A Huygens immersed-finite-element particle-in-cell method for modeling plasma-surface interactions with moving interface

•This article is the first work to propose a Huygens Immersed-Finite-Element Particle-In-Cell (IFE-PIC) method, which is efficient and accurate to simulate the plasma-surface interactions with moving interface on Cartesian meshes.•The PIC method is mainly responsible for the plasma simulation, the IFE method is mainly responsible for solving the governing interface equation on Cartesian mesh, and the Huygens wavelet method is mainly responsible for the surface evolution. The proposed iterative method naturally combines the Huygens wavelet method, the IFE method, and the PIC method into a dynamic system by fully utilizing their advantages and inherent relationships: at each iteration step, the PIC method provides the charge information to the IFE method and the incident information to the Huygens method; the IFE method provides the current polyline approximation of the interface to the Huygens method; then the Huygens method provides the new polyline approximation of the interface back to the IFE method; and the IFE method provides the new electric field back to the PIC method for the next iteration step.•The two numerical experiments, the evolution of a sphere with given surface evolution rate and the erosion of Hall thruster channel wall, validate the proposed method and illustrate its features and applicability to the plasma-surface interactions with moving interface. Surface evolution is an unavoidable issue in engineering plasma applications. In this article an iterative method for modeling plasma-surface interactions with moving interface is proposed and validated. In this method, the plasma dynamics is simulated by an immersed finite element particle-in-cell (IFE-PIC) method, and the surface evolution is modeled by the Huygens wavelet method which is coupled with the iteration of the IFE-PIC method. Numerical experiments, including prototypical engineering applications, such as the erosion of Hall thruster channel wall, are presented to demonstrate features of this Huygens IFE-PIC method for simulating the dynamic plasma-surface interactions.