天然气预混湍流燃烧特性的实验

为了获得天然气的预混湍流燃烧特性，在湍流燃烧弹中对天然气在当量比范围为0.7～1.4、初始压力范围为0.1～0.3 MPa、初始温度范围为300～400 K、湍流强度范围为1.0～2.7 m/s条件下的预混湍流燃烧火焰发展特性进行了试验测试，并分析了当量比、湍流强度、初始温度、初始压力对天然气湍流火焰传播速度、火焰褶皱比以及湍流燃烧速度的影响。结果表明：湍流火焰传播速度随着当量比的升高先增加再降低，在当量比为1.1时达到最大，并且随湍流强度与初始温度的升高而升高，但随初始压力的升高变化不明显。火焰褶皱程度随湍流强度与初始压力的升高或当量比与初始温度的降低而逐渐增强。湍流燃烧速度随当量比的升高先升高后下降，在当量比为1.1时达到最大，并且随湍流强度、初始温度与初始压力的升高而逐渐升高。

Experiment on premixed turbulent combustion characteristics of natural gas

In order to gain the premixed turbulent combustion characteristics of natural gas, the premixed turbulent combustion flame propagation characteristics of natural gas at the conditions of the equivalence ratios range of 0.7?1.4, the initial pressures range of 0.1?0.3 MPa, the initial temperatures range of 300?400 K, and the turbulence intensities range of 1.0?2.7 m/s were experimentally tested in the turbulent combustion bomb. Furthermore, the influences of equivalence ratio, turbulence intensity, initial temperature, and initial pressure on the turbulent flame propagation speed, flame wrinkle ratio and turbulent combustion speed of natural gas were investigated. The results showed that the turbulent flame propagation speeds of natural gas increased and then decreased with the increase of equivalence ratio, and reached the maximum at equivalence ratio of 1.1. With the increase of turbulence intensity and initial temperature, the turbulent flame propagation speed gradually increased. However, with the increase of initial pressure, the turbulent flame propagation speed varied slightly. With the increase of turbulence intensity and initial pressure, or the decrease of equivalence ratio and initial temperature, the flame wrinkle ratio gradually increased. With the increase of equivalent ratio, the turbulent combustion speeds increased first and then decreased, and reached the maximum at equivalent ratio of 1.1. With the increase of the turbulence intensity, initial temperature and pressure, the turbulent combustion speeds gradually increased.