Air ionization in self-neutralizing air-breathing plasma thruster

Abstract

The paper describes an arc electron source for air ionization applications in a self-neutralizing air-breathing plasma thruster. The arc electron source is an electron source with a prominent level of electron energy control that is required for the air-breathing plasma thruster. The mean energy of the electrons in the arc electron source is controlled by changing the grid voltage in the range of 0 V–300 V. The Langmuir/Faraday probes were used to obtain ion/electron current, electron temperature, and electron density as a function of pressure and electron energy. Ion current measurements concerning distance from the source were obtained as a function of pressure and grid voltage. Optical emission spectroscopy was used to obtain electron temperature, spectral intensities, and ion formation rate. Additionally, a drift tube based on radial magnetic field electron confinement was designed to detect the presence of negative ions. It has been shown that both positive and negative ions can be produced thus providing conditions for a self-neutralizing air-breathing plasma thruster.

Side Feeding Mechanism for Micro Cathode Arc Thruster

“…The magnetic field enhances the performance and efficiency of the thruster due to the increase in the rate of ionization. This paper discusses the characterization of SF-µCAT using various plasma diagnostic methods mentioned in Fig 2 . It shows the schematics for the system design configuration starting with an inductive energy storage PPU (power-providing unit) circuit [29] to power the thruster. The circuit comprises a 550µH inductor, an IXYH50N120C3D1 Insulated Gate Bipolar Transistor (IGBT), a 6800 μF capacitor, an input DC voltage in the range of 20-30V, and a pulse width modulation (PWM) of 750 μs operating at 5 Hz frequency.…”

“…The thruster is strategically positioned at a distance from the center of the magnet such that the plasma plume can experience a maximum of 0.5T magnetic field. This magnetic field efficiently bends and directs the plasma in the -J × B direction, thereby enhancing the ionization rate and increasing the plasma density and ion velocity [29]. In the context of VATs, arc current refers to the current between the anode and cathode at the point of discharge.…”

“…a) Side view and isometric view illustration of SF-CAT explaining the formation of plasma and the cathode spot as previously shown[29]. (c) Solidworks assembly of the SF-CAT featuring the sping-based feeding mechanism for the propellant.…”