SEARCH · Search NASA
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.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Plasma accelerator compressible turbulent boundary layers numerical calculation taking into account MHD effects, electron thermal nonequilibrium and finite rate ionization
Nonequilibrium flow adjacent to cooling tube wall confining cascade arc plasma electrical discharge
Nonequilibrium radiation from stagnation region of high velocity spherical gas cap traveling through air
Nonequilibrium gasdynamic and thermodynamic properties of chemically reacting gas mixtures in high expansion subsonic and supersonic nozzles for selected rocket propellants
Effects of nonequilibrium free-radical content and composition variation of supersonic streams entering air breathing engines on ignition points and delays
Nonequilibrium plasma boundary layer over cathode in presence of magnetic field
Properties of nonequilibrium radiation emitted by Mars atmosphere gas mixtures
Electron temperatures measured by electrostatic probes and radar backscatter in isotropic, nonequilibrium plasma for studying planetary atmospheres
Hypersonic flow with nonequilibrium oxygen dissociation around blunt and conical bodies, considering temperature, pressure, density and compressibility factor behind normal shock
Near equilibrium shock layers nonequilibrium radiant emission calculation, noting application to Mars entry conditions
Nonequilibrium excitation in recombining nitrogen plasma nozzle flows
Thermal conditions in asymptotic region of atmospheric pressure Ar arc plasma, considering nonequilibrium ionization due to ambipolar diffusion
Ar arc plasma thermochemical nonequilibrium, using finite difference techniques for nonlinear integrodifferential equations
Multicomponent nonequilibrium air flow past axisymmetric blunt body, calculating flow distribution at various attack angles with time dependent technique
Nonequilibrium dissociating gas flow past blunt body using time dependent shock layer analysis
Resistojet power and specific impulse performance, investigating biowaste derived propellant chemical nonequilibrium effects
Nonequilibrium processes, discussing chemical reactions between electronically, vibrationally, rotationally and translationally excited reagents
Experimental measurements and theoretical calculations of the vibrational population distribution in nonequilibrium nozzle expansion flows of gas mixtures are reported. These studies were directed toward determining whether vibrational energy exchange pumping could lead to laser action on the vibrational bands of a diatomic molecule. Three different types of experiments were conducted. These showed (1) that vibrational energy was preferentially transferred from N2 to CO in supersonic nozzle flows containing these gases; (2) that under some conditions this vibrational energy exchange pumping mechanism created population inversions in the vibrational levels of CO; and (3) that at large expansion ratios the magnitude of these population inversions was sufficient to sustain lasing in the nozzle. A theoretical model was developed to calculate vibrational state population distributions in gas dynamic expansions of a mixture of diatomic gases. Although only isothermal calculations have been completed, these data indicate that population inversions are predicted for conditions similar to those obtained in the nozzle expansion flows.