologies that will facilitate the introduction of coal-derived hydrogen into the market. Two paths were envisioned for hydrogen utilization in transportation applications. One is for hydrogen to be mixed with other fuels, specifically natural gas, to enhance performance in existing natural gas-fueled vehicles (e.g., transit buses) and provide a practical and marketable avenue to begin using hydrogen in the field. A second is to use hydrogen to enable alternative combustion modes in existing diesel engines, such as homogeneous charge compression ignition, to permit enhanced efficiency and reduced emissions. Thus, this project on hydrogen-assisted combustion encompassed two major objectives: (1) Optimization of hydrogen-natural gas mixture

  9. IMPROVEMENT OF ELECTROCHEMICAL PROCESSES IN HYDROGEN POWER ENGINEERING

    Directory of Open Access Journals (Sweden)

    Covaliova O.V.

    2011-04-01

    Full Text Available The possibility is studied of using the three-dimensional voluminous-porous electrodes made of the carbonic-fibrous materials and foamy metals, which surface is covered with Ni-Re alloy, for hydrogen electrochemical generation. Electrode surface modification makes it possible to obtain high reactive surface with low overvoltage of hydrogen evolution. The design is given of the developed compact electrochemical reactors for hydrogen power engineering. The method is described of oxygen-hydrogen mixture separation in the water electrolysis processes.

  10. Application of High Speed Digital Image Correlation in Rocket Engine Hot Fire Testing

    Science.gov (United States)

    Gradl, Paul R.; Schmidt, Tim

    2016-01-01

    Hot fire testing of rocket engine components and rocket engine systems is a critical aspect of the development process to understand performance, reliability and system interactions. Ground testing provides the opportunity for highly instrumented development testing to validate analytical model predictions and determine necessary design changes and process improvements. To properly obtain discrete measurements for model validation, instrumentation must survive in the highly dynamic and extreme temperature application of hot fire testing. Digital Image Correlation has been investigated and being evaluated as a technique to augment traditional instrumentation during component and engine testing providing further data for additional performance improvements and cost savings. The feasibility of digital image correlation techniques were demonstrated in subscale and full scale hotfire testing. This incorporated a pair of high speed cameras to measure three-dimensional, real-time displacements and strains installed and operated under the extreme environments present on the test stand. The development process, setup and calibrations, data collection, hotfire test data collection and post-test analysis and results are presented in this paper.

  11. To MARS and Beyond with Nuclear Power - Design Concept of Korea Advanced Nuclear Thermal Engine Rocket

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Seung Hyun; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2013-05-15

    The President Park of ROK has also expressed support for space program promotion, praising the success of NARO as evidence of a positive outlook. These events hint a strong signal that ROK's space program will be accelerated by the national eager desire. In this national eager desire for space program, the policymakers and the aerospace engineers need to pay attention to the advanced nuclear technology of ROK that is set to a major world nuclear energy country, even exporting the technology. The space nuclear application is a very much attractive option because its energy density is the most enormous among available energy sources in space. This paper presents the design concept of Korea Advanced Nuclear Thermal Engine Rocket (KANuTER) that is one of the advanced nuclear thermal rocket engine developing in Korea Advanced Institute of Science and Technology (KAIST) for space application. Solar system exploration relying on CRs suffers from long trip time and high cost. In this regard, nuclear propulsion is a very attractive option for that because of higher performance and already demonstrated technology. Although ROK was a late entrant into elite global space club, its prospect as a space racer is very bright because of the national eager desire and its advanced technology. Especially it is greatly meaningful that ROK has potential capability to launch its nuclear technology into space as a global nuclear energy leader and a soaring space adventurer. In this regard, KANuTER will be a kind of bridgehead for Korean space nuclear application.

  12. Liquid propellant rocket engine combustion simulation with a time-accurate CFD method

    Science.gov (United States)

    Chen, Y. S.; Shang, H. M.; Liaw, Paul; Hutt, J.

    1993-01-01

    Time-accurate computational fluid dynamics (CFD) algorithms are among the basic requirements as an engineering or research tool for realistic simulations of transient combustion phenomena, such as combustion instability, transient start-up, etc., inside the rocket engine combustion chamber. A time-accurate pressure based method is employed in the FDNS code for combustion model development. This is in connection with other program development activities such as spray combustion model development and efficient finite-rate chemistry solution method implementation. In the present study, a second-order time-accurate time-marching scheme is employed. For better spatial resolutions near discontinuities (e.g., shocks, contact discontinuities), a 3rd-order accurate TVD scheme for modeling the convection terms is implemented in the FDNS code. Necessary modification to the predictor/multi-corrector solution algorithm in order to maintain time-accurate wave propagation is also investigated. Benchmark 1-D and multidimensional test cases, which include the classical shock tube wave propagation problems, resonant pipe test case, unsteady flow development of a blast tube test case, and H2/O2 rocket engine chamber combustion start-up transient simulation, etc., are investigated to validate and demonstrate the accuracy and robustness of the present numerical scheme and solution algorithm.

  13. Modular simulation software development for liquid propellant rocket engines based on MATLAB Simulink

    Directory of Open Access Journals (Sweden)

    Naderi Mahyar

    2017-01-01

    Full Text Available Focusing on Liquid Propellant Rocket Engine (LPRE major components, a steady state modular simulation software has been established in MATLAB Simulink. For integrated system analysis, a new algorithm dependant on engine inlet mass flow rate and pressure is considered. Using the suggested algorithm, it is possible to evaluate engine component operation, similar to the known initial parameters during hot fire test of the engine on stand. As a case study, the reusable Space Shuttle Main Engine (SSME has been selected and the simulation has been performed to predict engine’s throttled operation at 109 percent of the nominal thrust value. For this purpose the engine actual flow diagram has been converted to 34 numerical modules and the engine has been modelled by solving a total of 101 steady state mathematic equations. The mean error of the simulation results is found to be less than 5% compared with the published SSME data. Using the presented idea and developed modules, it is possible to build up the numerical model and simulate other LPREs.

  14. Ammonia/Hydrogen Mixtures in an SI-Engine

    DEFF Research Database (Denmark)

    Mørch, Christian Sandersen; Bjerre, Andreas; Gøttrup, Morten Piil

    2011-01-01

    In recent years there has been increasing focus on using metal ammine complexes for ammonia storage. In this paper a fuel system for ammonia fuelled internal combustion engines using metal ammine complexes as ammonia storage is analyzed. The use of ammonia/hydrogen mixtures as an SI-engine fuel...... is investigated in the same context. Ammonia and hydrogen were introduced into the intake manifold of a CFR-engine. Series of experiments with varying excess air ratio and different ammonia to hydrogen ratios was conducted. This showed that a fuel mixture with 10 vol.% hydrogen performs best with respect...... to efficiency and power. A comparison with gasoline was made, which showed efficiencies and power increased due to the possibility of a higher compression ratio. The system analysis showed that it is possible to cover a major part of the necessary heat using the exhaust heat. It is proposed to reduce the high...

  15. Energizing Engineering Students with Hydrogen Fuel Cell Project

    Science.gov (United States)

    Cannell, Nori; Zavaleta, Dan

    2010-01-01

    At Desert Vista High School, near Phoenix, Arizona, Perkins Innovation Grant funding is being used to fund a program that is helping to prepare students for careers in engineering by giving them hands-on experience in areas like hydrogen generation and fuel cell utilization. As one enters Dan Zavaleta's automotive and engineering classroom and lab…

  16. HYDROGEN USE IN INTERNAL COMBUSTION ENGINE:

    OpenAIRE

    Ciniviz, Murat

    2012-01-01

    Fast depletion of fossil fuels is urgently demanding a carry out work for research to find out the viable alternative fuels for meeting sustainable energy demand with minimum environmental impact. In the future, our energy systems will need to be renewable and sustainable, efficient and cost-effective, convenient and safe. Hydrogen is expected to be one of the most important fuels in the near future to meet the stringent emission norms. The use of the hydrogen as fuel in the internal combusti...

  17. Operation of a cryogenic rocket engine an outline with down-to-earth and up-to-space remarks

    CERN Document Server

    Kitsche, Wolfgang

    2010-01-01

    This book presents the operational aspects of the rocket engine on a test facility. It will be useful to engineers and scientists who are in touch with the test facility. To aerospace students it shall provide an insight of the job on the test facility. And to interest readers it shall provide an impression of this thrilling area of aerospace.

  18. Influence of atomization quality modulation on flame dynamics in a hypergolic rocket engine

    Directory of Open Access Journals (Sweden)

    Moritz Schulze

    2016-09-01

    Full Text Available For the numerical evaluation of the thermoacoustic stability of rocket engines often hybrid methods are applied, which separate the computation of wave propagation in the combustor from the analysis of the flame response to acoustic perturbations. Closure requires a thermoacoustic feedback model which provides the heat release fluctuation in the source term of the employed wave transport equations. The influence of the acoustic fluctuations in the combustion chamber on the heat release fluctuations from the modulation of the atomization of the propellants in a hypergolic upper stage rocket engine is studied. Numerical modeling of a single injector provides the time mean reacting flow field. A network of transfer functions representing all aspects relevant for the feedback model is presented. Analytical models for the injector admittances and for the atomization transfer functions are provided. The dynamics of evaporation and combustion are studied numerically and the numerical results are analyzed. An analytical approximation of the computed flame transfer function is combined with the analytical models for the injector and the atomization quality to derive the feedback model for the wave propagation code. The evaluation of this model on the basis of the Rayleigh index reveals the thermoacoustic driving potential originating from the fluctuating spray quality.

  19. Development of preliminary design program for combustor of regenerative cooled liquid rocket engine

    Science.gov (United States)

    Cho, Won Kook; Seol, Woo Seok; Son, Min; Seo, Min Kyo; Koo, Jaye

    2011-10-01

    An integrated program was established to design a combustor for a liquid rocket engine and to analyze regenerative cooling results on a preliminary design level. Properties of burnt gas from a kerosene-LOx mixture in the combustor and rocket performance were calculated from CEA which is the code for the calculation of chemical equilibrium. The heat transfer of regenerative cooling was analyzed by using SUPERTRAPP code for coolant properties and by one-dimensional correlations of the heat transfer coefficient from the combustor liner to the coolant. Profiles of the combustors of F-1 and RS-27A engines were designed from similar input data and the present results were compared to actual data for validation. Finally, the combustors of 30 tonf class, 75 tonf class and 150 tonf class were designed from the required thrust, combustion chamber, exit pressure and mixture ratio of propellants. The wall temperature, heat flux and pressure drop were calculated for heat transfer analysis of regenerative cooling using the profiles.

  20. Analysis of experimental hydrogen engine data and hydrogen vehicle performance and emissions simulation

    Energy Technology Data Exchange (ETDEWEB)

    Aceves, S.M.

    1996-09-01

    This paper reports the engine and vehicle simulation and analysis done at Lawrence Livermore (LLNL) as a part of a joint optimized hydrogen engine development effort. Project participants are: Sandia National Laboratory, California (SNLC), responsible for experimental evaluation; Los Alamos National Laboratory (LANL), responsible for detailed fluid mechanics engine evaluations, and the University of Miami, responsible for engine friction reduction. Fuel cells are considered as the ideal power source for future vehicles, due to their high efficiency and low emissions. However, extensive use of fuel cells in light-duty vehicles is likely to be years away, due to their high manufacturing cost. Hydrogen-fueled, spark-ignited, homogeneous-charge engines offer a near-term alternative to fuel cells. Hydrogen in a spark-ignited engine can be burned at very low equivalence ratios, so that NO{sub x} emissions can be reduced to less than 10 ppm without catalyst. HC and CO emissions may result from oxidation of engine oil, but by proper design are negligible (a few ppm). Lean operation also results in increased indicated efficiency due to the thermodynamic properties of the gaseous mixture contained in the cylinder. The high effective octane number of hydrogen allows the use of a high compression ratio, further increasing engine efficiency.

  1. Thermo-mechanical concepts applied to modeling liquid propellant rocket engine stability

    Science.gov (United States)

    Kassoy, David R.; Norris, Adam

    2016-11-01

    The response of a gas to transient, spatially distributed energy addition can be quantified mathematically using thermo-mechanical concepts available in the literature. The modeling demonstrates that the ratio of the energy addition time scale to the acoustic time scale of the affected volume, and the quantity of energy added to that volume during the former determine the whether the responses to heating can be described as occurring at nearly constant volume, fully compressible or nearly constant pressure. Each of these categories is characterized by significantly different mechanical responses. Application to idealized configurations of liquid propellant rocket engines provides an opportunity to identify physical conditions compatible with gasdynamic disturbances that are sources of engine instability. Air Force Office of Scientific Research.

  2. Towards Rocket Engine Components with Increased Strength and Robust Operating Characteristics

    Science.gov (United States)

    Marcu, Bogdan; Hadid, Ali; Lin, Pei; Balcazar, Daniel; Rai, Man Mohan; Dorney, Daniel J.

    2005-01-01

    High-energy rotating machines, powering liquid propellant rocket engines, are subject to various sources of high and low cycle fatigue generated by unsteady flow phenomena. Given the tremendous need for reliability in a sustainable space exploration program, a fundamental change in the design methodology for engine components is required for both launch and space based systems. A design optimization system based on neural-networks has been applied and demonstrated in the redesign of the Space Shuttle Main Engine (SSME) Low Pressure Oxidizer Turbo Pump (LPOTP) turbine nozzle. One objective of the redesign effort was to increase airfoil thickness and thus increase its strength while at the same time detuning the vane natural frequency modes from the vortex shedding frequency. The second objective was to reduce the vortex shedding amplitude. The third objective was to maintain this low shedding amplitude even in the presence of large manufacturing tolerances. All of these objectives were achieved without generating any detrimental effects on the downstream flow through the turbine, and without introducing any penalty in performance. The airfoil redesign and preliminary assessment was performed in the Exploration Technology Directorate at NASA ARC. Boeing/Rocketdyne and NASA MSFC independently performed final CFD assessments of the design. Four different CFD codes were used in this process. They include WIL DCA T/CORSAIR (NASA), FLUENT (commercial), TIDAL (Boeing Rocketdyne) and, a new family (AardvarWPhantom) of CFD analysis codes developed at NASA MSFC employing LOX fluid properties and a Generalized Equation Set formulation. Extensive aerodynamic performance analysis and stress analysis carried out at Boeing Rocketdyne and NASA MSFC indicate that the redesign objectives have been fully met. The paper presents the results of the assessment analysis and discusses the future potential of robust optimal design for rocket engine components.

  3. Experimental Altitude Performance of JP-4 Fuel and Liquid-Oxygen Rocket Engine with an Area Ratio of 48

    Science.gov (United States)

    Fortini, Anthony; Hendrix, Charles D.; Huff, Vearl N.

    1959-01-01

    The performance for four altitudes (sea-level, 51,000, 65,000, and 70,000 ft) of a rocket engine having a nozzle area ratio of 48.39 and using JP-4 fuel and liquid oxygen as a propellant was evaluated experimentally by use of a 1000-pound-thrust engine operating at a chamber pressure of 600 pounds per square inch absolute. The altitude environment was obtained by a rocket-ejector system which utilized the rocket exhaust gases as the pumping fluid of the ejector. Also, an engine having a nozzle area ratio of 5.49 designed for sea level was tested at sea-level conditions. The following table lists values from faired experimental curves at an oxidant-fuel ratio of 2.3 for various approximate altitudes.

  4. Digital Image Correlation Techniques Applied to Large Scale Rocket Engine Testing

    Science.gov (United States)

    Gradl, Paul R.

    2016-01-01

    Rocket engine hot-fire ground testing is necessary to understand component performance, reliability and engine system interactions during development. The J-2X upper stage engine completed a series of developmental hot-fire tests that derived performance of the engine and components, validated analytical models and provided the necessary data to identify where design changes, process improvements and technology development were needed. The J-2X development engines were heavily instrumented to provide the data necessary to support these activities which enabled the team to investigate any anomalies experienced during the test program. This paper describes the development of an optical digital image correlation technique to augment the data provided by traditional strain gauges which are prone to debonding at elevated temperatures and limited to localized measurements. The feasibility of this optical measurement system was demonstrated during full scale hot-fire testing of J-2X, during which a digital image correlation system, incorporating a pair of high speed cameras to measure three-dimensional, real-time displacements and strains was installed and operated under the extreme environments present on the test stand. The camera and facility setup, pre-test calibrations, data collection, hot-fire test data collection and post-test analysis and results are presented in this paper.

  5. A Programmatic and Engineering Approach to the Development of a Nuclear Thermal Rocket for Space Exploration

    Science.gov (United States)

    Bordelon, Wayne J., Jr.; Ballard, Rick O.; Gerrish, Harold P., Jr.

    2006-01-01

    With the announcement of the Vision for Space Exploration on January 14, 2004, there has been a renewed interest in nuclear thermal propulsion. Nuclear thermal propulsion is a leading candidate for in-space propulsion for human Mars missions; however, the cost to develop a nuclear thermal rocket engine system is uncertain. Key to determining the engine development cost will be the engine requirements, the technology used in the development and the development approach. The engine requirements and technology selection have not been defined and are awaiting definition of the Mars architecture and vehicle definitions. The paper discusses an engine development approach in light of top-level strategic questions and considerations for nuclear thermal propulsion and provides a suggested approach based on work conducted at the NASA Marshall Space Flight Center to support planning and requirements for the Prometheus Power and Propulsion Office. This work is intended to help support the development of a comprehensive strategy for nuclear thermal propulsion, to help reduce the uncertainty in the development cost estimate, and to help assess the potential value of and need for nuclear thermal propulsion for a human Mars mission.

  6. Experimental results with hydrogen fueled internal combustion engines

    Science.gov (United States)

    De Boer, P. C. T.; Mclean, W. J.; Homan, H. S.

    1975-01-01

    The paper focuses on the most important experimental findings for hydrogen-fueled internal combustion engines, with particular reference to the application of these findings to the assessment of the potential of hydrogen engines. Emphasis is on the various tradeoffs that can be made, such as between maximum efficiency, maximum power, and minimum NO emissions. The various possibilities for induction and ignition are described. Some projections are made about areas in which hydrogen engines may find their initial application and about optimum ways to design such engines. It is shown that hydrogen-fueled reciprocal internal combustion engines offer important advantages with respect to thermal efficiency and exhaust emissions. Problems arising from preignition can suitably be avoided by restricting the fuel-air equivalence ratio to values below about 0.5. The direct cylinder injection appears to be a very attractive way to operate the engine, because it combines a wide range of possible power outputs with a high thermal efficiency and very low NO emissions at part loads.

  7. Role of hydrogen on engineering education. ICHET example

    Energy Technology Data Exchange (ETDEWEB)

    Yazici, M. Suha [International Centre for Hydrogen Energy Technologies, Istanbul (Turkey)

    2010-07-01

    International Center for Hydrogen Energy Technologies (ICHET) has been successfully supporting engineering students with practical experience on ''hydrogen and fuel cell systems built upon their theoretical engineering learning through classroom. A series of activities designed to increase the knowledge and awareness of engineering students and advancedresearchers has been implemented. These activities can be classified under meetings, system integration and training activities. Meeting activities include short courses, technology specific workshops and conferences, sponsorships and summer schools. System integration for prototype demonstrations forms the basis for hand-on practical learning through university-industry collaboration, demonstration activities and application specific supports. Training activities involve internships, part-time employment and laboratory educations. All these activities facilitate knowledge transfer, exchange of information at regional, national and international levels and involve academics, researchers, experts and service providers to further develop their knowledge and interest on hydrogen energy technologies. (orig.)

  8. Focused Rocket-Ejector RBCC Experiments

    Science.gov (United States)

    Santoro, Robert J.; Pal, Sibtosh

    2003-01-01

    This document reports the results of additional efforts for the Rocket Based Combined Cycle (RBCC) rocket-ejector mode research work carried out at the Perm State Propulsion Engineering Research Center in support of NASA s technology development efforts for enabling 3rd generation Reusable Launch Vehicles (RLV). The two tasks conducted under this program build on earlier NASA MSFC funded research program on rocket ejector investigations. The first task continued a systematic investigation of the improvements provided by a gaseous hydrogen (GHz)/oxygen (GO2) twin thruster RBCC rocket ejector system over a single rocket system. In a similar vein, the second task continued investigations into the performance of a hydrocarbon (liquid JP-7)/gaseous oxygen single thruster rocket-ejector system. To gain a systematic understanding of the rocket-ejector s internal fluid mechanic/combustion phenomena, experiments were conducted with both direct-connect and sea-level static diffusion and afterburning (DAB) configurations for a range of rocket operating conditions. For all experimental conditions, overall system performance was obtained through global measurements of wall static pressure profiles, heat flux profiles and engine thrust. For the GH2/GO2 propellant rocket ejector experiments, high frequency measurements of the pressure field within the system were also made to understand the unsteady behavior of the flowfield.

  9. High Thermal Conductivity NARloy-Z-Diamond Composite Combustion Chamber Liner For Advanced Rocket Engines

    Science.gov (United States)

    Bhat, Biliyar N.; Ellis, David; Singh, Jogender

    2014-01-01

    Advanced high thermal conductivity materials research conducted at NASA Marshall Space Flight Center (MSFC) with state of the art combustion chamber liner material NARloy-Z showed that its thermal conductivity can be increased significantly by adding diamond particles and sintering it at high temperatures. For instance, NARloy-Z containing 40 vol. percent diamond particles, sintered at 975C to full density by using the Field assisted Sintering Technology (FAST) showed 69 percent higher thermal conductivity than baseline NARloy-Z. Furthermore, NARloy-Z-40vol. percent D is 30 percent lighter than NARloy-Z and hence the density normalized thermal conductivity is 140 percent better. These attributes will improve the performance and life of the advanced rocket engines significantly. By one estimate, increased thermal conductivity will directly translate into increased turbopump power up to 2X and increased chamber pressure for improved thrust and ISP, resulting in an expected 20 percent improvement in engine performance. Follow on research is now being conducted to demonstrate the benefits of this high thermal conductivity NARloy-Z-D composite for combustion chamber liner applications in advanced rocket engines. The work consists of a) Optimizing the chemistry and heat treatment for NARloy-Z-D composite, b) Developing design properties (thermal and mechanical) for the optimized NARloy-Z-D, c) Fabrication of net shape subscale combustion chamber liner, and d) Hot fire testing of the liner for performance. FAST is used for consolidating and sintering NARlo-Z-D. The subscale cylindrical liner with built in channels for coolant flow is also fabricated near net shape using the FAST process. The liner will be assembled into a test rig and hot fire tested in the MSFC test facility to determine performance. This paper describes the development of this novel high thermal conductivity NARloy-Z-D composite material, and the advanced net shape technology to fabricate the combustion

  10. Elimination of abnormal combustion in a hydrogen-fueled engine

    Energy Technology Data Exchange (ETDEWEB)

    Swain, M.R.; Swain, M.N. [Analytical Technologies, Inc., Miami, FL (United States)

    1995-11-01

    This report covers the design, construction, and testing of a dedicated hydrogen-fueled engine. Both part-load and full-load data were taken under laboratory conditions. The engine design included a billet aluminum single combustion chamber cylinder-head with one intake valve, two sodium coiled exhaust valves, and two spark plugs. The cylinder-head design also included drilled cooling passages. The fuel-delivery system employed two modified Siemens electrically actuated fuel injectors, The exhaust system included two separate headers, one for each exhaust port. The piston/ring combination was designed specifically for hydrogen operation.

  11. An experimental investigation of reacting and nonreacting coaxial jet mixing in a laboratory rocket engine

    Science.gov (United States)

    Schumaker, Stephen Alexander

    Coaxial jets are commonly used as injectors in propulsion and combustion devices due to both the simplicity of their geometry and the rapid mixing they provide. In liquid rocket engines it is common to use coaxial jets in the context of airblast atomization. However, interest exists in developing rocket engines using a full flow staged combustion cycle. In such a configuration both propellants are injected in the gaseous phase. In addition, gaseous coaxial jets have been identified as an ideal test case for the validation of the next generation of injector modeling tools. For these reasons an understanding of the fundamental phenomena which govern mixing in gaseous coaxial jets and the effect of combustion on these phenomena in coaxial jet diffusion flames is needed. A study was performed to better understand the scaling of the stoichiometric mixing length in reacting and nonreacting coaxial jets with velocity ratios greater than one and density ratios less than one. A facility was developed that incorporates a single shear coaxial injector in a laboratory rocket engine capable of ten atmospheres. Optical access allows the use of flame luminosity and laser diagnostic techniques such as Planar Laser Induced Fluorescence (PLIF). Stoichiometric mixing lengths (LS), which are defined as the distance along the centerline where the stoichiometric condition occurs, were measured using PLIF. Acetone was seeded into the center jet to provide direct PLIF measurement of the average and instantaneous mixture fraction fields for a range of momentum flux ratios for the nonreacting cases. For the coaxial jet diffusion flames, LS was measured from OH radical contours. For nonreacting cases the use of a nondimensional momentum flux ratio was found to collapse the mixing length data. The flame lengths of coaxial jet diffusion flames were also found to scale with the momentum flux ratio but different scaling constants are required which depended on the chemistry of the reaction. The

  12. Characteristics of Knock in Hydrogen-Oxygen-Argon SI Engine

    Energy Technology Data Exchange (ETDEWEB)

    Killingsworth, N; Rapp, V; Flowers, D; Aceves, S; Chen, J; Dibble, R

    2010-02-23

    A promising approach for improving the efficiency of internal combustion engines is to employ a working fluid with a high specific heat ratio such as the noble gas argon. Moreover, all harmful emissions are eliminated when the intake charge is composed of oxygen, nonreactive argon, and hydrogen fuel. Previous research demonstrated indicated thermal efficiencies greater than 45% at 5.5 compression ratio in engines operating with hydrogen, oxygen, and argon. However, knock limits spark advance and increasing the efficiency further. Conditions under which knock occurs in such engines differs from typical gasoline fueled engines. In-cylinder temperatures using hydrogen-oxygen-argon are higher due to the high specific heat ratio and pressures are lower because of the low compression ratio. Better understanding of knock under these conditions can lead to operating strategies that inhibit knock and allow operation closer to the knock limit. In this work we compare knock with a hydrogen, oxygen, and argon mixture to that of air-gasoline mixtures in a variable compression ratio cooperative fuels research (CFR) engine. The focus is on stability of knocking phenomena, as well as, amplitude and frequency of the resulting pressure waves.

  13. Extensions to the time lag models for practical application to rocket engine stability design

    Science.gov (United States)

    Casiano, Matthew J.

    The combustion instability problem in liquid-propellant rocket engines (LREs) has remained a tremendous challenge since their discovery in the 1930s. Improvements are usually made in solving the combustion instability problem primarily using computational fluid dynamics (CFD) and also by testing demonstrator engines. Another approach is to use analytical models. Analytical models can be used such that design, redesign, or improvement of an engine system is feasible in a relatively short period of time. Improvements to the analytical models can greatly aid in design efforts. A thorough literature review is first conducted on liquid-propellant rocket engine (LRE) throttling. Throttling is usually studied in terms of vehicle descent or ballistic missile control however there are many other cases where throttling is important. It was found that combustion instabilities are one of a few major issues that occur during deep throttling (other major issues are heat transfer concerns, performance loss, and pump dynamics). In the past and again recently, gas injected into liquid propellants has shown to be a viable solution to throttle engines and to eliminate some forms of combustion instability. This review uncovered a clever solution that was used to eliminate a chug instability in the Common Extensible Cryogenic Engine (CECE), a modified RL10 engine. A separate review was also conducted on classic time lag combustion instability models. Several new stability models are developed by incorporating important features to the classic and contemporary models, which are commonly used in the aerospace rocket industry. The first two models are extensions of the original Crocco and Cheng concentrated combustion model with feed system contributions. A third new model is an extension to the Wenzel and Szuch double-time lag model also with feed system contributions. The first new model incorporates the appropriate injector acoustic boundary condition which is neglected in contemporary

  14. Progress toward an optimized hydrogen series hybrid engine

    Science.gov (United States)

    Smith, J. Ray; Aceves, Salvador M.; Johnson, Norman L.; Amsden, Anthony A.

    1995-06-01

    The design considerations and computational fluid dynamics (CFD) modeling of a high efficiency, low emissions, hydrogen-fueled engine for use as the prime mover of a series hybrid automobile is described. The series hybrid automobile uses the engine to generate electrical energy via a lightweight generator, the electrical energy is stored in a power peaking device (like a flywheel or ultracapacitor) and used as required to meet the tractive drive requirements (plus accessory loads) through an electrical motor. The engine/generator is stopped whenever the energy storage device is fully charged. Engine power output required was determined with a vehicle simulation code to be 15 to 20 kW steady state with peak output of 40 to 45 kW for hill climb. Combustion chamber and engine geometry were determined from a critical review of the hydrogen engine experiments in the literature combined with a simplified global engine model. Two different engine models are employed to guide engine design. The models are a simplified global engine performance model that relies strongly on correlations with literature data for heat transfer and friction losses, and a state-of-the-art CFD combustion model, KIVA-3, to elucidate fluid mechanics and combustion details through full three-dimensional modeling. Both intake and exhaust processes as well as hydrogen combustion chemistry and thermal NO(sub x) production are simulated. Ultimately, a comparison between the simulation and experimental results will lead to improved modeling and will give guidance to changes required in the next generation engine to achieve the goal of 45% brake thermal efficiency.

  15. Experiment/Analytical Characterization of the RBCC Rocket-Ejector Mode

    Science.gov (United States)

    Ruf, J. H.; Lehman, M.; Pal, S.; Santoro, R. J.; West, J.; Turner, James E. (Technical Monitor)

    2000-01-01

    Experimental and complementary CFD results from the study of the rocket-ejector mode of a Rocket Based Combined Cycle (RBCC) engine are presented and discussed. The experiments involved systematic flowfield measurements in a two-dimensional, variable geometry rocket-ejector system. The rocket-ejector system utilizes a single two-dimensional, gaseous oxygen/gaseous hydrogen rocket as the ejector. To gain a thorough understanding of the rocket-ejector's internal fluid mechanic/combustion phenomena, experiments were conducted with both direct-connect and sea-level static configurations for a range of rocket operating conditions. Overall system performance was obtained through global measurements of wall static pressure profiles, heat flux profiles and engine thrust, whereas detailed mixing and combustion information was obtained through Raman spectroscopy measurements of major species (oxygen, hydrogen, nitrogen and water vapor). The experimental results for both the direct-connect and sea-level static configurations are compared with CFD predictions of the flowfield.

  16. Focused Experimental and Analytical Studies of the RBCC Rocket-Ejector

    Science.gov (United States)

    Lehman, M.; Pal, S.; Schwes, D.; Chen, J. D.; Santoro, R. J.

    1999-01-01

    The rocket-ejector mode of a Rocket Based Combined Cycle Engine (RBCC) was studied through a joint experimental/analytical approach. A two-dimensional variable geometry rocket-ejector system with enhanced optical access was designed and fabricated for experimentation. The rocket-ejector system utilizes a single two-dimensional gaseous oxygen/gaseous hydrogen rocket as the ejector. To gain a systematic understanding of the rocket ejector's internal fluid mechanic/combustion phenomena, experiments were conducted with both direct-connect and sea-level static configurations for a range of rocket operating conditions Overall system performance was obtained through Global measurements of wall static pressure profiles, heat flux profiles and engine thrust, whereas detailed mixing and combustion information was obtained through Raman spectroscopy measurements of major species (gaseous oxygen, hydrogen. nitrogen and water vapor). These experimental efforts were complemented by Computational Fluid Dynamic (CFD) flowfield analyses.

  17. A Hydrogen Containment Process for Nuclear Thermal Engine Ground testing

    Science.gov (United States)

    Wang, Ten-See; Stewart, Eric; Canabal, Francisco

    2016-01-01

    The objective of this study is to propose a new total hydrogen containment process to enable the testing required for NTP engine development. This H2 removal process comprises of two unit operations: an oxygen-rich burner and a shell-and-tube type of heat exchanger. This new process is demonstrated by simulation of the steady state operation of the engine firing at nominal conditions.

  18. Computational Analysis of an LOx Supply Line System of an Liquid Rocket Engine

    Directory of Open Access Journals (Sweden)

    Insang Moon

    2009-12-01

    Full Text Available A computational fluid analysis was performed on an LOx line system of a liquid rocket engine. The model was created with 3D CAD and imbedded to the 3D CFD program. Before the full scale analysis on the system was carried out, each components with simplified models was analyzed to save time and cost. As a result, the inlet pressure of the gas generator should be compensated with a certain device unless the inlet pressure of the line system is sufficiently high. The flow pattern of the exit of the system was dependant upon the location of the orifice as well as the size. As a whole the line system analyzed met the requirements, and will be tested and confirmed after being manufactured.

  19. An experimental investigation of liquid methane convection and boiling in rocket engine cooling channels

    Science.gov (United States)

    Trujillo, Abraham Gerardo

    In the past decades, interest in developing hydrocarbon-fueled rocket engines for deep spaceflight missions has continued to grow. In particular, liquid methane (LCH4) has been of interest due to the weight efficiency, storage, and handling advantages it offers over several currently used propellants. Deep space exploration requires reusable, long life rocket engines. Due to the high temperatures reached during combustion, the life of an engine is significantly impacted by the cooling system's efficiency. Regenerative (regen) cooling is presented as a viable alternative to common cooling methods such as film and dump cooling since it provides improved engine efficiency. Due to limited availability of experimental sub-critical liquid methane cooling data for regen engine design, there has been an interest in studying the heat transfer characteristics of the propellant. For this reason, recent experimental studies at the Center for Space Exploration Technology Research (cSETR) at the University of Texas at El Paso (UTEP) have focused on investigating the heat transfer characteristics of sub-critical CH4 flowing through sub-scale cooling channels. To conduct the experiments, the csETR developed a High Heat Flux Test Facility (HHFTF) where all the channels are heated using a conduction-based thermal concentrator. In this study, two smooth channels with cross sectional geometries of 1.8 mm x 4.1 mm and 3.2 mm x 3.2 mm were tested. In addition, three roughened channels all with a 3.2 mm x 3.2 mm square cross section were also tested. For the rectangular smooth channel, Reynolds numbers ranged between 68,000 and 131,000, while the Nusselt numbers were between 40 and 325. For the rough channels, Reynolds numbers ranged from 82,000 to 131,000, and Nusselt numbers were between 65 and 810. Sub-cooled film-boiling phenomena were confirmed for all the channels presented in this work. Film-boiling onset at Critical Heat Flux (CHF) was correlated to a Boiling Number (Bo) of

  20. Evaluation of Open Cell Foam Heat Transfer Enhancement for Liquid Rocket Engine

    Science.gov (United States)

    Chung, J. N.; Tully, Landon; Kim, Jung Hwan; Jones, Gregg W.; Watkins, William

    2006-01-01

    As NASA pursues the exploration mission, advanced propulsion for the next generation of spacecraft will be needed. These new propulsion systems will require higher performance and increased durability, despite current limitations on materials. A break-through technology is needed in the thrust chamber. In this paper the idea of using a porous metallic foam is examined for its potential cooling enhancement capabilities. The goal is to increase the chamber wall cooling without creating an additional pressure drop penalty. A feasibility study based on experiments at laboratory-scale conditions was performed and analysis at rocket conditions is underway. In the experiment, heat transfer and pressure drop data were collected using air as the coolant in a copper or nickel foam filled annular channel. The foam-channel performance was evaluated based on comparison with conventional microchannel cooling passages under equal pressure drop conditions. The heat transfer enhancement of the foam channel over the microchannel ranges from 130% to 172%. The enhancement is relatively independent of the pressure drop and increases with decreasing pore size. A direct numerical simulation model of the foam heat exchange has been built. The model is based on the actual metal foam microstructure of thin ligaments (0.2- 0.3 mm in diameter) that form a network of interconnected open-cells. The cell dimension is around 2 mm. The numerical model was built using the FLUENT CFD code. Comparison of the pressure drop results predicted by the current model with those experimental data of Leong and Jin [8] shows favorable comparisons. Pressure drop predictions have been made using hydrogen as a coolant at typical rocket conditions. Conjugate heat transfer analysis using the foam filled channel is planned for the future.

  1. Fatigue life prediction of liquid rocket engine combustor with subscale test verification

    Science.gov (United States)

    Sung, In-Kyung

    Reusable rocket systems such as the Space Shuttle introduced a new era in propulsion system design for economic feasibility. Practical reusable systems require an order of magnitude increase in life. To achieve this improved methods are needed to assess failure mechanisms and to predict life cycles of rocket combustor. A general goal of the research was to demonstrate the use of subscale rocket combustor prototype in a cost-effective test program. Life limiting factors and metal behaviors under repeated loads were surveyed and reviewed. The life prediction theories are presented, with an emphasis on studies that used subscale test hardware for model validation. From this review, low cycle fatigue (LCF) and creep-fatigue interaction (ratcheting) were identified as the main life limiting factors of the combustor. Several life prediction methods such as conventional and advanced viscoplastic models were used to predict life cycle due to low cycle thermal stress, transient effects, and creep rupture damage. Creep-fatigue interaction and cyclic hardening were also investigated. A prediction method based on 2D beam theory was modified using 3D plate deformation theory to provide an extended prediction method. For experimental validation two small scale annular plug nozzle thrusters were designed, built and tested. The test article was composed of a water-cooled liner, plug annular nozzle and 200 psia precombustor that used decomposed hydrogen peroxide as the oxidizer and JP-8 as the fuel. The first combustor was tested cyclically at the Advanced Propellants and Combustion Laboratory at Purdue University. Testing was stopped after 140 cycles due to an unpredicted failure mechanism due to an increasing hot spot in the location where failure was predicted. A second combustor was designed to avoid the previous failure, however, it was over pressurized and deformed beyond repair during cold-flow test. The test results are discussed and compared to the analytical and numerical

  2. Fuzzy/Neural Software Estimates Costs of Rocket-Engine Tests

    Science.gov (United States)

    Douglas, Freddie; Bourgeois, Edit Kaminsky

    2005-01-01

    The Highly Accurate Cost Estimating Model (HACEM) is a software system for estimating the costs of testing rocket engines and components at Stennis Space Center. HACEM is built on a foundation of adaptive-network-based fuzzy inference systems (ANFIS) a hybrid software concept that combines the adaptive capabilities of neural networks with the ease of development and additional benefits of fuzzy-logic-based systems. In ANFIS, fuzzy inference systems are trained by use of neural networks. HACEM includes selectable subsystems that utilize various numbers and types of inputs, various numbers of fuzzy membership functions, and various input-preprocessing techniques. The inputs to HACEM are parameters of specific tests or series of tests. These parameters include test type (component or engine test), number and duration of tests, and thrust level(s) (in the case of engine tests). The ANFIS in HACEM are trained by use of sets of these parameters, along with costs of past tests. Thereafter, the user feeds HACEM a simple input text file that contains the parameters of a planned test or series of tests, the user selects the desired HACEM subsystem, and the subsystem processes the parameters into an estimate of cost(s).

  3. Experimental testing of a liquid bipropellant rocket engine using nitrous oxide and ethanol diluted with water

    Science.gov (United States)

    Phillip, Jeff; Morales, Rudy; Youngblood, Stewart; Saul, W. Venner; Grubelich, Mark; Hargather, Michael

    2016-11-01

    A research scale liquid bipropellant rocket engine testing facility was constructed at New Mexico Tech to perform research with various propellants. The facility uses a modular engine design that allows for variation of nozzle geometry and injector configurations. Initial testing focused on pure nitrous oxide and ethanol propellants, operating in the range of 5.5-6.9 MPa (800-1000 psi) chamber pressure with approximately 667 N (150 lbf) thrust. The system is instrumented with sensors for temperature, pressure, and thrust. Experimentally found values for specific impulse are in the range of 250-260 s which match computational predictions. Exhaust flow visualization is performed using high speed schlieren imaging. The engine startup and steady state exhaust flow features are studied through these videos. Computational and experimental data are presented for a study of dilution of the ethanol-nitrous oxide propellants with water. The study has shown a significant drop in chamber temperature compared to a small drop in specific impulse with increasing water dilution.

  4. Self-oscillations of an unstable fuel combustion in the combustion chamber of a liquid-propellant rocket engine

    Science.gov (United States)

    Gotsulenko, V. V.; Gotsulenko, V. N.

    2013-01-01

    The form of the self-oscillations of a vibrating combustion of a fuel in the combustion chamber of a liquidpropellant rocket engine, caused by the fuel-combustion lag and the heat release, was determined. The character of change in these self-oscillations with increase in the time of the fuel-combustion lag was investigated.

  5. Comparison of the rocket engines efficiency in the case of low thrust orbit-to-orbit transfers

    Science.gov (United States)

    Kiforenko, Boris M.; Pasechnik, Zoya V.; Vasil'ev, Igor Yu.

    2007-05-01

    The main task of this paper is to compare two types of low thrust rocket engines: constant thrust vs. variable-thrust engines. We will be concerned with efficiency, where efficiency is evaluated in the case of the orbit-to-orbit transfer with maximum payload mass in the central Newtonian gravity field. The launch mass of the space vehicle is supposed to be fixed. The traditional solution is the decomposition of the problem into parametric and dynamical parts. The corresponding variational problems differ for two rocket thruster types under consideration. We propose change of variables, which makes it possible to reduce averaged equations of optimal motion of a spacecraft with the mentioned engines to the unified form. Using this unified form comparison of the performance of constant- and variable-thrust engines is conducted.

  6. Reliability and effective thermal conductivity of three metallic-ceramic composite insulating coatings on cooled hydrogen-oxygen rockets

    Science.gov (United States)

    Price, H. G., Jr.; Schacht, R. L.; Quentmeyer, R. J.

