撞击流对喷雾燃烧强化机理的试验

Experiment on strengthening mechanisms of impinging streams on spray combustion

为了掌握液体燃料喷雾撞击燃烧过程中的关键影响因素及其影响规律,进而探索撞击流对喷雾燃烧的强化机理,搭建了喷雾撞击燃烧试验平台.利用数码摄像机、热电偶和红外热像仪分别记录火焰形态和温度分布,并对火焰形态参数和温度数据进行分析.结果表明:消耗相同燃料量时,双喷嘴喷雾撞击燃烧相比单喷嘴喷雾燃烧,火焰更加稳定,温度更高且分布更均匀;随着气相速度的增加,燃烧效率及撞击火焰区温度先升高后趋于稳定;随着空燃比的减小,燃烧效率先升高后降低,撞击火焰区温度先升高后趋于稳定;随着喷嘴间距的减小,燃烧效率及撞击区火焰温度先升高后降低;喷嘴夹角越接近180°,燃烧效率和火焰整体温度越高,撞击火焰区越稳定.

To grasp the key influence factors and influence rule during liquid fuel spray impinging combustion and to investigate the strengthening mechanisms of impinging streams on spray combustion,the spray impinging combustion experiment platform was designed and established.The flame shape was recorded by digital camera,and the flame temperature distribution was measured by thermocouple and infrared thermal imager.The images of flame shape and temperature data were analyzed.The results show that when the same amount of fuel is consumed,the opposed nozzle impinging flame is more stable,and the flame temperature is higher with more continuous distribution.With the increasing of gas velocity,the combustion efficiency and the temperature of impinging flame zone are increased with latter stable value.With the decreasing of air/fuel ratio,the combustion efficiency is increased with latter decreasing,while the temperature of impinging flame zone is increased with latter stable value.With the decreasing of nozzle spacing,the combustion efficiency and the temperature of impinging flame zone are increased with latter decreasing.The closer the nozzle angle is to 180°,the higher the combustion efficiency and the flame temperature are,and the more stable the impinging flame zone is.