添加CO₂对密闭空间氢气-空气湍流混合气 爆炸燃烧特性的影响

To investigate the performance of CO₂as a flame suppressant in practical hydrogen deflagration scenarios, experiments are conducted in a constant-volume combustion chamber to study the explosion and combustion characteristics of H₂-air-CO₂turbulent mixtures with varying CO₂fractions in a confined space. Explosion combustion parameters are obtained, and the effects of CO₂concentration and turbulence intensity are systematically analyzed. An empirical formula linking the deflagration index to pressure rise time is established. The results show that increased CO₂fraction reduces both flame propagation speed and total mixture energy, leading to significant decreases in explosion pressure and pressure rise rate. When CO2 fraction increases from 0% to 30%, explosion pressure decreases by 32. 6%, and maximum pressure rise rate decreases by 77. 7%. Heat loss remains largely unchanged, resulting in negligible variation between adiabatic pressure and experimental maximum explosion pressure. Under constant equivalence ratio and CO₂fraction, increased turbulence intensity has little effect on maximum explosion pressure, while the maximum pressure rise rate increases significantly, and heat loss decreases, reducing the difference between adiabatic pressure and experimental maximum explosion pressure. For example, at an equivalence ratio of 1.0 and CO₂fraction of 30%, as turbulence velocity increases from 0 to 2.715 m/s, maximum pressure rise rate increases by 179%, and the difference between adiabatic pressure and experimental maximum explosion pressure decreases by 7.2%.