    1973-01-01

    An experimental investigation of the structural integrity and effective thermal conductivity of three metallic-ceramic composite coatings was conducted. These coatings were plasma sprayed onto the combustion side of water-cooled, 12.7-centimeter throat diameter, hydrogen-oxygen rocket thrust chambers operating at 2.07 to 4.14 meganewtons per square meter chamber pressure. The metallic-ceramic composites functioned for six to 17 cycles and for as long as 213 seconds of rocket operations and could have probably provided their insulating properties for many additional cycles. The effective thermal conductivity of all the coatings was in the range of 0.7472 to 4.483 w/(m)(K), which makes the coatings a very effective thermal barrier. Photomicrographic studies of cross-sectioned coolant tubes seem to indicate that the effective thermal conductivity of the coatings is controlled by contact resistance between the particles, as a result of the spraying process, and not the thermal conductivity of the bulk materials.

  7. Coil-On-Plug Ignition for LOX/Methane Liquid Rocket Engines in Thermal Vacuum Environments

    Science.gov (United States)

    Melcher, John C.; Atwell, Matthew J.; Morehead, Robert L.; Hurlbert, Eric A.; Bugarin, Luz; Chaidez, Mariana

    2017-01-01

    A coil-on-plug ignition system has been developed and tested for Liquid Oxygen (LOX) / liquid methane rocket engines operating in thermal vacuum conditions. The igniters were developed and tested as part of the Integrated Cryogenic Propulsion Test Article (ICPTA), previously tested as part of the Project Morpheus test vehicle. The ICPTA uses an integrated, pressure-fed, cryogenic LOX/methane propulsion system including a reaction control system (RCS) and a main engine. The ICPTA was tested at NASA Glenn Research Center's Plum Brook Station in the Spacecraft Propulsion Research Facility (B-2) under vacuum and thermal vacuum conditions. In order to successfully demonstrate ignition reliability in the vacuum conditions and eliminate corona discharge issues, a coil-on-plug ignition system has been developed. The ICPTA uses spark-plug ignition for both the main engine igniter and the RCS. The coil-on-plug configuration eliminates the conventional high-voltage spark plug cable by combining the coil and the spark-plug into a single component. Prior to ICPTA testing at Plum Brook, component-level reaction control engine (RCE) and main engine igniter testing was conducted at NASA Johnson Space Center (JSC), which demonstrated successful hot-fire ignition using the coil-on-plug from sea-level ambient conditions down to 10(exp.-2) torr. Integrated vehicle hot-fire testing at JSC demonstrated electrical and command/data system performance. Lastly, Plum Brook testing demonstrated successful ignitions at simulated altitude conditions at 30 torr and cold thermal-vacuum conditions at 6 torr. The test campaign successfully proved that coil-on-plug technology will enable integrated LOX/methane propulsion systems in future spacecraft.

  8. Heat transfer to throat tubes in a square-chambered rocket engine at the NASA Lewis Research Center

    Science.gov (United States)

    Nesbitt, James A.; Brindley, William J.

    1989-01-01

    A gaseous H2/O2 rocket engine was constructed at the NASA-Lewis to provide a high heat flux source representative of the heat flux to the blades in the high pressure fuel turbopump (HPFTP) during startup of the space shuttle main engines. The high heat flux source was required to evaluate the durability of thermal barrier coatings being investigated for use on these blades. The heat transfer, and specifically, the heat flux to tubes located at the throat of the test rocket engine was evaluated and compared to the heat flux to the blades in the HPFTP during engine startup. Gas temperatures, pressures and heat transfer coefficients in the test rocket engine were measured. Near surface metal temperatures below thin thermal barrier coatings were also measured at various angular orientations around the throat tube to indicate the angular dependence of the heat transfer coefficients. A finite difference model for a throat tube was developed and a thermal analysis was performed using the measured gas temperatures and the derived heat transfer coefficients to predict metal temperatures in the tube. Near surface metal temperatures of an uncoated throat tube were measured at the stagnation point and showed good agreement with temperatures predicted by the thermal model. The maximum heat flux to the throat tube was calculated and compared to that predicted for the leading edge of an HPFTP blade. It is shown that the heat flux to an uncooled throat tube is slightly greater than the heat flux to an HPFTP blade during engine startup.

  9. Laser rocket system analysis

    Science.gov (United States)

    Jones, W. S.; Forsyth, J. B.; Skratt, J. P.

    1979-01-01

    The laser rocket systems investigated in this study were for orbital transportation using space-based, ground-based and airborne laser transmitters. The propulsion unit of these systems utilizes a continuous wave (CW) laser beam focused into a thrust chamber which initiates a plasma in the hydrogen propellant, thus heating the propellant and providing thrust through a suitably designed nozzle and expansion skirt. The specific impulse is limited only by the ability to adequately cool the thruster and the amount of laser energy entering the engine. The results of the study showed that, with advanced technology, laser rocket systems with either a space- or ground-based laser transmitter could reduce the national budget allocated to space transportation by 10 to 345 billion dollars over a 10-year life cycle when compared to advanced chemical propulsion systems (LO2-LH2) of equal capability. The variation in savings depends upon the projected mission model.

  10. Rocket Engine System Analysis : Vinci Engine Turbines Analysis, Volvo Aero Corp.

    OpenAIRE

    Romanov, Artyom

    2008-01-01

    Major part of the current work describes the development of the update methodology for onedimensional code (TML) currently used at Volvo Aero Corporation during turbine design process. The methodology is then applied and tried out in a general engine analysis (GESTPAN).

  11. PNNL Development and Analysis of Material-Based Hydrogen Storage Systems for the Hydrogen Storage Engineering Center of Excellence

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Kriston P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Alvine, Kyle J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Kenneth I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Klymyshyn, Nicholas A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pires, Richard P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ronnebro, Ewa [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Simmons, Kevin L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weimar, Mark R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westman, Matthew P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-02-29

    The Hydrogen Storage Engineering Center of Excellence is a team of universities, industrial corporations, and federal laboratories with the mandate to develop lower-pressure, materials-based, hydrogen storage systems for hydrogen fuel cell light-duty vehicles. Although not engaged in the development of new hydrogen storage materials themselves, it is an engineering center that addresses engineering challenges associated with the currently available hydrogen storage materials. Three material-based approaches to hydrogen storage are being researched: 1) chemical hydrogen storage materials 2) cryo-adsorbents, and 3) metal hydrides. As a member of this Center, Pacific Northwest National Laboratory (PNNL) has been involved in the design and evaluation of systems developed with each of these three hydrogen storage materials. This report is a compilation of the work performed by PNNL for this Center.

  12. Integrated System Health Management: Pilot Operational Implementation in a Rocket Engine Test Stand

    Science.gov (United States)

    Figueroa, Fernando; Schmalzel, John L.; Morris, Jonathan A.; Turowski, Mark P.; Franzl, Richard

    2010-01-01

    This paper describes a credible implementation of integrated system health management (ISHM) capability, as a pilot operational system. Important core elements that make possible fielding and evolution of ISHM capability have been validated in a rocket engine test stand, encompassing all phases of operation: stand-by, pre-test, test, and post-test. The core elements include an architecture (hardware/software) for ISHM, gateways for streaming real-time data from the data acquisition system into the ISHM system, automated configuration management employing transducer electronic data sheets (TEDS?s) adhering to the IEEE 1451.4 Standard for Smart Sensors and Actuators, broadcasting and capture of sensor measurements and health information adhering to the IEEE 1451.1 Standard for Smart Sensors and Actuators, user interfaces for management of redlines/bluelines, and establishment of a health assessment database system (HADS) and browser for extensive post-test analysis. The ISHM system was installed in the Test Control Room, where test operators were exposed to the capability. All functionalities of the pilot implementation were validated during testing and in post-test data streaming through the ISHM system. The implementation enabled significant improvements in awareness about the status of the test stand, and events and their causes/consequences. The architecture and software elements embody a systems engineering, knowledge-based approach; in conjunction with object-oriented environments. These qualities are permitting systematic augmentation of the capability and scaling to encompass other subsystems.

  13. Oxidation Behavior of Copper Alloy Candidates for Rocket Engine Applications (Technical Poster)

    Science.gov (United States)

    Ogbuji, Linus U. J.; Humphrey, Donald H.; Barrett, Charles A.; Greenbauer-Seng, Leslie (Technical Monitor); Gray, Hugh R. (Technical Monitor)

    2002-01-01

    A rocket engine's combustion chamber is lined with material that is highly conductive to heat in order to dissipate the huge thermal load (evident in a white-hot exhaust plume). Because of its thermal conductivity copper is the best choice of liner material. However, the mechanical properties of pure copper are inadequate to withstand the high stresses, hence, copper alloys are needed in this application. But copper and its alloys are prone to oxidation and related damage, especially "blanching" (an oxidation-reduction mode of degradation). The space shuttle main engine combustion chamber is lined with a Cu-Ag-Zr alloy, "NARloy-Z", which exhibits blanching. A superior liner is being sought for the next generation of RLVs (Reusable Launch Vehicles) It should have improved mechanical properties and higher resistance to oxidation and blanching, but without substantial penalty in thermal conductivity. GRCop84, a Cu-8Cr-4Nb alloy (Cr2Nb in Cu matrix), developed by NASA Glenn Research Center (GRC) and Case Western Reserve University, is a prime contender for RLV liner material. In this study, the oxidation resistance of GRCop-84 and other related/candidate copper alloys are investigated and compared

  14. Fast reconstruction of an unmanned engineering vehicle and its application to carrying rocket

    Directory of Open Access Journals (Sweden)

    Jun Qian

    2014-04-01

    Full Text Available Engineering vehicle is widely used as a huge moving platform for transporting heavy goods. However, traditional human operations have a great influence on the steady movement of the vehicle. In this Letter, a fast reconstruction process of an unmanned engineering vehicle is carried out. By adding a higher-level controller and two two-dimensional laser scanners on the moving platform, the vehicle could perceive the surrounding environment and locate its pose according to extended Kalman filter. Then, a closed-loop control system is formed by communicating with the on-board lower-level controller. To verify the performance of automatic control system, the unmanned vehicle is automatically navigated when carrying a rocket towards a launcher in a launch site. The experimental results show that the vehicle could align with the launcher smoothly and safely within a small lateral deviation of 1 cm. This fast reconstruction presents an efficient way of rebuilding low-cost unmanned special vehicles and other automatic moving platforms.

  15. Genetic algorithm to optimize the design of main combustor and gas generator in liquid rocket engines

    Science.gov (United States)

    Son, Min; Ko, Sangho; Koo, Jaye

    2014-06-01

    A genetic algorithm was used to develop optimal design methods for the regenerative cooled combustor and fuel-rich gas generator of a liquid rocket engine. For the combustor design, a chemical equilibrium analysis was applied, and the profile was calculated using Rao's method. One-dimensional heat transfer was assumed along the profile, and cooling channels were designed. For the gas-generator design, non-equilibrium properties were derived from a counterflow analysis, and a vaporization model for the fuel droplet was adopted to calculate residence time. Finally, a genetic algorithm was adopted to optimize the designs. The combustor and gas generator were optimally designed for 30-tonf, 75-tonf, and 150-tonf engines. The optimized combustors demonstrated superior design characteristics when compared with previous non-optimized results. Wall temperatures at the nozzle throat were optimized to satisfy the requirement of 800 K, and specific impulses were maximized. In addition, the target turbine power and a burned-gas temperature of 1000 K were obtained from the optimized gas-generator design.

  16. Engineering analysis of potential photosynthetic bacterial hydrogen-production systems

    Science.gov (United States)

    Herlevich, A.; Karpuk, M. E.

    1982-06-01

    Photosynthetic bacteria (PSB) are capable of generating hydrogen from organics in effluents from food processing, pulp and paper, and chemical and pharmaceutical industries. Hydrogen evolution takes place under light in the absence of air. The rate of hydrogen production is expected to range between 300 to 600 scf of hydrogen per 1000 galloons of waste stream treated per hour. This hydrogen production system has been demonstrated at a bench-scale level and is ready for engineering development. A conceptual design for a PSB hydrogen production system is described. The system is expected to be sited adjacent to a waste stream source which will be pretreated by fermentation and pH adjustment, innoculated with bacteria, and then passed into the reactor. The reactor effluent can either be discharged into a rapid infiltration system, an irrigation ditch, and/or recycled back into the reactor. Several potential reactor designs have been developed, analyzed, and costed. A large covered pond appears to be the most economical design approach.

  17. Development and Hot-fire Testing of Additively Manufactured Copper Combustion Chambers for Liquid Rocket Engine Applications

    Science.gov (United States)

    Gradl, Paul R.; Greene, Sandy Elam; Protz, Christopher S.; Ellis, David L.; Lerch, Bradley A.; Locci, Ivan E.

    2017-01-01

    NASA and industry partners are working towards fabrication process development to reduce costs and schedules associated with manufacturing liquid rocket engine components with the goal of reducing overall mission costs. One such technique being evaluated is powder-bed fusion or selective laser melting (SLM), commonly referred to as additive manufacturing (AM). The NASA Low Cost Upper Stage Propulsion (LCUSP) program was designed to develop processes and material characterization for GRCop-84 (a NASA Glenn Research Center-developed copper, chrome, niobium alloy) commensurate with powder-bed AM, evaluate bimetallic deposition, and complete testing of a full scale combustion chamber. As part of this development, the process has been transferred to industry partners to enable a long-term supply chain of monolithic copper combustion chambers. To advance the processes further and allow for optimization with multiple materials, NASA is also investigating the feasibility of bimetallic AM chambers. In addition to the LCUSP program, NASA has completed a series of development programs and hot-fire tests to demonstrate SLM GRCop-84 and other AM techniques. NASA's efforts include a 4K lbf thrust liquid oxygen/methane (LOX/CH4) combustion chamber and subscale thrust chambers for 1.2K lbf LOX/hydrogen (H2) applications that have been designed and fabricated with SLM GRCop-84. The same technologies for these lower thrust applications are being applied to 25-35K lbf main combustion chamber (MCC) designs. This paper describes the design, development, manufacturing and testing of these numerous combustion chambers, and the associated lessons learned throughout their design and development processes.

  18. Improving the performance of LOX/kerosene upper stage rocket engines

    Directory of Open Access Journals (Sweden)

    IgorN. Nikischenko

    2017-09-01

    Full Text Available Improved liquid rocket engine cycles were proposed and analyzed via comparison with existing staged combustion and gas-generator cycles. The key features of the proposed cycles are regenerative cooling of thrust chamber by oxygen and subsequent use of this oxygen for driving one or two oxygen pumps. The fuel pump(s are driven in a conventional manner, for example, using a fuel-rich gas-generator cycle. Comparison with staged combustion cycle based on oxygen-rich pre-burner showed that one of the proposed semi-expander cycles has a specific impulse only on 0.4% lower while providing much lower oxygen temperature, more efficient tank pressurizing system and built-in roll control. This semi-expander cycle can be considered as a more reliable and cost-effective alternative of staged combustion cycle. Another semi-expander cycle can be considered as an improvement of gas-generator cycle. All proposed semi-expander cycles were developed as a derivative of thrust chamber regenerative cooling performed by oxygen. Analysis of existing oxygen/kerosene engines showed that replacing of kerosene regenerative cooling with oxygen allows a significant increase of achievable specific impulse, via optimization of mixture ratio. It is especially the case for upper stage engines. The increasing of propellants average density can be considered as an additional benefit of mixture ratio optimization. It was demonstrated that oxygen regenerative cooling of thrust chamber is a feasible and the most promising option for oxygen/kerosene engines. Combination of oxygen regenerative cooling and semi-expander cycles potentially allows creating the oxygen/kerosene propulsion systems with minimum specific impulse losses. It is important that such propulsion systems can be fully based on inherited and well-proven technical solutions. A hypothetic upper stage engine with thrust 19.6 kN was chosen as a prospective candidate for theoretical analysis of the proposed semi

  19. Modeling the effects of dissolved helium pressurant on a liquid hydrogen rocket propellant tank

    Science.gov (United States)

    Richardson, I. A.; Leachman, J. W.

    2017-12-01

    A model was developed using NASA’s Generalized Fluid System Simulation Program (GFSSP) for the self-pressurization of a liquid hydrogen propellant tank due to boil-off to determine the significance of mixture non-idealities. The GFSSP model compared the tank performance for the traditional model that assumes no helium pressurant dissolves into the liquid hydrogen propellant to an updated model that accounts for dissolved helium pressurant. Traditional NASA models have been unable to account for this dissolved helium due to a lack of fundamental property information. Recent measurements of parahydrogen-helium mixtures enabled the development of the first multi-phase Equation Of State (EOS) for parahydrogen-helium mixtures. The self-pressurization GFSSP model was run assuming that the liquid propellant was pure liquid hydrogen and assuming helium dissolved into the liquid utilizing the new helium-hydrogen EOS. The analysis shows that having dissolved helium in the propellant does not have a significant effect on the tank pressurization rate for typical tank conditions (-423 °F and 30 psia).

  20. Technology developments for thrust chambers of future launch vehicle liquid rocket engines

    Science.gov (United States)

    Immich, H.; Alting, J.; Kretschmer, J.; Preclik, D.

    2003-08-01

    In this paper an overview of recent technology developments for thrust chambers of future launch vehicle liquid rocket engines at Astrium, Space Infrastructure Division (SI), is shown. The main technology. developments shown in this paper are: Technologies Technologies for enhanced heat transfer to the coolant for expander cycle engines Advanced injector head technologies Advanced combustion chamber manufacturing technologies. The main technologies for enhanced heat transfer investigated by subscale chamber hot-firing tests are: Increase of chamber length Hot gas side ribs in the chamber Artificially increased surface roughness. The developments for advanced injector head technologies were focused on the design of a new modular subscale chamber injector head. This injector head allows for an easy exchange of different injection elements: By this, cost effective hot-fire tests with different injection element concepts can be performed. The developments for advanced combustion chamber manufacturing technologies are based on subscale chamber tests with a new design of the Astrium subscale chamber. The subscale chamber has been modified by introduction of a segmented cooled cylindrical section which gives the possibility to test different manufacturing concepts for cooled chamber technologies by exchanging the individual segments. The main technology efforts versus advanced manufacturing technologies shown in this paper are: Soldering techniques Thermal barrier coatings for increased chamber life. A new technology effort is dedicated especially to LOX/Hydrocarbon propellant combinations. Recent hot fire tests on the subscale chamber with Kerosene and Methane as fuel have already been performed. A comprehensive engine system trade-off between the both propellant combinations (Kerosene vs. Methane) is presently under preparation.

  1. Thermal Modelling of Various Thermal Barrier Coatings in a High Flux Rocket Engine

    Science.gov (United States)

    Nesbitt, James A.

    1998-01-01

    A thermal model was developed to predict the thermal response of coated and uncoated tubes tested in a H2/O2 rocket engine. Temperatures were predicted for traditional APS ZrO2-Y2O3 thermal barrier coatings, as well as APS and LPPS ZrO2-Y2O3/NiCrAlY cermet coatings. Good agreement was observed between predicted and measured metal temperatures at locations near the tube surface or at the inner tube wall. The thermal model was also used to quantitatively examine the effect of various coating system parameters on the temperatures in the substrate and coating. Accordingly, the effect of the presence a metallic bond coat and the effect of radiation from the surface of the ceramic layer were examined. In addition, the effect of a variation in the values of the thermal conductivity of the ceramic layer was also investigated. It was shown that a variation in the thermal conductivity of the ceramic layer, on the order of that reported in the literature for plasma sprayed ZrO2-Y2O3 coatings, can result in temperature differences in the substrate greater than 100 C, a much greater effect than that due to the presence of a bond coat or radiation from the ceramic layer. The thermal model was also used to predict the thermal response of a coated rod in order to quantify the difference in the metal temperatures between the two substrate geometries in order to explain the previously-observed increased life of coatings on rods over that on tubes. It was shown that for the short duration testing in the rocket engine, the temperature in a tube could exceed that in a rod by more than 100 C. Lastly, a two-dimensional model was developed to evaluate the effect of tangential heat transfer around the tube and its impact on reducing the stagnation point temperature. It was also shown that tangential heat transfer does not significantly reduce the stagnation point temperature, thus allowing application of a simpler, one-dimensional model for comparing measured and predicted stagnation point

  2. Cryogenic Propellant Storage and Transfer Engineering Development Unit Hydrogen Tank

    Science.gov (United States)

    Werkheiser, Arthur

    2015-01-01

    The Cryogenic Propellant Storage and Transfer (CPST) project has been a long-running program in the Space Technology Mission Directorate to enhance the knowledge and technology related to handling cryogenic propellants, specifically liquid hydrogen. This particular effort, the CPST engineering development unit (EDU), was a proof of manufacturability effort in support of a flight article. The EDU was built to find and overcome issues related to manufacturability and collect data to anchor the thermal models for use on the flight design.

  3. Recommended launch-hold criteria for protecting public health from hydrogen chloride (HC1) gas produced by rocket exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, J.I.; Baskett, R.L.

    1995-11-01

    Solid-fuel rocket motors used by the United States Air Force (USAF) to launch missiles and spacecraft can produce ambient-air concentrations of hydrogen chloride (HCI) gas. The HCI gas is a reaction product exhausted from the rocket motor during normal launch or emitted as a result of a catastrophic abort destroying the launch vehicle. Depending on the concentration in ambient air, the HCI gas can be irritating or toxic to humans. The diagnostic and complex-terrain wind field and particle dispersion model used by the Lawrence Livermore National Laboratory`s (LLNL`s) Atmospheric Release Advisory Capability (ARAC) Program was applied to the launch of a Peacekeeper missile from Vandenberg Air Force Base (VAFB) in California. Results from this deterministic model revealed that under specific meteorological conditions, cloud passage from normal-launch and catastropic-abort situations can yield measureable ground-level air concentrations of HCI where the general public is located. To protect public health in the event of such cloud passage, scientifically defensible, emergency ambient-air concentration limits for HCI were developed and recommended to the USAF for use as launch-hold criteria. Such launch-hold criteria are used to postpone a launch unless the forecasted meteorological conditions favor the prediction of safe ground-level concentrations of HCl for the general public. The recommended concentration limits are a 2 ppM 1-h time-weighted average (TWA) concentration constrained by a 1-min 10-ppM average concentration. This recommended criteria is supported by human dose-response information, including data for sensitive humans (e.g., asthmatics), and the dose response exhibited experimentally by animal models with respiratory physiology or responses considered similar to humans.

  4. Thermal/Fluid Analysis of a Composite Heat Exchanger for Use on the RLV Rocket Engine

    Science.gov (United States)

    Nguyen, Dalton

    2002-01-01

    As part of efforts to design a regeneratively cooled composite nozzle ramp for use on the reusable vehicle (RLV) rocket engine, an C-SiC composites heat exchanger concept was proposed for thermal performance evaluation. To test the feasibility of the concept, sample heat exchanger panels were made to fit the Glenn Research Center's cell 22 for testing. Operation of the heat exchanger was demonstrated in a combustion environment with high heat fluxes similar to the RLV Aerospike Ramp. Test measurements were reviewed and found to be valuable for the on going fluid and thermal analysis of the actual RLV composite ramp. Since the cooling fluid for the heat exchanger is water while the RLV Ramp cooling fluid is LH2, fluid and thermal models were constructed to correlate to the specific test set-up. The knowledge gained from this work will be helpful for analyzing the thermal response of the actual RLV Composite Ramp. The coolant thermal properties for the models are taken from test data. The heat exchanger's cooling performance was analyzed using the Generalized Fluid System Simulation Program (GFSSP). Temperatures of the heat exchanger's structure were predicted in finite element models using Patran and Sinda. Results from the analytical models and the tests show that RSC's heat exchanger satisfied the combustion environments in a series of 16 tests.

  5. Highly resolved numerical simulation of combustion downstream of a rocket engine igniter

    Science.gov (United States)

    Buttay, R.; Gomet, L.; Lehnasch, G.; Mura, A.

    2017-07-01

    We study ignition processes in the turbulent reactive flow established downstream of highly under-expanded coflowing jets. The corresponding configuration is typical of a rocket engine igniter, and to the best knowledge of the authors, this study is the first that documents highly resolved numerical simulations of such a reactive flowfield. Considering the discharge of axisymmetric coaxial under-expanded jets, various morphologies are expected, depending on the value of the nozzle pressure ratio, a key parameter used to classify them. The present computations are conducted with a value of this ratio set to fifteen. The simulations are performed with the massively parallel CREAMS solver on a grid featuring approximately 440,000,000 computational nodes. In the main zone of interest, the level of spatial resolution is D/74, with D the central inlet stream diameter. The computational results reveal the complex topology of the compressible flowfield. The obtained results also bring new and useful insights into the development of ignition processes. In particular, ignition is found to take place rather far downstream of the shock barrel, a conclusion that contrasts with early computational studies conducted within the unsteady RANS computational framework. Consideration of detailed chemistry confirms the essential role of hydroperoxyl radicals, while the analysis of the Takeno index reveals the predominance of a non-premixed combustion mode.

  6. Experimental investigation of high-frequency combustion instabilities in liquid rocket engine

    Science.gov (United States)

    Richecoeur, F.; Ducruix, S.; Scouflaire, P.; Candel, S.

    2008-01-01

    High-frequency instabilities in liquid propellant rocket engines are experimentally investigated in a model scale research facility. Liquid oxygen and gaseous methane are injected in the combustion chamber at 0.9 MPa through three coaxial injectors vertically aligned. High-amplitude transverse pressure fluctuations are generated in the chamber at frequencies above 1 kHz by a rotating toothed wheel actuator which periodically blocks an auxiliary lateral nozzle. The chamber eigenmodes are identified in a first stage by examining the response of the system to a linear frequency sweep. In a second stage the chamber is excited at the frequency corresponding to the first transverse (1T) mode. The effect of the pressure mode on combustion is observed with intensified and high-speed cameras. Photo-multipliers and pressure sensors are also used to characterize the system behavior and examine phase relations between the corresponding signals. Flame structure modifications observed for specific injection conditions correspond to a strong coupling between acoustics and combustion which notably modifies the flow dynamics, augments the flame expansion rate and enhances heat transfer to the wall.

  7. Method and apparatus to produce high specific impulse and moderate thrust from a fusion-powered rocket engine

    Science.gov (United States)

    Cohen, Samuel A.; Pajer, Gary A.; Paluszek, Michael A.; Razin, Yosef S.

    2017-11-21

    A system and method for producing and controlling high thrust and desirable specific impulse from a continuous fusion reaction is disclosed. The resultant relatively small rocket engine will have lower cost to develop, test, and operate that the prior art, allowing spacecraft missions throughout the planetary system and beyond. The rocket engine method and system includes a reactor chamber and a heating system for heating a stable plasma to produce fusion reactions in the stable plasma. Magnets produce a magnetic field that confines the stable plasma. A fuel injection system and a propellant injection system are included. The propellant injection system injects cold propellant into a gas box at one end of the reactor chamber, where the propellant is ionized into a plasma. The propellant and fusion products are directed out of the reactor chamber through a magnetic nozzle and are detached from the magnetic field lines producing thrust.

  8. High Thermal Conductivity NARloy-Z-Diamond Composite Liner for Advanced Rocket Engines

    Science.gov (United States)

    Bhat, Biliyar; Greene, Sandra

    2015-01-01

    NARloy-Z (Cu-3Ag-0.5Zr) alloy is state-of-the-art combustion chamber liner material used in liquid propulsion engines such as the RS-68 and RS-25. The performance of future liquid propulsion systems can be improved significantly by increasing the heat transfer through the combustion chamber liner. Prior work1 done at NASA Marshall Space Flight Center (MSFC) has shown that the thermal conductivity of NARloy-Z alloy can be improved significantly by embedding high thermal conductivity diamond particles in the alloy matrix to form NARloy-Z-diamond composite (fig. 1). NARloy-Z-diamond composite containing 40vol% diamond showed 69% higher thermal conductivity than NARloy-Z. It is 24% lighter than NARloy-Z and hence the density normalized thermal conductivity is 120% better. These attributes will improve the performance and life of the advanced rocket engines significantly. The research work consists of (a) developing design properties (thermal and mechanical) of NARloy-Z-D composite, (b) fabrication of net shape subscale combustion chamber liner, and (c) hot-fire testing of the liner to test performance. Initially, NARloy-Z-D composite slabs were made using the Field Assisted Sintering Technology (FAST) for the purpose of determining design properties. In the next step, a cylindrical shape was fabricated to demonstrate feasibility (fig. 3). The liner consists of six cylinders which are sintered separately and then stacked and diffusion bonded to make the liner (fig. 4). The liner will be heat treated, finish-machined, and assembled into a combustion chamber and hot-fire tested in the MSFC test facility (TF 115) to determine perform.

  9. Rockets in World War I

    Science.gov (United States)

    2004-01-01

    World War I enlisted rockets once again for military purposes. French pilots rigged rockets to the wing struts of their airplanes and aimed them at enemy observation balloons filled with highly inflammable hydrogen.

  10. Low-Cost High-Performance Non-Toxic Self-Pressurizing Storable Liquid Bi-Propellant Pressure-Fed Rocket Engine Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Exquadrum proposes a high-performance liquid bi-propellant rocket engine that uses propellants that are non-toxic, self-pressurizing, and low cost. The proposed...

  11. Hazards Induced by Breach of Liquid Rocket Fuel Tanks: Conditions and Risks of Cryogenic Liquid Hydrogen-Oxygen Mixture Explosions

    Science.gov (United States)

    Osipov, Viatcheslav; Muratov, Cyrill; Hafiychuk, Halyna; Ponizovskya-Devine, Ekaterina; Smelyanskiy, Vadim; Mathias, Donovan; Lawrence, Scott; Werkheiser, Mary

    2011-01-01

    We analyze the data of purposeful rupture experiments with LOx and LH2 tanks, the Hydrogen-Oxygen Vertical Impact (HOVI) tests that were performed to clarify the ignition mechanisms, the explosive power of cryogenic H2/Ox mixtures under different conditions, and to elucidate the puzzling source of the initial formation of flames near the intertank section during the Challenger disaster. We carry out a physics-based analysis of general explosions scenarios for cryogenic gaseous H2/Ox mixtures and determine their realizability conditions, using the well-established simplified models from the detonation and deflagration theory. We study the features of aerosol H2/Ox mixture combustion and show, in particular, that aerosols intensify the deflagration flames and can induce detonation for any ignition mechanism. We propose a cavitation-induced mechanism of self-ignition of cryogenic H2/Ox mixtures that may be realized when gaseous H2 and Ox flows are mixed with a liquid Ox turbulent stream, as occurred in all HOVI tests. We present an overview of the HOVI tests to make conclusion on the risk of strong explosions in possible liquid rocket incidents and provide a semi-quantitative interpretation of the HOVI data based on aerosol combustion. We uncover the most dangerous situations and discuss the foreseeable risks which can arise in space missions and lead to tragic outcomes. Our analysis relates to only unconfined mixtures that are likely to arise as a result of liquid propellant space vehicle incidents.

  12. Reuse fo a Cold War Surveillance Drone to Flight Test a NASA Rocket Based Combined Cycle Engine

    Science.gov (United States)

    Brown, T. M.; Smith, Norm

    1999-01-01

    Plans for and early feasibility investigations into the modification of a Lockheed D21B drone to flight test the DRACO Rocket Based Combined Cycle (RBCC) engine are discussed. Modifications include the addition of oxidizer tanks, modern avionics systems, actuators, and a vehicle recovery system. Current study results indicate that the D21B is a suitable candidate for this application and will allow demonstrations of all DRACO engine operating modes at Mach numbers between 0.8 and 4.0. Higher Mach numbers may be achieved with more extensive modification. Possible project risks include low speed stability and control, and recovery techniques.

  13. Preliminary Design Study of Main Rocket Engine for SpaceLiner High-Speed Passenger Transportation Concept

    OpenAIRE

    Sippel, Martin; Yamashiro, Ryoma

    2013-01-01

    The revolutionary ultrafast passenger transportation system SpaceLiner is under investigation at DLR in the EU-funded study Future high-Altitude high-Speed Transport 20XX. SpaceLiner’s configuration is being amended continuously, and SpaceLiner7 is the brand new version at the point of April in 2013. SpaceLiner7 is two staged reusable launch vehicle with liquid rocket engines. SpaceLiner Main Engine (SLME) is required to have high performance for the total system to be feasible, a...

  14. PRELIMINARY DESIGN STUDY OF STAGED COMBUSTION CYCLE ROCKET ENGINE FOR SPACELINER HIGH-SPEED PASSENGER TRANSPORTATION CONCEPT

    OpenAIRE

    Yamashiro, Ryoma; Sippel, Martin

    2012-01-01

    The revolutionary ultrafast passenger transportation system SpaceLiner is under investigation at DLR in the EU-funded study Future high-Altitude high-Speed Transport 20XX. SpaceLiner’s configuration is being amended continuously, and SpaceLiner7 is the brand new version at the point of August in 2012. SpaceLiner7 is two staged reusable launch vehicle with liquid rocket engines. SpaceLiner Main Engine (SLME) is required to have high performance for the total system to be feasible, and also to ...

  15. Liquid rocket propulsion dynamic flow modeling using the ROCETS engineering modules in the EASY5x environment

    Science.gov (United States)

    Follett, Randolph F.; Taylor, Robert P.; Nunez, Stephen C.

    1993-01-01

    A report on the progress of porting the ROCETS (ROCket Engine Transient Simulator) into the EASY5x simulation environment is presented. Brief descriptions of each of the software systems, information regarding the actual port process, and examples comparing the results of the two systems are given. It is shown that EASY5x is a suitable environment for utilization of the ROCETS engineering modules, and that, for the example systems shown, EASY5x actually seems to give more accurate solutions than the straight ROCETS code.

  16. Enantioselective synthesis of aziridines using asymmetric transfer hydrogenation as a precursor for chiral derivatives used as bonding agent for rocket solid propellants

    Directory of Open Access Journals (Sweden)

    Aparecida M. Kawamoto

    2002-11-01

    Full Text Available A rapid, expedient and enantioselective method for the synthesis of beta-hydroxy amines and monosubstituted aziridines in up to 99% e.e., via asymmetric transfer hydrogenation of a-amino ketones and cyclisation through treatment with tosyl chloride and base, is described. (1R,2R-N-(para-toluenesulfonyl-1,2-ethylenediamine with formic acid has been utilised as a ligand for the Ruthenium (II catalysed enantioselective transfer hydrogenation of the ketones.The chiral 2-methyl aziridine, which is a potentially more efficient bonding agent for Rocket Solid Propellant has been successfully achieved.

  17. Hydrogen-bonding directed crystal engineering of some molecular solids

    Science.gov (United States)

    Xue, Feng

    2000-10-01

    The design of crystalline clathrates and microporous solids is a contemporary goal in crystal engineering, in which hydrogen bonds play a central role because of their strength, directionality and flexibility. We have constructed various layer- and channel-type host structures by using hydrogen-bonding interactions. A novel hydrogen-bonded supramolecular rosette structure is generated from guanidinium and hydrogen carbonate ions in (1) and ( 2). The rosettes are fused into linear ribbons, which are cross-linked by terephthalate or 4-nitrobenzoate ions functioning as hydrogen-bond acceptors, resulting in anionic host layers with tetra-n-butylammonium guest species sandwiched between them. In (3) ˜ (6), new crystalline adducts of tetraalkylammonium terephthalate/trimesate with urea and water molecules result from hydrogen-bond directed assembly of complementary acceptors and donors that generate anionic channel- and layer-type host lattices for the accommodation of bulky hydrophobic cations. Some 4,4'-disubstituted biphenyls manifest their robustness and flexibility as supramolecular building blocks to construct host structures. 4,4'-biphenyl dicarboxylate ion has a strong tendency in generating ladder-type structure in (7) ˜ (10) due to its rigidity and effectiveness as a bifunctional hydrogen-bond acceptor. In (11) ˜ (15), 4,4 '-dicyanobiphenyl, 4,4'-bipyridine-N,N '-dioxide and 4,4'-dinitrobiphenyl exhibit a constructive interplay of strong and weak hydrogen bond functionalities that generate robust synthons. 4-Tritylbenzoic acid crystallizes via the carboxyl dimer supramolecular synthon to produce a wheel-and-axle host lattice that includes different aromatic solvents in its microporous framework in (16) ˜ (25 ), in which the host architecture is robust and yet adaptive. Based on the trigonal symmetry of 2,4,6-tris-4-(halo-phenoxy)-1,3,5-triazines (halo = chloro, bromo) and the Br3 or Cl3 supramolecular synthon, a new hexagonal host lattice has been designed

  18. Combustion Experiment to Evaluate a LOX Vaporization Nozzle for a Swirling-Oxidizer-Flow-Type Hybrid Rocket Engine with a 1500N-Thrust

    Science.gov (United States)

    Kitagawa, Koki; Sakurazawa, Toshiaki; Yuasa, Saburo

    The authors have proposed a LOX vaporization nozzle for swirling-oxidizer-flow-type hybrid rocket engines to increase engine performance. In this study, we developed the LOX vaporization nozzle for this type of a hybrid rocket engine with a 1500N-thrust. Vaporization experiments, using a LOX supply system for the nozzle to be independent of a GOX supply system for the engine, were conducted. The test runs at little oxygen mass flow rates and low combustion pressures at the design point showed that LOX could be vaporized safely through the nozzle. It was confirmed that the design of the LOX vaporization nozzle was proper. Vaporization and burning experiments using vaporized O2 through the LOX vaporization nozzle showed that reliable and rapid ignition and stable combustion without combustion oscillation were achieved. The LOX vaporization nozzle increased the engine performance of the swirling-oxidizer- flow-type hybrid rocket engine.

  19. Using Decision Trees to Detect and Isolate Simulated Leaks in the J-2X Rocket Engine

    Science.gov (United States)

    Schwabacher, Mark A.; Aguilar, Robert; Figueroa, Fernando F.

    2009-01-01

    The goal of this work was to use data-driven methods to automatically detect and isolate faults in the J-2X rocket engine. It was decided to use decision trees, since they tend to be easier to interpret than other data-driven methods. The decision tree algorithm automatically "learns" a decision tree by performing a search through the space of possible decision trees to find one that fits the training data. The particular decision tree algorithm used is known as C4.5. Simulated J-2X data from a high-fidelity simulator developed at Pratt & Whitney Rocketdyne and known as the Detailed Real-Time Model (DRTM) was used to "train" and test the decision tree. Fifty-six DRTM simulations were performed for this purpose, with different leak sizes, different leak locations, and different times of leak onset. To make the simulations as realistic as possible, they included simulated sensor noise, and included a gradual degradation in both fuel and oxidizer turbine efficiency. A decision tree was trained using 11 of these simulations, and tested using the remaining 45 simulations. In the training phase, the C4.5 algorithm was provided with labeled examples of data from nominal operation and data including leaks in each leak location. From the data, it "learned" a decision tree that can classify unseen data as having no leak or having a leak in one of the five leak locations. In the test phase, the decision tree produced very low false alarm rates and low missed detection rates on the unseen data. It had very good fault isolation rates for three of the five simulated leak locations, but it tended to confuse the remaining two locations, perhaps because a large leak at one of these two locations can look very similar to a small leak at the other location.

  20. The Evaluation of High Temperature Adhesive Bonding Processes for Rocket Engine Combustion Chamber Applications

    Science.gov (United States)

    McCray, Daniel; Smith, Jeffrey; Rice, Brian; Blohowiak, Kay; Anderson, Robert; Shin, E. Eugene; McCorkle, Linda; Sutter, James

    2003-01-01

    NASA Glenn Research Center is currently evaluating the possibility of using high- temperature polymer matrix composites to reinforce the combustion chamber of a rocket engine. One potential design utilizes a honeycomb structure composed of a PMR-II- 50/M40J 4HS composite facesheet and titanium honeycomb core to reinforce a stainless steel shell. In order to properly fabricate this structure, adhesive bond PMR-II-50 composite. Proper prebond surface preparation is critical in order to obtain an acceptable adhesive bond. Improperly treated surfaces will exhibit decreased bond strength and durability, especially in metallic bonds where interface are susceptible to degradation due to heat and moisture. Most treatments for titanium and stainless steel alloys require the use of strong chemicals to etch and clean the surface. This processes are difficult to perform due to limited processing facilities as well as safety and environmental risks and they do not consistently yield optimum bond durability. Boeing Phantom Works previously developed sol-gel surface preparations for titanium alloys using a PETI-5 based polyimide adhesive. In support of part of NASA Glenn Research Center, UDRI and Boeing Phantom Works evaluated variations of this high temperature sol-gel surface preparation, primer type, and primer cure conditions on the adhesion performance of titanium and stainless steel using Cytec FM 680-1 polyimide adhesive. It was also found that a modified cure cycle of the FM 680-1 adhesive, i.e., 4 hrs at 370 F in vacuum + post cure, significantly increased the adhesion strength compared to the manufacturer's suggested cure cycle. In addition, the surface preparation of the PMR-II-50 composite was evaluated in terms of surface cleanness and roughness. This presentation will discuss the results of strength and durability testing conducted on titanium, stainless steel, and PMR-II-50 composite adherends to evaluate possible bonding processes.

  1. Experimental hydrogen-fueled automotive engine design data-base project. Volume 2. Main technical report

    Energy Technology Data Exchange (ETDEWEB)

    Swain, M.R.; Adt, R.R. Jr.; Pappas, J.M.

    1983-05-01

    Operational performance and emissions characteristics of hydrogen-fueled engines are reviewed. The project activities are reviewed including descriptions of the test engine and its components, the test apparatus, experimental techniques, experiments performed and the results obtained. Analyses of other hydrogen engine project data are also presented and compared with the results of the present effort.

  2. Improving of technical characteristics of launch vehicles with liquid rocket engines using active onboard de-orbiting systems

    Science.gov (United States)

    Trushlyakov, V.; Shatrov, Ya.

    2017-09-01

    In this paper, the analysis of technical requirements (TR) for the development of modern space launch vehicles (LV) with main liquid rocket engines (LRE) is fulfilled in relation to the anthropogenic impact decreasing. Factual technical characteristics on the example of a promising type of rocket ;Soyuz-2.1.v.; are analyzed. Meeting the TR in relation to anthropogenic impact decrease based on the conventional design approach and the content of the onboard system does not prove to be efficient and leads to depreciation of the initial technical characteristics obtained at the first design stage if these requirements are not included. In this concern, it is shown that the implementation of additional active onboard de-orbiting system (AODS) of worked-off stages (WS) into the onboard LV stages systems allows to meet the TR related to the LV environmental characteristics, including fire-explosion safety. In some cases, the orbital payload mass increases.

