http://www.ntis.gov/rss/RSSNTISCategoryList.aspxNational Technical Reports Libraryen(c) 2008, National Technical Information Service. All rights reserved.5http://www.ntis.gov/images/logoRSS.jpghttp://www.ntis.govThis experimental study focuses on two important problems relevant to acoustic coupling with condensed phase transport processes, with special relevance to liquid rocket engine and airbreathing engine combustion instabilities. The first part of this ...http://www.ntis.gov/search/product.aspx?ABBR=ADA506233In 1992, the U.S. Department of Energy forged partnerships with industry and academia under the Advanced Turbine Systems (ATS) Program to go beyond evolutionary performance gains in utility-scale gas turbine development. Agreed upon goals of 60 perce ...http://www.ntis.gov/search/product.aspx?ABBR=PB2010102157Numerical study of a 5,900 lb solid propellant thruster plume at an altitude of 118 km is performed using a combined multi-step continuum/kinetic approach. The Navier-Stokes equations are solved for the flow inside the nozzle and the first several me ...http://www.ntis.gov/search/product.aspx?ABBR=ADA506180Cross-correlation and coherence functions are used to look for periodic acoustic components in turbofan engine combustor time histories, to investigate direct and indirect combustion noise source separation based on signal propagation time delays, an ...http://www.ntis.gov/search/product.aspx?ABBR=N20090026572The aerodynamic contours for two new nozzles have been designed for the NASA Langley Research Center 8-Foot High Temperature Tunnel. The new Mach-4 and Mach-6 contours have 54.5-inch exit-diameters allowing for testing at high dynamic pressures. The ...http://www.ntis.gov/search/product.aspx?ABBR=N20090029977In order to better understand the operating characteristics of a capillary discharge based electrothermal pulsed plasma source, a variety of ignition techniques were investigated to determine performance effects and viability in a real system. Discha ...http://www.ntis.gov/search/product.aspx?ABBR=ADA506203A 2D framework for solving the sheath equations near a dielectric corner has been developed and applied in a 'quasi' 2D fashion to solve for sheath thickness and potential profile. When appropriate, boundary conditions were taken from an HPHall model ...http://www.ntis.gov/search/product.aspx?ABBR=ADA506237The desire for higher engine efficiency has resulted in the evolution of aircraft gas turbine engines from turbojets, to low bypass ratio, first generation turbofans, to today's high bypass ratio turbofans. Although increased bypass ratio has clear b ...http://www.ntis.gov/search/product.aspx?ABBR=N20090030897A Faraday probe with three concentric rings was designed and fabricated to assess the effect of gap width and probe geometry in a systematic study of the Hall thruster plume. The nested Faraday probe consisted of two concentric collector rings and an ...http://www.ntis.gov/search/product.aspx?ABBR=ADA506235This report is intended to deal fully with the German liquid fueled non-guided flak rocket-Taifun, by collecting together all the data brought back by various investigators from Germany, and combining this with an examination of parts of actual round ...http://www.ntis.gov/search/product.aspx?ABBR=ADA800683This paper presents the challenges in the ground testing of Hall effect thrusters for plasma spacecraft propulsion applications. Hall effect thrusters by virtue of their high specific impulse can reduce spacecraft station-keeping propulsion mass by a ...http://www.ntis.gov/search/product.aspx?ABBR=ADA506238The engine system concept disclosed in this proposal meets or exceeds each of the goals stated in Solicitation DARPA 08-010. Our hydraulic hybrid concept will provide extremely high efficiency while reducing weight and increasing power density. The c ...http://www.ntis.gov/search/product.aspx?ABBR=ADA505367A study of low discharge voltage Hall thruster operation revealed the existence of two operating regimes. Small variations in cathode flow fraction and magnetic field resulted in sharp changes in discharge current with constant thrust, corresponding ...http://www.ntis.gov/search/product.aspx?ABBR=ADA506241Reactive materials (RM) are a wide class of energetic materials with unique characteristics that can enable highly lethal munitions along with other applications. Most of the existing information on the behavior of these materials is phenomenological ...http://www.ntis.gov/search/product.aspx?ABBR=ADA505720This volume, the first of three volumes, is a collection of 15 unclassified/ unlimited-distribution papers which were presented at the 49th Joint Army-Navy-NASA-Air Force (JANNAF) Propulsion Meeting, held 14-16 December 1999 at the Sheraton El Conqui ...http://www.ntis.gov/search/product.aspx?ABBR=ADA375907Measurements of the heat transfer enhancement effects of concave spherical dimples have been performed under hydrogenoxygen hot-fire conditions in a subscale combustion chamber. Seven configurations were tested with a range of area densities from 15- ...http://www.ntis.gov/search/product.aspx?ABBR=ADA506200An investigation of the mixing enhancement behavior of N2 shear coaxial jets between two injector geometries is presented. A total of 20 cases with one injector geometry and 15 with the other, corresponding to different momentum flux ratios (J's) at ...http://www.ntis.gov/search/product.aspx?ABBR=ADA506218A fundamental problem in the development and validation of PHM technologies is the general shortage of realistic fault signature data. While healthy signatures can be obtained from operational systems, faults are relatively rare and difficult to obse ...http://www.ntis.gov/search/product.aspx?ABBR=ADA505652This slide presentation reviews the Knowledge Management (KM) project of the Propulsion Systems Department at Marshall Space Flight Center. KM is needed to support knowledge capture, preservation and to support an information sharing culture. The pre ...http://www.ntis.gov/search/product.aspx?ABBR=N20090028794In the laboratory we used an idealized rotorwash flow - an axisymmetric jet impinges normally on a packed bed of cohesionless particles - and measured the spatially varying flow field and entrainment flux under an axisymmetric jet over a range of jet ...http://www.ntis.gov/search/product.aspx?ABBR=ADA505857Axial waves predicted by a two-dimensional hybrid numerical model have been used to estimate electron cross field transport due to tilted waves with azimuthal components. Since the radial-axial hybrid simulation cannot model these tilted waves direct ...http://www.ntis.gov/search/product.aspx?ABBR=ADA506232We apply our experimental and modeling results of a number of burner- stabilized flames relevant to the combustion of solid propellants to calculate the burning rates of tri-amino-guanidinium- azotetrazolate (TAGzT) with and without a nitrate ester-b ...http://www.ntis.gov/search/product.aspx?ABBR=ADA505800Reducing emissions from diesel engines is one of the most important public health challenges facing the country. Despite EPA's stringent diesel engine and fuel standards taking effect over the next decade, the 20 million engines already in use will c ...http://www.ntis.gov/search/product.aspx?ABBR=PB2010101114Several unintentional hypergolic fluid related spills, fires, and explosions from the Apollo Program, the Space Shuttle Program, the Titan Program, and a few others have occurred over the past several decades. Spill sites include the following govern ...http://www.ntis.gov/search/product.aspx?ABBR=N20090029348Feasibility of using beamed microwave energy to increase thrust of solid rocket motors during launch is analyzed. Coupling of microwave radiation with internal energies of micron-sized alumina particles and the successive transfer of internal energy ...http://www.ntis.gov/search/product.aspx?ABBR=ADA506210The US Department of Energy (DOE) initiated a cooperative agreement in 1992 with the South Carolina Institute for Energy Studies (SCIES) for the Advanced Gas Turbine Systems Research (AGTSR) program. In 2002, the DOE established a follow-up cooperati ...http://www.ntis.gov/search/product.aspx?ABBR=PB2010102156