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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Study of chugging instability with liquid- oxygen and gaseous-hydrogen combustors
Test firings and analytical model used to evaluate chugging instability in subscale experiments with LOX-gaseous hydrogen combustors
Experimental verification of a double dead time model describing chugging in liquid bipropellant rocket engines
Double dead-time model for combustion stability analysis in liquid bipropellant rocket engines
The flammability of electronic components in spacecraft environments Final report, 15 Mar. - 15 Oct. 1968
Mathematical model for combustion at zero gravity in spacecraft environments
Technique for assessing potential fire hazards
Combustion hazard modeling technique limits the fire evaluation to a description of only thermal energy exchanges which are involved in the burning process, and the calculation of temperatures, temperature changes, and weight losses as a result of these energy changes.
Analysis of liquid rocket propellant engine exhaust plumes
Liquid rocket propellant engine exhaust plume flow field, discussing mathematical models for combustion chamber, throat region and nozzle
Analysis of liquid rocket engine exhaust plumes
Liquid rocket propellant engine exhaust plume flow field, discussing mathematical models for combustion chamber, throat region and nozzle
Polynomial coefficients of thermochemical data for the C-H-O-N system
Thermodynamic data are required input for the finite kinetics and equilibrium computer programs needed for modeling the combustion of hydrocarbons in the fields of energy and pollution research. Least squares determined coefficients of the curve-fitted thermodynamic data for 193 species in the C-H-O-N system are presented in card image form and are of suitable format for use by common computer programs.
Combustion instability with partial length acoustic liners
The development is discussed of analytical techniques and numerical methods for the prediction of the stability behavior of liquid propellant rocket combustors with partial length acoustic liners, injector face baffles, and nonlinear combustion responses. Three primary objectives included: (1) extension of the Green's Function integral-iteration technique previously developed so that nonlinear three dimensional wave propagation effects could be included in stability predictions; (2) development of an analytical technique and a computer program for the prediction of the damping effects caused by injector face baffles; and (3) inclusion of a nonlinear, wave distortation dependent, combustion response model in the global stability analysis and determination of its effect on combustor stability.
Solid Rocket Motor Technology
These Conference Proceedings contain the 36 papers presented at the AGARD Propulsion and Energetics Panel 53rd Symposium on "Solid Rocket Motor Technology", which was held in Oslo, Norway, 2-5 April 1979. The questions and answers after the various presentations are included as well as the Round Table Discussion. The Symposium was organized into seven sessions: Survey Papers (2); Ignition, Extinction and Internal Ballistics (8); Burn Rate Modelling and Combustion of Metal (5); New Propellants (5); Combustion Instability (7); Heat Transfer and Materials (3); and Testing and Instrumentation (6).The Symposium provided a forum for discussion and exchange between research scientists ,propellant formulators and motor technologists. Though main emphasis was placed on transient processes like ignition and extinction and on combustion instability with the various related aspects there were a number of papers dealing with propellants, their characteristics and their development. Whether the symposium achieved its initial aim, i.e. furnishing a comprehensive survey of the technology available for solid propellant rocket motors and its further development capabilities, will be assessed in a Technical Evaluation Report, to be published as AGARD Advisory Report AR 151.
An idealized model of homogeneous solid propellant combustion
The idealization of solid propellant combustion which consists of a single condensed-phase reaction and a single gas-phase reaction is discussed. A limiting-case solution to the gas-phase conservation equations is developed and tested by comparison with transformed thermocouple data. Closed-form expressions are derived for the burning rate and temperature sensitivity. Both quantities are linked explicitly to the solid and gas activation energies. It is concluded that the combustion phenomenology associated with the above idealization is still not fully understood. It is suggested that a careful study of the various limiting-case solutions tempered by a small set of numerical benchmark calculations might further such understanding.
An overview of NASA intermittent combustion engine research
This paper overviews the current program, whose objective is to establish the generic technology base for advanced aircraft I.C. engines of the early 1990's and beyond. The major emphasis of this paper is on development of the past two years. Past studies and ongoing confirmatory experimental efforts are reviewed, which show unexpectly high potential when modern aerospace technologies are applied to inherently compact and balanced I.C. engine configurations. Currently, the program is focussed on two engine concepts the stratified-charge, multi-fuel rotary, and the lightweight two-stroke diesel. A review is given of contracted and planned high performance one-rotor and one-cylinder test engine work addressing several levels of technology. Also reviewed are basic supporting efforts, e.g., the development and experimental validation of computerized airflow and combustion process models, being performed in-house at Lewis Research Center and by university grants.
