The role of air pressure in the variation of compound electric field due to negative corona discharge in a rod to plane electrode

The compound electric field distribution may vary at different air pressures. An electric field computing model in which the air pressure could be varied was built up to calculate the electric field under different applied voltages. The normal electric field was worked out by charge simulation (CSM) method. The continuity equations were solved by flux corrected transport (FCT) algorithm and the Poisson equation was computed by the successive over relaxation (SOR) method. The distribution of electrons, positive ions and negative ions was analyzed, which could influence the compound electric field. The electric field under different applied voltages at various air pressures were computed. The strengthened degree of electrical field between streamer and plane is weaker due to the decrease of atmosphere pressure. The electric field strength at 0.05 MPa is about 55% of the electric field strength at 0.1 MPa. The relationship between the maximal values of electric field ahead of the streamer under different applied voltages and the air pressure was acquired.