Nj. Wood et al., CHARACTERIZATION OF A LOW-POWER STEADY-STATE MAGNETOPLASMADYNAMIC DEVICE FOR NON-PROPULSIVE APPLICATIONS, Plasma sources science & technology, 6(4), 1997, pp. 484-491
The design, construction and operation of a low-power (5-15 kW) steady
-state magnetoplasmadynamic (MPD) device is described. Its performance
when operated on argon, nitrogen and oxygen-bearing gases is detailed
, and typical operational data for runs with argon given, together wit
h a current-voltage characteristic for the device. The electrode suppo
rts are water cooled; water temperature measurements show that thermal
equilibrium is reached, thus enabling the anode and cathode power sin
ks to be determined and the device efficiency to be estimated. These f
igures are similar to those obtained from another device also operated
in the tens of kilowatts power range. Electrode erosion and passivati
on mechanisms encountered in the device are described for the differen
t propellants. Analysis of the cathode shows that the majority of the
erosion occurs at the relatively cool cathode root and backplate. Pass
ivation of the actively cooled anode due to deposited layers, when ope
rated on oxygen-bearing gases, is discussed. Non-propulsive applicatio
ns of such an MPD device for materials processing or for atomic oxygen
production are discussed, together with proposed modifications to len
gthen run times.