Cyclic Endurance Test of an Ammonia Arcjet for ELITE/STAR
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Performance of a hydrogen radiation-cooled arc jet engine, with emphasis on power conversion efficiency and the energy addition and loss mechanism
Arc jet engine, lifetests, and pulsed performance
Mixing of subsonic argon arc jet with coaxial flow of cold helium in duct studied by schlieren photography, calorimetry, and sampling probe
Magnetoplasmadynamic arc jet thrustor
Critical mass flow rate existence for maximum thrust from MPD arc jet
Arc jet exhaust velocity compared with propagation velocity of random light fluctuations
Photographic spectra of ablating plastics in thermodynamic environments related to species and temperatures in boundary layers
Local mass flux and local impact pressure measurement in arc jet exhaust flow fields
Probe for total enthalpy measurements in arc jet exhausts
Surface parameters influence on energy transfer to arc jet anode, discussing work function, accommodation coefficient and diffuse reflection coefficient of electrons
Surface parameters influence on energy transfer to arc jet anode, discussing work function, accommodation coefficient and diffuse reflection coefficient of electrons
Arc luminosity in cathode region of quasi-steady MPD arc jet, using high speed photography and electric and magnetic field probes
Closed form formula for plasma thrust from arc jets with self induced magnetic fields, predicting electrode erosion and entrainment
Voltage fluctuations in a multi-megawatt quasi-steady MPD accelerator, indicative of increased ablation and a consequent degradation in performance, are found to exist only over a narrow range of currents, above which the ablation continues. Within this range, the discharge is characterized by a thin cylindrical shell, 4.0 cm in diameter, concentric with the cathode surface, containing steep radial gradients in plasma luminosity, number density, current density, electric field and Hall parameter, and within which a significant fraction of the propellant is first ionized. Experiments have shown that this cylindrical shell can be totally eliminated by immersing a small object at critical locations within it, thereby increasing the local mass density by preferential ablation and suggesting further means of improving the accelerator design.
The performance of quasisteady multimegawatt MPD thrusters is significantly affected by anode thickness, location, and orifice radius, and by cathode length. Terminal voltage oscillations and electrode erosion are deferred until higher currents by anodes at more downstream locations and of smaller orifice radius and by cathodes of greater length. Without an optimized geometry, specific impulses of 3300 s and thrust efficiencies up to 31% are implied by the best data.