Experimental study on influence of electrode geometrical parameters on ionization current

The influence of electrodes on ionization current generated during the combustion of compressed natural gas (CNG)/air mixture was experimentally studied in a constant volume combustion bomb. In addition, the schlieren pictures taken by a high-speed camera were compared with the corresponding ionization currents. The results show that the electrode diameter and the area of the disks arranged on the electrode do not affect the profiles of the ionization current curves. All the curves include the information of the ignition, the front-flame and the post-flame stages which fully reflect the main combustion process. However, the values of the ionization current are affected by the electrode geometrical parameters, and the anode area has more influence on the ionization current than the cathode area.