  3. Experimental Performance of Area Ratio 200, 25 and 8 Nozzles on JP-4 Fuel and Liquid Oxygen Rocket Engine

    Science.gov (United States)

    Lovell, J. Calvin; Samanich, Nick E.; Barnett, Donald O.

    1960-01-01

    The performance of an area ratio 200 bell-shaped nozzle, an area ratio 25 bell-shaped nozzle, and an area ratio 8 conic nozzle on a JP-4 fuel and liquid-oxygen rocket engine has been determined. Tests were conducted using a nominal 4000-pound-thrust rocket in the Lewis 10- by 10-foot supersonic tunnel, which provided the altitude environment needed for fully expanded nozzle flow. The area ratio 200 nozzle had a vacuum thrust coefficient of 1.96, compared with 1.82 and 1.70 for the area ratio 25 and 8 nozzles, respectively. These values are approximately equal to those for theoretical frozen expansion. The measured value of vacuum specific impulse for the area ratio 200 nozzle was 317 seconds for a combustion-chamber characteristic velocity of 5200 feet per second. The vacuum-specific-impulse increase for the area-ratio increase from 8 to 200 was 46 seconds.

  4. Hydrogen Storage Engineering Center of Excellence Metal Hydride Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Motyka, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-05-31

    The Hydrogen Storage Engineering Center of Excellence (HSECoE) was established in 2009 by the U.S. Department of Energy (DOE) to advance the development of materials-based hydrogen storage systems for hydrogen-fueled light-duty vehicles. The overall objective of the HSECoE is to develop complete, integrated system concepts that utilize reversible metal hydrides, adsorbents, and chemical hydrogen storage materials through the use of advanced engineering concepts and designs that can simultaneously meet or exceed all the DOE targets. This report describes the activities and accomplishments during Phase 1 of the reversible metal hydride portion of the HSECoE, which lasted 30 months from February 2009 to August 2011. A complete list of all the HSECoE partners can be found later in this report but for the reversible metal hydride portion of the HSECoE work the major contributing organizations to this effort were the United Technology Research Center (UTRC), General Motors (GM), Pacific Northwest National Laboratory (PNNL), the National Renewable Energy Laboratory (NREL) and the Savannah River National Laboratory (SRNL). Specific individuals from these and other institutions that supported this effort and the writing of this report are included in the list of contributors and in the acknowledgement sections of this report. The efforts of the HSECoE are organized into three phases each approximately 2 years in duration. In Phase I, comprehensive system engineering analyses and assessments were made of the three classes of storage media that included development of system level transport and thermal models of alternative conceptual storage configurations to permit detailed comparisons against the DOE performance targets for light-duty vehicles. Phase 1 tasks also included identification and technical justifications for candidate storage media and configurations that should be capable of reaching or exceeding the DOE targets. Phase 2 involved bench-level testing and

  5. A Rocket Powered Single-Stage-to-Orbit Launch Vehicle With U.S. and Soviet Engineers

    Science.gov (United States)

    MacConochie, Ian O.; Stnaley, Douglas O.

    1991-01-01

    A single-stage-to-orbit launch vehicle is used to assess the applicability of Soviet Energia high-pressure-hydrocarbon engine to advanced U.S. manned space transportation systems. Two of the Soviet engines are used with three Space Shuttle Main Engines. When applied to a baseline vehicle that utilized advanced hydrocarbon engines, the higher weight of the Soviet engines resulted in a 20 percent loss of payload capability and necessitated a change in the crew compartment size and location from mid-body to forebody in order to balance the vehicle. Various combinations of Soviet and Shuttle engines were evaluated for comparison purposes, including an all hydrogen system using all Space Shuttle Main Engines. Operational aspects of the baseline vehicle are also discussed. A new mass properties program entitles Weights and Moments of Inertia (WAMI) is used in the study.

  6. The Pressure Field Measurement for Researching Inducer Flow of Booster Rocket Engine Turbopump

    Directory of Open Access Journals (Sweden)

    N. S. Dorosh

    2014-01-01

    Full Text Available When designing a feed system for modern main rocket engine development, designers have to pay special attention to energy efficiency of units and their reliability. One of the most important conditions of reliability is to provide non-cavitation operation of the main turbo-pump, which is impossible without using the booster turbo-pumps, considering the current levels of pressure in the combustion chamber. Thanks to high suction properties and processability, axial inducers with screw geometry became the most widely used in booster turbo-pumps. At the same time, the flow in the inducers of progressive geometry has complex spatial nature that makes their designing and detailed flow studying to be a difficult task.Based on the need of detailed understanding the flow structure in inducer channels a number of investigation methods are considered, including: analytical calculation, visual research methods, direct flow measurement, and numerical simulation. Analysis of the characteristics of each method shows the need to combine several methods to achieve the best results. Using a numerical simulation becomes the most effective strategy to obtain a wide range of data and confirm their authenticity by experimental measurements at characteristic points. The features of such kind of measurements in the inducer flow and measuring device requirements are considered.Based on this, an original design experimental booster turbo-pump, equipped with a pressure measuring system behind the inducer and automatic unloader device simulator is developed. Using these systems a radial pressure diagram of inducer flow as well as axial the force acting on the inducer can be experimentally obtained. It is shown that the offered measuring system satisfies those requirements and provides data at the various operation modes of the booster turbopump unit. A developed test program allows us to obtain required data: the pressure values in the flow behind inducer and axial force

  7. Copper-Multiwall Carbon Nanotubes and Copper-Diamond Composites for Advanced Rocket Engines

    Science.gov (United States)

    Bhat, Biliyar N.; Ellis, Dave L.; Smelyanskiy, Vadim; Foygel, Michael; Rape, Aaron; Singh, Jogender; Vohra, Yogesh K.; Thomas, Vinoy; Otte, Kyle G.; Li, Deyu

    2013-01-01

    This paper reports on the research effort to improve the thermal conductivity of the copper-based alloy NARloy-Z (Cu-3 wt.%Ag-0.5 wt.% Zr), the state-of-the-art alloy used to make combustion chamber liners in regeneratively-cooled liquid rocket engines, using nanotechnology. The approach was to embed high thermal conductivity multiwall carbon nanotubes (MWCNTs) and diamond (D) particles in the NARloy-Z matrix using powder metallurgy techniques. The thermal conductivity of MWCNTs and D have been reported to be 5 to 10 times that of NARloy-Z. Hence, 10 to 20 vol. % MWCNT finely dispersed in NARloy-Z matrix could nearly double the thermal conductivity, provided there is a good thermal bond between MWCNTs and copper matrix. Quantum mechanics-based modeling showed that zirconium (Zr) in NARloy-Z should form ZrC at the MWCNT-Cu interface and provide a good thermal bond. In this study, NARloy-Z powder was blended with MWCNTs in a ball mill, and the resulting mixture was consolidated under high pressure and temperature using Field Assisted Sintering Technology (FAST). Microstructural analysis showed that the MWCNTs, which were provided as tangles of MWCNTs by the manufacturer, did not detangle well during blending and formed clumps at the prior particle boundaries. The composites made form these powders showed lower thermal conductivity than the base NARloy-Z. To eliminate the observed physical agglomeration, tangled multiwall MWCNTs were separated by acid treatment and electroless plated with a thin layer of chromium to keep them separated during further processing. Separately, the thermal conductivities of MWCNTs used in this work were measured, and the results showed very low values, a major factor in the low thermal conductivity of the composite. On the other hand, D particles embedded in NARloy-Z matrix showed much improved thermal conductivity. Elemental analysis showed migration of Zr to the NARloy-Z-D interface to form ZrC, which appeared to provide a low contact

  8. Copper Multiwall Carbon Nanotubes and Copper-Diamond Composites for Advanced Rocket Engines

    Science.gov (United States)

    Bhat, Biliyar N.; Ellis, Dave L.; Smelyanskiy, Vadim; Foygel, Michael; Singh, Jogender; Rape, Aaron; Vohra, Yogesh; Thomas, Vinoy; Li, Deyu; Otte, Kyle

    2013-01-01

    This paper reports on the research effort to improve the thermal conductivity of the copper-based alloy NARloy-Z (Cu-3 wt.%Ag-0.5 wt.% Zr), the state-of-the-art alloy used to make combustion chamber liners in regeneratively-cooled liquid rocket engines, using nanotechnology. The approach was to embed high thermal conductivity multiwall carbon nanotubes (MWCNTs) and diamond (D) particles in the NARloy-Z matrix using powder metallurgy techniques. The thermal conductivity of MWCNTs and D have been reported to be 5 to 10 times that of NARloy-Z. Hence, 10 to 20 vol. % MWCNT finely dispersed in NARloy-Z matrix could nearly double the thermal conductivity, provided there is a good thermal bond between MWCNTs and copper matrix. Quantum mechanics-based modeling showed that zirconium (Zr) in NARloy-Z should form ZrC at the MWCNT-Cu interface and provide a good thermal bond. In this study, NARloy-Z powder was blended with MWCNTs in a ball mill, and the resulting mixture was consolidated under high pressure and temperature using Field Assisted Sintering Technology (FAST). Microstructural analysis showed that the MWCNTs, which were provided as tangles of MWCNTs by the manufacturer, did not detangle well during blending and formed clumps at the prior particle boundaries. The composites made form these powders showed lower thermal conductivity than the base NARloy-Z. To eliminate the observed physical agglomeration, tangled multiwall MWCNTs were separated by acid treatment and electroless plated with a thin layer of chromium to keep them separated during further processing. Separately, the thermal conductivities of MWCNTs used in this work were measured, and the results showed very low values, a major factor in the low thermal conductivity of the composite. On the other hand, D particles embedded in NARloy-Z matrix showed much improved thermal conductivity. Elemental analysis showed migration of Zr to the NARloy-Z-D interface to form ZrC, which appeared to provide a low contact

  9. STUDIES AND RESEARCHES CONCERNING THE POSSIBILITY OF USING HYDROGEN IN TURBO ENGINES

    Directory of Open Access Journals (Sweden)

    Marius BIBU

    2014-10-01

    Full Text Available The paper aims to study the main aspects related to using Hydrogen as fuel in thermal engines, the advantages and disadvantages of using it as fuel and the technical posibilities of adjusting it, Hydrogen used as supplement at the main fuel and Hydrogen used as working fluid. As a perspective, it can be considered using Hydrogen as thermical agent in a closed energetic flux with thermo- chemical compression of Hydrogen in a hybrid heat changer, based on the heat of burning products of thermical engines. The experiments made showed that using such a way of using the heat of burning products of turbo engines can assure the increase of power and efficiency of the whole instalation with 20 %, which make us consider Hydrogen as a viable and advantageous alternative of fuel to be used in turbo engines and other engines.

  10. Rotating and positive-displacement pumps for low-thrust rocket engines. Volume 2: Fabrication and testing

    Science.gov (United States)

    Csomor, A.

    1974-01-01

    Rotating and positive displacement pumps of various types were studied for pumping liquid fluorine for low thrust high performance rocket engines. Included in the analysis were: centrifugal, pitot, Barske, Tesla, drag, gear, vane, axial piston, radial piston, diaphragm and helirotor pump concepts. The centrifugal and gear pumps were carried through detail design and fabrication. After preliminary testing in Freon 12, the centrifugal pump was selected for further testing and development. It was tested in Freon 12 to obtain the hydrodynamic performance. Tests were also conducted in liquid fluorine to demonstrate chemical compatibility.

  11. Concerning the problem of dynamic damping of the vibration combustion self-oscillations in a liquid-propellant rocket engine

    Science.gov (United States)

    Basok, B. I.; Gotsulenko, V. V.; Gotsulenko, V. N.

    2012-11-01

    The reason for the decrease in the amplitude of longitudinal vibration combustion self-oscillations in the combustion chamber of a liquid-propellant rocket engine by means of antipulse partitions has been justified. A mathematical model of the development of combustion instability in such a chamber on attachment of a Helmholtz resonator to it has been obtained. The character of the damping of vibration combustion self-oscillations excited by the action of the Crocco mechanisms and negative thermal resistance, when varying the acoustic parameters of the resonator and of the pressure head characteristics of combustion chamber is established.

  12. Recent Experimental Efforts on High-Pressure Supercritical Injection for Liquid Rockets and Their Implications

    OpenAIRE

    Chehroudi, Bruce

    2012-01-01

    Pressure and temperature of the liquid rocket thrust chambers into which propellants are injected have been in an ascending trajectory to gain higher specific impulse. It is quite possible then that the thermodynamic condition into which liquid propellants are injected reaches or surpasses the critical point of one or more of the injected fluids. For example, in cryogenic hydrogen/oxygen liquid rocket engines, such as Space Shuttle Main Engine (SSME) or Vulcain (Ariane 5), the injected li...

  13. Processes during the hypergolic ignition between monomethylhydrazine (MMH) and dinitrogen tetroxide (N{sub 2}O{sub 4}) in rocket engines

    Energy Technology Data Exchange (ETDEWEB)

    Frank, Irmgard; Hammerl, Anton; Klapoetke, Thomas M.; Nonnenberg, Christel [Chair of Inorganic Chemistry, Ludwig-Maximilian University of Munich, Butenandtstr. 5-13 (D), D-81377 Munich (Germany); Zewen, Helmut [EADS Space Transportation, D-81663 Munich (Germany)

    2005-02-01

    Two potential sources for engine complications with methylhydrazine/nitrogen tetroxide rocket engines were examined. The products formed during a cold pre-reaction before the actual ignition of the rocket engine and their later behavior were investigated with Car-Parrinello molecular dynamics simulations. It was found that methyldiazene is the main product of the cold pre-reaction. As a side product, especially in the presence of an excess of methylhydrazine, dimethyltetrazanes are formed. These may be responsible for violent side reactions. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  14. Numerical investigation of the influence of crystallization of ultrafine particles of aluminum oxide on energy characteristics of solid-propellant rocket engine

    Science.gov (United States)

    Dyachenko, N. N.; Dyachenko, L. I.

    2014-08-01

    The results of numerical investigation of a multiphase flow considering coagulation, crushing and crystallization of the particles of polydispersed condensate in the nozzles of solid-propellant rocket engine are presented. The influence of particles crystallization on the energy characteristics of the engine is shown.

  15. Rockets: Educator's Guide with Activities in Science, Technology, Engineering and Mathematics

    Science.gov (United States)

    Shearer, Deborah A.; Vogt, Gregory L.

    2008-01-01

    This guide provides teachers and students many opportunities. Chapters within the guide present the history of rocketry, National Aeronautics and Space Administration's (NASA's) 21st Century Space Exploration Policy, rocketry principles, and practical rocketry. These topics lay the foundation for what follows--a wealth of dynamic rocket science…

  16. Hydrogen Fire Detection System Features Sharp Discrimination

    Science.gov (United States)

    Bright, C. S.

    1966-01-01

    Hydrogen fire detection system discovers fires by detecting the flickering ultraviolet radiation emitted by the OH molecule, a short-lived intermediate combustion product found in hydrogen-air flames. In a space application, the system discriminates against false signals from sunlight and rocket engine exhaust plume radiation.

  17. THE POSSIBILITY OF USING LASER-ULTRASOUND TO MONITOR THE QUALITY SOLDERED CONNECTIONS CHAMBERS OF LIQUID ROCKET ENGINES

    Directory of Open Access Journals (Sweden)

    N. V. Astredinova

    2014-01-01

    Full Text Available During the manufacturing process to the design of modern liquid rocket engines are presented important requirements, such as minimum weight, maximum stiffness and strength of nodes, maximum service life in operation, high reliability and quality of soldered and welded seams. Due to the high quality requirements soldered connections and the specific design of the nozzle, it became necessary in the development and testing of a new non-conventional non-destructive testing method – laser-ultrasound diagnosis. In accordance with regulatory guidelines, quality control soldered connections is allowed to use an acoustic kind of control methods of the reflected light, transmitted light, resonant, free vibration and acoustic emission. Attempts to use traditional methods of non-destructive testing did not lead to positive results. This is due primarily to the size of typical solder joint defects, as well as the structural features of the rocket engine, the data structure is not controllable. In connection with this, a new method that provides quality control soldered connections cameras LRE based on the thermo generation of ultrasound. Methods of ultrasonic flaw detection of photoacoustic effect, in most cases, have a number of advantages over methods that use standard (traditional piezo transducers. In the course of studies have found that the sensitivity of the laser-ultrasonic method and flaw detector UDL-2M can detect lack of adhesion in the solder joints on the upper edges of the nozzle in the sub-header area of the site.

  18. Fabrication of High Thermal Conductivity NARloy-Z-Diamond Composite Combustion Chamber Liner for Advanced Rocket Engines

    Science.gov (United States)

    Bhat, Biliyar N.; Greene, Sandra E.; Singh, Jogender

    2016-01-01

    NARloy-Z alloy (Cu-3 percent, Ag-0.5 percent, Zr) is a state of the art alloy currently used for fabricating rocket engine combustion chamber liners. Research conducted at NASA-MSFC and Penn State – Applied Research Laboratory has shown that thermal conductivity of NARloy-Z can be increased significantly by adding diamonds to form a composite (NARloy-Z-D). NARloy-Z-D is also lighter than NARloy-Z. These attributes make this advanced composite material an ideal candidate for fabricating combustion chamber liner for an advanced rocket engine. Increased thermal conductivity will directly translate into increased turbopump power and increased chamber pressure for improved thrust and specific impulse. This paper describes the process development for fabricating a subscale high thermal conductivity NARloy-Z-D combustion chamber liner using Field Assisted Sintering Technology (FAST). The FAST process uses a mixture of NARloy-Z and diamond powders which is sintered under pressure at elevated temperatures. Several challenges were encountered, i.e., segregation of diamonds, machining the super hard NARloy-Z-D composite, net shape fabrication and nondestructive examination. The paper describes how these challenges were addressed. Diamonds coated with copper (CuD) appear to give the best results. A near net shape subscale combustion chamber liner is being fabricated by diffusion bonding cylindrical rings of NARloy-Z-CuD using the FAST process.

  19. Concept of a self-pressurized feed system for liquid rocket engines and its fundamental experiment results

    Science.gov (United States)

    Matsumoto, Jun; Okaya, Shunichi; Igoh, Hiroshi; Kawaguchi, Junichiro

    2017-04-01

    A new propellant feed system referred to as a self-pressurized feed system is proposed for liquid rocket engines. The self-pressurized feed system is a type of gas-pressure feed system; however, the pressurization source is retained in the liquid state to reduce tank volume. The liquid pressurization source is heated and gasified using heat exchange from the hot propellant using a regenerative cooling strategy. The liquid pressurization source is raised to critical pressure by a pressure booster referred to as a charger in order to avoid boiling and improve the heat exchange efficiency. The charger is driven by a part of the generated pressurization gas using a closed-loop self-pressurized feed system. The purpose of this study is to propose a propellant feed system that is lighter and simpler than traditional gas pressure feed systems. The proposed system can be applied to all liquid rocket engines that use the regenerative cooling strategy. The concept and mathematical models of the self-pressurized feed system are presented first. Experiment results for verification are then shown and compared with the mathematical models.

  20. Aluminum/hydrocarbon gel propellants: An experimental and theoretical investigation of secondary atomization and predicted rocket engine performance

    Science.gov (United States)

    Mueller, Donn Christopher

    1997-12-01

    Experimental and theoretical investigations of aluminum/hydrocarbon gel propellant secondary atomization and its potential effects on rocket engine performance were conducted. In the experimental efforts, a dilute, polydisperse, gel droplet spray was injected into the postflame region of a burner and droplet size distributions was measured as a function of position above the burner using a laser-based sizing/velocimetry technique. The sizing/velocimetry technique was developed to measure droplets in the 10-125 mum size range and avoids size-biased detection through the use of a uniformly illuminated probe volume. The technique was used to determine particle size distributions and velocities at various axial locations above the burner for JP-10, and 50 and 60 wt% aluminum gels. Droplet shell formation models were applied to aluminum/hydrocarbon gels to examine particle size and mass loading effects on the minimum droplet diameter that will permit secondary atomization. This diameter was predicted to be 38.1 and 34.7 mum for the 50 and 60 wt% gels, which is somewhat greater than the experimentally measured 30 and 25 mum diameters. In the theoretical efforts, three models were developed and an existing rocket code was exercised to gain insights into secondary atomization. The first model was designed to predict gel droplet properties and shell stresses after rigid shell formation, while the second, a one-dimensional gel spray combustion model was created to quantify the secondary atomization process. Experimental and numerical comparisons verify that secondary atomization occurs in 10-125 mum diameter particles although an exact model could not be derived. The third model, a one-dimensional gel-fueled rocket combustion chamber, was developed to evaluate secondary atomization effects on various engine performance parameters. Results show that only modest secondary atomization may be required to reduce propellant burnout distance and radiation losses. A solid propellant

  1. Development of eddy current testing system for inspection of combustion chambers of liquid rocket engines.

    Science.gov (United States)

    He, D F; Zhang, Y Z; Shiwa, M; Moriya, S

    2013-01-01

    An eddy current testing (ECT) system using a high sensitive anisotropic magnetoresistive (AMR) sensor was developed. In this system, a 20 turn circular coil with a diameter of 3 mm was used to produce the excitation field. A high sensitivity AMR sensor was used to measure the magnetic field produced by the induced eddy currents. A specimen made of copper alloy was prepared to simulate the combustion chamber of liquid rocket. Scanning was realized by rotating the chamber with a motor. To reduce the influence of liftoff variance during scanning, a dual frequency excitation method was used. The experimental results proved that ECT system with an AMR sensor could be used to check liquid rocket combustion chamber.

  2. Modeling of Uneven Flow and Electromagnetic Field Parameters in the Combustion Chamber of Liquid Rocket Engine with a Near-wall Layer Available

    Directory of Open Access Journals (Sweden)

    A. V. Rudinskii

    2015-01-01

    Full Text Available The paper concerns modeling of an uneven flow and electromagnetic field parameters in the combustion chamber of the liquid rocket engine with a near-wall layer available.The research objective was to evaluate quantitatively influence of changing model chamber mode of the liquid rocket engine on the electro-physical characteristics of the hydrocarbon fuel combustion by-products.The main method of research was based on development of a final element model of the flowing path of the rocket engine chamber and its adaptation to the boundary conditions.The paper presents a developed two-dimensional non-stationary mathematical model of electro-physical processes in the liquid rocket engine chamber using hydrocarbon fuel. The model takes into consideration the features of a gas-dynamic contour of the engine chamber and property of thermo-gas-dynamic characteristics of the ionized products of combustion of hydrocarbonic fuel. Distributions of magnetic field intensity and electric conductivity received and analyzed taking into account a low-temperature near-wall layer. Special attention is paid to comparison of obtained calculation values of the electric current, which is taken out from intrachamber space of the engine with earlier published data of other authors.

  3. Research on shock wave characteristics in the isolator of central strut rocket-based combined cycle engine under Ma5.5

    Science.gov (United States)

    Wei, Xianggeng; Xue, Rui; Qin, Fei; Hu, Chunbo; He, Guoqiang

    2017-11-01

    A numerical calculation of shock wave characteristics in the isolator of central strut rocket-based combined cycle (RBCC) engine fueled by kerosene was carried out in this paper. A 3D numerical model was established by the DES method. The kerosene chemical kinetic model used the 9-component and 12-step simplified mechanism model. Effects of fuel equivalence ratio, inflow total temperature and central strut rocket on-off on shock wave characteristics were studied under Ma5.5. Results demonstrated that with the increase of equivalence ratio, the leading shock wave moves toward upstream, accompanied with higher possibility of the inlet unstart. However, the leading shock wave moves toward downstream as the inflow total temperature rises. After the central strut rocket is closed, the leading shock wave moves toward downstream, which can reduce risks of the inlet unstart. State of the shear layer formed by the strut rocket jet flow and inflow can influence the shock train structure significantly.

  4. Subscale Carbon-Carbon Nozzle Extension Development and Hot Fire Testing in Support of Upper Stage Liquid Rocket Engines

    Science.gov (United States)

    Gradl, Paul; Valentine, Peter; Crisanti, Matthew; Greene, Sandy Elam

    2016-01-01

    Upper stage and in-space liquid rocket engines are optimized for performance through the use of high area ratio nozzles to fully expand combustion gases to low exit pressures increasing exhaust velocities. Due to the large size of such nozzles and the related engine performance requirements, carbon-carbon (C/C) composite nozzle extensions are being considered for use in order to reduce weight impacts. NASA and industry partner Carbon-Carbon Advanced Technologies (C-CAT) are working towards advancing the technology readiness level of large-scale, domestically-fabricated, C/C nozzle extensions. These C/C extensions have the ability to reduce the overall costs of extensions relative to heritage metallic and composite extensions and to decrease weight by 50%. Material process and coating developments have advanced over the last several years, but hot fire testing to fully evaluate C/C nozzle extensions in relevant environments has been very limited. NASA and C-CAT have designed, fabricated and hot fire tested multiple subscale nozzle extension test articles of various C/C material systems, with the goal of assessing and advancing the manufacturability of these domestically producible materials as well as characterizing their performance when subjected to the typical environments found in a variety of liquid rocket and scramjet engines. Testing at the MSFC Test Stand 115 evaluated heritage and state-of-the-art C/C materials and coatings, demonstrating the capabilities of the high temperature materials and their fabrication methods. This paper discusses the design and fabrication of the 1.2k-lbf sized carbon-carbon nozzle extensions, provides an overview of the test campaign, presents results of the hot fire testing, and discusses potential follow-on development work.

  5. Models of Non-Stationary Thermodynamic Processes in Rocket Engines Taking into Account a Chemical Equilibrium of Combustion Products

    Directory of Open Access Journals (Sweden)

    A. V. Aliev

    2015-01-01

    Full Text Available The paper considers the two approach-based techniques for calculating the non-stationary intra-chamber processes in solid-propellant rocket engine (SPRE. The first approach assumes that the combustion products are a mechanical mix while the other one supposes it to be the mix, which is in chemical equilibrium. To enhance reliability of solution of the intra ballistic tasks, which assume a chemical equilibrium of combustion products, the computing algorithms to calculate a structure of the combustion products are changed. The algorithm for solving a system of the nonlinear equations of chemical equilibrium, when determining the iterative amendments, uses the orthogonal QR method instead of a method of Gauss. Besides, a possibility to apply genetic algorithms in a task about a structure of combustion products is considered.It is shown that in the tasks concerning the prediction of non-stationary intra ballistic characteristics in a solid propellant rocket engine, application of models of mechanical mix and chemically equilibrium structure of combustion products leads to qualitatively and quantitatively coinciding results. The maximum difference in parameters is 5-10%, at most. In tasks concerning the starting operation of a solid sustainer engine with high-temperature products of combustion difference in results is more essential, and can reach 20% and more.A technique to calculate the intra ballistic parameters, in which flotation of combustion products is considered in the light of a spatial statement, requires using the high-performance computer facilities. For these tasks it is offered to define structure of products of combustion and its thermo-physical characteristics, using the polynoms coefficients of which should be predefined.

  6. Carbon-Carbon Nozzle Extension Development in Support of In-Space and Upper-Stage Liquid Rocket Engines

    Science.gov (United States)

    Gradl, Paul R.; Valentine, Peter G.

    2017-01-01

    Upper stage and in-space liquid rocket engines are optimized for performance through the use of high area ratio nozzles to fully expand combustion gases to low exit pressures, increasing exhaust velocities. Due to the large size of such nozzles, and the related engine performance requirements, carbon-carbon (C-C) composite nozzle extensions are being considered to reduce weight impacts. Currently, the state-of-the-art is represented by the metallic and foreign composite nozzle extensions limited to approximately 2000 degrees F. used on the Atlas V, Delta IV, Falcon 9, and Ariane 5 launch vehicles. NASA and industry partners are working towards advancing the domestic supply chain for C-C composite nozzle extensions. These development efforts are primarily being conducted through the NASA Small Business Innovation Research (SBIR) program in addition to other low level internal research efforts. This has allowed for the initial material development and characterization, subscale hardware fabrication, and completion of hot-fire testing in relevant environments. NASA and industry partners have designed, fabricated and hot-fire tested several subscale domestically produced C-C extensions to advance the material and coatings fabrication technology for use with a variety of liquid rocket and scramjet engines. Testing at NASA's Marshall Space Flight Center (MSFC) evaluated heritage and state-of-the-art C-C materials and coatings, demonstrating the initial capabilities of the high temperature materials and their fabrication methods. This paper discusses the initial material development, design and fabrication of the subscale carbon-carbon nozzle extensions, provides an overview of the test campaign, presents results of the hot fire testing, and discusses potential follow-on development work. The follow on work includes the fabrication of ultra-high temperature materials, larger C-C nozzle extensions, material characterization, sub-element testing and hot-fire testing at

  7. Control Scheme Formulation for the Production of Hydrogen on Demand to Feed an Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Jarniel García Morales

    2016-12-01

    Full Text Available In this work, a control strategy is presented to produce hydrogen on demand to feed an internal combustion (IC engine. For this purpose, the modeling of the IC engine fueled by gasoline blended with 10 % v/v of anhydrous ethanol (E10 and hydrogen as an additive is developed. It is considered that the hydrogen gas is produced according to the IC engine demand, and that the hydrogen gas is obtained by an alkaline electrolyzer. The gasoline–ethanol blend added into the combustion chamber is determined according to the stoichiometric ratio and the production of hydrogen gas is regulated by a proportional and integral controller (P.I.. The controller reference is varying according to the mass flow air induced into the cylinder, in order to ensure an adequate production of hydrogen gas for any operating condition of the IC engine. The main contribution of this work is the control scheme developed, through simulation, in order to produce hydrogen on demand for any operating point of an internal combustion engine fueled by an E10 blend. The simulation results showed that the use of hydrogen gas as an additive in an E10 blend decreases the E10 fuel consumption 23 % on average, and the thermal efficiency is increased approximately 2.13 % , without brake power loss in the IC engine.

  8. Parametric Data from a Wind Tunnel Test on a Rocket-Based Combined-Cycle Engine Inlet

    Science.gov (United States)

    Fernandez, Rene; Trefny, Charles J.; Thomas, Scott R.; Bulman, Mel J.

    2001-01-01

    A 40-percent scale model of the inlet to a rocket-based combined-cycle (RBCC) engine was tested in the NASA Glenn Research Center 1- by 1-Foot Supersonic Wind Tunnel (SWT). The full-scale RBCC engine is scheduled for test in the Hypersonic Tunnel Facility (HTF) at NASA Glenn's Plum Brook Station at Mach 5 and 6. This engine will incorporate the configuration of this inlet model which achieved the best performance during the present experiment. The inlet test was conducted at Mach numbers of 4.0, 5.0, 5.5, and 6.0. The fixed-geometry inlet consists of an 8 deg.. forebody compression plate, boundary layer diverter, and two compressive struts located within 2 parallel sidewalls. These struts extend through the inlet, dividing the flowpath into three channels. Test parameters investigated included strut geometry, boundary layer ingestion, and Reynolds number (Re). Inlet axial pressure distributions and cross-sectional Pitot-pressure surveys at the base of the struts were measured at varying back-pressures. Inlet performance and starting data are presented. The inlet chosen for the RBCC engine self-started at all Mach numbers from 4 to 6. Pitot-pressure contours showed large flow nonuniformity on the body-side of the inlet. The inlet provided adequate pressure recovery and flow quality for the RBCC cycle even with the flow separation.

  9. Ground and Space-Based Measurement of Rocket Engine Burns in the Ionosphere

    Science.gov (United States)

    Bernhardt, P. A.; Ballenthin, J. O.; Baumgardner, J. L.; Bhatt, A.; Boyd, I. D.; Burt, J. M.; Caton, R. G.; Coster, A.; Erickson, P. J.; Huba, J. D.; hide

    2013-01-01

    On-orbit firings of both liquid and solid rocket motors provide localized disturbances to the plasma in the upper atmosphere. Large amounts of energy are deposited to ionosphere in the form of expanding exhaust vapors which change the composition and flow velocity. Charge exchange between the neutral exhaust molecules and the background ions (mainly O+) yields energetic ion beams. The rapidly moving pickup ions excite plasma instabilities and yield optical emissions after dissociative recombination with ambient electrons. Line-of-sight techniques for remote measurements rocket burn effects include direct observation of plume optical emissions with ground and satellite cameras, and plume scatter with UHF and higher frequency radars. Long range detection with HF radars is possible if the burns occur in the dense part of the ionosphere. The exhaust vapors initiate plasma turbulence in the ionosphere that can scatter HF radar waves launched from ground transmitters. Solid rocket motors provide particulates that become charged in the ionosphere and may excite dusty plasma instabilities. Hypersonic exhaust flow impacting the ionospheric plasma launches a low-frequency, electromagnetic pulse that is detectable using satellites with electric field booms. If the exhaust cloud itself passes over a satellite, in situ detectors measure increased ion-acoustic wave turbulence, enhanced neutral and plasma densities, elevated ion temperatures, and magnetic field perturbations. All of these techniques can be used for long range observations of plumes in the ionosphere. To demonstrate such long range measurements, several experiments were conducted by the Naval Research Laboratory including the Charged Aerosol Release Experiment, the Shuttle Ionospheric Modification with Pulsed Localized Exhaust experiments, and the Shuttle Exhaust Ionospheric Turbulence Experiments.

  10. Control-oriented modeling of combustion and flow processes in liquid propellant rocket engines

    Science.gov (United States)

    Bentsman, Joseph; Pearlstein, Arne J.; Wilcutts, Mark A.

    1990-01-01

    This paper presents a control-oriented model of the flow, reaction, and transport processes in liquid propellant rocket combustion chambers, based on the multicomponent conservation laws of gas dynamics. This model provides a framework for the inclusion of detailed chemical kinetic relations, viscous and other dissipative effects, a variety of actuators and sensors, as well as process and measurement disturbances. In addition to its potential usefulness to the designer in understanding the dynamical complexity of the system and the sources of model uncertainty, the model provides a rigorous basis for control system design. An appraisal of current and feasible actuators and sensors, and their mathematical representation are included.

  11. Final Technical Report: Hydrogen Energy in Engineering Education (H2E3)

    Energy Technology Data Exchange (ETDEWEB)

    Lehman, Peter A.; Cashman, Eileen; Lipman, Timothy; Engel, Richard A.

    2011-09-15

    Schatz Energy Research Center's Hydrogen Energy in Engineering Education curriculum development project delivered hydrogen energy and fuel cell learning experiences to over 1,000 undergraduate engineering students at five California universities, provided follow-on internships for students at a fuel cell company; and developed commercializable hydrogen teaching tools including a fuel cell test station and a fuel cell/electrolyzer experiment kit. Monitoring and evaluation tracked student learning and faculty and student opinions of the curriculum, showing that use of the curriculum did advance student comprehension of hydrogen fundamentals. The project web site (hydrogencurriculum.org) provides more information.

  12. The storage of hydrogen in the form of metal hydrides: An application to thermal engines

    Science.gov (United States)

    Gales, C.; Perroud, P.

    1981-01-01

    The possibility of using LaNi56, FeTiH2, or MgH2 as metal hydride storage sytems for hydrogen fueled automobile engines is discussed. Magnesium copper and magnesium nickel hydrides studies indicate that they provide more stable storage systems than pure magnesium hydrides. Several test engines employing hydrogen fuel have been developed: a single cylinder motor originally designed for use with air gasoline mixture; a four-cylinder engine modified to run on an air hydrogen mixture; and a gas turbine.

  13. Concept study of a hydrogen containment process during nuclear thermal engine ground testing

    Science.gov (United States)

    Wang, Ten-See; Stewart, Eric T.; Canabal, Francisco

    A new hydrogen containment process was proposed for ground testing of a nuclear thermal engine. It utilizes two thermophysical steps to contain the hydrogen exhaust. First, the decomposition of hydrogen through oxygen-rich combustion at higher temperature; second, the recombination of remaining hydrogen with radicals at low temperature. This is achieved with two unit operations: an oxygen-rich burner and a tubular heat exchanger. A computational fluid dynamics methodology was used to analyze the entire process on a three-dimensional domain. The computed flammability at the exit of the heat exchanger was less than the lower flammability limit, confirming the hydrogen containment capability of the proposed process.

  14. Design of Cooling Channels of Preburners for Small Liquid Rocket Engines with Computational Flow and Heat Transfer Analysis

    Directory of Open Access Journals (Sweden)

    Insang Moon

    2011-09-01

    Full Text Available A series of computational analyses was performed to predict the cooling process by the cooling channel of preburners used for kerosene-liquid oxygen staged combustion cycle rocket engines. As an oxygen-rich combustion occurs in the kerosene fueled preburner, it is of great importance to control the wall temperature so that it does not exceed the critical temperature. However, since the heat transfer is proportional to the speed of fluid running inside the channel, the high heat transfer leads to a trade-off of pressure loss. For this reason, it is necessary to establish a certain criteria between the pressure loss and the heat transfer or the wall surface temperature. The design factors of the cooling channel were determined by the computational research, and a test model was manufactured. The test model was used for the hot fire tests to prove the function of the cooling mechanism, among other purposes.

  15. The issue of ensuring the safe explosion of the spent orbital stages of a launch vehicle with propulsion rocket engine

    Directory of Open Access Journals (Sweden)

    Trushlyakov Valeriy I.

    2017-01-01

    Full Text Available A method for increasing the safe explosion of the spent orbital stages of a space launch vehicle (SLV with a propulsion rocket engine (PRE based on the gasification of unusable residues propellant and venting fuel tanks. For gasification and ventilation the hot gases used produced by combustion of the specially selected gas generating composition (GGC with a set of physical and chemical properties. Excluding the freezing of the drainage system on reset gasified products (residues propellant+pressurization gas+hot gases in the near-Earth space is achieved by selecting the physical-chemical characteristics of the GGC. Proposed steps to ensure rotation of gasified products due to dumping through the drainage system to ensure the most favorable conditions for propellant gasification residues. For example, a tank with liquid oxygen stays with the orbital spent second stage of the SLV “Zenit”, which shows the effectiveness of the proposed method.

  16. Computational Modelling of the Preflow Phase during Start-Up of AN Upper-Stage Rocket Engine

    Science.gov (United States)

    Steelant, J.; Schmehl, R.

    2005-02-01

    A computational analysis of the oxidiser preflow during start-up of a storable propellant upper-stage rocket engine is presented. To account for flash-evaporation of the superheated liquid oxidiser new physical models and numerical solution techniques are developed and implemented into the framework of an iterative Euler-Lagrange method. The computed three-dimensional two-phase flow field and spray deposit distribution in combustion chamber and nozzle extension is analysed. The influence of liquid injection temperature, initial droplet sizes and wall temperature on the preflow is assessed by detailed parametric studies. Validated by experimental data, the results are used to derive transfer functions describing the preflow dynamics on a system level.

  17. Hydrogen enriched compressed natural gas (HCNG: A futuristic fuel for internal combustion engines

    Directory of Open Access Journals (Sweden)

    Nanthagopal Kasianantham

    2011-01-01

    Full Text Available Air pollution is fast becoming a serious global problem with increasing population and its subsequent demands. This has resulted in increased usage of hydrogen as fuel for internal combustion engines. Hydrogen resources are vast and it is considered as one of the most promising fuel for automotive sector. As the required hydrogen infrastructure and refueling stations are not meeting the demand, widespread introduction of hydrogen vehicles is not possible in the near future. One of the solutions for this hurdle is to blend hydrogen with methane. Such types of blends take benefit of the unique combustion properties of hydrogen and at the same time reduce the demand for pure hydrogen. Enriching natural gas with hydrogen could be a potential alternative to common hydrocarbon fuels for internal combustion engine applications. Many researchers are working on this for the last few years and work is now focused on how to use this kind of fuel to its maximum extent. This technical note is an assessment of HCNG usage in case of internal combustion engines. Several examples and their salient features have been discussed. Finally, overall effects of hydrogen addition on an engine fueled with HCNG under various conditions are illustrated. In addition, the scope and challenges being faced in this area of research are clearly described.

  18. A methodology to study the possible occurrence of chugging in liquid rocket engines during transient start-up

    Science.gov (United States)

    Leonardi, Marco; Nasuti, Francesco; Di Matteo, Francesco; Steelant, Johan

    2017-10-01

    An investigation on the low frequency combustion instabilities due to the interaction of combustion chamber and feed line dynamics in a liquid rocket engine is carried out implementing a specific module in the system analysis software EcosimPro. The properties of the selected double time lag model are identified according to the two classical assumptions of constant and variable time lag. Module capabilities are evaluated on a literature experimental set up consisting of a combustion chamber decoupled from the upstream feed lines. The computed stability map results to be in good agreement with both experimental data and analytical models. Moreover, the first characteristic frequency of the engine is correctly predicted, giving confidence on the use of the module for the analysis of chugging instabilities. As an example of application, a study is carried out on the influence of the feed lines on the system stability, correctly capturing that the lines extend the stable regime of the combustion chamber and that the propellant domes play a key role in coupling the dynamics of combustion chamber and feed lines. A further example is presented to discuss on the role of pressure growth rate and of the combustion chamber properties on the possible occurrence of chug instability during engine start-up and on the conditions that lead to its damping or growth.

  19. The main indicators of the health of children and adolescents in residential zone of the facility for disposal of rocket engines

    Directory of Open Access Journals (Sweden)

    Tarakanova S.Y.

    2014-12-01

    39.5%. The main cause of morbidity in children is diseases of the nervous system and mental disorders, and congenital anomalies. Conclusion. Operation of installations for the disposal of rocket engines solid fuel according to the official reporting forms medical institutions has no effect on child health.

  20. The Influence of Hydrogen Gas on the Measures of Efficiency of Diesel Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Jurgis Latakas

    2014-12-01

    Full Text Available In this research paper energy and ecological parameters of diesel engine which works under addition of hydrogen (10, 20, 30 l/ min are presented. A survey of research literature has shown that addition of hydrogen gases improve diesel combustion; increase indicated pressure; decrease concentration of carbon dioxide (CO2, hydrocarbons (HC, particles; decrease fuel consumptions. Results of the experiment revealed that hydrogen gas additive decreased pressure in cylinder in kinetic combustion phase. Concentration of CO2 and nitrous oxides (NOx decreased not significantly, HC – increased. Concentration of particles in engine exhaust gases significantly decreased. In case when hydrogen gas as additive was supplied, the fuel consumptions decreased a little. Using AVL BOOST software combustion process analysis was made. It was determined that in order to optimize engine work process under hydrogen additive usage, it is necessary to adjust diesel injection angle.

