Relationship between ionization current in post-flame and temperature around electrodes

Experiment on ionization current and flame development were investigated in a constant volume combustion bomb, and the relationship between temperature around electrodes and ionization current in post-flame zone were studied based on AVL-FIRE simulation. Results show that the current has three phases reflecting spark ignition, front-flame and post-flame when using the ignition electrodes as detecting electrode. However, when ignition electrodes and detecting electrodes are separated, the current shows two phases reflecting partial front-flame and post-flame. The current in the post-flame zone appears at the temperature about 2000 K for different electrodes location. With the increase of the distance between ignition electrodes and detector electrodes, the current and temperature at the electrodes gap are decreased. A linear relationship between temperature and current is presented when temperature is over 2000 K.