Research on the Gradient-Field Superconducting Magnet for Magnetoplasmadynamic Thruster Performance Improvement

Magnetoplasmadynamic thrusters (MPDTs) are characterized by their high specific impulse, high thrust, and long operational life. Hence, they are promising candidates as space electric thrusters for deep space exploration, such as for future interstellar voyages. To improve the performance of MPDTs, this article investigates the potential to enhance their plume performance using a high-gradient magnetic field based on superconductor technology. We introduce a high-intensity superconducting magnetic field constraint method based on a 100-kW MPDT, which involves making the solenoid and gradient-field superconducting magnets more compact. The central magnetic field can reach 1 T and the magnetic field homogeneity is optimized from 1.69% to 0.83%. In addition, the MHD method is used to simulate and verify the concentration-constrained acceleration of plasma by the gradient-field superconducting magnets. Experimental results show that with increases in magnetic field strength, the axial plasma plume becomes more concentrated. The plume distribution of the 100-kW gradient-superconducting MPDT is more uniform than that of a solenoid plume at the same discharge current due to better magnetic field homogeneity.