  1. Start up system for hydrogen generator used with an internal combustion engine

    Science.gov (United States)

    Houseman, J.; Cerini, D. J. (Inventor)

    1977-01-01

    A hydrogen generator provides hydrogen rich product gases which are mixed with the fuel being supplied to an internal combustion engine for the purpose of enabling a very lean mixture of that fuel to be used, whereby nitrous oxides emitted by the engine are minimized. The hydrogen generator contains a catalyst which must be heated to a pre-determined temperature before it can react properly. To simplify the process of heating up the catalyst at start-up time, either some of the energy produced by the engine such as engine exhaust gas, or electrical energy produced by the engine, or the engine exhaust gas may be used to heat up air which is then used to heat the catalyst.

  2. Coil-On-Plug Ignition for Oxygen/Methane Liquid Rocket Engines in Thermal-Vacuum Environments

    Science.gov (United States)

    Melcher, John C.; Atwell, Matthew J.; Morehead, Robert L.; Hurlbert, Eric A.; Bugarin, Luz; Chaidez, Mariana

    2017-01-01

    A coil-on-plug ignition system has been developed and tested for Liquid Oxygen (LOX)/liquid methane (LCH4) rocket engines operating in thermal vacuum conditions. The igniters were developed and tested as part of the Integrated Cryogenic Propulsion Test Article (ICPTA), previously tested as part of the Project Morpheus test vehicle. The ICPTA uses an integrated, pressure-fed, cryogenic LOX/LCH4 propulsion system including a reaction control system (RCS) and a main engine. The ICPTA was tested at NASA Glenn Research Center's Plum Brook Station in the Spacecraft Propulsion Research Facility (B-2) under vacuum and thermal vacuum conditions. A coil-on-plug ignition system has been developed to successfully demonstrate ignition reliability at these conditions while preventing corona discharge issues. The ICPTA uses spark plug ignition for both the main engine igniter and the RCS. The coil-on-plug configuration eliminates the conventional high-voltage spark plug cable by combining the coil and the spark plug into a single component. Prior to ICPTA testing at Plum Brook, component-level reaction control engine (RCE) and main engine igniter testing was conducted at NASA Johnson Space Center (JSC), which demonstrated successful hot-fire ignition using the coil-on-plug from sea-level ambient conditions down to 10(exp -2) torr. Integrated vehicle hot-fire testing at JSC demonstrated electrical and command/data system performance. Lastly, hot-fire testing at Plum Brook demonstrated successful ignitions at simulated altitude conditions at 30 torr and cold thermal-vacuum conditions at 6 torr. The test campaign successfully proved that coil-on-plug technology will enable integrated LOX/LCH4 propulsion systems in future spacecraft.

  3. Orbit transfer rocket engine technology program: Automated preflight methods concept definition

    Science.gov (United States)

    Erickson, C. M.; Hertzberg, D. W.

    1991-12-01

    The possibility of automating preflight engine checkouts on orbit transfer engines is discussed. The minimum requirements in terms of information and processing necessary to assess the engine'e integrity and readiness to perform its mission were first defined. A variety of ways for remotely obtaining that information were generated. The sophistication of these approaches varied from a simple preliminary power up, where the engine is fired up for the first time, to the most advanced approach where the sensor and operational history data system alone indicates engine integrity. The critical issues and benefits of these methods were identified, outlined, and prioritized. The technology readiness of each of these automated preflight methods were then rated on a NASA Office of Exploration scale used for comparing technology options for future mission choices. Finally, estimates were made of the remaining cost to advance the technology for each method to a level where the system validation models have been demonstrated in a simulated environment.

  4. Modelling of flame propagation in the gasoline fuelled Wankel rotary engine with hydrogen additives

    Science.gov (United States)

    Fedyanov, E. A.; Zakharov, E. A.; Prikhodkov, K. V.; Levin, Y. V.

    2017-02-01

    Recently, hydrogen has been considered as an alternative fuel for a vehicles power unit. The Wankel engine is the most suitable to be adapted to hydrogen feeding. A hydrogen additive helps to decrease incompleteness of combustion in the volumes near the apex of the rotor. Results of theoretical researches of the hydrogen additives influence on the flame propagation in the combustion chamber of the Wankel rotary engine are presented. The theoretical research shows that the blend of 70% gasoline with 30% hydrogen could accomplish combustion near the T-apex in the stoichiometric mixture and in lean one. Maps of the flame front location versus the angle of rotor rotation and hydrogen fraction are obtained. Relations of a minimum required amount of hydrogen addition versus the engine speed are shown on the engine modes close to the average city driving cycle. The amount of hydrogen addition that could be injected by the nozzle with different flow sections is calculated in order to analyze the capacity of the feed system.

  5. Non-traditional Process of Hydrogen Containing Fuel Mixtures Production for Internal-combustion Engines

    Directory of Open Access Journals (Sweden)

    Gennady G. Kuvshinov

    2012-12-01

    Full Text Available The article justifies the perspectives of development of the environmentally sound technology of hydrogen containing fuel mixtures for internal-combustion engines based on the catalytic process of low-temperature decomposition of hydrocarbons into hydrogen and nanofibrous carbon.

  6. Heat transfer comparison between methane and hydrogen in a spark ignited engine

    Energy Technology Data Exchange (ETDEWEB)

    Sierens, Roger; Demuynck, Joachim; Paepe, Michel de; Verhelst, Sebastian [Ghent Univ. (Belgium)

    2010-07-01

    Hydrogen is one of the alternative fuels which are being investigated at Ghent University. NO{sub x} emissions will occur at high engine loads and they are a constraint for power and efficiency optimization. The formation of NO{sub x} emissions is temperature dependent. Consequently, the heat transfer from the burning gases to the cylinder walls has to be accurately modelled if precise computer calculations of the emissions are wanted. Several engine heat transfer models exist but they have been cited to be inaccurate for hydrogen. We have measured the heat flux in a spark ignited engine with a commercially available heat flux sensor. This paper investigates the difference between the heat transfer of hydrogen and a fossil fuel, in this case methane. Measurements with the same indicated power output are compared and the effect of the heat loss on the indicated efficiency is investigated. The power output of hydrogen combustion is lowered by burning lean in contrast to using a throttle in the case of methane. Although the peak in the heat flux of hydrogen is 3 times higher compared to methane for a high engine power output, the indicated efficiency is only 3% lower. The heat loss for hydrogen at a low engine load is smaller than that of methane which results in a higher indicated efficiency. The richness of the hydrogen-air mixture has a great influence on the heat transfer process in contrast to the in-cylinder mass in the case of methane. (orig.)

  7. Relation of Hydrogen and Methane to Carbon Monoxide in Exhaust Gases from Internal-Combustion Engines

    Science.gov (United States)

    Gerrish, Harold C; Tessmann, Arthur M

    1935-01-01

    The relation of hydrogen and methane to carbon monoxide in the exhaust gases from internal-combustion engines operating on standard-grade aviation gasoline, fighting-grade aviation gasoline, hydrogenated safety fuel, laboratory diesel fuel, and auto diesel fuel was determined by analysis of the exhaust gases. Two liquid-cooled single-cylinder spark-ignition, one 9-cylinder radial air-cooled spark-ignition, and two liquid-cooled single-cylinder compression-ignition engines were used.

  8. 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.

  9. Ford/BASF/UM Activities in Support of the Hydrogen Storage Engineering Center of Excellence

    Energy Technology Data Exchange (ETDEWEB)

    Veenstra, Mike [Ford Motor Company, Dearborn, MI (United States); Purewal, Justin [Ford Motor Company, Dearborn, MI (United States); Xu, Chunchuan [Ford Motor Company, Dearborn, MI (United States); Yang, Jun [Ford Motor Company, Dearborn, MI (United States); Blaser, Rachel [Ford Motor Company, Dearborn, MI (United States); Sudik, Andrea [Ford Motor Company, Dearborn, MI (United States); Siegel, Don [Univ. of Michigan, Ann Arbor, MI (United States); Ming, Yang [Univ. of Michigan, Ann Arbor, MI (United States); Liu, Dong' an [Univ. of Michigan, Ann Arbor, MI (United States); Chi, Hang [Univ. of Michigan, Ann Arbor, MI (United States); Gaab, Manuela [BASF SE, Ludwigshafen (Germany); Arnold, Lena [BASF SE, Ludwigshafen (Germany); Muller, Ulrich [BASF SE, Ludwigshafen (Germany)

    2015-06-30

    Widespread adoption of hydrogen as a vehicular fuel depends critically on the development of low-cost, on-board hydrogen storage technologies capable of achieving high energy densities and fast kinetics for hydrogen uptake and release. As present-day technologies -- which rely on physical storage methods such as compressed hydrogen -- are incapable of attaining established Department of Energy (DOE) targets, development of materials-based approaches for storing hydrogen have garnered increasing attention. Material-based storage technologies have potential to store hydrogen beyond twice the density of liquid hydrogen. To hasten development of these ‘hydride’ materials, the DOE previously established three centers of excellence for materials storage R&D associated with the key classes of materials: metal hydrides, chemical hydrogen, and adsorbents. While these centers made progress in identifying new storage materials, the challenges associated with the engineering of the system around a candidate storage material are in need of further advancement. In 2009 the DOE established the Hydrogen Storage Engineering Center of Excellence with the objective of developing innovative engineering concepts for materials-based hydrogen storage systems. As a partner in the Hydrogen Storage Engineering Center of Excellence, the Ford-UM-BASF team conducted a multi-faceted research program that addresses key engineering challenges associated with the development of materials-based hydrogen storage systems. First, we developed a novel framework that allowed for a material-based hydrogen storage system to be modeled and operated within a virtual fuel cell vehicle. This effort resulted in the ability to assess dynamic operating parameters and interactions between the storage system and fuel cell power plant, including the evaluation of performance throughout various drive cycles. Second, we engaged in cost modeling of various incarnations of the storage systems. This analysis

  10. Biochemical and genetic engineering strategies to enhance hydrogen production in photosynthetic algae and cyanobacteria.

    Science.gov (United States)

    Srirangan, Kajan; Pyne, Michael E; Perry Chou, C

    2011-09-01

    As an energy carrier, hydrogen gas is a promising substitute to carbonaceous fuels owing to its superb conversion efficiency, non-polluting nature, and high energy content. At present, hydrogen is predominately synthesized via chemical reformation of fossil fuels. While various biological methods have been extensively explored, none of them is justified as economically feasible. A sustainable platform for biological production of hydrogen will certainly impact the biofuel market. Among a selection of biological systems, algae and cyanobacteria have garnered major interests as potential cell factories for hydrogen production. In conjunction with photosynthesis, these organisms utilize inexpensive inorganic substrates and solar energy for simultaneous biosynthesis and hydrogen evolution. However, the hydrogen yield associated with these organisms remains far too low to compete with the existing chemical systems. This article reviews recent advances of biochemical, bioprocess, and genetic engineering strategies in circumventing technological limitations to hopefully improve the applicative potential of these photosynthetic hydrogen production systems. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Thermal Hydraulics Design and Analysis Methodology for a Solid-Core Nuclear Thermal Rocket Engine Thrust Chamber

    Science.gov (United States)

    Wang, Ten-See; Canabal, Francisco; Chen, Yen-Sen; Cheng, Gary; Ito, Yasushi

    2013-01-01

    Nuclear thermal propulsion is a leading candidate for in-space propulsion for human Mars missions. This chapter describes a thermal hydraulics design and analysis methodology developed at the NASA Marshall Space Flight Center, in support of the nuclear thermal propulsion development effort. The objective of this campaign is to bridge the design methods in the Rover/NERVA era, with a modern computational fluid dynamics and heat transfer methodology, to predict thermal, fluid, and hydrogen environments of a hypothetical solid-core, nuclear thermal engine the Small Engine, designed in the 1960s. The computational methodology is based on an unstructured-grid, pressure-based, all speeds, chemically reacting, computational fluid dynamics and heat transfer platform, while formulations of flow and heat transfer through porous and solid media were implemented to describe those of hydrogen flow channels inside the solid24 core. Design analyses of a single flow element and the entire solid-core thrust chamber of the Small Engine were performed and the results are presented herein

  12. Fire Protection Engineering Design Brief Template. Hydrogen Refueling Station.

    Energy Technology Data Exchange (ETDEWEB)

    LaFleur, Angela Christine [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Muna, Alice Baca [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Groth, Katrina M. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-08-01

    Building a hydrogen infrastructure system is critical to supporting the development of alternate- fuel vehicles. This report provides a methodology for implementing a performance-based design of an outdoor hydrogen refueling station that does not meet specific prescriptive requirements in NFPA 2, The Hydrogen Technologies Code . Performance-based designs are a code-compliant alternative to meeting prescriptive requirements. Compliance is demonstrated by comparing a prescriptive-based fueling station design with a performance-based design approach using Quantitative Risk Assessment (QRA) methods and hydrogen risk assessment tools. This template utilizes the Sandia-developed QRA tool, Hydrogen Risk Analysis Models (HyRAM), which combines reduced-order deterministic models that characterize hydrogen release and flame behavior with probabilistic risk models to quantify risk values. Each project is unique and this template is not intended to account for site-specific characteristics. Instead, example content and a methodology are provided for a representative hydrogen refueling site which can be built upon for new hydrogen applications.

  13. HYDROGEN ADDITION ON COMBUSTION AND EMISSION CHARACTERISTICS OF HIGH SPEED SPARK IGNITION ENGINE- AN EXPERIMENTAL STUDY

    Directory of Open Access Journals (Sweden)

    SHIVAPRASAD K. V.

    2016-11-01

    Full Text Available The present article aims at characterizing the combustion and emission parameters of a single cylinder high speed SI engine operating with different concentrations of hydrogen with gasoline fuel. The conventional carburetted SI engine was modified into an electronically controllable engine, wherein ECU was used to control the injection timings and durations of gasoline. The engine was maintained at a constant speed of 3000 rpm and wide open throttle position. The experimental results demonstrated that heat release rate and cylinder pressure were increased with the addition of hydrogen until 20%. The CO and HC emissions were reduced considerably whereas NOx emission was increased with the addition of hydrogen in comparison with pure gasoline engine operation.

  14. Study on the Effect of water Injection Momentum on the Cooling Effect of Rocket Engine Exhaust Plume

    Science.gov (United States)

    Yang, Kan; Qiang, Yanhui; Zhong, Chenghang; Yu, Shaozhen

    2017-10-01

    For the study of water injection momentum factors impact on flow field of the rocket engine tail flame, the numerical computation model of gas-liquid two phase flow in the coupling of high temperature and high speed gas flow and low temperature liquid water is established. The accuracy and reliability of the numerical model are verified by experiments. Based on the numerical model, the relationship between the flow rate and the cooling effect is analyzed by changing the water injection momentum of the water spray pipes. And the effective mathematical expression is obtained. What’s more, by changing the number of the water spray and using small flow water injection, the cooling effect is analyzed to check the application range of the mathematical expressions. The results show that: the impact and erosion of the gas flow field could be reduced greatly by water injection, and there are two parts in the gas flow field, which are the slow cooling area and the fast cooling area. In the fast cooling area, the influence of the water flow momentum and nozzle quantity on the cooling effect can be expressed by mathematical functions without causing bifurcation flow for the mainstream gas. The conclusion provides a theoretical reference for the engineering application.

  15. Theoretical and experimental analysis of liquid layer instability in hybrid rocket engines

    Science.gov (United States)

    Kobald, Mario; Verri, Isabella; Schlechtriem, Stefan

    2015-03-01

    The combustion behavior of different hybrid rocket fuels has been analyzed in the frame of this research. Tests have been performed in a 2D slab burner configuration with windows on two sides. Four different liquefying paraffin-based fuels, hydroxyl terminated polybutadiene (HTPB) and high-density polyethylene (HDPE) have been tested in combination with gaseous oxygen (GOX). Experimental high-speed video data have been analyzed manually and with the proper orthogonal decomposition (POD) technique. Application of POD enables the recognition of the main structures of the flow field and the combustion flame appearing in the video data. These results include spatial and temporal analysis of the structures. For liquefying fuels these spatial values relate to the wavelengths associated to the Kelvin Helmholtz Instability (KHI). A theoretical long-wave solution of the KHI problem shows good agreement with the experimental results. Distinct frequencies found in the POD analysis can be related to the precombustion chamber configuration which can lead to vortex shedding phenomena.

  16. A Framework for Assessing the Reusability of Hardware (Reusable Rocket Engines)

    Science.gov (United States)

    Childress-Thompson, Rhonda; Thomas, Dale; Farrington, Philip

    2016-01-01

    Within the past few years, there has been a renewed interest in reusability as it applies to space flight hardware. Commercial companies such as Space Exploration Technologies Corporation (SpaceX), Blue Origin, and United Launch Alliance (ULA) are pursuing reusable hardware. Even foreign companies are pursuing this option. The Indian Space Research Organization (ISRO) launched a reusable space plane technology demonstrator and Airbus Defense and Space is planning to recover the main engines and avionics from its Advanced Expendable Launcher with Innovative engine Economy [1] [2]. To date, the Space Shuttle remains as the only Reusable Launch (RLV) to have flown repeated missions and the Space Shutte Main Engine (SSME) is the only demonstrated reusable engine. Whether the hardware being considered for reuse is a launch vehicle (fully reusable), a first stage (partially reusable), or a booster engine (single component), the overall governing process is the same; it must be recovered and recertified for flight. Therefore, there is a need to identify the key factors in determining the reusability of flight hardware. This paper begins with defining reusability to set the context, addresses the significance of reuse, and discusses areas that limit successful implementation. Finally, this research identifies the factors that should be considered when incorporating reuse.

  17. Conversion of a commercial spark ignition engine to run on hydrogen: Performance comparison using hydrogen and gasoline

    Energy Technology Data Exchange (ETDEWEB)

    Sopena, C.; Dieguez, P.M.; Sainz, D.; Urroz, J.C.; Gandia, L.M. [Escuela Tecnica Superior de Ingenieros Industriales y de Telecomunicacion, Universidad Publica de Navarra, Campus de Arrosadia, E-31006 Pamplona (Spain); Guelbenzu, E. [Acciona Biocombustibles S.A., Avenida Ciudad de la Innovacion n 5, E-31621 Sarriguren, Navarra (Spain)

    2010-02-15

    The modifications performed to convert the spark ignition gasoline-fueled internal combustion engine of a Volkswagen Polo 1.4 to run with hydrogen are described. The car is representative of small vehicles widely used for both city and interurban traffic. Main changes included the inlet manifold, gas injectors, oil radiator and the electronic management unit. Injection and ignition advance timing maps were developed for lean mixtures with values of the air to hydrogen equivalence ratio ({lambda}) between 1.6 and 3. The established engine control parameters allowed the safe operation of the hydrogen-fueled engine (H{sub 2}ICE) free of knock, backfire and pre-ignition as well with reasonably low NO{sub x} emissions. The H{sub 2}ICE reached best brake torque of 63 Nm at 3800 rpm and maximum brake power of 32 kW at 5000 rpm. In general, the brake thermal efficiency of the H{sub 2}ICE is greater than that of gasoline-fueled engine except for the H{sub 2}ICE working at very lean conditions ({lambda} = 2.5) and high speeds (above 4000 rpm). A significant effect of the spark advance on the NO{sub x} emissions has been found, specially for relatively rich mixtures ({lambda} < 2). Small changes of spark advance with respect to the optimum value for maximum brake torque give rise to an increase of pollutant emissions. It has been estimated that the hydrogen-fueled Volkswagen Polo could reach a maximum speed of 140 km/h with the adapted engine. Moreover, there is enough reserve of power for the vehicle moving on typical urban routes and routes with slopes up to 10%. (author)

  18. CHOOSING OF PERFORMANCE PARAMETERS OF LIGHT-DUTY ENGINE RUNNING ON NATURAL GAS AND HYDROGEN MIXTURE

    Directory of Open Access Journals (Sweden)

    Y. Dube

    2011-01-01

    Full Text Available The results of investigation of light-duty gas engine running on natural gas and hydrogen mixture has been given. The mathematical model of combustion process with variable Vibe combus-tion factor for this engine type has been specified.

  19. Up the Technology Readiness Level (TRL) Scale to Demonstrate a Robust, Long Life, Liquid Rocket Engine Combustion Chamber, or...Up the Downstairs

    Science.gov (United States)

    Holmes, Richard; Elam, Sandra; McKechnie, Timothy; Power, Christopher

    2008-01-01

    Advanced vacuum plasma spray (VPS) technology, utilized to successfully apply thermal barrier coatings to space shuttle main engine turbine blades, was further refined as a functional gradient material (FGM) process for space furnace cartridge experiments at 1600 C and for robust, long life combustion chambers for liquid rocket engines. A VPS/FGM 5K (5,000 lb. thrust) thruster has undergone 220 hot firing tests, in pristine condition, showing no wear, blanching or cooling channel cracks. Most recently, this technology has been applied to a 40K thruster, with scale up planned for a 194K Ares I, J-2X engine.

  20. Simulations of Multi Combustion Modes Hydrogen Engines for Heavy Duty Trucks

    Directory of Open Access Journals (Sweden)

    Alberto A. Boretti

    2012-01-01

    Full Text Available The paper presents the numerical study of a diesel direct injection heavy duty truck engine converted to hydrogen. The engine has a power turbine connected through a clutch and a continuously variable transmission to the crankshaft. The power turbine may be disconnected and by-passed when it is inefficient or inconvenient to use. The conversion is obtained by replacing the Diesel injector with a hydrogen injector and the glow plug with a jet ignition device. The hydrogen engine operates different modes of combustion depending on the relative phasing of the main injection and the jet ignition. The engine generally operates mostly in Diesel-like mode, with the most part of the main injection following the suitable creation in cylinder conditions by jet ignition. For medium-low loads, better efficienciy is obtained with the gasoline-like mode jet igniting the premixed homogeneous mixture at top dead centre. It’s permitted at higher loads or at very low loads for the excessive peak pressure or the mixture too lean to burn rapidly. The hydrogen engine has better efficiency than Diesel outputs and fuel conversion. Thanks to the larger rate of heat release, it has the opportunity to run closer to stoichiometry and the multi mode capabilities. The critical area for this engine development is found in the design of a hydrogen injector delivering the amount of fuel needed to the large volume cylinder within a Diesel-like injection time.

  1. Numerical investigation of high-pressure combustion in rocket engines using Flamelet/Progress-variable models

    CERN Document Server

    Coclite, A; De Palma, P; Pascazio, G

    2015-01-01

    The present paper deals with the numerical study of high pressure LOx/H2 or LOx/hydrocarbon combustion for propulsion systems. The present research effort is driven by the continued interest in achieving low cost, reliable access to space and more recently, by the renewed interest in hypersonic transportation systems capable of reducing time-to-destination. Moreover, combustion at high pressure has been assumed as a key issue to achieve better propulsive performance and lower environmental impact, as long as the replacement of hydrogen with a hydrocarbon, to reduce the costs related to ground operations and increase flexibility. The current work provides a model for the numerical simulation of high- pressure turbulent combustion employing detailed chemistry description, embedded in a RANS equations solver with a Low Reynolds number k-omega turbulence model. The model used to study such a combustion phenomenon is an extension of the standard flamelet-progress-variable (FPV) turbulent combustion model combined ...

  2. Concept for lowest emissions of a hydrogen internal combustion engine; Niedrigstemissionskonzept fuer einen wasserstoffbetriebenen Verbrennungsmotor

    Energy Technology Data Exchange (ETDEWEB)

    Fouquet, Marcel Christian Thomas

    2012-03-15

    This paper describes a concept with lowest emissions for a hydrogen internal combustion engine for passenger cars. With optimisation of the combustion concept the level of nitrogen oxide is below 90%, hydrocarbon and carbon monoxide below 99% of the SULEV target (CARB). This concept enables a potential in power density that is comparable to current supercharged combustion engines at lowest emission level without catalytic aftertreatment. Additionally with a catalytic aftertreatment system, the emission level of a current hydrogen combustion engine (mono-fuel) is lowered to a level, that this car can be labeled as air cleaning vehicle for hydrocarbons and carbon monoxide.

  3. Electric field and radio frequency measurements for rocket engine health monitoring applications

    Science.gov (United States)

    Valenti, Elizabeth L.

    1992-01-01

    Electric-field (EF) and radio-frequency (RF) emissions generated in the exhaust plumes of the diagnostic testbed facility thruster (DTFT) and the SSME are examined briefly for potential applications to plume diagnostics and engine health monitoring. Hypothetically, anomalous engine conditions could produce measurable changes in any characteristic EF and RF spectral signatures identifiable with a 'healthly' plumes. Tests to determine the presence of EF and RF emissions in the DTFT and SSME exhaust plumes were conducted. EF and RF emissions were detected using state-of-the-art sensors. Analysis of limited data sets show some apparent consistencies in spectral signatures. Significant emissions increases were detected during controlled tests using dopants injected into the DTFT.

  4. Microthruster Fabrication and Characterization: In Search of the Optimal Nozzle Geometry for Microscale Rocket Engines

    OpenAIRE

    Fowee, Katherine L; Alexeenko, Alina

    2014-01-01

    A major consideration in microsatellite design is the engineering of micropropulsion systems that can deliver the required thrust efficiently with tight restrictions on space, weight, and power. Cold gas thrusters are one solution to the demand for smaller propulsion systems to accommodate the advancements in technology that have allowed for a reduction in the size and thus the cost of satellites. While much research has been done in understanding the flow regimes within these microthrusters,...

  5. Development and Testing of Carbon-Carbon Nozzle Extensions for Upper Stage Liquid Rocket Engines

    Science.gov (United States)

    Valentine, Peter G.; Gradl, Paul R.; Greene, Sandra E.

    2017-01-01

    Carbon-carbon (C-C) composite nozzle extensions are of interest for use on a variety of launch vehicle upper stage engines and in-space propulsion systems. The C-C nozzle extension technology and test capabilities being developed are intended to support National Aeronautics and Space Administration (NASA) and Department of Defense (DOD) requirements, as well as those of the broader Commercial Space industry. For NASA, C-C nozzle extension technology development primarily supports the NASA Space Launch System (SLS) and NASA's Commercial Space partners. Marshall Space Flight Center (MSFC) efforts are aimed at both (a) further developing the technology and databases needed to enable the use of composite nozzle extensions on cryogenic upper stage engines, and (b) developing and demonstrating low-cost capabilities for testing and qualifying composite nozzle extensions. Recent, on-going, and potential future work supporting NASA, DOD, and Commercial Space needs will be discussed. Information to be presented will include (a) recent and on-going mechanical, thermal, and hot-fire testing, as well as (b) potential future efforts to further develop and qualify domestic C-C nozzle extension solutions for the various upper stage engines under development.

  6. Hydrogen SI and HCCI Combustion in a Direct-Injection Optical Engine

    OpenAIRE

    Rosati, MF; Aleiferis, PG

    2009-01-01

    Hydrogen has been largely proposed as a possible alternative fuel for internal combustion engines. Its wide flammability range allows higher engine efficiency with leaner operation than conventional fuels, for both reduced toxic emissions and no CO2 gases. Independently, Homogenous Charge Compression Ignition (HCCI) also allows higher thermal efficiency and lower fuel consumption with reduced NOX emissions when compared to Spark-Ignition (SI) engine operation. For HCCI combustion, a mixture o...

  7. Combustion stability analysis of preburners in liquid propellant rocket engines during shutdown

    Science.gov (United States)

    Lim, Kair-Chuan; George, Paul E., II

    1987-01-01

    A linearized one-dimensional lumped-parameter model capable of predicting the occurrence of the low frequency combustion instability (chugging) experienced during preburner shutdown in the Space Shuttle Main Engines is discussed, and predictions are compared with NASA experimental results. Results from a parametric study of parameters including chamber pressure, fuel and oxygen temperatures, and the effective bulk modulus of the liquid oxidizer suggest that chugging is probably affected by conditions at shutdown through the fuel and oxidizer temperatures. It is suggested that chugging is initiated when the fuel, oxidizer, and helium temperature and flow rates pass into an unstable region, and that chugging may be terminated by decaying pressures.

  8. Conceptual design for a kerosene fuel-rich gas-generator of a turbopump-fed liquid rocket engine

    Science.gov (United States)

    Son, Min; Koo, Jaye; Cho, Won Kook; Lee, Eun Seok

    2012-10-01

    A design method for a kerosene fuel-rich gas-generator of a liquid rocket engine using turbopumps to supply propellant was performed at a conceptual level. The gas-generator creates hot gases, enabling the turbine to operate the turbopumps. A chemical non-equilibrium analysis and a droplet vaporization model were used for the estimation of the burnt gas properties and characteristic chamber length. A premixed counter-flow flame analysis was performed for the prediction of the burnt gas properties, namely the temperature, the specific heat ratio and heat capacity, and the chemical reaction time. To predict the vaporization time, the Spalding model, using a single droplet in convective condition, was used. The minimum residence time in the chamber and the characteristic length were calculated by adding the reaction time and the vaporization time. Using the characteristic length, the design methods for the fuel-rich gas-generator were established. Finally, a parametric study was achieved for the effects of the O/F ratio, mass flow rate, chamber pressure, initial droplet temperature, initial droplet diameter and initial droplet velocity.

  9. Thermal-structural analysis of regeneratively-cooled thrust chamber wall in reusable LOX/Methane rocket engines

    Directory of Open Access Journals (Sweden)

    Jiawen SONG

    2017-06-01

    Full Text Available To predict the thermal and structural responses of the thrust chamber wall under cyclic work, a 3-D fluid-structural coupling computational methodology is developed. The thermal and mechanical loads are determined by a validated 3-D finite volume fluid-thermal coupling computational method. With the specified loads, the nonlinear thermal-structural finite element analysis is applied to obtaining the 3-D thermal and structural responses. The Chaboche nonlinear kinematic hardening model calibrated by experimental data is adopted to predict the cyclic plastic behavior of the inner wall. The methodology is further applied to the thrust chamber of LOX/Methane rocket engines. The results show that both the maximum temperature at hot run phase and the maximum circumferential residual strain of the inner wall appear at the convergent part of the chamber. Structural analysis for multiple work cycles reveals that the failure of the inner wall may be controlled by the low-cycle fatigue when the Chaboche model parameter γ3 = 0, and the damage caused by the thermal-mechanical ratcheting of the inner wall cannot be ignored when γ3 > 0. The results of sensitivity analysis indicate that mechanical loads have a strong influence on the strains in the inner wall.

  10. Numerical investigation of combustion with non-gray thermal radiation and soot formation effect in a liquid rocket engine

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Doyoung [Department of Aerospace Engineering, Center for Advanced e-System Integration Technology, Konkuk University, 1 Hwayang-Dong, Kwangjin-Gu, Seoul 143-701 (Korea, Republic of); Baek, Seung Wook [Department of Aerospace Engineering, Korea Advanced Institute of Science and Technology, 373-1 Kusong-Dong, Yusung-Gu, Taejon 305-701 (Korea, Republic of)

    2007-02-15

    A numerical analysis was carried out in order to investigate the combustion and heat transfer characteristics in a liquid rocket engine in terms of non-gray thermal radiation and soot formation. Governing gas and droplet phase equations with PSIC model, turbulent combustion model with liquid kerosene fuel, soot formation, and non-gray thermal radiative equations are introduced. A radiation model was implemented in a compressible flow solver in order to investigate the effects of thermal radiation. The finite-volume method (FVM) was employed to solve the radiative transfer equation, and the weighted-sum-of-gray-gases model (WSGGM) was applied to model the radiation effect by a mixture of non-gray gases and gray soot particulates. After confirming the two-phase combustion behavior with soot distribution, the effects of the O/F ratio, wall temperature, and wall emissivity on the wall heat flux were investigated. It was found that the effects of soot formation and radiation are significant; as the O/F ratio increases, the wall temperature decreases. In addition, as the wall emissivity increases, the radiative heat flux on the wall increases. (author)

  11. QUALITY CONTROL AUTOMATED LASER-ULTRASONIC METHOD FOR SOLDER JOINTS OF NOZZLES OF CHAMBERS IN LIQUID ROCKET ENGINES

    Directory of Open Access Journals (Sweden)

    D. S. Sergeev

    2016-01-01

    Full Text Available The paper deals with the problem of quality control for solder joints of nozzles of chambers in liquid rocket engines (LRE. The nozzle of LRE chamber is a responsible product, operating in conditions of high pressure and temperature gradient, having a complex geometric shape and consisting of a large number of milled channels. The analysis of existing methods for solving the problem of quality control of solder joints in LRE nozzles of chambers is carried out. The necessity of the development of an automated laser-ultrasonic control method of solder joints in LRE nozzles of chambers is proved. The analysis of existing automated ultrasonic means of control and the factors affecting control accuracy is carried out. The prototype hardware has been designed for the automated laser ultrasonic nondestructive quality testing of solder joints of LRE nozzles. For software control of the sensor movement mechanism for scanning the inner surface of LRE chamber nozzles and its positioning, the usage of three-layer neural network is proposed. An adaptive algorithm of automated quality control of solder joints has been worked out. A method for the integrated assessment of the quality of solder joints of LRE chambers is suggested. In the process of research methodology was developed for automated measurement of geometrical characteristics of defects and quality control of solder joints in LRE nozzles of chambers. The approbation of the developed method was carried out on three-coordinate automated stand.

  12. Testing of a Liquid Oxygen/Liquid Methane Reaction Control Thruster in a New Altitude Rocket Engine Test Facility

    Science.gov (United States)

    Meyer, Michael L.; Arrington, Lynn A.; Kleinhenz, Julie E.; Marshall, William M.

    2012-01-01

    A relocated rocket engine test facility, the Altitude Combustion Stand (ACS), was activated in 2009 at the NASA Glenn Research Center. This facility has the capability to test with a variety of propellants and up to a thrust level of 2000 lbf (8.9 kN) with precise measurement of propellant conditions, propellant flow rates, thrust and altitude conditions. These measurements enable accurate determination of a thruster and/or nozzle s altitude performance for both technology development and flight qualification purposes. In addition the facility was designed to enable efficient test operations to control costs for technology and advanced development projects. A liquid oxygen-liquid methane technology development test program was conducted in the ACS from the fall of 2009 to the fall of 2010. Three test phases were conducted investigating different operational modes and in addition, the project required the complexity of controlling propellant inlet temperatures over an extremely wide range. Despite the challenges of a unique propellant (liquid methane) and wide operating conditions, the facility performed well and delivered up to 24 hot fire tests in a single test day. The resulting data validated the feasibility of utilizing this propellant combination for future deep space applications.

  13. Rocket engine high-enthalpy flow simulation using heated CO2 gas to verify the development of a rocket nozzle and combustion tests

    Science.gov (United States)

    Takeishi, K.; Ishizaka, K.; Okamoto, J.; Watanabe, Y.

    2017-03-01

    The LE-7A engine is the first-stage engine of the Japanese-made H-IIA launch vehicle. This engine has been developed by improving and reducing the price of the LE-7 engine used in the H-II launch vehicle. In the qualification combustion tests, the original designed LE-7A (LE-7A-OR) engine experienced two major problems, a large side load in the transient state of engine start and stop and melt on nozzle generative cooling tubes. The reason for the troubles of the LE-7A-OR engine was investigated by conducting experimental and numerical studies. In actual engine conditions, the main hot gas stream is a heated steam. Furthermore, the main stream temperature in the nozzle changes from approximately 3500 K at the throat to 500 K at the exit. In such a case, the specific heat ratio changes depending on the temperature. A similarity of the Mach number should be considered when conducting a model flow test with a similar flow condition of the Mach number between an actual engine combustion test and a model flow test. High-speed flow tests were conducted using CO2 gas heated up to 673 K as a working fluid and a 1:12 sub-scaled model nozzle of the LE-7A-OR engine configuration. The problems of the side force and the conducted form of the shock waves generated in the nozzle of the LE-7A-OR engine during engine start and stop were reproduced by the model tests of experimental and numerical investigations. This study presented that the model flow test using heated CO2 gas is useful and effective in verifying the numerical analysis and the design verification before actual engine combustion tests.

  14. Some Interesting Applications of Probabilistic Techiques in Structural Dynamic Analysis of Rocket Engines

    Science.gov (United States)

    Brown, Andrew M.

    2014-01-01

    Numerical and Analytical methods developed to determine damage accumulation in specific engine components when speed variation included. Dither Life Ratio shown to be well over factor of 2 for specific example. Steady-State assumption shown to be accurate for most turbopump cases, allowing rapid calculation of DLR. If hot-fire speed data unknown, Monte Carlo method developed that uses speed statistics for similar engines. Application of techniques allow analyst to reduce both uncertainty and excess conservatism. High values of DLR could allow previously unacceptable part to pass HCF criteria without redesign. Given benefit and ease of implementation, recommend that any finite life turbomachine component analysis adopt these techniques. Probability Values calculated, compared, and evaluated for several industry-proposed methods for combining random and harmonic loads. Two new excel macros written to calculate combined load for any specific probability level. Closed form Curve fits generated for widely used 3(sigma) and 2(sigma) probability levels. For design of lightweight aerospace components, obtaining accurate, reproducible, statistically meaningful answer critical.

  15. Development of a numerical tool to study the mixing phenomenon occurring during mode one operation of a multi-mode ejector-augmented pulsed detonation rocket engine

    Science.gov (United States)

    Dawson, Joshua

    A novel multi-mode implementation of a pulsed detonation engine, put forth by Wilson et al., consists of four modes; each specifically designed to capitalize on flow features unique to the various flow regimes. This design enables the propulsion system to generate thrust through the entire flow regime. The Multi-Mode Ejector-Augmented Pulsed Detonation Rocket Engine operates in mode one during take-off conditions through the acceleration to supersonic speeds. Once the mixing chamber internal flow exceeds supersonic speed, the propulsion system transitions to mode two. While operating in mode two, supersonic air is compressed in the mixing chamber by an upstream propagating detonation wave and then exhausted through the convergent-divergent nozzle. Once the velocity of the air flow within the mixing chamber exceeds the Chapman-Jouguet Mach number, the upstream propagating detonation wave no longer has sufficient energy to propagate upstream and consequently the propulsive system shifts to mode three. As a result of the inability of the detonation wave to propagate upstream, a steady oblique shock system is established just upstream of the convergent-divergent nozzle to initiate combustion. And finally, the propulsion system progresses on to mode four operation, consisting purely of a pulsed detonation rocket for high Mach number flight and use in the upper atmosphere as is needed for orbital insertion. Modes three and four appear to be a fairly significant challenge to implement, while the challenge of implementing modes one and two may prove to be a more practical goal in the near future. A vast number of potential applications exist for a propulsion system that would utilize modes one and two, namely a high Mach number hypersonic cruise vehicle. There is particular interest in the dynamics of mode one operation, which is the subject of this research paper. Several advantages can be obtained by use of this technology. Geometrically the propulsion system is fairly

  16. Hydrogen and Water: An Engineering, Economic and Environmental Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Simon, A J; Daily, W; White, R G

    2010-01-06

    The multi-year program plan for the Department of Energy's Hydrogen and Fuel Cells Technology Program (USDOE, 2007a) calls for the development of system models to determine economic, environmental and cross-cutting impacts of the transition to a hydrogen economy. One component of the hydrogen production and delivery chain is water; water's use and disposal can incur costs and environmental consequences for almost any industrial product. It has become increasingly clear that due to factors such as competing water demands and climate change, the potential for a water-constrained world is real. Thus, any future hydrogen economy will need to be constructed so that any associated water impacts are minimized. This, in turn, requires the analysis and comparison of specific hydrogen production schemes in terms of their water use. Broadly speaking, two types of water are used in hydrogen production: process water and cooling water. In the production plant, process water is used as a direct input for the conversion processes (e.g. steam for Steam Methane Reforming {l_brace}SMR{r_brace}, water for electrolysis). Cooling water, by distinction, is used indirectly to cool related fluids or equipment, and is an important factor in making plant processes efficient and reliable. Hydrogen production further relies on water used indirectly to generate other feedstocks required by a hydrogen plant. This second order indirect water is referred to here as 'embedded' water. For example, electricity production uses significant quantities of water; this 'thermoelectric cooling' contributes significantly to the total water footprint of the hydrogen production chain. A comprehensive systems analysis of the hydrogen economy includes the aggregate of the water intensities from every step in the production chain including direct, indirect, and embedded water. Process and cooling waters have distinct technical quality requirements. Process water, which is typically

  17. Torpedo Rockets

    Science.gov (United States)

    2004-01-01

    All through the 13th to the 15th Centuries there were reports of many rocket experiments. For example, Joanes de Fontana of Italy designed a surface-rurning, rocket-powered torpedo for setting enemy ships on fire

  18. 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)

  19. High-frequency combustion instability control through acoustic modulation at the inlet boundary for liquid rocket engine applications

    Science.gov (United States)

    Bennewitz, John William

    model-predicted mode stability transition was consistent with experimental observations, supporting the premise that inlet acoustic modulation is a means to control high-frequency combustion instabilities. From the modal analysis, it may be deduced that the inlet impedance provides a damping mechanism for instability suppression. Combined, this work demonstrates the strategic application of acoustic modulation within an injector as a potential method to control high-frequency combustion instabilities for liquid rocket engine applications.

  20. Crystal engineering with urea and thiourea hydrogen-bonding groups

    Energy Technology Data Exchange (ETDEWEB)

    Custelcean, Radu [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division

    2007-09-11

    The utilization of N,N$'$-disubstituted ureas and thioureas as design elements in the synthesis of crystalline organic solids is reviewed. In conclusion, these hydrogen-bonding units are versatile yet predictable building blocks that can be rationally employed in both crystal assembly and functionalization.