An overview of NASA intermittent combustion engine research
This paper overviews the current program, whose objective is to establish the generic technology base for advanced aircraft I.C. engines of the early 1990's and beyond. The major emphasis of this paper is on development of the past two years. Past studies and ongoing confirmatory experimental efforts are reviewed, which show unexpectedly high potential when modern aerospace technologies are applied to inherently compact and balanced I.C. engine configurations. Currently, the program is focussed on two engine concepts, the stratified-charge, multi-fuel rotary and the lightweight two-stroke diesel. A review is given of contracted and planned high performance one-rotor and one-cylinder test engine work addressing several levels of technology. Also reviewed are basic supporting efforts, e.g., the development and experimental validation of computerized airflow and combustion process models, being performed in-house at Lewis Research Center and by university grants. Previously announced in STAR as N84-24583
Investigation and modeling of space shuttle main engine shutdown transient chugging
The space shuttle main engines experience a low frequency pressure pulsation in both the fuel and oxidizer preburners during the shutdown transient. This pressure pulsation, called chugging, has been linked to undesirable bearing loads and possible damage to the spark ignitor supply piping for the fuel preburner. The problem is briefly described and a model is proposed that includes: (1) a transient stirred tank reactor model for the combustion chamber, (2) a resistance capacitance model for the supply piping and (3) purge gas/liquid oxygen interface tracking.
Comprehensive modeling of a liquid rocket combustion chamber
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Solid-state combustion synthesis of ceramics and alloys in reduced gravity
Possible microgravity effects are explored in the combustion synthesis of ceramics and alloys from their constituent elements. Molten intermediates are typically present during the combustion process, thereby offering the chance for natural convection to take place. Numerical simulations suggest that the combustion front in concert with gravity may act as a partial zone-refinement mechanism which is attempting to sweep out porosity in the sample. Contrary to suggestions by dimensional analysis, no effects on the combustion rate are seen. An analytical model of the combustion velocity as a function of the gravitational field and the spreading rate of molten material gives the correct order of magnitude of the gravity effect as measured by centrifuge experiments.
Carbon deposition model for oxygen-hydrocarbon combustion, volume 1
Presented are details of the design, fabrication, and testing of subscale hardware used in the evaluation of carbon deposition characteristics of liquid oxygen and three hydrocarbon fuels for both main chamber and preburner/gas generator operating conditions. In main chamber conditions, the deposition of carbon on the combustion chamber wall was investigated at mixture ratios of 2.0 to 4.0 and at pressures of 1000 to 1500 psia. No carbon deposition on the chamber walls was detected at these main chamber mixture ratios. In preburner/gas generator operating conditions, the deposition of carbon on the turbine simulator tubes was evaluated at mixture ratios of 0.20 to 0.60 and at chamber pressures of 720 to 1650 psia. The results of the tests showed carbon deposition rate to be a strong function of mixture ratio and a weak function of chamber pressure. Further analyses evaluated the operational consequences of carbon deposition on preburner/gas generator performance. The report is in two volumes, of which this is Volume 1 covering the main body of the report plus Appendixes A through D.
Carbon Deposition Model for Oxygen-Hydrocarbon Combustion, Volume 2
Presented are details of the design, fabrication, and testing of subscale hardware used in the evaluation of carbon deposition characteristics of liquid oxygen and three hydrocarbon fuels for both main chamber and preburner/gas generator operating conditions. In main chamber conditions, the deposition of carbon on the combustion chamber wall was investigated at mixture ratios of 2.0 to 4.0 and at chamber pressures of 1000 to 1500 psia. No carbon deposition on chamber walls was detected at these main chamber mixture ratios. In preburner/gas generator operating conditions, the deposition of carbon on the turbine simulator tubes was evaluated at mixture ratios of 0.20 to 0.60 and at chamber pressures of 720 to 1650 psia. The results of the tests showed carbon deposition rate to be a strong function of mixture ratio and a weak function of chamber pressure. Further analyses evaluated the operational concequences of carbon deposition on preburner/gas generator performance. This is Volume 2 of the report, which contains data plots of all the test programs.