Performance and supersonic ion beams of the ALPHIE (Alternative Low Power Hybrid Ion Engine) plasma thruster.

The Alternative Low Power Hybrid Ion Engine (ALPHIE) is a newly patented throttleable gridded plasma thruster [1]. Its design is small in size and different from the classical gridded configuration (Kauffman) and shares elements of Hall effect and Multi-Cusped field thrusters [1,2].

The thruster performance will be discussed on the basis of laboratory experiments [2] and PIC simulations [3]. The supersonic ion beams in its plasma plume exhaust have been characterized by means of movable electric probes [3]. Figures show the ion velocity distribution functions (IVDFs) at a fixed point along the plasma plume symmetry axis. The two-peaked IVDFs show the mesothermal plasma flow where fast (supersonic) ions move at 40-60 km/s speeds. These are controlled by the throttle potential V_ACand the propellant gas flor rate Q. Numerical calculations show that suprathermal ion beam formation depends on both Q and V_AC. Finally, the thrust levels, specific impulses and ion production rates will be discussed on the basis of laboratory tests.

The IVDF for different mass flow rates Q with a fixed acceleration Fig. 2: The IVDF for different acceleration voltages holding fixed the mass flow rate Q.

[1]L. Conde , J. L Domenech-Garret, J. M. Donoso, E. Del Río and M. A. Castillo. Plasma accelerator with modulated thrust. US Pat. 10172227B2 (2019). European Patent Office EP3369294 and PCT/EP2015/074879 (2015).

[2] L. Conde, J.L. Domenech-Garret, J.M. Donoso, J. Damba, S.P. Tierno, E. Alamillo-Gamboa and M. A. Castillo. Phys. Plasmas, 24, (12) 123514-1,8 (2018).

[3] J. González and L. Conde, .Phys. Plasmas, 26, (4) 043505-1,6 (2019).

[4] J. Damba, P. Argente, P.E. Maldonado, A. Cervone, J.L. Domenech-Garret and L. Conde. J. Phys. Conf. Ser. 958, 012002-1, 9 (2017)