  1. Application of powder metallurgy techniques to produce improved bearing elements for liquid rocket engines

    Science.gov (United States)

    Moracz, D. J.; Shipley, R. J.; Moxson, V. S.; Killman, R. J.; Munson, H. E.

    1992-01-01

    The objective was to apply powder metallurgy techniques for the production of improved bearing elements, specifically balls and races, for advanced cryogenic turbopump bearings. The materials and fabrication techniques evaluated were judged on the basis of their ability to improve fatigue life, wear resistance, and corrosion resistance of Space Shuttle Main Engine (SSME) propellant bearings over the currently used 440C. An extensive list of candidate bearing alloys in five different categories was considered: tool/die steels, through hardened stainless steels, cobalt-base alloys, and gear steels. Testing of alloys for final consideration included hardness, rolling contact fatigue, cross cylinder wear, elevated temperature wear, room and cryogenic fracture toughness, stress corrosion cracking, and five-ball (rolling-sliding element) testing. Results of the program indicated two alloys that showed promise for improved bearing elements. These alloys were MRC-2001 and X-405. 57mm bearings were fabricated from the MRC-2001 alloy for further actual hardware rig testing by NASA-MSFC.

  2. Improvement of diesel engine ecological and economic parameters by using hydrogen

    Directory of Open Access Journals (Sweden)

    Dalius KALISINSKAS

    2013-01-01

    Full Text Available Exhaustion and rising cost of fossil energy resources stimulates the search of ways to minimize their consumption. In the transport sector the main energy source is liquid fuel. Due to combustion of that fuel noxious gas is being emitted to atmosphere and creates the “greenhouse” effect, as well, as smog. Reduction of oil reserves increases the price of fuel as well, therefore the search for various alternatives is being made. One of them is usage of hydrogen as a supplement to the traditional fuel. During combustion of hydrogen toxic gases are not emitted. For obtaining hydrogen in a car a hydrogen generator which extracts it from water by electrolysis usually is used. The benefit of using hydrogen is better efficiency of an internal combustion engine. Hydrogen helps to reduce fuel consumption and emission of noxious gas as well. Research of efficiency and emissions of an internal combustion engine using hydrogen as an additive to the traditional fuel has been carried out, computational model to determine fuel costs and exhaust gas emissions under different working conditions has been developed.

  3. Generation of oxy-hydrogen gas and its effect on performance of spark ignition engine

    Science.gov (United States)

    Patil, N. N.; Chavan, C. B.; More, A. S.; Baskar, P.

    2017-11-01

    Considering the current scenario of petroleum fuels, it has been observed that, they will last for few years from now. On the other hand, the ever increasing cost of a gasoline fuels and their related adverse effects on environment caught the attention of researchers to find a supplementary source. For commercial fuels, supplementary source is not about replacing the entire fuel, instead enhancing efficiency by simply making use of it in lesser amount. From the recent research that has been carried out, focus on the use of Hydrogen rich gas as a supplementary source of fuel has increased. But the problem related to the storage of hydrogen gas confines the application of pure hydrogen in petrol engine. Using oxy-hydrogen gas (HHO) generator the difficulties of storing the hydrogen have overcome up to a certain limit. The present study highlights on performance evaluation of conventional petrol engine by using HHO gas as a supplementary fuel. HHO gas was generated from the electrolysis of water. KOH solution of 3 Molar concentration was used which act as a catalyst and accelerates the rate of generation of HHO gas. Quantity of gas to be supplied to the engine was controlled by varying amount of current. It was observed that, engine performance was improved on the introduction of HHO gas.

  4. A Framework for Assessing the Reusability of Hardware (Reusable Rocket Engines)

    Science.gov (United States)

    Childress-Thompson, Rhonda; Thomas, Dale; Farrington, Phillip

    2016-01-01

    Within the space flight community, reusability has taken center stage as the new buzzword. In order for reusable hardware to be competitive with its expendable counterpart, two major elements must be closely scrutinized. First, recovery and refurbishment costs must be lower than the development and acquisition costs. Additionally, the reliability for reused hardware must remain the same (or nearly the same) as "first use" hardware. Therefore, it is imperative that a systematic approach be established to enhance the development of reusable systems. However, before the decision can be made on whether it is more beneficial to reuse hardware or to replace it, the parameters that are needed to deem hardware worthy of reuse must be identified. For reusable hardware to be successful, the factors that must be considered are reliability (integrity, life, number of uses), operability (maintenance, accessibility), and cost (procurement, retrieval, refurbishment). These three factors are essential to the successful implementation of reusability while enabling the ability to meet performance goals. Past and present strategies and attempts at reuse within the space industry will be examined to identify important attributes of reusability that can be used to evaluate hardware when contemplating reusable versus expendable options. This paper will examine why reuse must be stated as an initial requirement rather than included as an afterthought in the final design. Late in the process, changes in the overall objective/purpose of components typically have adverse effects that potentially negate the benefits. A methodology for assessing the viability of reusing hardware will be presented by using the Space Shuttle Main Engine (SSME) to validate the approach. Because reliability, operability, and costs are key drivers in making this critical decision, they will be used to assess requirements for reuse as applied to components of the SSME.

  5. Numerical analysis of hydrogen and methane propagation during testing of combustion engines

    Directory of Open Access Journals (Sweden)

    Dvořák V.

    2007-10-01

    Full Text Available The research of gas-fuelled combustion engines using hydrogen or methane require accordingly equipped test benches which take respect to the higher dangerous of self ignition accidents. This article deals with numerical calculations of flow in laboratory during simulated leakage of gas-fuel from fuel system of tested engine. The influences of local suction and influences of roof exhausters on the flow in the laboratory and on the gas propagation are discussed. Results obtained for hydrogen and for methane are compared. Conclusions for design and performance of suction devices and test benches are deduced from these results.

  6. Experimental study of hydrogen as a fuel additive in internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Saanum, Inge

    2008-07-01

    Combustion of hydrocarbons in internal combustion engines results in emissions that can be harmful both to human health and to the environment. Although the engine technology is improving, the emissions of NO{sub x}, PM and UHC are still challenging. Besides, the overall consumption of fossil fuel and hence the emissions of CO{sub 2} are increasing because of the increasing number of vehicles. This has lead to a focus on finding alternative fuels and alternative technologies that may result in lower emissions of harmful gases and lower CO{sub 2} emissions. This thesis treats various topics that are relevant when using blends of fuels in different internal combustion engine technologies, with a particular focus on using hydrogen as a fuel additive. The topics addressed are especially the ones that impact the environment, such as emissions of harmful gases and thermal efficiency (fuel consumption). The thesis is based on experimental work performed at four different test rigs: 1. A dynamic combustion rig with optical access to the combustion chamber where spark ignited premixed combustion could be studied by means of a Schlieren optical setup and a high speed video camera. 2. A spark ignition natural gas engine rig with an optional exhaust gas recycling system. 3. A 1-cylinder diesel engine prepared for homogeneous charge compression ignition combustion. 4. A 6-cylinder standard diesel engine The engine rigs were equipped with cylinder pressure sensors, engine dynamometers, exhaust gas analyzers etc. to enable analyses of the effects of different fuels. The effect of hydrogen blended with methane and natural gas in spark ignited premixed combustion was investigated in the dynamic combustion rig and in a natural gas engine. In the dynamic combustion rig, the effect of hydrogen added to methane on the flame speed and the flame structure was investigated at elevated pressure and temperature. A considerable increase in the flame speed was observed when adding 30 vol

  7. Disturbing effect of free hydrogen on fuel combustion in internal combustion engines

    Science.gov (United States)

    Riedler, A

    1923-01-01

    Experiments with fuel mixtures of varying composition, have recently been conducted by the Motor Vehicle and Airplane Engine Testing Laboratories of the Royal Technical High School in Berlin and at Fort Hahneberg, as well as at numerous private engine works. The behavior of hydrogen during combustion in engines and its harmful effect under certain conditions, on the combustion in the engine cylinder are of general interest. Some of the results of these experiments are given here, in order to elucidate the main facts and explain much that is already a matter of experience with chauffeurs and pilots.

  8. Some typical solid propellant rocket motors

    NARCIS (Netherlands)

    Zandbergen, B.T.C.

    2013-01-01

    Typical Solid Propellant Rocket Motors (shortly referred to as Solid Rocket Motors; SRM's) are described with the purpose to form a database, which allows for comparative analysis and applications in practical SRM engineering.

  9. Potentials of NO{sub X} emission reduction methods in SI hydrogen engines: Simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Safari, H.; Jazayeri, S.A. [Department of Mechanical Engineering, K.N. Toosi University of Technology, No.15, Pardis Street, Vanak Square, Tehran (Iran); Ebrahimi, R. [Department of Aerospace Engineering, K.N. Toosi University of Technology, 4th Tehranpars Square, East Vafadar Street, Tehran (Iran)

    2009-01-15

    The ever increasing cost of hydrocarbon fuels and more stringent emission standards may resolve challenges in producing hydrogen and using it as an alternative fuel in industries. Internal combustion engines are well-established technology and hydrogen fuel in such engines is considered as an attractive choice in exploiting clean, efficient and renewable hydrogen energy. This work presents an improved thermo-kinetics model for simulation of hydrogen combustion in SI engines. The turbulent propagating flame is modeled using turbulent burning velocity model. During combustion the charge is divided into three zones containing unburned charge, flame and burned gas. The adiabatic flame is assumed to be in thermodynamic equilibrium while the detailed chemical kinetics scheme is considered for burned and unburned zones. The results were first validated against published experiments. Good agreements were obtained between simulation and experiment for varying equivalence ratio, ignition timing and compression ratio. Detailed analysis of engine NO{sub X} emission was performed afterward. The lean-burn and EGR strategies' potentials were examined by the current model. The effects of different amounts of cooled dry EGR and hot wet EGR on the NO{sub X} emission, engine power output and indicated thermal efficiency were investigated and compared theoretically. (author)

  10. In vitro metabolic engineering of hydrogen production at theoretical yield from sucrose.

    Science.gov (United States)

    Myung, Suwan; Rollin, Joseph; You, Chun; Sun, Fangfang; Chandrayan, Sanjeev; Adams, Michael W W; Zhang, Y-H Percival

    2014-07-01

    Hydrogen is one of the most important industrial chemicals and will be arguably the best fuel in the future. Hydrogen production from less costly renewable sugars can provide affordable hydrogen, decrease reliance on fossil fuels, and achieve nearly zero net greenhouse gas emissions, but current chemical and biological means suffer from low hydrogen yields and/or severe reaction conditions. An in vitro synthetic enzymatic pathway comprised of 15 enzymes was designed to split water powered by sucrose to hydrogen. Hydrogen and carbon dioxide were spontaneously generated from sucrose or glucose and water mediated by enzyme cocktails containing up to 15 enzymes under mild reaction conditions (i.e. 37°C and atm). In a batch reaction, the hydrogen yield was 23.2mol of dihydrogen per mole of sucrose, i.e., 96.7% of the theoretical yield (i.e., 12 dihydrogen per hexose). In a fed-batch reaction, increasing substrate concentration led to 3.3-fold enhancement in reaction rate to 9.74mmol of H2/L/h. These proof-of-concept results suggest that catabolic water splitting powered by sugars catalyzed by enzyme cocktails could be an appealing green hydrogen production approach. Copyright © 2014 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  11. Easier Analysis With Rocket Science

    Science.gov (United States)

    2003-01-01

    Analyzing rocket engines is one of Marshall Space Flight Center's specialties. When Marshall engineers lacked a software program flexible enough to meet their needs for analyzing rocket engine fluid flow, they overcame the challenge by inventing the Generalized Fluid System Simulation Program (GFSSP), which was named the co-winner of the NASA Software of the Year award in 2001. This paper describes the GFSSP in a wide variety of applications

  12. THE HYDROGEN-FUELLED INTERNAL COMBUSTION ENGINES FOR MARINE APPLICATIONS WITH A CASE STUDY

    Directory of Open Access Journals (Sweden)

    Ibrahim S. Seddiek

    2015-03-01

    Full Text Available Modern marine power plants have been designed to improve the overall ship’s efficiency. This pushed the designers of marine machinery to search for unconventional fuels for these plants. During the previous years, diesel oil has been extensively used on-board ships. Due to the high price of light diesel oil and the environmental problems resulting from the use of heavy fuel oil, it has become necessary to search for an alternative to traditional fuels. As a result, natural gas fuel has been used on-board some types of ships, especially short-voyage cruise ships. Unfortunately, there are still some technical and logistic problems related to the use of natural gas as a fuel, especially as it is considered a non-renewable energy source. The use of hydrogen fuel on-board ships, particularly in modern power plants may contribute to overcoming the above problems. The present paper considers the possibility of the use of hydrogen fuel for marine applications and discusses different stages of hydrogen gas cycle beginning with hydrogen generation process from clean energy until using it as fuel for internal combustion engines on-board one RO/RO ship, named Taba, operating in the Mediterranean Sea. Compared to the diesel engine, the hydrogen fuelled engine is found to be lower in thermal efficiency and fuel consumption, however, some adjustments are needed.

  13. Study of Knocking Effect in Compression Ignition Engine with Hydrogen as a Secondary Fuel

    Directory of Open Access Journals (Sweden)

    R. Sivabalakrishnan

    2014-01-01

    Full Text Available The aim of this project is detecting knock during combustion of biodiesel-hydrogen fuel and also the knock is suppressed by timed injection of diethyl ether (DEE with biodiesel-hydrogen fuel for different loads. Hydrogen fuel is an effective alternate fuel in making a pollution-free environment with higher efficiency. The usage of hydrogen in compression ignition engine leads to production of knocking or detonation because of its lower ignition energy, wider flammability range, and shorter quenching distance. Knocking combustion causes major engine damage, and also reduces the efficiency. The method uses the measurement and analysis of cylinder pressure signal for various loads. The pressure signal is to be converted into frequency domain that shows the accurate knocking combustion of fuel mixtures. The variation of pressure signal is gradually increased and smoothly reduced to minimum during normal combustion. The rapid rise of pressure signal has occurred during knocking combustion. The experimental setup was mainly available for evaluating the feasibility of normal combustion by comparing with the signals from both fuel mixtures in compression ignition engine. This method provides better results in predicting the knocking feature of biodiesel-hydrogen fuel and the usage of DEE provides complete combustion of fuels with higher performance, and lower emission.

  14. Grain-boundary engineering markedly reduces susceptibility to intergranular hydrogen embrittlement in metallic materials

    Energy Technology Data Exchange (ETDEWEB)

    Bechtle, Sabine; Kumar, Mukul; Somerday, Brian P.; Launey, Maximilien E.; Ritchie, Robert O.

    2009-05-10

    The feasibility of using 'grain-boundary engineering' techniques to reduce the susceptibility of a metallic material to intergranular embrittlement in the presence of hydrogen is examined. Using thermomechanical processing, the fraction of 'special' grain boundaries was increased from 46% to 75% (by length) in commercially pure nickel samples. In the presence of hydrogen concentrations between 1200 and 3400 appm, the high special fraction microstructure showed almost double the tensile ductility; also, the proportion of intergranular fracture was significantly lower and the J{sub c} fracture toughness values were some 20-30% higher in comparison with the low special fraction microstructure. We attribute the reduction in the severity of hydrogen-induced intergranular embrittlement to the higher fraction of special grain boundaries, where the degree of hydrogen segregation at these boundaries is reduced.

  15. Hazards Induced by Breach of Liquid Rocket Fuel Tanks: Conditions and Risks of Cryogenic Liquid Hydrogen-Oxygen Mixture Explosions

    CERN Document Server

    Osipov, Viatcheslav; Hafiychuk, Halyna; Ponizovskaya-Devine, Ekaterina; Smelyanskiy, Vadim; Mathias, Donovan; Lawrence, Scott; Werkheiser, Mary

    2010-01-01

    We analyze the data of purposeful rupture experiments with LOx and LH2 tanks, the Hydrogen-Oxygen Vertical Impact (HOVI) tests that were performed to clarify the ignition mechanisms, the explosive power of cryogenic H2/Ox mixtures under different conditions, and to elucidate the puzzling source of the initial formation of flames near the intertank section during the Challenger disaster. We carry out a physics-based analysis of general explosions scenarios for cryogenic gaseous H2/Ox mixtures and determine their realizability conditions, using the well-established simplified models from the detonation and deflagration theory. We study the features of aerosol H2/Ox mixture combustion and show, in particular, that aerosols intensify the deflagration flames and can induce detonation for any ignition mechanism. We propose a cavitation-induced mechanism of self-ignition of cryogenic H2/Ox mixtures that may be realized when gaseous H2 and Ox flows are mixed with a liquid Ox turbulent stream, as occurred in all HOVI ...

  16. Low thrust chemical rocket technology

    Science.gov (United States)

    Schneider, Steven J.

    1992-01-01

    performance propellants were evaluated: Space storable propellants, including liquid oxygen (LOX) as the oxidizer with nitrogen hydrides or hydrocarbon as fuels. Specifically, a LOX/hydrazine engine was designed, fabricated, and shown to have a 95 pct theoretical c-star which translates into a projected vacuum specific impulse of 345 seconds at an area ratio of 204:1. Further performance improvment can be obtained by the use of LOX/hydrogen propellants, especially for manned spacecraft applications, and specific designs must be developed and advanced through flight qualification.

  17. Biofuel and Hydrogen Influence for Operation Parameters of Spark Ignition Engine

    Directory of Open Access Journals (Sweden)

    Martynas Damaševičius

    2016-12-01

    Full Text Available Paper presents research of efficient and ecological parameters of gasoline engine working with biobuthanol (10% and 20% by volume and addi-tionaly supplying oxygen and hydrogen (HHO gas mixture (3.6 l/min, which was obtained from from water by electrolysis. Biobuthanol addition decreases rate of heat release, the combustion temperature and pressure are lower, which has an influence on lower nitrous oxide (NOx emission in exhaust gases. However, biobuthanol increases carbon monoxide (CO concentration. Biobuthanol fuel has a simplier molecular structure, therefore the concentration of HC in the exhaust gas is decreasing. Due to lower heating value of biobuthanol fuel and slower combustion process, the engine efficiency decreases and specific fuel consumptions increase. The change of engine energetical indicators due to biobuthanol, can be compensated with advanced ignition angle. Using experimental investigation, it was determined, that negative biobuthanol influence for the combustion process and engine efficient inicators can be compensated also by additional supplied HHO gas, in which the hydrogen element iprove fuel mixture com-bustion. Fuel combustion process analysis was carried out using AVL BOOST software. Experimental research and combustion process numerical simulation showed that using balanced biobuthanol and hydrogen addition, optimal efficient and ecological parameters could be achieved, when engine is working for petrol fuel typical optimal spark timing.

  18. An Approximate Analysis of the Inner Wall Loading of a Bimetallic Camera Shell of Reusable Rocket Engine

    Directory of Open Access Journals (Sweden)

    V. S. Zarubin

    2016-01-01

    Full Text Available Various technical devices quite widely use bimetallic shells as the structural elements. A chamber combustion design of the liquid rocket engine (LRE is a typical use of the bimetallic shells.In LRE operation a combustion chamber shell is subject to intense thermal and mechanical effects, which necessitates cooling. A cooling shell path is formed by a gap between its inner and outer walls connected to each other by milled or grooved spacer ribs. The outer wall of the shell serves as a load-bearing element, the inner wall is in direct contact with high-temperature combustion products and exposed to intense heat. The difference in functions of shell walls calls for their manufacturing from different materials with different thermophysical and mechanical properties.Interaction between the shell walls of different materials in heating and cooling leads to emerging thermal strains of various values in the walls. In terms of mechanical properties the inner wall material, usually ranks below the outer wall material strength, which uses the high strength stainless steel 12Х21Н5Т. The inner wall is typically made from copper-based highly heat-conductive alloys. (eg.: chromium bronze. Therefore, the result of the difference in temperature deformations, arising in the walls,  is inelastic nonisothermal strain of the inner wall material with (usually elastic behavior of the outer wall material.For reusable LRE, a cyclic sequence of the loading steps of the inner wall can lead to accumulating damages in its material because of the low-cycle fatigue and cause destruction of the wall or the loss of the cooling tract tightness. The main parameter that determines the level of low-cycle fatigue, is an absolute value of the accumulated inelastic strain (both plastic and evolving over time creep deformation. Quantitative evaluation of this parameter involves analysis of the inner wall loading with multiple starts and shutdowns of LRE. The paper represents an

  19. A laboratory model of a hydrogen/oxygen engine for combustion and nozzle studies

    Science.gov (United States)

    Morren, Sybil H.; Myers, Roger M.; Benko, Stephen E.; Arrington, Lynn A.; Reed, Brian D.

    1993-06-01

    A small laboratory diagnostic thruster was developed in order to evaluate approaches for the use of temperature and pressure sensors for the investigation of low thrust rocket flowfields. Tests were performed at chamber pressures of about 255 kPa, 370 kPa, and 500 kPa with oxidizer/fuel mixture ratios between 4.0 and 8.0. Two gaseous hydrogen/gaseous oxygen injector designs were tested with 60 and 75 fuel film cooling. The results of hot-wire tests showed the thruster and instrumentation designs to be effective. Azimuthal temperature distributions were found to be a function of operating conditions and hardware configuration. Results indicated that small differences in injector design can result in dramatically different thruster performance and wall temperature behavior. However, the importance of these injector effects may be decreased by operating at a high fuel film cooling rate.

  20. Neutron imaging of hydrogen-rich fluids in geomaterials and engineered porous media: A review

    Science.gov (United States)

    Perfect, E.; Cheng, C.-L.; Kang, M.; Bilheux, H. Z.; Lamanna, J. M.; Gragg, M. J.; Wright, D. M.

    2014-02-01

    Recent advances in visualization technologies are providing new discoveries as well as answering old questions with respect to the phase structure and flow of hydrogen-rich fluids, such as water and oil, within porous media. Magnetic resonance and x-ray imaging are sometimes employed in this context, but are subject to significant limitations. In contrast, neutrons are ideally suited for imaging hydrogen-rich fluids in abiotic non-hydrogenous porous media because they are strongly attenuated by hydrogen and can "see" through the solid matrix in a non-destructive fashion. This review paper provides an overview of the general principles behind the use of neutrons to image hydrogen-rich fluids in both 2-dimensions (radiography) and 3-dimensions (tomography). Engineering standards for the neutron imaging method are examined. The main body of the paper consists of a comprehensive review of the diverse scientific literature on neutron imaging of static and dynamic experiments involving variably-saturated geomaterials (rocks and soils) and engineered porous media (bricks and ceramics, concrete, fuel cells, heat pipes, and porous glass). Finally some emerging areas that offer promising opportunities for future research are discussed.

  1. Effect of using hydrogen in the power and performance of an internal combustion engine

    Directory of Open Access Journals (Sweden)

    Edwin Tamayo

    2016-12-01

    Full Text Available This study analyzed the real working parameters of an Otto cycle internal combustion engine, using as fuel hydrogen plus gasoline. Two stoichiometric equations were determined. In the first equation, the reagents are octane and air, in the second equation was added the quantity of 3.86 H2 moles obtained from a hydrogen cell. Two sets of equations, for consumption and power, were determined from the chemical equations, working at the conditions of Quito: altitude 2850 msnm, 72.794 kPa of atmospheric pressure and 300 K of temperature. A single cylinder engine powered with hydrogen plus gasoline was used for getting real data of engine power, using mixtures of air-gasoline and hydrogen; the theoretical power without H2 was 3.91 HP and with H2 5.41 HP, it increased 27.1%, the real power is 3.78 HP without H2 and 4.66 HP with H2, it increased 16.7%. Theoretical fuel consumption is 401.61 g/kWh and addition of H2 is less to 373.52 g/kWh, the actual consumption that indicates the manufacturer is 395 g/kWh.

  2. Rotating and positive-displacement pumps for low-thrust rocket engines. Volume 1: Pump Evaluation and design. [of centrifugal pumps

    Science.gov (United States)

    Macgregor, C.; Csomor, A.

    1974-01-01

    Rotating and positive displacement pumps of various types were studied for pumping liquid fluorine for low-thrust, high-performance rocket engines. Included in the analysis were: centrifugal, pitot, Barske, Tesla, drag, gear, vane, axial piston, radial piston, diaphragm, and helirotor pump concepts. The centrifugal pump and the gear pump were selected and these were carried through detailed design and fabrication. Mechanical difficulties were encountered with the gear pump during the preliminary tests in Freon-12. Further testing and development was therefore limited to the centrifugal pump. Tests on the centrifugal pump were conducted in Freon-12 to determine the hydrodynamic performance and in liquid fluorine to demonstrate chemical compatibility.

  3. Rocket Combustion Chamber Coating

    Science.gov (United States)

    Holmes, Richard R. (Inventor); McKechnie, Timothy N. (Inventor)

    2001-01-01

    A coating with the ability to protect (1) the inside wall (i.e., lining) of a rocket engine combustion chamber and (2) parts of other apparatuses that utilize or are exposed to combustive or high temperature environments. The novelty of this invention lies in the manner a protective coating is embedded into the lining.

  4. Simulation of performance and nitrogen oxide formation of a hydrogen-enriched diesel engine with the steam injection method

    Directory of Open Access Journals (Sweden)

    Gonca Guven

    2015-01-01

    Full Text Available In the present study, steam injection method (SIM is implemented to a hydrogen-enriched diesel engine in order to improve the levels of performance and NO emissions. As hydrogen enrichment method increases effective efficiency, NO emissions could be increased. However, the SIM is used to control NO emissions and improve the engine performance. Due to these positive effects, hydrogen enrichment and the SIMare applied into a diesel engine by using a two-zone combustion model for30% hydrogen enrichment of the fuel volume and 20% steam ratio of the fuel mass at full load conditions. The results obtained are compared with conventional diesel engine (D, steam injected diesel engine (D+S20, hydrogen-enriched diesel engine (D+H30 and hydrogen-enriched diesel engine with steam injection (D+H30+S20 in terms of performance and NO emissions. In the results, the effective efficiency and effective power improve up to 22.8% and %3.1, as NO emissions decrease up to 22.1%. Hence, the hydrogen enrichment with steam injection method is more environmentally friendly with better performance.

  5. Engineering Synechocystis PCC6803 for hydrogen production: influence on the tolerance to oxidative and sugar stresses.

    Directory of Open Access Journals (Sweden)

    Marcia Ortega-Ramos

    Full Text Available In the prospect of engineering cyanobacteria for the biological photoproduction of hydrogen, we have studied the hydrogen production machine in the model unicellular strain Synechocystis PCC6803 through gene deletion, and overexpression (constitutive or controlled by the growth temperature. We demonstrate that the hydrogenase-encoding hoxEFUYH operon is dispensable to standard photoautotrophic growth in absence of stress, and it operates in cell defense against oxidative (H₂O₂ and sugar (glucose and glycerol stresses. Furthermore, we showed that the simultaneous over-production of the proteins HoxEFUYH and HypABCDE (assembly of hydrogenase, combined to an increase in nickel availability, led to an approximately 20-fold increase in the level of active hydrogenase. These novel results and mutants have major implications for those interested in hydrogenase, hydrogen production and redox metabolism, and their connections with environmental conditions.

  6. Application of C/C composites to the combustion chamber of rocket engines. Part 1: Heating tests of C/C composites with high temperature combustion gases

    Science.gov (United States)

    Tadano, Makoto; Sato, Masahiro; Kuroda, Yukio; Kusaka, Kazuo; Ueda, Shuichi; Suemitsu, Takeshi; Hasegawa, Satoshi; Kude, Yukinori

    1995-04-01

    Carbon fiber reinforced carbon composite (C/C composite) has various superior properties, such as high specific strength, specific modulus, and fracture strength at high temperatures of more than 1800 K. Therefore, C/C composite is expected to be useful for many structural applications, such as combustion chambers of rocket engines and nose-cones of space-planes, but C/C composite lacks oxidation resistivity in high temperature environments. To meet the lifespan requirement for thermal barrier coatings, a ceramic coating has been employed in the hot-gas side wall. However, the main drawback to the use of C/C composite is the tendency for delamination to occur between the coating layer on the hot-gas side and the base materials on the cooling side during repeated thermal heating loads. To improve the thermal properties of the thermal barrier coating, five different types of 30-mm diameter C/C composite specimens constructed with functionally gradient materials (FGM's) and a modified matrix coating layer were fabricated. In this test, these specimens were exposed to the combustion gases of the rocket engine using nitrogen tetroxide (NTO) / monomethyl hydrazine (MMH) to evaluate the properties of thermal and erosive resistance on the thermal barrier coating after the heating test. It was observed that modified matrix and coating with FGM's are effective in improving the thermal properties of C/C composite.

  7. Predicting performance of axial pump inducer of LOX booster turbo-pump of staged combustion cycle based rocket engine using CFD

    Science.gov (United States)

    Mishra, Arpit; Ghosh, Parthasarathi

    2015-12-01

    For low cost, high thrust, space missions with high specific impulse and high reliability, inert weight needs to be minimized and thereby increasing the delivered payload. Turbopump feed system for a liquid propellant rocket engine (LPRE) has the highest power to weight ratio. Turbopumps are primarily equipped with an axial flow inducer to achieve the high angular velocity and low suction pressure in combination with increased system reliability. Performance of the turbopump strongly depends on the performance of the inducer. Thus, for designing a LPRE turbopump, demands optimization of the inducer geometry based on the performance of different off-design operating regimes. In this paper, steady-state CFD analysis of the inducer of a liquid oxygen (LOX) axial pump used as a booster pump for an oxygen rich staged combustion cycle rocket engine has been presented using ANSYS® CFX. Attempts have been made to obtain the performance characteristic curves for the LOX pump inducer. The formalism has been used to predict the performance of the inducer for the throttling range varying from 80% to 113% of nominal thrust and for the different rotational velocities from 4500 to 7500 rpm. The results have been analysed to determine the region of cavitation inception for different inlet pressure.

  8. Emission estimation of neat paradise tree oil combustion assisted with superheated hydrogen in a 4-stroke natural aspirated DICI engine

    Directory of Open Access Journals (Sweden)

    Sundararajan Karthikayan

    2016-01-01

    Full Text Available This research work investigates the use of neat paradise tree oil in a 4-stroke natural aspirated direct injection compression ignition engine assisted with the help of super-heated hydrogen (hydrogen in gaseous state or above its saturation temperature as a combustion improver. The high calorific gaseous fuel hydrogen gas was used as a combustion improver and admitted into the engine during the suction stroke. A 4-stroke single cylinder Diesel engine was chosen and its operating parameters were suitably modified. Neat paradise tree oil was admitted through standard injector of the engine and hydrogen was admitted through induction manifold. Inducted super-heated hydrogen was initiated the intermediate compounds combustion of neat paradise tree oil. This process offers higher temperature combustion and results in complete combustion of heavier molecules of neat paradise tree oil within shorter duration. The results of the experiment reveal that 40% higher NOx, 20% lower smoke, 5% lower CO, and 45% lower HC than that of neat paradise tree oil fuel operation and the admission of superheated hydrogen has improved the combustion characteristics of neat paradise tree oil. The investigation successfully proved that the application of neat paradise tree oil with 15% of hydrogen improver is possible under a regular Diesel engine with minimal engine modification.

  9. Determination of operating parameters of industrial engine fuelled with post processing gases with high hydrogen content

    Science.gov (United States)

    Brzeżański, M.; Mareczek, M.; Marek, W.; Papuga, T.

    2016-09-01

    The results of investigations of SI engine fuelled with hydrogen and mixed n-butanol with isobutanol have been presented in article. The idea of flexible feeding system and the aim and methodology of carried out measurement have been also described. Obtained results have been compared to the results of tests carried out during flexible feeding of the same engine. The proposed control system enables not only application of different liquid and gaseous fuels but also application of the fuels which chemical composition vary within the relatively short time intervals.

  10. Fundamentals of aircraft and rocket propulsion

    CERN Document Server

    El-Sayed, Ahmed F

    2016-01-01

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

  11. Advancement of Systems Designs and Key Engineering Technologies for Materials Based Hydrogen Storage

    Energy Technology Data Exchange (ETDEWEB)

    van Hassel, Bart A. [United Technologies Research Center, East Hartford, CT (United States)

    2015-09-18

    UTRC lead the development of the Simulink Framework model that enables a comparison of different hydrogen storage systems on a common basis. The Simulink Framework model was disseminated on the www.HSECoE.org website that is hosted by NREL. UTRC contributed to a better understanding of the safety aspects of the proposed hydrogen storage systems. UTRC also participated in the Failure Mode and Effect Analysis of both the chemical- and the adsorbent-based hydrogen storage system during Phase 2 of the Hydrogen Storage Engineering Center of Excellence. UTRC designed a hydrogen storage system with a reversible metal hydride material in a compacted form for light-duty vehicles with a 5.6 kg H2 storage capacity, giving it a 300 miles range. It contains a heat exchanger that enables efficient cooling of the metal hydride material during hydrogen absorption in order to meet the 3.3 minute refueling time target. It has been shown through computation that the kinetics of hydrogen absorption of Ti-catalyzed NaAlH4 was ultimately limiting the rate of hydrogen absorption to 85% of the material capacity in 3.3 minutes. An inverse analysis was performed in order to determine the material property requirements in order for a metal hydride based hydrogen storage system to meet the DOE targets. Work on metal hydride storage systems was halted after the Phase 1 to Phase 2 review due to the lack of metal hydride materials with the required material properties. UTRC contributed to the design of a chemical hydrogen storage system by developing an adsorbent for removing the impurity ammonia from the hydrogen gas, by developing a system to meter the transport of Ammonia Borane (AB) powder to a thermolysis reactor, and by developing a gas-liquid-separator (GLS) for the separation of hydrogen gas from AB slurry in silicone oil. Stripping impurities from hydrogen gas is essential for a long life of the fuel cell system on board of a vehicle. Work on solid transport of AB was halted after the

  12. Effect of hydrogen addition on the performance of a biogas fuelled spark ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Porpatham, E.; Ramesh, A.; Nagalingam, B. [Internal Combustion Engines Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600 036 (India)

    2007-08-15

    Hydrogen was added in small amounts (5%, 10% and 15% on the energy basis) to biogas and tested in a spark ignition engine at constant speed at different equivalence ratios to study the effects on performance, emissions and combustion. Hydrogen significantly enhances the combustion rate and extends the lean limit of combustion of biogas. There is an improvement in brake thermal efficiency and brake power. However, beyond 15% hydrogen the need to retard the ignition timing to control knock does not lead to improvements at high equivalence ratios. Significant reductions in hydrocarbon levels were seen. There was no increase in nitric oxide emissions due to the use of retarded ignition timing and the presence of carbon dioxide. Peak pressures and heat release rates are lower with hydrogen addition as the ignition timing is to be retarded to avoid knock. There is a reduction in cycle-by-cycle variations in combustion with lean mixtures. On the whole 10% hydrogen addition was found to be the most suitable. (author)

  13. Hydrocarbon Rocket Technology Impact Forecasting

    Science.gov (United States)

    Stuber, Eric; Prasadh, Nishant; Edwards, Stephen; Mavris, Dimitri N.

    2012-01-01

    Ever since the Apollo program ended, the development of launch propulsion systems in the US has fallen drastically, with only two new booster engine developments, the SSME and the RS-68, occurring in the past few decades.1 In recent years, however, there has been an increased interest in pursuing more effective launch propulsion technologies in the U.S., exemplified by the NASA Office of the Chief Technologist s inclusion of Launch Propulsion Systems as the first technological area in the Space Technology Roadmaps2. One area of particular interest to both government agencies and commercial entities has been the development of hydrocarbon engines; NASA and the Air Force Research Lab3 have expressed interest in the use of hydrocarbon fuels for their respective SLS Booster and Reusable Booster System concepts, and two major commercially-developed launch vehicles SpaceX s Falcon 9 and Orbital Sciences Antares feature engines that use RP-1 kerosene fuel. Compared to engines powered by liquid hydrogen, hydrocarbon-fueled engines have a greater propellant density (usually resulting in a lighter overall engine), produce greater propulsive force, possess easier fuel handling and loading, and for reusable vehicle concepts can provide a shorter turnaround time between launches. These benefits suggest that a hydrocarbon-fueled launch vehicle would allow for a cheap and frequent means of access to space.1 However, the time and money required for the development of a new engine still presents a major challenge. Long and costly design, development, testing and evaluation (DDT&E) programs underscore the importance of identifying critical technologies and prioritizing investment efforts. Trade studies must be performed on engine concepts examining the affordability, operability, and reliability of each concept, and quantifying the impacts of proposed technologies. These studies can be performed through use of the Technology Impact Forecasting (TIF) method. The Technology Impact

  14. Effectiveness of oxygen enriched hydrogen-HHO gas addition on DI diesel engine performance, emission and combustion characteristics

    National Research Council Canada - National Science Library

    Premkartikkumar S.R; Annamalai K; Pradeepkumar A.R

    2014-01-01

    Nowadays, more researches focus on protecting the environment. Present investigation concern with the effectiveness of Oxygen Enriched hydrogen- HHO gas addition on performance, emission and combustion characteristics of a DI diesel engine...

  15. Role of lubrication oil in particulate emissions from a hydrogen-powered internal combustion engine.

    Science.gov (United States)

    Miller, Arthur L; Stipe, Christopher B; Habjan, Matthew C; Ahlstrand, Gilbert G

    2007-10-01

    Recent studies suggest that trace metals emitted by internal combustion engines are derived mainly from combustion of lubrication oil. This hypothesis was examined by investigation of the formation of particulate matter emitted from an internal combustion engine in the absence of fuel-derived soot. Emissions from a modified CAT 3304 diesel engine fueled with hydrogen gas were characterized. The role of organic carbon and metals from lubrication oil on particle formation was investigated under selected engine conditions. The engine produced exhaust aerosol with log normal-size distributions and particle concentrations between 10(5) and 10(7) cm(-3) with geometric mean diameters from 18 to 31 nm. The particles contained organic carbon, little or no elemental carbon, and a much larger percentage of metals than particles from diesel engines. The maximum total carbon emission rate was estimated at 1.08 g h(-1), which is much lower than the emission rate of the original diesel engine. There was also evidence that less volatile elements, such as iron, self-nucleated to form nanoparticles, some of which survive the coagulation process.

  16. Assessment of engine׳s power budget for hydrogen powered hybrid buoyant aircraft

    Directory of Open Access Journals (Sweden)

    Anwar U. Haque

    2016-03-01

    Full Text Available It is well known that hydrogen has less undesirable exhaust emissions as compared with other types of liquid fuels. It can be used as an alternative fuel for a hybrid buoyant aircraft in which half of the gross takeoff weight is balanced by the aerostatic lift. In the present study, weight advantage of liquid hydrogen as an ideal fuel has been explored for its further utilization in such aircraft. Existing relationships for the estimation of zero lift drag of airship is discussed with special focus on the utilization of such analytical relationships for the aircraft whose fuselage resembles with the hull of an airship. Taking the analytical relationship of aircraft and airship design as a reference, existing relationships for estimation of power budget are systematically re-derived for defined constraints of rate of climb, maximum velocity and takeoff ground roll. It is perceived that when the propulsion sizing for liquid hydrogen is required, then the presented framework for estimation of its power budget will provide a starting point for the analysis. An example for estimation of the power requirement is also presented as a test case.

  17. Application of Hydrogen Assisted Lean Operation to Natural Gas-Fueled Reciprocating Engines (HALO)

    Energy Technology Data Exchange (ETDEWEB)

    Chad Smutzer

    2006-01-01

    Two key challenges facing Natural Gas Engines used for cogeneration purposes are spark plug life and high NOx emissions. Using Hydrogen Assisted Lean Operation (HALO), these two keys issues are simultaneously addressed. HALO operation, as demonstrated in this project, allows stable engine operation to be achieved at ultra-lean (relative air/fuel ratios of 2) conditions, which virtually eliminates NOx production. NOx values of 10 ppm (0.07 g/bhp-hr NO) for 8% (LHV H2/LHV CH4) supplementation at an exhaust O2 level of 10% were demonstrated, which is a 98% NOx emissions reduction compared to the leanest unsupplemented operating condition. Spark ignition energy reduction (which will increase ignition system life) was carried out at an oxygen level of 9%, leading to a NOx emission level of 28 ppm (0.13 g/bhp-hr NO). The spark ignition energy reduction testing found that spark energy could be reduced 22% (from 151 mJ supplied to the coil) with 13% (LHV H2/LHV CH4) hydrogen supplementation, and even further reduced 27% with 17% hydrogen supplementation, with no reportable effect on NOx emissions for these conditions and with stable engine torque output. Another important result is that the combustion duration was shown to be only a function of hydrogen supplementation, not a function of ignition energy (until the ignitability limit was reached). The next logical step leading from these promising results is to see how much the spark energy reduction translates into increase in spark plug life, which may be accomplished by durability testing.

  18. Experimental hydrogen-fueled automotive engine design data-base project. Volume 1. Executive summary report

    Energy Technology Data Exchange (ETDEWEB)

    Swain, M.R.; Adt, R.R. Jr.; Pappas, J.M.

    1983-05-01

    A preliminary hydrogen-fueled automotive piston engine design data-base now exists as a result of a research project at the University of Miami. The effort, which is overviewed here, encompassed the testing of 19 different configurations of an appropriately-modified, 1.6-liter displacement, light-duty automotive piston engine. The design data base includes engine performance and exhaust emissions over the entire load range, generally at a fixed speed (1800 rpm) and best efficiency spark timing. This range was sometimes limited by intake manifold backfiring and lean-limit restrictions; however, effective measures were demonstrated for obviating these problems. High efficiency, competitive specific power, and low emissions were conclusively demonstrated.

  19. The impact of hydrogen-bearing gas to change indexes of car engine in operating conditions

    Directory of Open Access Journals (Sweden)

    Korpach A.

