Abstract: An apparatus and method to enhance the performance of rockets engines which utilize liquid methane/oxygen propellants by injecting optimized amounts of pressurized hot helium gas into the combustion chamber with the propellants. In one embodiment, the pressurized helium gas is stored at low temperatures near those of the cryogenic propellants and is used for regenerative cooling of the combustion chamber and nozzle during rocket operation in order to raise the temperature of the helium gas before being injected into the combustion chamber.

Abstract: An apparatus and method to enhance the performance of rockets engines which utilize liquid methane/oxygen propellants by injecting optimized amounts of pressurized hot helium gas into the combustion chamber with the propellants. In one embodiment, the pressurized helium gas is stored at low temperatures near those of the cryogenic propellants and is used for regenerative cooling of the combustion chamber and nozzle during rocket operation in order to raise the temperature of the helium gas before being injected into the combustion chamber.

Abstract: A field-ionization based electrical ion thruster utilizes a single propellant that can be used in either a high specific-impulse mode, i.e., ion-thruster mode, or a low-specific-impulse mode, i.e., a cold-gas thruster mode. In one embodiment, the high specific impulse mode (ion thruster mode) utilizes a miniaturized positive-ion field-ionization chamber including a permeable substrate infused with properly oriented carbon nanotubes (CNTs), which is fed propellant from a porous injection plug made from permeable carbon or equivalent material. In one embodiment, field-electron emission from a neutralizer, such as a carbon nanotube array neutralizer, positioned after one or more accelerator grids is used for ion neutralization. In one embodiment, the low specific-impulse (cold-gas mode) uses a conventional supersonic nozzle-expansion to generate thrust.

Abstract: A negative glow discharge lamp having improved efficacy enabled by reducing the anode work function by the introduction of a metal-based gas into the lamp envelope for absorption on the anode. The metal-based gas is preferably cesium but may also, for example, be sodium.

Abstract: A negative glow discharge lamp having improved efficacy enabled by reducing the anode work function by the introduction of a metal-based gas into the lamp envelope for absorption on the anode. The metal-based gas is preferably cesium but may also, for example, be sodium.

Abstract: The present invention is directed to a method for determining, by a condensation method, the vapor pressure of a material with a known vapor pressure versus temperature characteristic, in a flow system particularly in a mercury isotope enrichment process.

Abstract: An arc discharge lamp which can be operated in any orientation without significant variation in performance includes an even number of electrodes at least equal to four, a discharge vessel including a spherical central portion and electrode mounting portions. The electrodes are mounted in the electrode mounting portions and have a substantially uniform three-dimensional distribution with respect to the central portion. The discharge lamp can be used in a lamp assembly including a switch apparatus for coupling electrical energy to a pair of the electrodes that is closest to a horizontal plane. An automatic switch apparatus includes orientation-sensitive switches, one having the same direction as each of the electrodes. The switches are interconnected such that electrical energy is coupled to a pair of electrodes in response to the orientation of the switch apparatus relative to a gravity field. The switch apparatus can be mounted in the base or within the lamp envelope of the lamp assembly.

Abstract: A high pressure sodium arc tube assembly includes a light-transmitting arc tube containing a fill material including sodium and mercury, a pair of electrodes sealed in opposite ends of the arc tube, and a filament or other resisitive member located within the arc tube and extending between opposite ends thereof. The filament is electrically connected to the electrodes. The filament provides a sufficient electric field and an abundance of electrons dispersed throughout the discharge region to initiate an arc discharge when the electrodes are energized. The filament is selected to produce an electric field in the discharge region prior to initiation of arc discharge of at least 20 volts per centimeter. After an arc discharge is initiated, the voltage between the electrodes drops, and the filament is partially short-circuited by the arc discharge. The filament provides fast initial starting and fast hot restarting, while eliminating the requirement for high voltage starting pulses.

Abstract: In a gas turbine engine of the type wherein the fuel is injected through a pray injection nozzle into a combustion chamber, the improvement is a method and apparatus for modifying the characteristics of the fuel spray from the fuel injection nozzle so that fuels of higher aromatic content can be efficiently used in the engine. An electrode is disposed within the combustion chamber to provide a high strength electrostatic field in the vicinity of the injection nozzle so that the fuel spray from the nozzle becomes charged as it leaves the nozzle. The strength of the electric field is adjusted to provide a spray characteristic which produces optimum engine performance as determined by measuring an operating parameter of the engine such as the temperature of the gases exiting from the combustion chamber.

Abstract: A multistage EHD generator with parallel outputs to produce a usable output urrent. A single injector injects particles or droplets into a fluid flow which traverses a plurality of EHD generator stages in series. At each generator stage there is a means for charging the particles and a means for neutralizing the particles. The outputs between the charging and neutralizing means are connected in parallel to provide a substantial electrical power output.

Abstract: An optimally loaded electrohydrodynamic power generator which provides a form maximum loading throughout an EHD conversion channel. The channel between the injector and collector is in the form of a slender, converging-diverging nozzle of a shape defined by the following pair of parametric equations: ##EQU1## where r=nozzle radius at station z,r.sub.1 =nozzle radius at throat,.gamma.=ratio of specific heats,M=Mach number at station z,.lambda.=characteristic length,z=axial coordinate.

Abstract: A staircase electrode-wall configuration for a MHD generator which uses fd dynamic means to protect the electrodes from substantial damage due to arcing and chemical attack. The electrode walls of a MHD generator duct have periodic conductor/insulator elements where channel divergence or convergence is accomplished in a stepwise fashion. The electrode is situated within the insulator of each element to be backward-facing so as not to be directly exposed to the hot gas flow. The turbulence which exists at the backward-facing electrode moves the arc spot about the surface to prevent severe local damage. Chemical attack is inhibited by a laminated electrode surface of a low corrosive material and the turbulence which aids in cooling the electrode face. Additional cooling may be obtained by a purge jet at the electrode face.

Abstract: A practical charging mechanism for an electrogasdynamic spectral anemometer sing ultraviolet radiation. Ultraviolet radiation issues through windows in the wall of a test section through which flows a turbulent gas. The UV ionizes aerosol particles in the gas flow. A metallic rod which is connected to a high voltage source picks up ions of one polarity and a collector downstream neutralizes the ions of the opposite polarity. The current generated at the collector is measured and analyzed.