不同位置电极附近温度与焰后区离子电流的关系

Relationship Between Ionization Current in Post-Flame and Temperature Around Electrodes

在定容燃烧弹中不同位置布置测量电极进行了离子电流与火焰发展的试验研究,应用AVL-FIRE软件研究了电极附近温度和焰后区离子电流间的关系.结果表明:当采用点火电极测量时,离子电流包括点火、火焰前锋区与焰后区三个阶段;当测量电极与点火电极分开时,离子电流只有部分火焰前锋区与焰后区.不同位置测量的离子电流焰后区信号开始出现时所对应温度值均在2,000,K左右;随着测量电极与点火电极间距的增加,电极附近温度依次降低,离子电流焰后区信号亦逐渐降低.焰后区离子电流随着温度的升高而增加,二者基本呈线性关系.

Experiment on ionization current and flame development were investigated in a constant vol-ume 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 detect-ing 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 2,000,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 de-creased.A linear relationship between temperature and current is presented when temperature is over 2 000 K.