    2016-08-01

    Full Text Available Due to lower oil and petroleum products there is a constant problem of the growing use of alternative fuels. One of the most promising is hydrogen, but its use as a self-fuel is rather difficult, but using as the form of supplements has prospects for widespread use in road transport. In order to establish the effectiveness of its use as a hydrogen-containing gas as a product of the electrolysis of the alkaline solution, a series of tests conducted. Tests were carried out on the car ZAZ–1102 "Tavria", which is equipped with an engine MeMZ–245 with carburetor feed system and electrolyser SuperKit 10, which is powered by the vehicle electrical system. At the same time also used electrolytic League–02. The effect on fuel economy additives hydrogen-containing gas to the air charge is determined when the engine is idling. When using additives 1,34 % interest, from the weight of the fuel, fuel efficiency has increased by 1,9 %.

  20. The Influence of Injection Timing on Performance Characteristics of Diesel Engine Using Jatropha Biodiesel with and without Partial Hydrogenation

    Directory of Open Access Journals (Sweden)

    Rizqon Fajar

    2014-07-01

    Full Text Available Experimental research has been conducted to investigate the effects of blend of hydrogenated and unhydrogenated Jatropha biodiesel with diesel fuel in volume ratio of 30:70 (B30 on combustion characteristics (BSFC, thermal efficiency and smoke emission of single cylinder diesel engine. In this experiment, engine speed was kept constant at 1,500, 2,500, and 3,500 rpm with maximum engine load at BMEP 5 bar and injection timings were varied. Experimental result showed that at engine speed 1,500 rpm, BSFC of B30 hydrogenated and unhydrogenated Jatropha biodiesel were higher than it of diesel fuel at all injection timings (10° to 18° BTDC. At the same condition, partial hydrogenated Jatropha biodiesel showed higher BSFC than unhydrogenated Jatropha biodiesel. However, the difference in BSFC became smaller for all fuels at engine speed 2,500 rpm and 3,500 rpm at all injection timing. Jatropha biodiesel with and without partial hydrogenation tend to have higher thermal efficiency compared with diesel fuel at all engine speed and injection timing. The best injection timings to operate B30 Jatropha biodiesel with and without hydrogenation were 14°, 18° and 24° BTDC at engine speed 1,500, 2,500, and 3,500 rpm respectively. This conclusion was deduced based on the minimum value of BSFC and the maximum value of thermal efficiency. Smoke emissions for all fuels were in the same level for all conditions.

  1. Liquid Acquisition Device Hydrogen Outflow Testing on the Cryogenic Propellant Storage and Transfer Engineering Design Unit

    Science.gov (United States)

    Zimmerli, Greg; Statham, Geoff; Garces, Rachel; Cartagena, Will

    2015-01-01

    As part of the NASA Cryogenic Propellant Storage and Transfer (CPST) Engineering Design Unit (EDU) testing with liquid hydrogen, screen-channel liquid acquisition devices (LADs) were tested during liquid hydrogen outflow from the EDU tank. A stainless steel screen mesh (325x2300 Dutch T will weave) was welded to a rectangular cross-section channel to form the basic LAD channel. Three LAD channels were tested, each having unique variations in the basic design. The LADs fed a common outflow sump at the aft end of the 151 cu. ft. volume aluminum tank, and included a curved section along the aft end and a straight section along the barrel section of the tank. Wet-dry sensors were mounted inside the LAD channels to detect when vapor was ingested into the LADs during outflow. The use of warm helium pressurant during liquid hydrogen outflow, supplied through a diffuser at the top of the tank, always led to early breakdown of the liquid column. When the tank was pressurized through an aft diffuser, resulting in cold helium in the ullage, LAD column hold-times as long as 60 minutes were achieved, which was the longest duration tested. The highest liquid column height at breakdown was 58 cm, which is 23 less than the isothermal bubble-point model value of 75 cm. This paper discusses details of the design, construction, operation and analysis of LAD test data from the CPST EDU liquid hydrogen test.

  2. Engineering Analysis Studies for Preliminary Design of Lightweight Cryogenic Hydrogen Tanks in UAV Applications

    Science.gov (United States)

    Sullivan, Roy M.; Palko, Joseph L.; Tornabene, Robert T.; Bednarcyk, Brett A.; Powers, Lynn M.; Mital, Subodh K.; Smith, Lizalyn M.; Wang, Xiao-Yen J.; Hunter, James E.

    2006-01-01

    A series of engineering analysis studies were conducted to investigate the potential application of nanoclay-enhanced graphite/epoxy composites and polymer cross-linked silica aerogels in cryogenic hydrogen storage tank designs. This assessment focused on the application of these materials in spherical tank designs for unmanned aeronautic vehicles with mission durations of 14 days. Two cryogenic hydrogen tank design concepts were considered: a vacuum-jacketed design and a sandwiched construction with an aerogel insulating core. Analyses included thermal and structural analyses of the tank designs as well as an analysis of hydrogen diffusion to specify the material permeability requirements. The analyses also provided material property targets for the continued development of cross-linked aerogels and nanoclay-enhanced graphite/epoxy composites for cryogenic storage tank applications. The results reveal that a sandwiched construction with an aerogel core is not a viable design solution for a 14-day mission. A vacuum-jacketed design approach was shown to be far superior to an aerogel. Aerogel insulation may be feasible for shorter duration missions. The results also reveal that the application of nanoclay-enhanced graphite/epoxy should be limited to the construction of outer tanks in a vacuum-jacketed design, since a graphite/epoxy inner tank does not provide a significant weight savings over aluminum and since the ability of nanoclay-enhanced graphite/epoxy to limit hydrogen permeation is still in question.

  3. Hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Pier, M.

    1943-02-19

    A transcript is presented of a speech on the history of the development of hydrogenation of coal and tar. Apparently the talk had been accompanied by the showing of photographic slides, but none of the pictures were included with the report. In giving the history, Dr. Pier mentioned the dependence of much of the development of hydrogenation upon previous development in the related areas of ammonia and methanol syntheses, but he also pointed out several ways in which equipment appropriate for hydrogenation differed considerably from that used for ammonia and methanol. Dr. Pier discussed the difficulties encountered with residue processing, design of the reaction ovens, manufacture of ovens and preheaters, heating of reaction mixtures, development of steels, and development of compressor pumps. He described in some detail his own involvement in the development of the process. In addition, he discussed the development of methods of testing gasolines and other fuels. Also he listed some important byproducts of hydrogenation, such as phenols and polycyclic aromatics, and he discussed the formation of iso-octane fuel from the butanes arising from hydrogenation. In connection with several kinds of equipment used in hydrogenation (whose pictures were being shown), Dr. Pier gave some of the design and operating data.

  4. Effect of Hydrogen and Hydrogen Enriched Compressed Natural Gas Induction on the Performance of Rubber Seed Oil Methy Ester Fuelled Common Rail Direct Injection (CRDi Dual Fuel Engines

    Directory of Open Access Journals (Sweden)

    Mallikarjun Bhovi

    2017-06-01

    Full Text Available Renewable fuels are in biodegradable nature and they tender good energy security and foreign exchange savings. In addition they address environmental concerns and socio-economic issues. The present work presents the experimental investigations carried out on the utilization of such renewable fuel combinations for diesel engine applications. For this a single-cylinder four-stroke water cooled direct injection (DI compression ignition (CI engine provided with CMFIS (Conventional Mechanical Fuel Injection System was rightfully converted to operate with CRDi injection systems enabling high pressure injection of Rubber seed oil methyl ester (RuOME in the dual fuel mode with induction of varied gas flow rates of hydrogen and hydrogen enriched CNG (HCNG gas combinations. Experimental investigations showed a considerable improvement in dual fuel engine performance with acceptable brake thermal efficiency and reduced emissions of smoke, hydrocarbon (HC, carbon monoxide (CO and slightly increased nitric oxide (NOx emission levels for increased hydrogen and HCNG flow rates. Further CRDi facilitated dual fuel engine showed improved engine performance compared to CMFIS as the former enabled high pressure (900 bar injection of the RuOME and closer to TDC (Top Dead Centre as well. Combustion parameters such as ignition delay, combustion duration, pressure-crank angle and heat release rates were analyzed and compared with baseline data generated. Combustion analysis showed that the rapid rate of burning of hydrogen and HCNG along with air mixtures increased due to presence of hydrogen in total and in partial combination with CNG which further resulted into higher cylinder pressures and energy release rates. However, sustained research that can provide feasible engine technology operating on such fuels in dual fuel operation can pave the way for continued fossil fuel usage.

  5. Reactor moderator, pressure vessel, and heat rejection system of an open-cycle gas core nuclear rocket concept

    Science.gov (United States)

    Taylor, M. F.; Whitmarsh, C. L., Jr.; Sirocky, P. J., Jr.; Iwanczyke, L. C.

    1973-01-01

    A preliminary design study of a conceptual 6000-megawatt open-cycle gas-core nuclear rocket engine system was made. The engine has a thrust of 196,600 newtons (44,200 lb) and a specific impulse of 4400 seconds. The nuclear fuel is uranium-235 and the propellant is hydrogen. Critical fuel mass was calculated for several reactor configurations. Major components of the reactor (reflector, pressure vessel, and waste heat rejection system) were considered conceptually and were sized.

  6. Laser Transmission Measurements of Soot Extinction Coefficients in the Exhaust Plume of the X-34 60k-lb Thrust Fastrac Rocket Engine

    Science.gov (United States)

    Dobson, C. C.; Eskridge, R. H.; Lee, M. H.

    2000-01-01

    A four-channel laser transmissometer has been used to probe the soot content of the exhaust plume of the X-34 60k-lb thrust Fastrac rocket engine at NASA's Marshall Space Flight Center. The transmission measurements were made at an axial location about equal 1.65 nozzle diameters from the exit plane and are interpreted in terms of homogeneous radial zones to yield extinction coefficients from 0.5-8.4 per meter. The corresponding soot mass density, spatially averaged over the plume cross section, is, for Rayleigh particles, approximately equal to 0.7 micrograms/cubic cm and alternative particle distributions are briefly considered. Absolute plume radiance at the laser wavelength (515 nm) is estimated from the data at approximately equal to 2.200 K equivalent blackbody temperature, and temporal correlations in emission from several spatial locations are noted.

  7. Metabolic engineering of Caldicellulosiruptor bescii yields increased hydrogen production from lignocellulosic biomass

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Minseok [University of Georgia, Athens, GA; Chung, Daehwan [University of Georgia, Athens, GA; Elkins, James G [ORNL; Guss, Adam M [ORNL; Westpheling, Janet [University of Georgia, Athens, GA

    2013-01-01

    Background: Members of the anaerobic thermophilic bacterial genus Caldicellulosiruptor are emerging candidates for consolidated bioprocessing (CBP) because they are capable of efficiently growing on biomass without conventional pretreatment. C. bescii produces primarily lactate, acetate and hydrogen as fermentation products, and while some Caldicellulosiruptor strains produce small amounts of ethanol C. bescii does not, making it an attractive background to examine the effects of metabolic engineering. The recent development of methods for genetic manipulation has set the stage for rational engineering of this genus for improved biofuel production. Here, we report the first targeted gene deletion, the gene encoding lactate dehydrogenase (ldh), for metabolic engineering of a member of this genus. Results: A deletion of the C. bescii L-lactate dehydrogenase gene (ldh) was constructed on a non-replicating plasmid and introduced into the C. bescii chromosome by marker replacement. The resulting strain failed to produce detectable levels of lactate from cellobiose and maltose, instead increasing production of acetate and H2 by 21-34% relative to the wild type and pyrFA parent strains. The same phenotype was observed on a real-world substrate switchgrass (Panicum virgatum). Furthermore, the ldh deletion strain grew to a higher maximum optical density than the wild type on maltose and cellobiose, consistent with the prediction that the mutant would gain additional ATP with increased acetate production. Conclusions: Deletion of ldh in C. bescii is the first use of recently developed genetic methods for metabolic engineering of these bacteria. This deletion resulted in a redirection of electron flow from production of lactate to acetate and hydrogen. New capabilities in metabolic engineering combined with intrinsic utilization of lignocellulosic materials position these organisms to provide a new paradigm for consolidated bioprocessing of fuels and other products from

  8. Hybrid Rocket Technology

    OpenAIRE

    Sankaran Venugopal; K K Rajesh; V. Ramanujachari

    2011-01-01

    With their unique operational characteristics, hybrid rockets can potentially provide safer, lower-cost avenues for spacecraft and missiles than the current solid propellant and liquid propellant systems. Classical hybrids can be throttled for thrust tailoring, perform in-flight motor shutdown and restart. In classical hybrids, the fuel is stored in the form of a solid grain, requiring only half the feed system hardware of liquid bipropellant engines. The commonly used fuels are benign, nonto...

  9. Two-dimensional motions of rockets

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Yoonhwan [School of Electrical Engineering and Computer Sciences (EECS), Seoul National University, San 56-1, Sillim-dong, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Bae, Saebyok [Institute for Gifted Students, Korea Advanced Institute of Science and Technology (KAIST), 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

    2007-01-15

    We analyse the two-dimensional motions of the rockets for various types of rocket thrusts, the air friction and the gravitation by using a suitable representation of the rocket equation and the numerical calculation. The slope shapes of the rocket trajectories are discussed for the three types of rocket engines. Unlike the projectile motions, the descending parts of the trajectories tend to be gentler and straighter slopes than the ascending parts for relatively large launching angles due to the non-vanishing thrusts. We discuss the ranges, the maximum altitudes and the engine performances of the rockets. It seems that the exponential fuel exhaustion can be the most potent engine for the longest and highest flights.0.

  10. Effects of Exhaust Gas Recirculation on Performance and Emission Characteristic of SI Engine using Hydrogen and CNG Blends

    Science.gov (United States)

    Nitnaware, Pravin Tukaram; Suryawanshi, Jiwak G.

    2018-01-01

    This paper shows exhaust gas recirculation (EGR) effects on multi-cylinder bi-fuel SI engine using blends of 0, 5, 10 and 15% hydrogen by energy with CNG. All trials are performed at a speed of 3000, 3500 and 4000 rpm with EGR rate of 0, 5, 10 and 15%, with equal spark timing and injection pressure of 2.6 bar. At specific hydrogen percentage with increase in EGR rate NOx emission reduces drastically and increases with increase in hydrogen addition. Hydrocarbon (HC) and carbon monoxide (CO) emission decreases with increase in speed and hydrogen addition. There is considerable improvement in brake thermal efficiency (BTE) and brake specific energy consumption (BSEC) at 15% EGR rate. At 3000 rpm, 5% EGR rate with 5% hydrogen had shown maximum cylinder pressure. Brake specific fuel consumption (b.s.f.c) increased with increase in EGR rate and decreased with increase in hydrogen addition for all speeds.

  11. Photographic Study of Combustion in a Rocket Engine I : Variation in Combustion of Liquid Oxygen and Gasoline with Seven Methods of Propellant Injection

    Science.gov (United States)

    Bellman, Donald R; Humphrey, Jack C

    1948-01-01

    Motion pictures at camera speeds up to 3000 frames per second were taken of the combustion of liquid oxygen and gasoline in a 100-pound-thrust rocket engine. The engine consisted of thin contour and injection plates clamped between two clear plastic sheets forming a two-dimensional engine with a view of the entire combustion chamber and nozzle. A photographic investigation was made of the effect of seven methods of propellant injection on the uniformity of combustion. From the photographs, it was found that the flame front extended almost to the faces of the injectors with most of the injection methods, all the injection systems resulted in a considerable nonuniformity of combustion, and luminosity rapidly decreased in the divergent part of the nozzle. Pressure vibration records indicated combustion vibrations that approximately corresponded to the resonant frequencies of the length and the thickness of the chamber. The combustion temperature divided by the molecular weight of the combustion gases as determined from the combustion photographs was about 50 to 70 percent of the theoretical value.

  12. Control of the self-oscillation of amplitude of vibration combustion in a liquid-propellant rocket engine by solving the system of equations that describe this regime of combustion

    Science.gov (United States)

    Gotsulenko, V. V.

    2010-07-01

    Periodic solutions of the degenerate system of equations of nonstationary motion of a medium in a liquid-propellant rocket engine were obtained, with the aid of which the possibility of lowering the amplitude of the longitudinal self-oscillations of vibration combustion or their complete removal has been substantiated.

  13. Rocket Propulsion Technology Impact on TSTO Launch System Cost

    National Research Council Canada - National Science Library

    Mossman, Jason

    2001-01-01

    .... This paper reports the methods and results of that study. The reported analysis focused on chemical rocket propulsion using either hydrogen or hydrocarbon fuels, and oxygen or high purity hydrogen peroxide as oxidizers...

  14. Hydrogen.

    Science.gov (United States)

    Bockris, John O'M

    2011-11-30

    The idea of a "Hydrogen Economy" is that carbon containing fuels should be replaced by hydrogen, thus eliminating air pollution and growth of CO₂ in the atmosphere. However, storage of a gas, its transport and reconversion to electricity doubles the cost of H₂ from the electrolyzer. Methanol made with CO₂ from the atmosphere is a zero carbon fuel created from inexhaustible components from the atmosphere. Extensive work on the splitting of water by bacteria shows that if wastes are used as the origin of feed for certain bacteria, the cost for hydrogen becomes lower than any yet known. The first creation of hydrogen and electricity from light was carried out in 1976 by Ohashi et al. at Flinders University in Australia. Improvements in knowledge of the structure of the semiconductor-solution system used in a solar breakdown of water has led to the discovery of surface states which take part in giving rise to hydrogen (Khan). Photoelectrocatalysis made a ten times increase in the efficiency of the photo production of hydrogen from water. The use of two electrode cells; p and n semiconductors respectively, was first introduced by Uosaki in 1978. Most photoanodes decompose during the photoelectrolysis. To avoid this, it has been necessary to create a transparent shield between the semiconductor and its electronic properties and the solution. In this way, 8.5% at 25 °C and 9.5% at 50 °C has been reached in the photo dissociation of water (GaP and InAs) by Kainthla and Barbara Zeleney in 1989. A large consortium has been funded by the US government at the California Institute of Technology under the direction of Nathan Lewis. The decomposition of water by light is the main aim of this group. Whether light will be the origin of the post fossil fuel supply of energy may be questionable, but the maximum program in this direction is likely to come from Cal. Tech.

  15. Base Flow and Heat Transfer Characteristics of a Four-Nozzle Clustered Rocket Engine: Effect of Nozzle Pressure Ratio

    Science.gov (United States)

    Nallasamy, R.; Kandula, M.; Duncil, L.; Schallhorn, P.

    2010-01-01

    The base pressure and heating characteristics of a four-nozzle clustered rocket configuration is studied numerically with the aid of OVERFLOW Navier-Stokes code. A pressure ratio (chamber pressure to freestream static pressure) range of 990 to 5,920 and a freestream Mach number range of 2.5 to 3.5 are studied. The qualitative trends of decreasing base pressure with increasing pressure ratio and increasing base heat flux with increasing pressure ratio are correctly predicted. However, the predictions for base pressure and base heat flux show deviations from the wind tunnel data. The differences in absolute values between the computation and the data are attributed to factors such as perfect gas (thermally and calorically perfect) assumption, turbulence model inaccuracies in the simulation, and lack of grid adaptation.

  16. How Does Rocket Propulsion Work? The most common answer to ...

    Indian Academy of Sciences (India)

    The most common answer to the above question is – hot jet of gas comes out of the nozzle of the rocket engine at high speeds and as a reaction the rocket moves (is propelled) in the opposite direction [1]. But is this answer right? Let us explore what goes on inside a rocket engine and arrive at the right answer. Generally ...

  17. Evaluation of Technical Feasibility of Homogeneous Charge Compression Ignition (HCCI) Engine Fueled with Hydrogen, Natural Gas, and DME

    Energy Technology Data Exchange (ETDEWEB)

    John Pratapas; Daniel Mather; Anton Kozlovsky

    2007-03-31

    The objective of the proposed project was to confirm the feasibility of using blends of hydrogen and natural gas to improve the performance, efficiency, controllability and emissions of a homogeneous charge compression ignition (HCCI) engine. The project team utilized both engine simulation and laboratory testing to evaluate and optimize how blends of hydrogen and natural gas fuel might improve control of HCCI combustion. GTI utilized a state-of-the art single-cylinder engine test platform for the experimental work in the project. The testing was designed to evaluate the feasibility of extending the limits of HCCI engine performance (i.e., stable combustion, high efficiency and low emissions) on natural gas by using blends of natural gas and hydrogen. Early in the project Ricardo provided technical support to GTI as we applied their engine performance simulation program, WAVE, to our HCCI research engine. Modeling support was later provided by Digital Engines, LLC to use their proprietary model to predict peak pressures and temperatures for varying operating parameters included in the Design of Experiments test plan. Digital Engines also provided testing support for the hydrogen and natural gas blends. Prof. David Foster of University of Wisconsin-Madison participated early in the project by providing technical guidance on HCCI engine test plans and modeling requirements. The main purpose of the testing was to quantify the effects of hydrogen addition to natural gas HCCI. Directly comparing straight natural gas with the hydrogen enhanced test points is difficult due to the complexity of HCCI combustion. With the same air flow rate and lambda, the hydrogen enriched fuel mass flow rate is lower than the straight natural gas mass flow rate. However, the energy flow rate is higher for the hydrogen enriched fuel due to hydrogen's significantly greater lower heating value, 120 mJ/kg for hydrogen compared to 45 mJ/kg for natural gas. With these caveats in mind, an

  18. Experimental/Analytical Characterization of the RBCC Rocket-Ejector Mode

    Science.gov (United States)

    Ruf, J. H.; Lehman, M.; Pal, S.; Santoro, R. J.

    2000-01-01

    The experimental/analytical research work described here addresses the rocket-ejector mode (Mach 0-2 operational range) of the RBCC engine. The experimental phase of the program includes studying the mixing and combustion characteristics of the rocket-ejector system utilizing state-of-the-art diagnostic techniques. A two-dimensional variable geometry rocket-ejector system with enhanced optical access was utilized as the experimental platform. The goals of the experimental phase of the research being conducted at Penn State are to: (a) systematically increase the range of rocket-ejector understanding over a wide range of flow/geometry parameters and (b) provide a comprehensive data base for evaluating and anchoring CFD codes. Concurrent with the experimental activities, a CFD code benchmarking effort at Marshall Space Flight Center is also being used to further investigate the RBCC rocket-ejector mode. Experiments involving the single rocket based optically-accessible rocket-ejector system have been conducted for Diffusion and Afterburning (DAB) as well as Simultaneous Mixing and Combustion configurations. For the DAB configuration, air is introduced (direct-connect) or ejected (sea-level static) into a constant area mixer section with a centrally located gaseous oxygen (GO2)/gaseous hydrogen (GH2) rocket combustor. The downstream flowpath for this configuration includes a diffuser, an afterburner and a final converging nozzle. For the SMC configuration, the rocket is centrally located in a slightly divergent duct. For all tested configurations, global measurements of the axial pressure and heat transfer profiles as well as the overall engine thrust were made. Detailed measurements include major species concentration (H2 O2 N2 and H2O) profiles at various mixer locations made using Raman spectroscopy. Complementary CFD calculations of the flowfield at the experimental conditions also provide additional information on the physics of the problem. These calculations

  19. Hydrogen

    Directory of Open Access Journals (Sweden)

    John O’M. Bockris

    2011-11-01

    Full Text Available The idea of a “Hydrogen Economy” is that carbon containing fuels should be replaced by hydrogen, thus eliminating air pollution and growth of CO2 in the atmosphere. However, storage of a gas, its transport and reconversion to electricity doubles the cost of H2 from the electrolyzer. Methanol made with CO2 from the atmosphere is a zero carbon fuel created from inexhaustible components from the atmosphere. Extensive work on the splitting of water by bacteria shows that if wastes are used as the origin of feed for certain bacteria, the cost for hydrogen becomes lower than any yet known. The first creation of hydrogen and electricity from light was carried out in 1976 by Ohashi et al. at Flinders University in Australia. Improvements in knowledge of the structure of the semiconductor-solution system used in a solar breakdown of water has led to the discovery of surface states which take part in giving rise to hydrogen (Khan. Photoelectrocatalysis made a ten times increase in the efficiency of the photo production of hydrogen from water. The use of two electrode cells; p and n semiconductors respectively, was first introduced by Uosaki in 1978. Most photoanodes decompose during the photoelectrolysis. To avoid this, it has been necessary to create a transparent shield between the semiconductor and its electronic properties and the solution. In this way, 8.5% at 25 °C and 9.5% at 50 °C has been reached in the photo dissociation of water (GaP and InAs by Kainthla and Barbara Zeleney in 1989. A large consortium has been funded by the US government at the California Institute of Technology under the direction of Nathan Lewis. The decomposition of water by light is the main aim of this group. Whether light will be the origin of the post fossil fuel supply of energy may be questionable, but the maximum program in this direction is likely to come from Cal. Tech.

  20. Effectiveness of oxygen enriched hydrogen-HHO gas addition on DI diesel engine performance, emission and combustion characteristics

    Directory of Open Access Journals (Sweden)

    Premkartikkumar S.R.

    2014-01-01

    Full Text Available Nowadays, more researches focus on protecting the environment. Present investigation concern with the effectiveness of Oxygen Enriched hydrogen- HHO gas addition on performance, emission and combustion characteristics of a DI diesel engine. Here the Oxygen Enriched hydrogen-HHO gas was produced by the process of water electrolysis. When potential difference is applied across the anode and cathode electrodes of the electrolyzer, water is transmuted into Oxygen Enriched hydrogen-HHO gas. The produced gas was aspirated into the cylinder along with intake air at the flow rates of 1 lpm and 3.3 lpm. The results show that when Oxygen Enriched hydrogen-HHO gas was inducted, the brake thermal efficiency of the engine increased by 11.06%, Carbon monoxide decreased by 15.38%, Unburned hydrocarbon decreased by 18.18%, Carbon dioxide increased by 6.06%, however, the NOX emission increased by 11.19%.

  1. Rocket Tablet,

    Science.gov (United States)

    1984-09-12

    the railway platform filled with sand, consumed by a great wave of emotion, looking at the soldiers and waving tearful farewells to them as well as...many matters awaiting me, how can I not be anxious?" Li Fuze rose and said farewell and Li Juemin insisted on -sending him off. These two comrades-in...front of the .? tombstone were the wife of the hero and several hundred solders; an entire rocket troop mourned the hero.... ...... from today on no

  2. Evaluation of Technical Feasibility of Homogeneous Charge Compression Ignition (HCCI) Engine Fueled with Hydrogen, Natural Gas, and DME

    Energy Technology Data Exchange (ETDEWEB)

    Pratapas, John; Mather, Daniel; Kozlovsky, Anton

    2013-03-31

    The objective of the proposed project was to confirm the feasibility of using blends of hydrogen and natural gas to improve the performance, efficiency, controllability and emissions of a homogeneous charge compression ignition (HCCI) engine. The project team utilized both engine simulation and laboratory testing to evaluate and optimize how blends of hydrogen and natural gas fuel might improve control of HCCI combustion. GTI utilized a state-of-the art single-cylinder engine test platform for the experimental work in the project. The testing was designed to evaluate the feasibility of extending the limits of HCCI engine performance (i.e., stable combustion, high efficiency and low emissions) on natural gas by using blends of natural gas and hydrogen. Early in the project Ricardo provided technical support to GTI as we applied their engine performance simulation program, WAVE, to our HCCI research engine. Modeling support was later provided by Digital Engines, LLC to use their proprietary model to predict peak pressures and temperatures for varying operating parameters included in the Design of Experiments test plan. Digital Engines also provided testing support for the hydrogen and natural gas blends. Prof. David Foster of University of Wisconsin-Madison participated early in the project by providing technical guidance on HCCI engine test plans and modeling requirements. The main purpose of the testing was to quantify the effects of hydrogen addition to natural gas HCCI. Directly comparing straight natural gas with the hydrogen enhanced test points is difficult due to the complexity of HCCI combustion. With the same air flow rate and lambda, the hydrogen enriched fuel mass flow rate is lower than the straight natural gas mass flow rate. However, the energy flow rate is higher for the hydrogen enriched fuel due to hydrogen’s significantly greater lower heating value, 120 mJ/kg for hydrogen compared to 45 mJ/kg for natural gas. With these caveats in mind, an

  3. Experimental Evaluation of SI Engine Operation Supplemented by Hydrogen Rich Gas from a Compact Plasma Boosted Reformer

    Energy Technology Data Exchange (ETDEWEB)

    J. B. Green, Jr.; N. Domingo; J. M. E. Storey; R.M. Wagner; J.S. Armfield; L. Bromberg; D. R. Cohn; A. Rabinovich; N. Alexeev

    2000-06-19

    It is well known that hydrogen addition to spark-ignited (SI) engines can reduce exhaust emissions and increase efficiency. Micro plasmatron fuel converters can be used for onboard generation of hydrogen-rich gas by partial oxidation of a wide range of fuels. These plasma-boosted microreformers are compact, rugged, and provide rapid response. With hydrogen supplement to the main fuel, SI engines can run very lean resulting in a large reduction in nitrogen oxides (NO x ) emissions relative to stoichiometric combustion without a catalytic converter. This paper presents experimental results from a microplasmatron fuel converter operating under variable oxygen to carbon ratios. Tests have also been carried out to evaluate the effect of the addition of a microplasmatron fuel converter generated gas in a 1995 2.3-L four-cylinder SI production engine. The tests were performed with and without hydrogen-rich gas produced by the plasma boosted fuel converter with gasoline. A one hundred fold reduction in NO x due to very lean operation was obtained under certain conditions. An advantage of onboard plasma-boosted generation of hydrogen-rich gas is that it is used only when required and can be readily turned on and off. Substantial NO x reduction should also be obtainable by heavy exhaust gas recirculation (EGR) facilitated by use of hydrogen-rich gas with stoichiometric operation.

  4. Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development & Performance Analysis

    Science.gov (United States)

    Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan

    2014-01-01

    ATA-002 Technical Team has successfully designed, developed, tested and assessed the SLS Pathfinder propulsion systems for the Main Base Heating Test Program. Major Outcomes of the Pathfinder Test Program: Reach 90% of full-scale chamber pressure Achieved all engine/motor design parameter requirements Reach steady plume flow behavior in less than 35 msec Steady chamber pressure for 60 to 100 msec during engine/motor operation Similar model engine/motor performance to full-scale SLS system Mitigated nozzle throat and combustor thermal erosion Test data shows good agreement with numerical prediction codes Next phase of the ATA-002 Test Program Design & development of the SLS OML for the Main Base Heating Test Tweak BSRM design to optimize performance Tweak CS-REM design to increase robustness MSFC Aerosciences and CUBRC have the capability to develop sub-scale propulsion systems to meet desired performance requirements for short-duration testing.

  5. SAFE Testing Nuclear Rockets Economically

    Science.gov (United States)

    Howe, Steven D.; Travis, Bryan; Zerkle, David K.

    2003-01-01

    Several studies over the past few decades have recognized the need for advanced propulsion to explore the solar system. As early as the 1960s, Werner Von Braun and others recognized the need for a nuclear rocket for sending humans to Mars. The great distances, the intense radiation levels, and the physiological response to zero-gravity all supported the concept of using a nuclear rocket to decrease mission time. These same needs have been recognized in later studies, especially in the Space Exploration Initiative in 1989. One of the key questions that has arisen in later studies, however, is the ability to test a nuclear rocket engine in the current societal environment. Unlike the Rover/NERVA programs in the 1960s, the rocket exhaust can no longer be vented to the open atmosphere. As a consequence, previous studies have examined the feasibility of building a large-scale version of the Nuclear Furnace Scrubber that was demonstrated in 1971. We have investigated an alternative that would deposit the rocket exhaust along with any entrained fission products directly into the ground. The Subsurface Active Filtering of Exhaust, or SAFE, concept would allow variable sized engines to be tested for long times at a modest expense. A system overview, results of preliminary calculations, and cost estimates of proof of concept demonstrations are presented. The results indicate that a nuclear rocket could be tested at the Nevada Test Site for under $20 M.

  6. Performance, Efficiency, and Emissions Characterization of Reciprocating Internal Combustion Engines Fueled with Hydrogen/Natural Gas Blends

    Energy Technology Data Exchange (ETDEWEB)

    Kirby S. Chapman; Amar Patil

    2007-06-30

    Hydrogen is an attractive fuel source not only because it is abundant and renewable but also because it produces almost zero regulated emissions. Internal combustion engines fueled by compressed natural gas (CNG) are operated throughout a variety of industries in a number of mobile and stationary applications. While CNG engines offer many advantages over conventional gasoline and diesel combustion engines, CNG engine performance can be substantially improved in the lean operating region. Lean operation has a number of benefits, the most notable of which is reduced emissions. However, the extremely low flame propagation velocities of CNG greatly restrict the lean operating limits of CNG engines. Hydrogen, however, has a high flame speed and a wide operating limit that extends into the lean region. The addition of hydrogen to a CNG engine makes it a viable and economical method to significantly extend the lean operating limit and thereby improve performance and reduce emissions. Drawbacks of hydrogen as a fuel source, however, include lower power density due to a lower heating value per unit volume as compared to CNG, and susceptibility to pre-ignition and engine knock due to wide flammability limits and low minimum ignition energy. Combining hydrogen with CNG, however, overcomes the drawbacks inherent in each fuel type. Objectives of the current study were to evaluate the feasibility of using blends of hydrogen and natural gas as a fuel for conventional natural gas engines. The experiment and data analysis included evaluation of engine performance, efficiency, and emissions along with detailed in-cylinder measurements of key physical parameters. This provided a detailed knowledge base of the impact of using hydrogen/natural gas blends. A four-stroke, 4.2 L, V-6 naturally aspirated natural gas engine coupled to an eddy current dynamometer was used to measure the impact of hydrogen/natural gas blends on performance, thermodynamic efficiency and exhaust gas emissions

  7. An Experimental Investigation on Performance and Emissions of a Single Cylinder D.I Diesel Engine with Manifold Hydrogen Induction

    Directory of Open Access Journals (Sweden)

    Haroun A.K. Shahad

    2017-05-01

    Full Text Available Hydrogen is a clean fuel for internal combustion engines as it produces only water vapor and nitrogen oxides when it burns. In this research, hydrogen is used as a blending fuel with diesel to reduce pollutants emission and to improve performance. It is inducted in the inlet manifold, (continuous manifold induction, which is of a single cylinder, four stroke, direct injection, variable compression ratio water cold diesel engine, type (Kirloskar. This technique of hydrogen blending is selected because of its simplicity and low cost. Hydrogen blending is built on the basis of energy replacement. A special electronic unit is designed and fabricated to control hydrogen blending ratio. The maximum achieved ratio is 30% of input energy and beyond that the engine operation becomes unsatisfactory. Tests are done with 17.5 compression ratio and 1500 rpm. The brake specific fuel consumption is reduced by 29% and the engine thermal efficiency increased by 16% at these operating conditions. The pollutant emissions of carbon oxides, UHC, and smoke opacity are dramatically decreased by 19.5%, 13%,and 45% respectively while NOx emission increased by 10%.

  8. The Thermal State Computational Research of the Low-Thrust Oxygen-Methane Gaseous-Propellant Rocket Engine in the Pulse Mode of Operation

    Directory of Open Access Journals (Sweden)

    O. A. Vorozheeva

    2014-01-01

    Full Text Available Currently promising development direction of space propulsion engineering is to use, as spacecraft controls, low-thrust rocket engines (RDTM on clean fuels, such as oxygen-methane. Modern RDTM are characterized by a lack regenerative cooling and pulse mode of operation, during which there is accumulation of heat energy to lead to the high thermal stress of RDTM structural elements. To get an idea about the thermal state of its elements, which further will reduce the number of fire tests is therefore necessary in the development phase of a new product. Accordingly, the aim of this work is the mathematical modeling and computational study of the thermal state of gaseous oxygen-methane propellant RDMT operating in pulse mode.In this paper we consider a model RDTM working on gaseous propellants oxygen-methane in pulse mode.To calculate the temperature field of the chamber wall of model RDMT under consideration is used the mathematical model of non-stationary heat conduction in a two-dimensional axisymmetric formulation that takes into account both the axial heat leakages and the nonstationary processes occurring inside the chamber during pulse operation of RDMT.As a result of numerical study of the thermal state of model RDMT, are obtained the temperature fields during engine operation based on convective, conductive, and radiative mechanisms of heat transfer from the combustion products to the wall.It is shown that the elements of flanges of combustion chamber of model RDMT act as heat sinks structural elements. Temperatures in the wall of the combustion chamber during the engine mode of operation are considered relatively low.Raised temperatures can also occur in the mixing head in the feeding area of the oxidant into the combustion chamber.During engine operation in the area forming the critical section, there is an intensive heating of a wall, which can result in its melting, which in turn will increase the minimum nozzle throat area and hence

  9. Modeling Potential Carbon Monoxide Exposure Due to Operation of a Major Rocket Engine Altitude Test Facility Using Computational Fluid Dynamics

    Science.gov (United States)

    Blotzer, Michael J.; Woods, Jody L.

    2009-01-01

    This viewgraph presentation reviews computational fluid dynamics as a tool for modelling the dispersion of carbon monoxide at the Stennis Space Center's A3 Test Stand. The contents include: 1) Constellation Program; 2) Constellation Launch Vehicles; 3) J2X Engine; 4) A-3 Test Stand; 5) Chemical Steam Generators; 6) Emission Estimates; 7) Located in Existing Test Complex; 8) Computational Fluid Dynamics; 9) Computational Tools; 10) CO Modeling; 11) CO Model results; and 12) Next steps.

  10. V-2 Rocket at White Sands

    Science.gov (United States)

    1946-01-01

    A V-2 rocket takes flight at White Sands, New Mexico, in 1946. The German engineers and scientists who developed the V-2 came to the United States at the end of World War II and continued rocket testing under the direction of the U. S. Army, launching more than sixty V-2s.

  11. Synergistic Interlayer and Defect Engineering in VS2 Nanosheets toward Efficient Electrocatalytic Hydrogen Evolution Reaction

    KAUST Repository

    Zhang, Junjun

    2017-12-27

    A simple one-pot solvothermal method is reported to synthesize VS2 nanosheets featuring rich defects and an expanded (001) interlayer spacing as large as 1.00 nm, which is a ≈74% expansion as relative to that (0.575 nm) of the pristine counterpart. The interlayer-expanded VS2 nanosheets show extraordinary kinetic metrics for electrocatalytic hydrogen evolution reaction (HER), exhibiting a low overpotential of 43 mV at a geometric current density of 10 mA cm-2 , a small Tafel slope of 36 mV dec-1 , and long-term stability of 60 h without any current fading. The performance is much better than that of the pristine VS2 with a normal interlayer spacing, and even comparable to that of the commercial Pt/C electrocatalyst. The outstanding electrocatalytic activity is attributed to the expanded interlayer distance and the generated rich defects. Increased numbers of exposed active sites and modified electronic structures are achieved, resulting in an optimal free energy of hydrogen adsorption (∆GH ) from density functional theory calculations. This work opens up a new door for developing transition-metal dichalcogenide nanosheets as high active HER electrocatalysts by interlayer and defect engineering.

  12. Low-thrust rocket trajectories

    Energy Technology Data Exchange (ETDEWEB)

    Keaton, P.W.

    1987-03-01

    The development of low-thrust propulsion systems to complement chemical propulsion systems will greatly enhance the evolution of future space programs. Two advantages of low-thrust rockets are stressed: first, in a strong gravitational field, such as occurs near the Earth, freighter missions with low-thrust engines require one-tenth as much propellant as do chemical engines. Second, in a weak gravitational field, such as occurs in the region between Venus and Mars, low-thrust rockets are faster than chemical rockets with comparable propellant mass. The purpose here is to address the physics of low-thrust trajectories and to interpret the results with two simple models. Analytic analyses are used where possible - otherwise, the results of numerical calculations are presented in graphs. The author has attempted to make this a self-contained report.

  13. Low-thrust rocket trajectories

    Energy Technology Data Exchange (ETDEWEB)

    Keaton, P.W.

    1986-01-01

    The development of low-thrust propulsion systems to complement chemical propulsion systems will greatly enhance the evolution of future space programs. Two advantages of low-thrust rockets are stressed: first, in a strong gravitational field, such as occurs near the Earth, freighter missions with low-thrust engines require one-tenth as much propellant as do chemical engines. Second, in a weak gravitational field, such as occurs in the region between Venus and Mars, low-thrust rockets are faster than chemical rockets with comparable propellant mass. The purpose here is to address the physics of low-thrust trajectories and to interpret the results with two simple models. Analytic analyses are used where possible - otherwise, the results of numerical calculations are presented in graphs. The author has attempted to make this a self-contained report. 57 refs., 10 figs.

  14. Effect of hydrogen on ethanol-biodiesel blend on performance and emission characteristics of a direct injection diesel engine.

    Science.gov (United States)

    Parthasarathy, M; Isaac JoshuaRamesh Lalvani, J; Dhinesh, B; Annamalai, K

    2016-12-01

    Environment issue is a principle driving force which has led to a considerable effort to develop and introduce alternative fuels for transportation. India has large potential for production of biofuels like biodiesel from vegetable seeds. Use of biodiesel namely, tamanu methyl ester (TME) in unmodified diesel engines leads to low thermal Efficiency and high smoke emission. To encounter this problem hydrogen was inducted by a port fueled injection system. Hydrogen is considered to be low polluting fuel and is the most promising among alternative fuel. Its clean burning characteristic and better performance attract more interest compared to other fuels. It was more active in reducing smoke emission in biodiesel. A main drawback with hydrogen fuel is the increased NO x emission. To reduce NO x emission, TME-ethanol blends were used in various proportions. After a keen study, it was observed that ethanol can be blended with biodiesel up to 30% in unmodified diesel engine. The present work deals with the experimental study of performance and emission characteristic of the DI diesel engine using hydrogen and TME-ethanol blends. Hydrogen and TME-ethanol blend was used to improve the brake thermal efficiency and reduction in CO, NO x and smoke emissions. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Rocket + Science = Dialogue

    Science.gov (United States)

    Morris,Bruce; Sullivan, Greg; Burkey, Martin

    2010-01-01

    It's a cliche that rocket engineers and space scientists don t see eye-to-eye. That goes double for rocket engineers working on human spaceflight and scientists working on space telescopes and planetary probes. They work fundamentally different problems but often feel that they are competing for the same pot of money. Put the two groups together for a weekend, and the results could be unscientific or perhaps combustible. Fortunately, that wasn't the case when NASA put heavy lift launch vehicle designers together with astronomers and planetary scientists for two weekend workshops in 2008. The goal was to bring the top people from both groups together to see how the mass and volume capabilities of NASA's Ares V heavy lift launch vehicle could benefit the science community. Ares V is part of NASA's Constellation Program for resuming human exploration beyond low Earth orbit, starting with missions to the Moon. In the current mission scenario, Ares V launches a lunar lander into Earth orbit. A smaller Ares I rocket launches the Orion crew vehicle with up to four astronauts. Orion docks with the lander, attached to the Ares V Earth departure stage. The stage fires its engine to send the mated spacecraft to the Moon. Standing 360 feet high and weighing 7.4 million pounds, NASA's new heavy lifter will be bigger than the 1960s-era Saturn V. It can launch almost 60 percent more payload to translunar insertion together with the Ares I and 35 percent more mass to low Earth orbit than the Saturn V. This super-sized capability is, in short, designed to send more people to more places to do more things than the six Apollo missions.

