The post-arc dielectric recovery in DC vacuum circuit breakers(VCBs) is crucial for successful current interruption. Previously

PIC(particle-in-cel) simulations focused on the sheath stage

simplifying atoms as background gas and neglecting metal vapor dissipation

with limited research on DC VCBs. This study employs the PIC method based on a typical DC interruption experiment

treating atoms as super-particles to simulate the continuous post-arc sheath and atom dissipation processes. The research compares two atom types including particles and background gas

finding minimal impact on simulation results. Treating atoms as background gas is reasonable to reduce computational costs. Furthermore

the reasonable agreement between simulated post-arc current and measured data confirms the method's applicability in the sheath stage. For the metal vapor dissipation

the influence of charged particles on this process was assessed through comparative analysis

showing that their effect is minor. Additionally

PIC simulation results closely match the predictions of the Rich-Farrall model

validating the effectiveness of the method for simulating vapor dissipation.