初始压力对氢-空气预混诱导湍流燃烧的影响

Effect of Different Initial Pressures on Induced Combustion Characteristics of Hydrogen-Air Pre-Mixture

在顶置点火定容燃烧弹内加入一个网孔板,采用纹影法和压力采集系统,研究不同初始压力下氢气-空气预混合气穿过网孔时的火焰传播特性以及压力特性.结果表明:火焰通过网孔板时产生射流,网孔间火焰相互干涉,火焰前锋面积增加,诱导成湍流燃烧;相对于未添加网孔板而言,最大燃烧压力值几乎不变,达到最大压力的时刻提前,燃烧持续期缩短;火焰穿过网孔板后,传播速度提高,压力升高率增加;随着初始压力的增加,添加网孔板后的燃烧持续期变化率先增大后减小,在初始压力为0.10,MPa时达到最大值.

A mesh plate was set in the upper part of constant volume combustion chamber, and schlieren method and pressure acquisition systems were used to analyse flame propagation characteristics and pressure characteristics when hydrogen-air pre-mixture flame traverses mesh plate under different initial pressures. Experimental results show jet stream when hydrogen-air pre-mixture flame traverses the mesh plate, and the flame among mesh is interfered mutu- ally. The flame-front area increases and flame is induced into the turbulent combustion. Maximum explosion pressure before and after adding the mesh plate do not change. Addition of mesh plate will advance the time of maximum pres- sure arriving and shorten the combustion duration. After flame passes through the mesh plate, propagation velocity and pressure rising rate increase simultaneously. With the increase of initial pressure, the change rate of combustion duration after adding mesh plate increases first and then decreases, and gives its maximum at initial pressure of 0.10 MPa.