  16. Simulation and Empirical Studies of the Commercial SI Engine Performance and Its Emission Levels When Running on a CNG and Hydrogen Blend

    Directory of Open Access Journals (Sweden)

    Rafaa Saaidia

    2017-12-01

    Full Text Available This article is a report on a simulation based on Computational Fluid Dynamics (CFD and an empirical investigation of in-cylinder flow characteristics, In addition, it assesses the performance and emission levels of a commercial-spark ignited engine running on a CNG and Hydrogen blend in different ratios. The main objective was to determine the optimum hydrogen ratio that would yield the best brake torque and release the least polluting gases. The in-cylinder flow velocity and turbulence aspects were investigated during the intake stroke in order to analyze the intake flow behavior. To reach this goal, a 3D CFD code was adopted. For various engine speeds were investigated for gasoline, CNG and hydrogen and CNG blend (HCNG fueled engines via external mixtures. The variation of brake torque (BT, NOX and CO emissions. A series of tests were conducted on the engine within the speed range of 1000 to 5000 rpm. For this purpose, a commercial Hyundai Sonata S.I engine was modified to operate with a blend of CNG and Hydrogen in different ratios. The experiments attempted to determine the optimum allowable hydrogen ratio with CNG for normal engine operation. The engine performance and the emission levels were also analyzed. At the engine speed of 4200 rpm, the results revealed that beyond a ratio of 50% of the volume of hydrogen added to CNG a backfire phenomenon appeared. Below this ratio (0~40% of the hydrogen volume, the CNG and Hydrogen blend seemed to be beneficial for the engine performance and for curtailing the emission level. However, at low engine speeds, the NOX concentration increased simultaneously with hydrogen content. In contrast, at high engine speeds, the NOX concentration decreased to its lowest level compared to that reached with gasoline as a running fuel. The concentration levels of HC, CO2, and CO decreased with the increase of hydrogen percentage.

  17. Filtration of chlorine and hydrogen chloride gas by engineered UiO-66-NH2metal-organic framework.

    Science.gov (United States)

    Browe, Matthew A; Napolitano, Amedeo; DeCoste, Jared B; Peterson, Gregory W

    2017-06-15

    Chlorine (Cl 2 ) and hydrogen chloride (HCl) are heavily utilized industrial chemicals that present significant respiratory health risks. The metal-organic framework UiO-66-NH 2 has shown an unprecedented ability in powder form to remove chlorine gas. Here, we engineered UiO-66-NH 2 into 20×40 mesh granules and evaluated their ability to remove chlorine and hydrogen chloride gas challenges. The exposed materials were characterized with nitrogen isotherms, powder X-ray diffraction, and attenuated total reflectance - Fourier transform infrared spectroscopy. Breakthrough results revealed that UiO-66-NH 2 sorption of chlorine and hydrogen chloride met or exceeded sorption of state-of-the-art metal-impregnated activated carbon materials on a mass and volume basis in engineered form. Published by Elsevier B.V.

  18. Anion Engineering on Free-Standing Two-Dimensional MoS2 Nanosheets toward Hydrogen Evolution.

    Science.gov (United States)

    Liu, Qilong; Liu, Qiangchun; Kong, Xiangkai

    2017-10-02

    On the basis of theoretical predictions, nitrogen was designed and incorporated into free-standing two-dimensional MoS2 nanosheets. Both the amount of electrochemical active sites on the surface and its intrinsic conductivity could be significantly increased as a result of anion engineering, which can extremely improve the electrocatalytic kinetics toward hydrogen evolution.

  19. Metabolic Engineering and Modeling of Metabolic Pathways to Improve Hydrogen Production by Photosynthetic Bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Jiao, Y. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Navid, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-12-19

    traits act as the biocatalysts of the process designed to both enhance the system efficiency of CO2 fixation and the net hydrogen production rate. Additionally we applied metabolic engineering approaches guided by computational modeling for the chosen model microorganisms to enable efficient hydrogen production.

  20. A new high strength alloy for hydrogen fueled propulsion systems

    Science.gov (United States)

    Mcpherson, W. B.

    1986-01-01

    This paper describes the development of a high-strength alloy (1241 MPa ultimate and 1103 MPa yield, with little or no degradation in hydrogen) for application in advanced hydrogen-fueled rocket engines. Various compositions of the Fe-Ni-Co-Cr system with elemental additions of Cb, Ti and Al are discussed. After processing, notched tensile specimens were tested in 34.5-MPa hydrogen at room temperature, as the main screening test. The H2/air notch tensile ratio was used as the selection/rejection criterion. The most promising alloys are discussed.

  1. Laser diagnostics for small rockets

    Science.gov (United States)

    Zupanc, Frank J.; Degroot, Wilhelmus A.

    1993-11-01

    Two nonintrusive flowfield diagnostics based on spectrally-resolved elastic (Rayleigh) and inelastic (Raman) laser light scattering were developed for obtaining local flowfield measurements in low-thrust gaseous H2/O2 rocket engines. The objective is to provide an improved understanding of phenomena occurring in small chemical rockets in order to facilitate the development and validation of advanced computational fluid dynamics (CFD) models for analyzing engine performance. The laser Raman scattering diagnostic was developed to measure major polyatomic species number densities and rotational temperatures in the high-density flowfield region extending from the injector through the chamber throat. Initial application of the Raman scattering diagnostic provided O2 number density and rotational temperature measurements in the exit plane of a low area-ratio nozzle and in the combustion chamber of a two-dimensional, optically-accessible rocket engine. In the low-density nozzle exit plane region where the Raman signal is too weak, a Doppler-resolved laser Rayleigh scattering diagnostic was developed to obtain axial and radial mean gas velocities, and in certain cases, H2O translational temperature and number density. The results from these measurements were compared with theoretical predictions from the RPLUS CFD code for analyzing rocket engine performance. Initial conclusions indicate that a detailed and rigorous modeling of the injector is required in order to make direct comparisons between laser diagnostic measurements and CFD predictions at the local level.

  2. Liquid propellant rocket combustion instability

    Science.gov (United States)

    Harrje, D. T.

    1972-01-01

    The solution of problems of combustion instability for more effective communication between the various workers in this field is considered. The extent of combustion instability problems in liquid propellant rocket engines and recommendations for their solution are discussed. The most significant developments, both theoretical and experimental, are presented, with emphasis on fundamental principles and relationships between alternative approaches.

  3. Thermodynamic properties and theoretical rocket performance of hydrogen to 100,000 K and 1.01325 x 10 to the 8th power N/sq m

    Science.gov (United States)

    Patch, R. W.

    1971-01-01

    The composition and thermodynamic properties were calculated for 100 to 110,000 K and 1.01325 x 10 to the 2nd power to 1.01325 x 10 to the 8th power N/sq m for chemical equilibrium in the Debye-Huckel and ideal-gas approximations. Quantities obtained were the concentrations of hydrogen atoms, protons, free electrons, hydrogen molecules, negative hydrogen ions, hydrogen diatomic molecular ions, and hydrogen triatomic molecular ions, and the enthalpy, entropy, average molecular weight, specific heat at constant pressure, density, and isentropic exponent. Electronically excited states of H and H2 were included. Choked, isentropic, one-dimensional nozzle flow with shifting chemical equilibrium was calculated to the Debye-Huckel and ideal-gas approximations for stagnation temperatures from 2500 to 100,000 K. The mass flow per unit throat area and the sonic flow factor were obtained. The pressure ratio, temperature, velocity, and ideal and vacuum specific impulses at the throat and for pressure ratios as low as 0.000001 downstream were found. For high temperatures at pressures approaching 1.01325 x 10 to the 8th power N/sq m, the ideal-gas approximation was found to be inadequate for calculations of composition, precise thermodynamic properties, and precise nozzle flow. The greatest discrepancy in nozzle flow occurred in the exit temperature, which was as much as 21 percent higher when the Debye-Huckel approximation was used.

  4. Numerical study on the combustion characteristics of a fuel-centered pintle injector for methane rocket engines

    Science.gov (United States)

    Son, Min; Radhakrishnan, Kanmaniraja; Yoon, Youngbin; Koo, Jaye

    2017-06-01

    A pintle injector is a movable injector capable of controlling injection area and velocities. Although pintle injectors are not a new concept, they have become more notable due to new applications such as planet landers and low-cost engines. However, there has been little consistent research on pintle injectors because they have many design variations and mechanisms. In particular, simulation studies are required for bipropellant applications. In this study, combustion simulation was conducted using methane and oxygen to determine the effects of injection condition and geometries upon combustion characteristics. Steady and two-dimensional axisymmetric conditions were assumed and a 6-step Jones-Lindstedt mechanism with an eddy-dissipation concept model was used for turbulent kinetic reaction. As a result, the results with wide flame angles showed good combustion performances with a large recirculation under the pintle tip. Under lower mass flow-rate conditions, the combustion performance got worse with lower flame angles. To solve this problem, decreasing the pintle opening distance was very effective and the flame angle recovered. In addition, a specific recirculation zone was observed near the post, suggesting that proper design of the post could increase the combustion performance, while the geometry without a recirculation zone had the poor performance.

  5. Development and Performance of the 10 kN Hybrid Rocket Motor for the Stratos II Sounding Rocket

    NARCIS (Netherlands)

    Werner, R.M.; Knop, T.R.; Wink, J; Ehlen, J; Huijsman, R; Powell, S; Florea, R.; Wieling, W; Cervone, A.; Zandbergen, B.T.C.

    2016-01-01

    This paper presents the development work of the 10 kN hybrid rocket motor DHX-200 Aurora. The DHX-200 Aurora was developed by Delft Aerospace Rocket Engineering (DARE) to power the Stratos II and Stratos II+ sounding rocket, with the later one being launched in October 2015. Stratos II and Stratos

  6. YMCA ROCKET RAMPAGE! SUMMER CAMP

    National Research Council Canada - National Science Library

    Anonymous

    2014-01-01

    ... & Controls, sponsored the Rocket Rampagel summer camp at the YMCA in Eklton MD. On day 1, campers took Rockets 101, constructing balloon rockets and straw rockets, followed by racket manufacturing, where campers made rocket "propellant" on day 2...

  7. [Solid state isotope hydrogen exchange for deuterium and tritium in human gene-engineered insulin].

    Science.gov (United States)

    Zolotarev, Yu A; Dadayan, A K; Kozik, V S; Gasanov, E V; Nazimov, I V; Ziganshin, R Kh; Vaskovsky, B V; Murashov, A N; Ksenofontov, A L; Haribin, O N; Nikolaev, E N; Myasoedov, N F

    2014-01-01

    The reaction of high temperature solid state catalytic isotope exchange in peptides and proteins under the action of catalyst-activated spillover hydrogen was studied. The reaction of human gene-engineered insulin with deuterium and tritium was conducted at 120-140° C to produce insulin samples containing 2-6 hydrogen isotope atoms. To determine the distribution of the isotope label over tritium-labeled insulin's amino acid residues, oxidation of the S-S bonds of insulin by performic acid was performed and polypeptide chains isolated; then their acid hydrolysis, amino acid analysis and liquid scintillation counts of tritium in the amino acids were conducted. The isotope label was shown to be incorporated in all amino acids of the protein, with the peptide fragment FVNQHLCGSHLVE of the insulin β-chain showing the largest incorporation. About 45% of the total protein isotope label was incorporated in His5 and His10 of this fragment. For the analysis of isotope label distribution in labeled insulin's peptide fragments, the recovery of the S-S bonds by mercaptoethanol, the enzymatic hydrolysis by glutamyl endopeptidase from Bacillus intermedius and HPLC division of the resulting peptides were carried out. Attribution of the peptide fragments formed due to hydrolysis at the Glu-X bond in the β-chain was accomplished by mass spectrometry. Mass spectrometry analysis data of the deuterium-labeled insulin samples' isotopomeric composition showed that the studied solid state isotope exchange reaction equally involved all the protein molecules. Biological studying of tritium-labeled insulin showed its physiological activity to be completely retained.

  8. New vistas in the determination of hydrogen in aerospace engine metal alloys

    Science.gov (United States)

    Danford, M. D.

    1986-01-01

    The application of diffusion theory to the analysis of hydrogen desorption data has been studied. From these analyses, important information concerning hydrogen solubilities and the nature of the hydrogen distributions in the metal has been obtained. Two nickel base alloys, Rene' 41 and Waspaloy, and one ferrous alloy, 4340 steel, were studied in this work. For the nickel base alloys, it was found that the hydrogen distributions after electrolytic charging conformed closely to those which would be predicted by diffusion theory. The hydrogen distributions in electrolytically charged 4340 steel, on the other hand, were essentially uniform in nature, which would not be predicted by diffusion theory. Finally, it has been found that the hydrogen desorption is completely explained by the nature of the hydrogen distribution in the metal, and that the 'fast' hydrogen is not due to surface and subsurface hydride formation, as was originally proposed.

  9. Meeting Cathala-Letort named: the challenges of the processes engineering facing the hydrogen-energy; Journee Cathala-Letort intitulee: les defis du genie des procedes face a l'hydrogene-energie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This document provides the presentations proposed during the day Cathala-Letort on the challenges of the processes engineering facing the hydrogen-energy. In the context of the greenhouse effect increase and the fossil energies resources decrease, it brings information on researches on hydrogen technologies, carbon dioxide sequestration, hydrogen supply, production, storage and distribution and the thermo-chemical cycles. (A.L.B.)

  10. Hydrogen Recovery System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Liquid hydrogen is used extensively by NASA to support cryogenic rocket testing. In addition, there are many commercial applications in which delivery and use of...

  11. Hydrogen Recovery System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Rocket test operations at NASA Stennis Space Center (SSC) result in substantial quantities of hydrogen gas that is flared from the facility and helium gas that is...

  12. Liquid hydrogen: back to basics

    Energy Technology Data Exchange (ETDEWEB)

    Sherif, S.A. [Dept. of Mechanical and Aerospace Engineering, Univ. of Florida, Florida (United States)

    2009-07-01

    'Full text': Liquid hydrogen is primarily used as a rocket fuel and is predestined for supersonic and hypersonic space vehicles to a large extent because it has the lowest boiling point density and the highest specific thrust of any known fuel. Its favorable characteristics include its high heating value per unit mass, its wide ignition range in hydrogen/oxygen or air mixtures, as well as its large flame speed and cooling capacity due to its high specific heat which permits very effective engine cooling and cooling the critical parts of the outer skin. Liquid hydrogen has some other important uses such as in high-energy nuclear physics and bubble chambers. The transport of hydrogen is vastly more economical when it is in liquid form even though cryogenic refrigeration and special Dewar vessels are required. Although liquid hydrogen can provide a lot of advantages, its uses are restricted in part because liquefying hydrogen by existing conventional methods consumes a large amount of energy (around 30% of its heating value). Liquefying 1 kg of hydrogen in a medium-size plant requires 10 to 13 kWh of electric energy. In addition, boil-off losses associated with the storage, transportation, and handling of liquid hydrogen can consume up to 40% of its available combustion energy. It is therefore important to search for ways that can improve the efficiency of the liquefiers and diminish the boil-off losses. This lecture gives an overview of the main issues associated with the production, storage, and handling of liquid hydrogen. Some discussion of promising ways of hydrogen liquefaction will also be presented. (author)

  13. Effect of hydrogen-diesel combustion on the performance and combustion parameters of a dual fuelled diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Bose, P.K.; Banerjee, Rahul; Deb, Madhujit [Mechanical Engineering Department, National Institute of Technology, Agartala, Tripura-799055 (India)

    2013-07-01

    Petroleum crude is expected to remain main source of transport fuels at least for the next 20 to 30 years. The petroleum crude reserves however, are declining and consumption of transport fuels particularly in the developing countries is increasing at high rates. Severe shortage of liquid fuels derived from petroleum may be faced in the second half of this century. In this paper, experiments are performed in a fur stroke, single cylinder, compression ignition diesel engine with dual fuel mode. Diesel and hydrogen are used as pilot liquid and primary gaseous fuel, respectively. The objective of this study is to find out the effects on combustion and performance parameters observed at diesel hydrogen fuel mixture for all the different loadings (2kg,4kg,6kg,8kg,10kg and 12kg) in the engine.

  14. Response surface methodology for process parameter optimization of hydrogen yield by the metabolically engineered strain Escherichia coli DJT135.

    Science.gov (United States)

    Ghosh, Dipankar; Hallenbeck, Patrick C

    2010-03-01

    Metabolically engineered microbial strains can be usefully employed to give higher yields, but this also requires development of a suitable bioprocess. Maximization of product yield during fermentation requires that a number of process parameters, some of which may interact, be optimized. Here we report the effects of different fermentative process conditions; pH, temperature and glucose concentration, on the molar hydrogen yield by a genetically optimized Escherichia coli strain, DJT135. In order to simultaneously reduce the number of the experiments, and to obtain the interactions between the variables important for achieving maximum hydrogen production, a 3(K) full factorial Box-Behnken design and response surface methodology (RSM) were employed for experimental design and analysis. A maximum molar hydrogen yield of 1.69 mol H(2)mol(-1) glucose was obtained under the optimal conditions of 75 mM glucose, 35 degrees C and pH 6.5. Thus, RSM with Box-Behnken design is a useful method for achieving higher molar hydrogen yields by metabolically engineered organisms. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  15. Modeling and simulation of graphene/palladium catalyst reformer for hydrogen generation from waste of IC engine

    Science.gov (United States)

    Rahman, A.; Aung, K. M.

    2018-01-01

    A small amount of hydrogen made by on-board reformer is added to the normal intake air and gasoline mixture in the vehicle’s engine could improves overall combustion quality by allowing nearly twice as much air for a given amount of fuel introduced into the combustion chamber. This can be justified based on the calorific value of Hydrogen (H2) 141.9 MJ/kg while the gasoline (C6.4H11.8) is 47MJ/kg. Different weight % of Pd and GO uses for the reformer model and has conducted simulation by COMSOL software. The best result found for the composition of catalyst (palladium 30% and graphene 70%). The study shows that reformer yield hydrogen 23% for the exhaust temperature of 600-900°C and 20% for 80-90°C. Pumping hydrogen may boost the fuel atomization and vaporization at engine idle condition, which could enhances the fuel combustion efficiency. Thus, this innovative technology would be able to save fuel about 12% and reduce the emission about 35%.

  16. Recent Experimental Efforts on High-Pressure Supercritical Injection for Liquid Rockets and Their Implications

    Directory of Open Access Journals (Sweden)

    Bruce Chehroudi

    2012-01-01

    Full Text Available Pressure and temperature of the liquid rocket thrust chambers into which propellants are injected have been in an ascending trajectory to gain higher specific impulse. It is quite possible then that the thermodynamic condition into which liquid propellants are injected reaches or surpasses the critical point of one or more of the injected fluids. For example, in cryogenic hydrogen/oxygen liquid rocket engines, such as Space Shuttle Main Engine (SSME or Vulcain (Ariane 5, the injected liquid oxygen finds itself in a supercritical condition. Very little detailed information was available on the behavior of liquid jets under such a harsh environment nearly two decades ago. The author had the opportunity to be intimately involved in the evolutionary understanding of injection processes at the Air Force Research Laboratory (AFRL, spanning sub- to supercritical conditions during this period. The information included here attempts to present a coherent summary of experimental achievements pertinent to liquid rockets, focusing only on the injection of nonreacting cryogenic liquids into a high-pressure environment surpassing the critical point of at least one of the propellants. Moreover, some implications of the results acquired under such an environment are offered in the context of the liquid rocket combustion instability problem.

  17. Rocket propulsion elements

    CERN Document Server

    Sutton, George P

    2011-01-01

    The definitive text on rocket propulsion-now revised to reflect advancements in the field For sixty years, Sutton's Rocket Propulsion Elements has been regarded as the single most authoritative sourcebook on rocket propulsion technology. As with the previous edition, coauthored with Oscar Biblarz, the Eighth Edition of Rocket Propulsion Elements offers a thorough introduction to basic principles of rocket propulsion for guided missiles, space flight, or satellite flight. It describes the physical mechanisms and designs for various types of rockets' and provides an unders

  18. Engineering

    National Research Council Canada - National Science Library

    Includes papers in the following fields: Aerospace Engineering, Agricultural Engineering, Chemical Engineering, Civil Engineering, Electrical Engineering, Environmental Engineering, Industrial Engineering, Materials Engineering, Mechanical...

  19. Tracer-based laser-induced fluorescence measurement technique for quantitative fuel/air-ratio measurements in a hydrogen internal combustion engine.

    Science.gov (United States)

    Blotevogel, Thomas; Hartmann, Matthias; Rottengruber, Hermann; Leipertz, Alfred

    2008-12-10

    A measurement technique for the quantitative investigation of mixture formation processes in hydrogen internal combustion engines (ICEs) has been developed using tracer-based laser-induced fluorescence (TLIF). This technique can be employed to fired and motored engine operation. The quantitative TLIF fuel/air-ratio results have been verified by means of linear Raman scattering measurements. Exemplary results of the simultaneous investigation of mixture formation and combustion obtained at an optical accessible hydrogen ICE are shown.

  20. A History of Welding on the Space Shuttle Main Engine (1975 to 2010)

    Science.gov (United States)

    Zimmerman, Frank R.; Russell, Carolyn K.

    2010-01-01

    The Space Shuttle Main Engine (SSME) is a high performance, throttleable, liquid hydrogen fueled rocket engine. High thrust and specific impulse (Isp) are achieved through a staged combustion engine cycle, combined with high combustion pressure (approx.3000psi) generated by the two-stage pump and combustion process. The SSME is continuously throttleable from 67% to 109% of design thrust level. The design criteria for this engine maximize performance and weight, resulting in a 7,800 pound rocket engine that produces over a half million pounds of thrust in vacuum with a specific impulse of 452/sec. It is the most reliable rocket engine in the world, accumulating over one million seconds of hot-fire time and achieving 100% flight success in the Space Shuttle program. A rocket engine with the unique combination of high reliability, performance, and reusability comes at the expense of manufacturing simplicity. Several innovative design features and fabrication techniques are unique to this engine. This is as true for welding as any other manufacturing process. For many of the weld joints it seemed mean cheating physics and metallurgy to meet the requirements. This paper will present a history of the welding used to produce the world s highest performance throttleable rocket engine.

  1. Replacement of chemical rocket launchers by beamed energy propulsion.

    Science.gov (United States)

    Fukunari, Masafumi; Arnault, Anthony; Yamaguchi, Toshikazu; Komurasaki, Kimiya

    2014-11-01

    Microwave Rocket is a beamed energy propulsion system that is expected to reach space at drastically lower cost. This cost reduction is estimated by replacing the first-stage engine and solid rocket boosters of the Japanese H-IIB rocket with Microwave Rocket, using a recently developed thrust model in which thrust is generated through repetitively pulsed microwave detonation with a reed-valve air-breathing system. Results show that Microwave Rocket trajectory, in terms of velocity versus altitude, can be designed similarly to the current H-IIB first stage trajectory. Moreover, the payload ratio can be increased by 450%, resulting in launch-cost reduction of 74%.

  2. Modification and testing of an engine and fuel control system for a hydrogen fuelled gas turbine

    Science.gov (United States)

    Funke, H. H.-W.; Börner, S.; Hendrick, P.; Recker, E.

    2011-10-01

    The control of pollutant emissions has become more and more important by the development of new gas turbines. The use of hydrogen produced by renewable energy sources could be an alternative. Besides the reduction of NOx emissions emerged during the combustion process, another major question is how a hydrogen fuelled gas turbine including the metering unit can be controlled and operated. This paper presents a first insight in modifications on an Auxiliary Power Unit (APU) GTCP 36300 for using gaseous hydrogen as a gas turbine fuel. For safe operation with hydrogen, the metering of hydrogen has to be fast, precise, and secure. So, the quality of the metering unit's control loop has an important influence on this topic. The paper documents the empiric determination of the proportional integral derivative (PID) control parameters for the metering unit.

  3. Dr. von Braun With German Rocket Experimenters

    Science.gov (United States)

    1930-01-01

    Dr. von Braun was among a famous group of rocket experimenters in Germany in the 1930s. This photograph is believed to be made on the occasion of Herman Oberth's Kegelduese liquid rocket engine being certified as to performance during firing. From left to right are R. Nebel, Dr. Ritter, Mr. Baermueller, Kurt Heinish, Herman Oberth, Klaus Riedel, Wernher von Braun, and an unidentified person.

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

    Science.gov (United States)

    2017-04-12

    Charts 14 March 2017 - 12 April 2017 Rocket Fuel R&D at AFRL: Recent Activities & Future Direction Matt Billingsley Air Force Research Laboratory (AFMC...Unclassified SAR 31 Matthew Billingsley N/A Q1W8 DISTRIBUTION A: Approved for Public Release; Distribution Unlimited PA Clearance Number 17163 Rocket ... Rocket Kerosene Fuels Chemical Propulsion Liquid Rocket Engines (LRE) Solid Rocket Motors (SRM) Cryogenic (Liquid O2/fuel) Storable (IRFNA, MMH

  5. 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

  6. The 2003 Goddard Rocket Replica Project: A Reconstruction of the World's First Functional Liquid Rocket System

    Science.gov (United States)

    Farr, R. A.; Elam, S. K.; Hicks, G. D.; Sanders, T. M.; London, J. R.; Mayne, A. W.; Christensen, D. L.

    2003-01-01

    As a part of NASA s 2003 Centennial of Flight celebration, engineers and technicians at Marshall Space Flight Center (MSFC), Huntsville, Alabama, in cooperation with the Alabama-Mississippi AIAA Section, have reconstructed historically accurate, functional replicas of Dr. Robert H. Goddard s 1926 first liquid- fuel rocket. The purposes of this project were to clearly understand, recreate, and document the mechanisms and workings of the 1926 rocket for exhibit and educational use, creating a vital resource for researchers studying the evolution of liquid rocketry for years to come. The MSFC team s reverse engineering activity has created detailed engineering-quality drawings and specifications describing the original rocket and how it was built, tested, and operated. Static hot-fire tests, as well as flight demonstrations, have further defined and quantified the actual performance and engineering actual performance and engineering challenges of this major segment in early aerospace history.

  7. Dynamics of short eccentric plain seals with high axial Reynolds number. [for Space Shuttle engine hydrogen fuel turbopump

    Science.gov (United States)

    Allaire, P. E.; Lee, C. C.; Gunter, E. J.

    1978-01-01

    Plain seals with high axial flow rates produce large stiffness and damping coefficients that can help stabilize high-speed rotating machinery. When the shaft is eccentric in the seal, a Bernoulli effect low-pressure region occurs on the large-clearance side of the shaft. A fluid-restoring force tends to center the shaft and reduce vibrations. This work extends the previous theory for short plain centered seals to large eccentricities using a perturbation analysis. Surface roughness effects are also included. An analysis of seals used in the Space Shuttle main engine hydrogen fuel turbopump indicates the desirability of plain seals over the labyrinth type. Experimental results confirm this.

  8. ENGINEERING DEVELOPMENT OF CERAMIC MEMBRANE REACTOR SYSTEM FOR CONVERTING NATURAL GAS TO HYDROGEN AND SYNTHESIS GAS FOR LIQUID TRANSPORTATION FUELS

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-01-01

    The objective of this contract is to research, develop and demonstrate a novel ceramic membrane reactor system for the low-cost conversion of natural gas to synthesis gas and hydrogen for liquid transportation fuels: the ITM Syngas process. Through an eight-year, three-phase program, the technology will be developed and scaled up to obtain the technical, engineering, operating and economic data necessary for the final step to full commercialization of the Gas-to-Liquids (GTL) conversion technology. This report is a summary of activities through December 1999.

  9. The high-temperature sodium coolant technology in nuclear power installations for hydrogen power engineering

    Science.gov (United States)

    Kozlov, F. A.; Sorokin, A. P.; Alekseev, V. V.; Konovalov, M. A.

    2014-05-01

    In the case of using high-temperature sodium-cooled nuclear power installations for obtaining hydrogen and for other innovative applications (gasification and fluidization of coal, deep petroleum refining, conversion of biomass into liquid fuel, in the chemical industry, metallurgy, food industry, etc.), the sources of hydrogen that enters from the reactor plant tertiary coolant circuit into its secondary coolant circuit have intensity two or three orders of magnitude higher than that of hydrogen sources at a nuclear power plant (NPP) equipped with a BN-600 reactor. Fundamentally new process solutions are proposed for such conditions. The main prerequisite for implementing them is that the hydrogen concentration in sodium coolant is a factor of 100-1000 higher than it is in modern NPPs taken in combination with removal of hydrogen from sodium by subjecting it to vacuum through membranes made of vanadium or niobium. Numerical investigations carried out using a diffusion model showed that, by varying such parameters as fuel rod cladding material, its thickness, and time of operation in developing the fuel rods for high-temperature nuclear power installations (HT NPIs) it is possible to exclude ingress of cesium into sodium through the sealed fuel rod cladding. However, if the fuel rod cladding loses its tightness, operation of the HT NPI with cesium in the sodium will be unavoidable. Under such conditions, measures must be taken for deeply purifying sodium from cesium in order to minimize the diffusion of cesium into the structural materials.

  10. Thermal Engineering Issues in Hydrogen Storage for Mobile and Portable Applications

    Science.gov (United States)

    2010-09-01

    have been studied for their hydrogen storage properties. •The physisorption of hydrogen in these materials depends primarily on the pore size ...BH.eh LNaMn(BH ) MOF 74 bridged cat./IRMOF-8 • o · PANI • · I 0 Na~r(BH..)s .PANI ~ (,) "’ fi" 8 0 ... ::r::: 6 , Q) ~ I 4 .c 0 2...weight and charging time. • Corresponding to each bed thickness, an optimum HX tube size could be determined for the lowest system weight. • Device at

  11. Evaluation and Improvement of Liquid Propellant Rocket Chugging Analysis Techniques. Part 2: a Study of Low Frequency Combustion Instability in Rocket Engine Preburners Using a Heterogeneous Stirred Tank Reactor Model. Final Report M.S. Thesis - Aug. 1987

    Science.gov (United States)

    Bartrand, Timothy A.

    1988-01-01

    During the shutdown of the space shuttle main engine, oxygen flow is shut off from the fuel preburner and helium is used to push the residual oxygen into the combustion chamber. During this process a low frequency combustion instability, or chug, occurs. This chug has resulted in damage to the engine's augmented spark igniter due to backflow of the contents of the preburner combustion chamber into the oxidizer feed system. To determine possible causes and fixes for the chug, the fuel preburner was modeled as a heterogeneous stirred tank combustion chamber, a variable mass flow rate oxidizer feed system, a constant mass flow rate fuel feed system and an exit turbine. Within the combustion chamber gases were assumed perfectly mixed. To account for liquid in the combustion chamber, a uniform droplet distribution was assumed to exist in the chamber, with mean droplet diameter determined from an empirical relation. A computer program was written to integrate the resulting differential equations. Because chamber contents were assumed perfectly mixed, the fuel preburner model erroneously predicted that combustion would not take place during shutdown. The combustion rate model was modified to assume that all liquid oxygen that vaporized instantaneously combusted with fuel. Using this combustion model, the effect of engine parameters on chamber pressure oscillations during the SSME shutdown was calculated.

  12. Engineering Hydrogen Bonding Interaction and Charge Separation in Bio-Polymers for Green Lubrication.

    Science.gov (United States)

    Mu, Liwen; Shi, Yijun; Hua, Jing; Zhuang, Wei; Zhu, Jiahua

    2017-06-08

    Synthetic additives are widely used in lubricants nowadays to upgrade lubrication properties. The potential of integrating sustainable components in modern lubricants has rarely been studied yet. In this work, two sustainable resources lignin and gelatin have been synergistically incorporated into ethylene glycol (EG), and their tribological properties were systematically investigated. The abundant hydrogen bonding sites in lignin and gelatin as well as their interchain interaction via hydrogen bonding play the dominating roles in tuning the physicochemical properties of the mixture and improving lubricating properties. Moreover, the synergistic combination of lignin and gelatin induces charge separation of gelatin that enables its preferable adsorption on the friction surface through electrostatic force and forms a robust lubrication layer. This layer will be strengthened by lignin through the interpolymer chain hydrogen bonding. At an optimized lignin:gelatin mass ratio of 1:1 and 19 wt % loading of each in EG, the friction coefficient can be greatly stabilized and the wear loss was reduced by 89% compared to pure EG. This work presents a unique synergistic phenomenon between gelatin and lignin, where hydrogen bonding and change separation are revealed as the key factor that bridges the individual components and improves overall lubricating properties.

  13. Active Edge Sites Engineering in Nickel Cobalt Selenide Solid Solutions for Highly Efficient Hydrogen Evolution

    KAUST Repository

    Xia, Chuan

    2017-01-06

    An effective multifaceted strategy is demonstrated to increase active edge site concentration in NiCoSe solid solutions prepared by in situ selenization process of nickel cobalt precursor. The simultaneous control of surface, phase, and morphology result in as-prepared ternary solid solution with extremely high electrochemically active surface area (C = 197 mF cm), suggesting significant exposure of active sites in this ternary compound. Coupled with metallic-like electrical conductivity and lower free energy for atomic hydrogen adsorption in NiCoSe, identified by temperature-dependent conductivities and density functional theory calculations, the authors have achieved unprecedented fast hydrogen evolution kinetics, approaching that of Pt. Specifically, the NiCoSe solid solutions show a low overpotential of 65 mV at -10 mV cm, with onset potential of mere 18 mV, an impressive small Tafel slope of 35 mV dec, and a large exchange current density of 184 μA cm in acidic electrolyte. Further, it is shown that the as-prepared NiCoSe solid solution not only works very well in acidic electrolyte but also delivers exceptional hydrogen evolution reaction (HER) performance in alkaline media. The outstanding HER performance makes this solid solution a promising candidate for mass hydrogen production.

  14. Reaction engineering for materials processing in space: Reduction of ilmenite by hydrogen and carbon monoxide

    Science.gov (United States)

    Zhao, Y.; Shadman, F.

    1991-01-01

    Oxygen is a consumable material which needs to be produced continuously in most space missions. Its use for propulsion as well as life support makes oxygen one of the largest volume chemicals to be produced in space. Production of oxygen from lunar materials is of particular interest and is very attractive possibility. The kinetics and mechanism of reduction of ilmenite by carbon monoxide and hydrogen at 800 to 1100 C were investigated. The temporal profiles of conversion for carbon monoxide have a sigmoidal shape and indicate the presence of three different stages (induction, acceleration, and deceleration) during the reduction reaction. The apparent activation energy decreases from 18 kcal/mole at 10 percent conversion to 10 kcal/mole at 50 percent conversion. The reaction is first order with respect to carbon monoxide under the experimental conditions studied. Both SEM and EDX analysis show that the diffusion of Fe product away from the reaction front and through the TiO2 phase, followed by the nucleation and growth of a separate Fe phase are important steps affecting the process kinetics. The results from hydrogen reduction show that the mechanism of ilmenite reduction by hydrogen is similar to that by carbon monoxide. However, the titanium dioxide can be further reduced by hydrogen at 800 to 1000 C. The detailed comparison and theoretical modeling of both reduction processes is presented.

  15. Engineering Two-Dimensional Transition Metal Dichalcogenide Catalysts for Water-Splitting Hydrogen Generation

    DEFF Research Database (Denmark)

    Cao, Xianyi; Tang, Yingying; Duus, Jens Øllgaard

    2017-01-01

    Development of advanced energy conversion and storage technologies is essential for optimizing the integration of sustainable energy resources into current-running power grid systems. As one of the key energy-storage carriers, hydrogen (H2) possesses ultrahigh gravimetric energy density, eco...

  16. A preliminary systems-engineering study of an advanced nuclear-electrolytic hydrogen-production facility

    Science.gov (United States)

    Escher, W. J. D.; Donakowski, T. D.; Tison, R. R.

    1975-01-01

    An advanced nuclear-electrolytic hydrogen-production facility concept was synthesized at a conceptual level with the objective of minimizing estimated hydrogen-production costs. The concept is a closely-integrated, fully-dedicated (only hydrogen energy is produced) system whose components and subsystems are predicted on ''1985 technology.'' The principal components are: (1) a high-temperature gas-cooled reactor (HTGR) operating a helium-Brayton/ammonia-Rankine binary cycle with a helium reactor-core exit temperature of 980 C, (2) acyclic d-c generators, (3) high-pressure, high-current-density electrolyzers based on solid-polymer electrolyte technology. Based on an assumed 3,000 MWt HTGR the facility is capable of producing 8.7 million std cu m/day of hydrogen at pipeline conditions, 6,900 kPa. Coproduct oxygen is also available at pipeline conditions at one-half this volume. It has further been shown that the incorporation of advanced technology provides an overall efficiency of about 43 percent, as compared with 25 percent for a contemporary nuclear-electric plant powering close-coupled contemporary industrial electrolyzers.

  17. Pulse Detonation Rocket MHD Power Experiment

    Science.gov (United States)

    Litchford, Ron J.; Cook, Stephen (Technical Monitor)

    2002-01-01

    A pulse detonation research engine (MSFC (Marshall Space Flight Center) Model PDRE (Pulse Detonation Rocket Engine) G-2) has been developed for the purpose of examining integrated propulsion and magnetohydrodynamic power generation applications. The engine is based on a rectangular cross-section tube coupled to a converging-diverging nozzle, which is in turn attached to a segmented Faraday channel. As part of the shakedown testing activity, the pressure wave was interrogated along the length of the engine while running on hydrogen/oxygen propellants. Rapid transition to detonation wave propagation was insured through the use of a short Schelkin spiral near the head of the engine. The measured detonation wave velocities were in excess of 2500 m/s in agreement with the theoretical C-J velocity. The engine was first tested in a straight tube configuration without a nozzle, and the time resolved thrust was measured simultaneously with the head-end pressure. Similar measurements were made with the converging-diverging nozzle attached. The time correlation of the thrust and head-end pressure data was found to be excellent. The major purpose of the converging-diverging nozzle was to configure the engine for driving an MHD generator for the direct production of electrical power. Additional tests were therefore necessary in which seed (cesium-hydroxide dissolved in methanol) was directly injected into the engine as a spray. The exhaust plume was then interrogated with a microwave interferometer in an attempt to characterize the plasma conditions, and emission spectroscopy measurements were also acquired. Data reduction efforts indicate that the plasma exhaust is very highly ionized, although there is some uncertainty at this time as to the relative abundance of negative OH ions. The emission spectroscopy data provided some indication of the species in the exhaust as well as a measurement of temperature. A 24-electrode-pair segmented Faraday channel and 0.6 Tesla permanent

  18. The flight of uncontrolled rockets

    CERN Document Server

    Gantmakher, F R; Dryden, H L

    1964-01-01

    International Series of Monographs on Aeronautics and Astronautics, Division VII, Volume 5: The Flight of Uncontrolled Rockets focuses on external ballistics of uncontrolled rockets. The book first discusses the equations of motion of rockets. The rocket as a system of changing composition; application of solidification principle to rockets; rotational motion of rockets; and equations of motion of the center of mass of rockets are described. The text looks at the calculation of trajectory of rockets and the fundamentals of rocket dispersion. The selection further focuses on the dispersion of f

  19. Mars Sample Return and Flight Test of a Small Bimodal Nuclear Rocket and ISRU Plant

    Science.gov (United States)

    George, Jeffrey A.; Wolinsky, Jason J.; Bilyeu, Michael B.; Scott, John H.

    2014-01-01

    A combined Nuclear Thermal Rocket (NTR) flight test and Mars Sample Return mission (MSR) is explored as a means of "jump-starting" NTR development. Development of a small-scale engine with relevant fuel and performance could more affordably and quickly "pathfind" the way to larger scale engines. A flight test with subsequent inflight postirradiation evaluation may also be more affordable and expedient compared to ground testing and associated facilities and approvals. Mission trades and a reference scenario based upon a single expendable launch vehicle (ELV) are discussed. A novel "single stack" spacecraft/lander/ascent vehicle concept is described configured around a "top-mounted" downward firing NTR, reusable common tank, and "bottom-mount" bus, payload and landing gear. Requirements for a hypothetical NTR engine are described that would be capable of direct thermal propulsion with either hydrogen or methane propellant, and modest electrical power generation during cruise and Mars surface insitu resource utilization (ISRU) propellant production.

  20. Collaboration with and without Coauthorship: Rocket Science Versus Economic Science

    OpenAIRE

    Barnett, William

    2015-01-01

    This essay is about my prior experiences as a rocket scientist on Apollo rocket engines, with comparison to my subsequent experiences at the Federal Reserve, and in academia, with emphasis upon differences in collaboration and scientific methodology. A primary difference is in the emphasis on measurement.

