基于静态混合器的预混阵列微管纯氢燃烧研究

In order to help achieve the “carbon peaking and carbon neutrality goals” and realize the zero carbon emission of pure hydrogen combustion in gas turbines，a premixed micro-tube burner based on a static mixer was designed to meet the requirements of low emission of pure hydrogen combustion. Under the conditions of normal temperature and pressure， 23.7， 47.3， 71.1 m³/h air flow， the pure hydrogen combustion test was carried out on the 4×4 array of premixed micro-tube burner，with the equivalent ratio ranging from 0.25 to 0.85. The time-average macro flame image was obtained，the NOx emission was measured， the combustion oscillation characteristics in the chamber were measured with a pressure pulsation sensor，and the combustion characteristics of pure hydrogen combustion under different air flows and equivalent ratios were explored. The hydrogen-air mixing in the array micro-tube was analyzed with Fluent software. The results showed that when the equivalent ratio was within 0.7，the volume fraction of NOx emission of the burner under various conditions was within 20×10⁻⁶. The micro-mixing flame was similar to the pure premixed flame. With the increase of air flow，the velocity of the micro-tube nozzle increased，the overall length was stretched，and the flame cone angle became smaller. When the air flow was 23.7 m³/h and the equivalent ratio was less than 0.55，stable hydrogen combustion can be achieved. In other conditions，the starting point of the vibration moved forward with the increase of air flow. With the increase of the equivalent ratio，the amplitude of combustion oscillation first increased and then showed a trend of fluctuation decrease. The oscillation frequency was generally above 700 Hz， and steadily increased with the increase of the equivalent ratio.