Two dimensional studies of Trichel pulses in air using the finite element method

The formation of Trichel pulses using two dimensional axisymmetric finite element (FE) simulations is presented in this paper. The hydrodynamic drift-diffusion approximation is used to model the phenomenon and the simulation is based on solving the coupled system of partial differential equations accounting for the transport of charged particles and Poisson´s equation for the electric field. A needle-plane geometry with an air gap and constant negative step voltage is analysed at atmospheric pressure. The charge distributions and electric field variations during the formation of the first pulse are studied in detail. Factors influencing the first pulse shape, frequency and magnitude of subsequent Trichel pulses, namely the secondary emission coefficient and applied voltage, are also investigated.