  1. Not just rocket science

    Energy Technology Data Exchange (ETDEWEB)

    MacAdam, S.; Anderson, R. [Celan Energy Systems, Rancho Cordova, CA (United States)

    2007-10-15

    The paper explains a different take on oxyfuel combustion. Clean Energy Systems (CES) has integrated aerospace technology into conventional power systems, creating a zero-emission power generation technology that has some advantages over other similar approaches. When using coal as a feedstock, the CES process burns syngas rather than raw coal. The process uses recycled water and steam to moderate the temperature, instead of recycled CO{sub 2}. With no air ingress, the CES process produces very pure CO{sub 2}. This makes it possible to capture over 99% of the CO{sub 2} resulting from combustion. CES uses the combustion products to drive the turbines, rather than indirectly raising steam for steam turbines, as in the oxyfuel process used by companies such as Vattenfall. The core of the process is a high-pressure oxy-combustor adapted from rocket engine technology. This combustor burns gaseous or liquid fuels with gaseous oxygen in the presence of water. Fuels include natural gas, coal or coke-derived synthesis gas, landfill and biodigester gases, glycerine solutions and oil/water emulsion. 2 figs.

  2. General Motors: Final Report for Hydrogen Storage Engineering Center of Excellence

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Mei [General Motors Company, Warren, MI (United States); Chakraborty, Amlan [General Motors Company, Warren, MI (United States); Hou, Peter [General Motors Company, Warren, MI (United States); Kaisare, Niklet [General Motors Company, Warren, MI (United States); Jorgensen, Scott [General Motors Company, Warren, MI (United States); Kumar, Sudarshan [General Motors Company, Warren, MI (United States); Li, Changpeng [General Motors Company, Warren, MI (United States); Ortmann, Jerome [General Motors Company, Warren, MI (United States); Raju, M. [General Motors Company, Warren, MI (United States); Vadivelu, S. Kumar [General Motors Company, Warren, MI (United States)

    2015-06-30

    As part of the HSECoE team, the GM team built system models and detailed transport models for on-board hydrogen storage systems using metal hydrides and adsorbent materials. Detailed transport models have been developed for both the metal hydride and adsorbent systems with a focus on optimization of heat exchanger designs with the objective of minimizing the heat exchanger mass. We also performed work in collaboration with our partners on storage media structuring and enhancement studies for the metal hydride and adsorbent materials. Since the hydrogen storage materials are generally characterized by low density and low thermal conductivity, we conducted experiments to form pellets and add thermal conductivity enhancers to the storage material, and to improve cycling stability and durability of the metal hydride and adsorbent materials. Refueling of a MOF-5 pellet with cryogenic hydrogen was studied by developing a detailed two-dimensional axisymmetric COMSOL® model of the process. The effects of pellet permeability, thermal conductivity, and thermal conductivity enhancers were investigated. Our key area of focus has been on designing and building a cryo-adsorption vessel for validation of cryo-adsorption models. The 3-L cryogenic tank was used to study the fast fill and discharge dynamics of a cryo-adsorbent storage system, both experimentally and numerically.

  3. Stand for Experimental Evaluation of Effects of Hydrogen Use in Internal Combustion Engines

    Directory of Open Access Journals (Sweden)

    Levente B.

    2015-04-01

    Full Text Available Hydroxy gas or the Brown gas or simply HHO, as it is called more often now days, is a highly flammable gas that has been around since the beginning of the XX-th century, when scientist Yull Brown has dedicated his work to study the properties and means of production of HHO by water electrolysis. In the second half of the century, the oil crisis, the simplicity of HHO production and its high combustion temperature and flame propagation have spurred the interest of ”garage inventors” around the world, who started doing practical experiments with HHO injection on personal vehicles and power-generators, in trying to reduce gas mileage, increase the engine performance and lower tailpipe emissions. Today, this technology is being rediscovered, again due to higher fuel prices and this time also due to some increasing concerns over global warming. Many have learned that HHO injection into the IC engine improves the gas mileage and reduces emissions, some reporting fuel savings of up to 40%, while others even claim to have reached the performance of operating their engines on HHO entirely produced onboard of the running vehicle. There are also reports that claim increased life span of the engine and engine lubrication, due to reduction effect of HHO on the solid hydrocarbon depositions onto the engine critical components, like pistons, valves, cylinder walls, etc. In this regard, the University Politehnica Timisoara Department of Mechanical Machines, Equipment and Transportation and Department for Applied Chemistry and Engineering of Inorganic Compounds and Environment, have joined together in a project to study and understand the mechanism that take place during HHO injection to IC engines, quantify the benefits and develop safer, better and more reliable materials for HHO on-demand and on-board production by water electrolysis.

  4. Review of the Modelling of Slush Hydrogen Flows

    Directory of Open Access Journals (Sweden)

    Ph. Reynier

    2011-09-01

    Full Text Available In the perspective of mass savings related to future launchers, the use of slush hydrogen as propellant is attractive. Due to its higher density, the use of slush hydrogen could lead to the mass reduction of propellant and the utilisation of smaller tanks. However, the use of slush hydrogen in rocket engines presents different challenges. The first one is the production of slush hydrogen. Other aspects are the problems induced by the use of slush in a propulsion system: slush flow in pipes and singularities, design of a compatible turbopump and injection of slush in a combustion chamber. In order to prepare numerical tools for supporting future technical activities, ISA has undertaken a large effort in the direction of the modelling of slush hydrogen flows. The work has been split in two parts: the engineering modelling for slush flows in pipe lines and the preparation of more advanced models. At first, an extensive review of the available studies on this topic reported in the literature has been undertaken. Then, an engineering model has been selected and incorporated in a numerical tool. The different issues in term of modelling related to slush hydrogen have been identified and a potential model for future computational fluid dynamics calculations has been selected.

  5. Large Liquid Rocket Testing: Strategies and Challenges

    Science.gov (United States)

    Rahman, Shamim A.; Hebert, Bartt J.

    2005-01-01

    Rocket propulsion development is enabled by rigorous ground testing in order to mitigate the propulsion systems risks that are inherent in space flight. This is true for virtually all propulsive devices of a space vehicle including liquid and solid rocket propulsion, chemical and non-chemical propulsion, boost stage and in-space propulsion and so forth. In particular, large liquid rocket propulsion development and testing over the past five decades of human and robotic space flight has involved a combination of component-level testing and engine-level testing to first demonstrate that the propulsion devices were designed to meet the specified requirements for the Earth to Orbit launchers that they powered. This was followed by a vigorous test campaign to demonstrate the designed propulsion articles over the required operational envelope, and over robust margins, such that a sufficiently reliable propulsion system is delivered prior to first flight. It is possible that hundreds of tests, and on the order of a hundred thousand test seconds, are needed to achieve a high-reliability, flight-ready, liquid rocket engine system. This paper overviews aspects of earlier and recent experience of liquid rocket propulsion testing at NASA Stennis Space Center, where full scale flight engines and flight stages, as well as a significant amount of development testing has taken place in the past decade. The liquid rocket testing experience discussed includes testing of engine components (gas generators, preburners, thrust chambers, pumps, powerheads), as well as engine systems and complete stages. The number of tests, accumulated test seconds, and years of test stand occupancy needed to meet varying test objectives, will be selectively discussed and compared for the wide variety of ground test work that has been conducted at Stennis for subscale and full scale liquid rocket devices. Since rocket propulsion is a crucial long-lead element of any space system acquisition or

  6. Engineering Development of Ceramic Membrane Reactor System for Converting Natural Gas to Hydrogen and Synthesis Gas for Liquid Transportation Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Air Products and Chemicals

    2008-09-30

    An Air Products-led team successfully developed ITM Syngas technology from the concept stage to a stage where a small-scale engineering prototype was about to be built. This technology produces syngas, a gas containing carbon monoxide and hydrogen, by reacting feed gas, primarily methane and steam, with oxygen that is supplied through an ion transport membrane. An ion transport membrane operates at high temperature and oxygen ions are transported through the dense membrane's crystal lattice when an oxygen partial pressure driving force is applied. This development effort solved many significant technical challenges and successfully scaled-up key aspects of the technology to prototype scale. Throughout the project life, the technology showed significant economic benefits over conventional technologies. While there are still on-going technical challenges to overcome, the progress made under the DOE-funded development project proved that the technology was viable and continued development post the DOE agreement would be warranted.

  7. A Study on the Combustion Characteristics of a Generator Engine Running on a Mixture of Syngas and Hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seung Hyun; Park, Cheol Woong [University of Science and Technology, Daejeon (Korea, Republic of); Lee, Sun Youp; Kim, Chang Gi [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)

    2011-07-15

    Internal combustion engines running on syngas, which can be obtained from biomass or organic wastes, are expected to be one of the suitable alternatives for power generation, because they are environment-friendly and do not contribute to the depletion of fossil fuels. However, syngas has variable compositions and a lower heating value than pure natural gas, owing to which the combustion conditions need to be adjusted in order to achieve stable combustion. In this study, a gas that has the same characteristics as syngas, such as low heating value (LHV), was produced by mixing N{sub 2} with compressed natural gas (CNG). In addition, this study investigates the combustion characteristics of syngas when it is mixed with hydrogen in a ratio ranging from 10% to 30% with a constant LHV of total gas.

  8. Gaseous Helium Reclamation at Rocket Test Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — GHe reclamation is critical in reducing operating costs at rocket engine test facilities. Increases in cost and shortages of helium will dramatically impact testing...

  9. Ultraviolet photographic pyrometer used in rocket exhaust analysis

    Science.gov (United States)

    Levin, B. P.

    1966-01-01

    Ultraviolet photographic pyrometer investigates the role of carbon as a thermal radiator and determines the geometry, location, and progress of afterburning phenomena in the exhaust plume of rocket engines using liquid oxygen/RP-1 as propellant.

  10. Analytical and experimental investigation of rubbing interaction in labyrinth seals for a liquid hydrogen fuel pump. [space shuttle main engine

    Science.gov (United States)

    Dolan, F. X.; Kennedy, F. E.; Schulson, E. M.

    1984-01-01

    Cracking of the titanium knife edges on the labyrinth seals of the liquid hydrogen fuel pump in the Space Shuttle main engine is considered. Finite element analysis of the thermal response of the knife edge in sliding contact with the wear ring surface shows that interfacial temperatures can be quite high and they are significantly influenced by the thermal conductivity of the surfaces in rubbing contact. Thermal shock experiments on a test specimen similar to the knife edge geometry demonstrate that cracking of the titanium alloy is possible in a situation involving repeated thermal cycles over a wide temperature range, as might be realized during a rub in the liquid hydrogen fuel pump. High-speed rub interaction tests were conducted using a representative knife edge and seal geometry over a broad range of interaction rates and alternate materials were experimentally evaluated. Plasma-sprayed aluminum-graphite was found to be significantly better than presently used aluminum alloy seals from the standpoint of rub performance. Ion nitriding the titanium alloy knife-edges also improved rub performance compared to the untreated baseline.

  11. Design study of RL10 derivatives. Volume 3, part 2: Operational and flight support plan. [analysis of transportation requirements for rocket engine in support of space tug program

    Science.gov (United States)

    Shubert, W. C.

    1973-01-01

    Transportation requirements are considered during the engine design layout reviews and maintenance engineering analyses. Where designs cannot be influenced to avoid transportation problems, the transportation representative is advised of the problems permitting remedies early in the program. The transportation representative will monitor and be involved in the shipment of development engine and GSE hardware between FRDC and vehicle manufacturing plant and thereby will be provided an early evaluation of the transportation plans, methods and procedures to be used in the space tug support program. Unanticipated problems discovered in the shipment of development hardware will be known early enough to permit changes in packaging designs and transportation plans before the start of production hardware and engine shipments. All conventional transport media can be used for the movement of space tug engines. However, truck transport is recommended for ready availability, variety of routes, short transit time, and low cost.

  12. Engineered Hydrogen-Bonded Glycopolymer Capsules and Their Interactions with Antigen Presenting Cells.

    Science.gov (United States)

    Kempe, Kristian; Xiang, Sue D; Wilson, Paul; Rahim, Md Arifur; Ju, Yi; Whittaker, Michael R; Haddleton, David M; Plebanski, Magdalena; Caruso, Frank; Davis, Thomas P

    2017-02-22

    Hollow glycopolymer microcapsules were fabricated by hydrogen-bonded layer-by-layer (LbL) assembly, and their interactions with a set of antigen presenting cells (APCs), including dendritic cells (DCs), macrophages (MACs), and myeloid derived suppressor cells (MDSCs), were investigated. The glycopolymers were obtained by cascade postpolymerization modifications of poly(oligo(2-ethyl-2-oxazoline methacrylate)-stat-glycidyl methacrylate) involving the modification of the glycidyl groups with propargylamine and the subsequent attachment of mannose azide by copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC). Multilayer assembly of the hydrogen-bonding pair (glycopolymer/poly(methacrylic acid) (PMA)) onto planar and particulate supports (SiO2 particles, d = 1.16 μm) yielded stable glycopolymer films upon cross-linking by CuAAC. The silica (SiO2) particle templates were removed yielding hollow monodisperse capsules, as demonstrated by fluorescence and scanning electron microscopy. Cellular uptake studies using flow cytometry revealed the preferential uptake of the capsules by DCs when compared to MACs or MDSCs. Mannosylated capsules showed a cytokine independent cis-upregulation of CD80 specifically on DCs and a trans-downregulation of PDL-1 on MDSCs. Thus, the glycopolymer capsules may have potential as vaccine carriers, as they are able to upregulate costimulatory molecules for immune cell stimulation on DCs and at the same time downregulate immune inhibitory receptors on suppressor APC such as MDSCs.

  13. Environmental Engineering of Pd Nanoparticle Catalysts for Catalytic Hydrogenation of CO2 and Bicarbonate.

    Science.gov (United States)

    Lee, Li-Chen; Xing, Xiaoyu; Zhao, Yan

    2017-10-24

    The extraordinary catalytic properties of enzymes are derived not only from their catalytic groups but also the unique properties of the active site. Tuning the microenvironment of synthetic catalysts is expected to enhance their performance if effective strategies can be developed. Interfacially cross-linked reverse micelles were prepared from three different cross-linkable surfactants. Pd nanoparticles were deposited in the core of the micelle for the catalytic hydrogenation of bicarbonate and CO2. The catalytic performance was found to depend heavily on the nature of the headgroup of the surfactant. Quaternary ammonium-based surfactants through ion exchange could bring bicarbonate to the catalytic center, whereas tertiary amine-based surfactants worked particularly well in CO2 hydrogenation, with turnover numbers an order of magnitude higher than that of commercially available Pd/C. The amines were proposed to bring CO2 to the proximity of the catalysts through reversible formation of carbamate, in the nanospace of the hydrophilic core of the cross-linked reverse micelle. In the bicarbonate reduction, additional improvement of the catalysts was achieved through localized sol-gel synthesis that introduced metal oxide near the catalytic metal.

  14. Reversible Storage of Hydrogen and Natural Gas in Nanospace-Engineered Activated Carbons

    Science.gov (United States)

    Romanos, Jimmy; Beckner, Matt; Rash, Tyler; Yu, Ping; Suppes, Galen; Pfeifer, Peter

    2012-02-01

    An overview is given of the development of advanced nanoporous carbons as storage materials for natural gas (methane) and molecular hydrogen in on-board fuel tanks for next-generation clean automobiles. High specific surface areas, porosities, and sub-nm/supra-nm pore volumes are quantitatively selected by controlling the degree of carbon consumption and metallic potassium intercalation into the carbon lattice during the activation process. Tunable bimodal pore-size distributions of sub-nm and supra-nm pores are established by subcritical nitrogen adsorption. Optimal pore structures for gravimetric and volumetric gas storage, respectively, are presented. Methane and hydrogen adsorption isotherms up to 250 bar on monolithic and powdered activated carbons are reported and validated, using several gravimetric and volumetric instruments. Current best gravimetric and volumetric storage capacities are: 256 g CH4/kg carbon and 132 g CH4/liter carbon at 293 K and 35 bar; 26, 44, and 107 g H2/kg carbon at 303, 194, and 77 K respectively and 100 bar. Adsorbed film density, specific surface area, and binding energy are analyzed separately using the Clausius-Clapeyron equation, Langmuir model, and lattice gas models.

  15. Microelectronic Spare and Repair Part Status Analysis for the Multiple Launch Rocket System (MLRS)

    National Research Council Canada - National Science Library

    Maddux, Gary

    1999-01-01

    .... IOD required management and engineering support In performing microelectronic technology and availability assessments for the impact of nonavailability on the Multiple Launch Rocket System (MLRS...

  16. Hot Hydrogen Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    W. David Swank

    2007-02-01

    The core in a nuclear thermal rocket will operate at high temperatures and in hydrogen. One of the important parameters in evaluating the performance of a nuclear thermal rocket is specific impulse, ISp. This quantity is proportional to the square root of the propellant’s absolute temperature and inversely proportional to square root of its molecular weight. Therefore, high temperature hydrogen is a favored propellant of nuclear thermal rocket designers. Previous work has shown that one of the life-limiting phenomena for thermal rocket nuclear cores is mass loss of fuel to flowing hydrogen at high temperatures. The hot hydrogen test facility located at the Idaho National Lab (INL) is designed to test suitability of different core materials in 2500°C hydrogen flowing at 1500 liters per minute. The facility is intended to test non-uranium containing materials and therefore is particularly suited for testing potential cladding and coating materials. In this first installment the facility is described. Automated Data acquisition, flow and temperature control, vessel compatibility with various core geometries and overall capabilities are discussed.

  17. THE EFFECT OF ADDING HYDROGEN ON THE PERFORMANCE AND THE CYCLIC VARIABILITY OF A SPARK IGNITION ENGINE POWERED BY NATURAL GAS

    Directory of Open Access Journals (Sweden)

    Andrej Chríbik

    2014-02-01

    Full Text Available This paper deals with the influence of blending hydrogen (from 0 to 50% vol. on the parameters and the cyclic variability of a Lombardini LGW702 combustion engine powered by natural gas. The experimental measurements were carried out at various air excess ratios and at various angles of spark advance, at an operating speed of 1500 min−1. An analysis of the combustion pressure showed that as the proportion of hydrogen in the mixture increases, the maximum pressure value also increases. However, at the same time the cyclic variability decreases. Both the ignition-delay period and the period of combustion of the mixture become shorter, which requires optimization of the spark advance angle for various proportions of hydrogen in the fuel. The increasing proportion of hydrogen extends the flammability limit to the area of lean-burn mixtures and, at the same time, the coefficient of cyclic variability of the mean indicated pressure decreases.

  18. Water bottle rocket in undergraduate laboratory

    Science.gov (United States)

    Schultz, William

    2012-11-01

    In the winter semester of 2012, we implemented the modeling and testing of a water bottle rocket in ME 495, the Senior Laboratory in Mechanical Engineering at the University of Michigan. The four week lab was the most well received by the students in recent memory. There were significant challenges, but the result was a thorough review of their undergraduate fluids class with some advanced concepts such as directional stability of a projectile. The student teams designed their own rockets based on one of many standard 20 ounce soft drink bottles. The culminating contest brought impressive results and a surprise ending.

  19. Spectral analysis and self-adjusting mechanism for oscillation phenomenon in hydrogen-oxygen continuously rotating detonation engine

    Directory of Open Access Journals (Sweden)

    Liu Yusi

    2015-06-01

    Full Text Available The continuously rotating detonation engine (CRDE is a new concept of engines for aircraft and spacecraft. Quasi-stable continuously rotating detonation (CRD can be observed in an annular combustion chamber, but the sustaining, stabilizing and adjusting mechanisms are not yet clear. To learn more deeply into the CRDE, experimental studies have been carried out to investigate hydrogen-oxygen CRDE. Pressure histories are obtained during each shot, which show that stable CRD waves are generated in the combustor, when feeding pressures are higher than 0.5 MPa for fuel and oxidizer, respectively. Each shot can keep running as long as fresh gas feeding maintains. Close-up of the pressure history shows the repeatability of pressure peaks and indicates the detonation velocity in hydrogen–oxygen CRD, which proves the success of forming a stable CRD in the annular chamber. Spectrum of the pressure history matches the close-up analysis and confirms the CRD. It also shows multi-wave phenomenon and affirms the fact that in this case a single detonation wave is rotating in the annulus. Moreover, oscillation phenomenon is found in pressure peaks and a self-adjusting mechanism is proposed to explain the phenomenon.

  20. A Systems Engineering Approach to Evolution of Physics based Prognostic Health Management of Aging Solid Rocket Motor System Assets (Conference Paper with Briefing Charts)

    Science.gov (United States)

    2017-10-09

    performance expectations. This paper outlines the general systems engineering approach, philosophy , and payoff of creating a PHM system, and illustrates when...systems engineering approach, philosophy , and payoff of creating a PHM system, and illustrates when and why mechanistic approaches are best. The...paper concludes with a discussion of the results obtained from the process on a demonstration system. 1. INTRODUCTION Today’s environment of

  1. Another Look at Rocket Thrust

    Science.gov (United States)

    Hester, Brooke; Burris, Jennifer

    2012-01-01

    Rocket propulsion is often introduced as an example of Newton's third law. The rocket exerts a force on the exhaust gas being ejected; the gas exerts an equal and opposite force--the thrust--on the rocket. Equivalently, in the absence of a net external force, the total momentum of the system, rocket plus ejected gas, remains constant. The law of…

  2. Oxide Protective Coats for Ir/Re Rocket Combustion Chambers

    Science.gov (United States)

    Fortini, Arthur; Tuffias, Robert H.

    2003-01-01

    An improved material system has been developed for rocket engine combustion chambers for burning oxygen/ hydrogen mixtures or novel monopropellants, which are highly oxidizing at operating temperatures. The baseline for developing the improved material system is a prior iridium/rhenium system for chambers burning nitrogen tetroxide/monomethyl hydrazine mixtures, which are less oxidizing. The baseline combustion chamber comprises an outer layer of rhenium that provides structural support, plus an inner layer of iridium that acts as a barrier to oxidation of the rhenium. In the improved material system, the layer of iridium is thin and is coated with a thermal fatigue-resistant refractory oxide (specifically, hafnium oxide) that serves partly as a thermal barrier to decrease the temperature and thus the rate of oxidation of the rhenium. The oxide layer also acts as a barrier against the transport of oxidizing species to the surface of the iridium. Tests in which various oxygen/hydrogen mixtures were burned in iridium/rhenium combustion chambers lined with hafnium oxide showed that the operational lifetimes of combustion chambers of the improved material system are an order of magnitude greater than those of the baseline combustion chambers.

  3. A CFD-model of the Fluid Flow in a Hydrogen Peroxide Monopropellant Rocket Engine in ANSYS Fluent 16.2

    OpenAIRE

    Vestnes, Frida

    2016-01-01

    The use of hydrazine in monopropellant thrusters has dominated the market for several decades. Due to the toxic nature of hydrazine, the interest in developing thrusters based on green propellants has increased. A common issue found during the development of these thrusters is the optimisation of the catalyst used to decompose the liquid propellant into a hot gas. The work presented in this thesis was therefore performed in order to evaluate if it is possible to simulate the fluid flow of hyd...

  4. The gravitational wave rocket

    OpenAIRE

    Bonnor, W. B.; Piper, M. S.

    1997-01-01

    Einstein's equations admit solutions corresponding to photon rockets. In these a massive particle recoils because of the anisotropic emission of photons. In this paper we ask whether rocket motion can be powered only by the emission of gravitational waves. We use the double series approximation method and show that this is possible. A loss of mass and gain in momentum arise in the second approximation because of the emission of quadrupole and octupole waves.

  5. Large Payload Nuclear Rockets

    Science.gov (United States)

    1964-06-01

    CORE TIMP . 5013R SOLIDO FRACrON ,0.7 REFL MAT: No 25O00 EFL TEMP. • 4000R Tg a 3.0 CM sot a 1.0 w• 20000 -.. 0U.. 1,iI.000. 0 •0 4~100 \\ 080I0...Boiling and Super - critical Pressure States," ARS 1710-61, presented at American Rocket Society Propellants, Combustion, and Liquid Rockets Conference

  6. US Rocket Propulsion Industrial Base Health Metrics

    Science.gov (United States)

    Doreswamy, Rajiv

    2013-01-01

    The number of active liquid rocket engine and solid rocket motor development programs has severely declined since the "space race" of the 1950s and 1960s center dot This downward trend has been exacerbated by the retirement of the Space Shuttle, transition from the Constellation Program to the Space launch System (SLS) and similar activity in DoD programs center dot In addition with consolidation in the industry, the rocket propulsion industrial base is under stress. To Improve the "health" of the RPIB, we need to understand - The current condition of the RPIB - How this compares to past history - The trend of RPIB health center dot This drives the need for a concise set of "metrics" - Analogous to the basic data a physician uses to determine the state of health of his patients - Easy to measure and collect - The trend is often more useful than the actual data point - Can be used to focus on problem areas and develop preventative measures The nation's capability to conceive, design, develop, manufacture, test, and support missions using liquid rocket engines and solid rocket motors that are critical to its national security, economic health and growth, and future scientific needs. center dot The RPIB encompasses US government, academic, and commercial (including industry primes and their supplier base) research, development, test, evaluation, and manufacturing capabilities and facilities. center dot The RPIB includes the skilled workforce, related intellectual property, engineering and support services, and supply chain operations and management. This definition touches the five main segments of the U.S. RPIB as categorized by the USG: defense, intelligence community, civil government, academia, and commercial sector. The nation's capability to conceive, design, develop, manufacture, test, and support missions using liquid rocket engines and solid rocket motors that are critical to its national security, economic health and growth, and future scientific needs

  7. Engineering and Coordination of Regulatory Networks and Intracellular Complexes to Maximize Hydrogen Production by Phototrophic Microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    James C. Liao

    2012-05-22

    This project is a collaboration with F. R. Tabita of Ohio State. Our major goal is to understand the factors and regulatory mechanisms that influence hydrogen production. The organisms to be utilized in this study, phototrophic microorganisms, in particular nonsulfur purple (NSP) bacteria, catalyze many significant processes including the assimilation of carbon dioxide into organic carbon, nitrogen fixation, sulfur oxidation, aromatic acid degradation, and hydrogen oxidation/evolution. Our part of the project was to develop a modeling technique to investigate the metabolic network in connection to hydrogen production and regulation. Organisms must balance the pathways that generate and consume reducing power in order to maintain redox homeostasis to achieve growth. Maintaining this homeostasis in the nonsulfur purple photosynthetic bacteria is a complex feat with many avenues that can lead to balance, as these organisms possess versatile metabolic capabilities including anoxygenic photosynthesis, aerobic or anaerobic respiration, and fermentation. Growth is achieved by using H{sub 2} as an electron donor and CO{sub 2} as a carbon source during photoautotrophic and chemoautotrophic growth, where CO{sub 2} is fixed via the Calvin-Benson-Bassham (CBB) cycle. Photoheterotrophic growth can also occur when alternative organic carbon compounds are utilized as both the carbon source and electron donor. Regardless of the growth mode, excess reducing equivalents generated as a result of oxidative processes, must be transferred to terminal electron acceptors, thus insuring that redox homeostasis is maintained in the cell. Possible terminal acceptors include O{sub 2}, CO{sub 2}, organic carbon, or various oxyanions. Cells possess regulatory mechanisms to balance the activity of the pathways which supply energy, such as photosynthesis, and those that consume energy, such as CO{sub 2} assimilation or N{sub 2} fixation. The major route for CO{sub 2} assimilation is the CBB

  8. Selection rule engineering of forbidden transitions of a hydrogen atom near a nanogap

    Science.gov (United States)

    Kim, Hyunyoung Y.; Kim, Daisik S.

    2018-01-01

    We perform an analytical study on the allowance of forbidden transitions for a hydrogen atom placed near line dipole sources, mimicking light emanating from a one-dimensional metallic nanogap. It is shown that the rapid variation of the electric field vector, inevitable in the near zone, completely breaks the selection rule of Δl=±1. While the forbidden transitions between spherically symmetric S states, such as 2S to 1S or 3S to 1S (Δl=0), are rather robust against selection rule breakage, Δl=±2 transitions such as between 3D and 1S or 3D and 2S states are very vulnerable to the spatial variation of the perturbing electric field. Transitions between 2S and 3D states are enhanced by many orders of magnitude, aided by the quadratic nature of both the perturbing Hamiltonian and D wavefunctions. The forbidden dipole moment, which approaches one Bohr radius times the electric charge in the vicinity of the gap, can be written in a simple closed form owing to the one-dimensional nature of our gap. With large enough effective volume together with the symmetric nature of the excited state wavefunctions, our work paves way towards atomic physics application of infinitely long nanogaps.

  9. Selection rule engineering of forbidden transitions of a hydrogen atom near a nanogap

    Directory of Open Access Journals (Sweden)

    Kim Hyunyoung Y.

    2018-01-01

    Full Text Available We perform an analytical study on the allowance of forbidden transitions for a hydrogen atom placed near line dipole sources, mimicking light emanating from a one-dimensional metallic nanogap. It is shown that the rapid variation of the electric field vector, inevitable in the near zone, completely breaks the selection rule of Δl=±1. While the forbidden transitions between spherically symmetric S states, such as 2S to 1S or 3S to 1S (Δl=0, are rather robust against selection rule breakage, Δl=±2 transitions such as between 3D and 1S or 3D and 2S states are very vulnerable to the spatial variation of the perturbing electric field. Transitions between 2S and 3D states are enhanced by many orders of magnitude, aided by the quadratic nature of both the perturbing Hamiltonian and D wavefunctions. The forbidden dipole moment, which approaches one Bohr radius times the electric charge in the vicinity of the gap, can be written in a simple closed form owing to the one-dimensional nature of our gap. With large enough effective volume together with the symmetric nature of the excited state wavefunctions, our work paves way towards atomic physics application of infinitely long nanogaps.

  10. Performance and specific emissions contours throughout the operating range of hydrogen-fueled compression ignition engine with diesel and RME pilot fuels

    Directory of Open Access Journals (Sweden)

    Shahid Imran

    2015-09-01

    Full Text Available This paper presents the performance and emissions contours of a hydrogen dual fueled compression ignition (CI engine with two pilot fuels (diesel and rapeseed methyl ester, and compares the performance and emissions iso-contours of diesel and rapeseed methyl ester (RME single fueling with diesel and RME piloted hydrogen dual fueling throughout the engines operating speed and power range. The collected data have been used to produce iso-contours of thermal efficiency, volumetric efficiency, specific oxides of nitrogen (NOX, specific hydrocarbons (HC and specific carbon dioxide (CO2 on a power-speed plane. The performance and emission maps are experimentally investigated, compared, and critically discussed. Apart from medium loads at lower and medium speeds with diesel piloted hydrogen combustion, dual fueling produced lower thermal efficiency everywhere across the map. For diesel and RME single fueling the maximum specific NOX emissions are centered at the mid speed, mid power region. Hydrogen dual fueling produced higher specific NOX with both pilot fuels as compared to their respective single fueling operations. The range, location and trends of specific NOX varied significantly when compared to single fueling cases. The volumetric efficiency is discussed in detail with the implications of manifold injection of hydrogen analyzed with the conclusions drawn.

  11. INVESTIGATION OF COMBUSTION, PERFORMANCE AND EMISSION CHARACTERISTICS OF SPARK IGNITION ENGINE FUELLED WITH BUTHANOL – GASOLINE MIXTURE AND A HYDROGEN ENRICHED AIR

    Directory of Open Access Journals (Sweden)

    Alfredas Rimkus

    2016-09-01

    Full Text Available In this study, spark ignition engine fuelled with buthanol-gasoline mixture and a hydrogen-enriched air was investigated. Engine performance, emissions and combustion characteristics were investigated with different buthanol (10% and 20% by volume gasoline mixtures and additionally supplied oxygen and hydrogen (HHO gas mixture (3.6 l/min in the sucked air. Hydrogen, which is in the HHO gas, improves gasoline and gasoline-buthanol mixture combustion, increases indicated pressure during combustion phase and decreases effective specific fuel consumption. Buthanol addition decreases the rate of heat release, the combustion temperature and pressure are lower which have an influence on lower nitrous oxide (NOx emission in exhaust gases. Buthanol lowers hydrocarbon (HC formation, but it increases carbon monoxide (CO concentration and fuel consumption. Combustion process analysis was carried out using AVL BOOST software. Experimental research and combustion process numerical simulation showed that using balanced buthanol and hydrogen addition, optimal efficient and ecological parameters could be achieved when engine is working with optimal spark timing, as it would work on gasoline fuel.

  12. Thermo-acoustic instabilities of high-frequency combustion in rocket engines; Instabilites thermo-acoustiques de combustion haute-frequence dans les moteurs fusees

    Energy Technology Data Exchange (ETDEWEB)

    Cheuret, F.

    2005-10-15

    Rocket motors are confined environments where combustion occurs in extreme conditions. Combustion instabilities can occur at high frequencies; they are tied to the acoustic modes of the combustion chamber. A common research chamber, CRC, allows us to study the response of a turbulent two-phase flame to acoustic oscillations of low or high amplitudes. The chamber is characterised under cold conditions to obtain, in particular, the relative damping coefficient of acoustic oscillations. The structure and frequency of the modes are determined in the case where the chamber is coupled to a lateral cavity. We have used a powder gun to study the response to a forced acoustic excitation at high amplitude. The results guide us towards shorter flames. The injectors were then modified to study the combustion noise level as a function of injection conditions. The speed of the gas determines whether the flames are attached or lifted. The noise level of lifted flames is higher. That of attached flames is proportional to the Weber number. The shorter flames whose length is less than the radius of the CRC, necessary condition to obtain an effective coupling, are the most sensitive to acoustic perturbations. The use of a toothed wheel at different positions in the chamber allowed us to obtain informations on the origin of the thermo-acoustic coupling, main objective of this thesis. The flame is sensitive to pressure acoustic oscillations, with a quasi-zero response time. These observations suggest that under the conditions of the CRC, we observe essentially the response of chemical kinetics to pressure oscillations. (author)

  13. Cycle-by-cycle Variations in a Direct Injection Hydrogen Enriched Compressed Natural Gas Engine Employing EGR at Relative Air-Fuel Ratios.

    Directory of Open Access Journals (Sweden)

    Olalekan Wasiu Saheed

    2014-07-01

    Full Text Available Since the pressure development in a combustion chamber is uniquely related to the combustion process, substantial variations in the combustion process on a cycle-by-cycle basis are occurring. To this end, an experimental study of cycle-by-cycle variation in a direct injection spark ignition engine fueled with natural gas-hydrogen blends combined with exhaust gas recirculation at relative air-fuel ratios was conducted. The impacts of relative air-fuel ratios (i.e. λ = 1.0, 1.2, 1.3 and 1.4 which represent stoichiometric, moderately lean, lean and very lean mixtures respectively, hydrogen fractions and EGR rates were studied. The results showed that increasing the relative air-fuel ratio increases the COVIMEP. The behavior is more pronounced at the larger relative air-fuel ratios. More so, for a specified EGR rate; increasing the hydrogen fractions decreases the maximum COVIMEP value just as increasing in EGR rates increases the maximum COVIMEP value. (i.e. When percentage EGR rates is increased from 0% to 17% and 20% respectively. The maximum COVIMEP value increases from 6.25% to 6.56% and 8.30% respectively. Since the introduction of hydrogen gas reduces the cycle-by-cycle combustion variation in engine cylinder; thus it can be concluded that addition of hydrogen into direct injection compressed natural gas engine employing EGR at various relative air-fuel ratios is a viable approach to obtain an improved combustion quality which correspond to lower coefficient of variation in imep, (COVIMEP in a direct injection compressed natural gas engine employing EGR at relative air-fuel ratios.

  14. Towards versatile and sustainable hydrogen production via electrocatalytic water splitting: Electrolyte engineering

    KAUST Repository

    Shinagawa, Tatsuya

    2016-12-17

    Recent advances in power generation from renewable resources necessitate conversion of electricity to chemicals and fuels in an efficient manner. The electrocatalytic water splitting is one of the most powerful and widespread technologies. The development of highly efficient, inexpensive, flexible and versatile water electrolysis devices is desired. This review discusses the significance and impact of the electrolyte on electrocatalytic performance. Depending on the circumstances where water splitting reaction is conducted, required solution conditions such as the identity and molarity of ions may significantly differ. Quantitative understanding of such electrolyte properties on electrolysis performance is effective to facilitate developing efficient electrocatalytic systems. The electrolyte can directly participate in reaction schemes (kinetics), electrode stability, and/or indirectly impacts the performance by influencing concentration overpotential (mass transport). This review aims to guide fine-tuning of the electrolyte properties, or electrolyte engineering, for (photo)electrochemical water splitting reactions.

  15. ROCKET PORT CLOSURE

    Science.gov (United States)

    Mattingly, J.T.

    1963-02-12

    This invention provides a simple pressure-actuated closure whereby windowless observation ports are opened to the atmosphere at preselected altitudes. The closure comprises a disk which seals a windowless observation port in rocket hull. An evacuated instrument compartment is affixed to the rocket hull adjacent the inner surface of the disk, while the outer disk surface is exposed to the atmosphere through which the rocket is traveling. The pressure differential between the evacuated instrument compartment and the relatively high pressure external atmosphere forces the disk against the edge of the observation port, thereby effecting a tight seai. The instrument compartment is evacuated to a pressure equal to the atmospheric pressure existing at the altitude at which it is desiretl that the closure should open. When the rocket reaches this preselected altitude, the inwardly directed atmospheric force on the disk is just equaled by the residual air pressure force within the instrument compartment. Consequently, the closure disk falls away and uncovers the open observation port. The separation of the disk from the rocket hull actuates a switch which energizes the mechanism of a detecting instrument disposed within the instrument compartment. (AE C)

  16. Towards Versatile and Sustainable Hydrogen Production through Electrocatalytic Water Splitting: Electrolyte Engineering.

    Science.gov (United States)

    Shinagawa, Tatsuya; Takanabe, Kazuhiro

    2017-04-10

    Recent advances in power generation from renewable resources necessitate conversion of electricity to chemicals and fuels in an efficient manner. Electrocatalytic water splitting is one of the most powerful and widespread technologies. The development of highly efficient, inexpensive, flexible, and versatile water electrolysis devices is desired. This review discusses the significance and impact of the electrolyte on electrocatalytic performance. Depending on the circumstances under which the water splitting reaction is conducted, the required solution conditions, such as the identity and molarity of ions, may significantly differ. Quantitative understanding of such electrolyte properties on electrolysis performance is effective to facilitate the development of efficient electrocatalytic systems. The electrolyte can directly participate in reaction schemes (kinetics), affect electrode stability, and/or indirectly impact the performance by influencing the concentration overpotential (mass transport). This review aims to guide fine-tuning of the electrolyte properties, or electrolyte engineering, for (photo)electrochemical water splitting reactions. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  17. Rocket Flight Path

    Directory of Open Access Journals (Sweden)

    Jamie Waters

    2014-09-01

    Full Text Available This project uses Newton’s Second Law of Motion, Euler’s method, basic physics, and basic calculus to model the flight path of a rocket. From this, one can find the height and velocity at any point from launch to the maximum altitude, or apogee. This can then be compared to the actual values to see if the method of estimation is a plausible. The rocket used for this project is modeled after Bullistic-1 which was launched by the Society of Aeronautics and Rocketry at the University of South Florida.

  18. Technological study and characterization of injectors with micro-orifices for bi-liquid rockets engines; Etude technologique et caracterisation d'injecteurs a micro-orifices pour propulseurs biliquides

    Energy Technology Data Exchange (ETDEWEB)

    Prevot, P. [Office National d' Etudes et de Recherches Aerospatiales (ONERA-DMAE/LP), 31 - Mauzac (France); Lecourt, R.; Foucaud, R.; D' Herbigny, F.X. [Office National d' Etudes et de Recherches Aerospatiales (ONERA-DMAE/MH), Centre du Fauga-Mauzac, 31 - Mauzac (France); Hervat, P. [Office National d' Etudes et de Recherches Aerospatiales (ONERA-DMTE/BET), Centre de Chatillon, 92 - Chatillon (France)

    2001-10-01

    Injectors for space rockets engines have been realised an tested at ONERA. Thanks to an original manufacturing technique, they allow one to get pulverization characteristics superior than those obtained with classic injectors. This improvement increases performances, allows a reduction of the size and mass of combustion chambers, while reducing manufacturing costs in the case of small series. These injectors are constituted by very thin plates fabricated by standard or chemical means. Individual plates are then assembled together by diffusion bond or brazing. This mode of fabrication allows one to conceive hydraulic circuits which would be impossible to realize with conventional metal machining. This technique, developed since the 70's in the United States by the AEROJET Company for the fabrication of platelets, complete combustion chambers and heat exchangers, has been adopted at ONERA for developing injectors at the request of CNES. An injector of this type, used at ONERA as a test tool on a very hot air generator, has given complete satisfaction. The industrial development of this technique will necessitate to achieve a technological step at the design level and to improve French capabilities in the diffusion bond process for materials others that titanium, such as stainless steel. (authors)

  19. Semi-rational engineering of cellobiose dehydrogenase for improved hydrogen peroxide production.

    Science.gov (United States)

    Sygmund, Christoph; Santner, Paul; Krondorfer, Iris; Peterbauer, Clemens K; Alcalde, Miguel; Nyanhongo, Gibson S; Guebitz, Georg M; Ludwig, Roland

    2013-04-23

    all found to carry the same amino acid exchange in the cdh gene (N700S). The sensitive location of the five targeted amino acid positions in the active site of CDH explains the high rate of variants with decreased or entirely abolished activity. The discovery of only one beneficial exchange indicates that a dehydrogenase's oxygen turnover is a complex phenomenon and the increase therefore not an easy target for protein engineering.

  20. Testing and analysis of the impact on engine cycle parameters and control system modifications using hydrogen or methane as fuel in an industrial gas turbine

    Science.gov (United States)

    Funke, H. H.-W.; Keinz, J.; Börner, S.; Hendrick, P.; Elsing, R.

    2016-07-01

    The paper highlights the modification of the engine control software of the hydrogen (H2) converted gas turbine Auxiliary Power Unit (APU) GTCP 36-300 allowing safe and accurate methane (CH4) operation achieved without mechanical changes of the metering unit. The acceleration and deceleration characteristics of the engine controller from idle to maximum load are analyzed comparing H2 and CH4. Also, the paper presents the influence on the thermodynamic cycle of gas turbine resulting from the different fuels supported by a gas turbine cycle simulation of H2 and CH4 using the software GasTurb.