Experimental study on electrostatic–plasma interaction in an inductively coupled plasma environment relevant to hypersonic flight

The interaction between the vehicle's electrostatic accumulation and the plasma in hypersonic flight environments has received little attention. To investigate this mechanism, an inductively coupled plasma (ICP) system was employed to generate plasmas with plasma densities up to 10¹⁷m⁻³ and electron temperatures of several eV, replicating key characteristics of hypersonic plasmas. Using this platform, the interactions of metallic and dielectric targets with the plasma were systematically examined. The results show that positively charged metallic targets significantly enhance local plasma density by up to 180 % via electrostatic attraction. However, negatively charged metallic targets reduced plasma density due to electric field repulsion, followed by a subsequent increase attributed to secondary electron emission from positive ion bombardment. The motion of charged particles induced measurable currents at the milliampere level in the circuit. In contrast, dielectric targets accumulate surface charge that effectively suppresses electric-field penetration and produces negligible influence on the adjacent plasma. These observations illustrate how electrostatic potentials modify the dynamics of charged-particle near different materials and provide useful guidance for electrostatic protection and flight safety considerations in hypersonic vehicles.