The effect of hydrogen addition on the flame behavior of a non-premixed oxy-methane jet in a lab-scale furnace

Flame chemiluminescence in premixed combustion of hydrogen-enriched fuels

“…2 shows the emission spectra of flames with different hydrogen contents at different equivalence ratios. The experimental results demonstrate that the addition of hydrogen causes a visible reduction of the general intensity level, which is in agreement with previous works [8,35,37].…”

“…On the one hand, according to Oh et al [37], although hydrogen addition is expected to promote faster reactions which causes an increase in local OH*, the total intensity of OH* is expected to decrease, since the CH molecule has an important role on OH* formation through the reaction [13,39]:…”

“…On the other hand, besides their intrinsic interest, CH 4 eH 2 blends can be considered as a first approach to the characterization of syngas flames, since the influence of fuel composition on flame behavior has been demonstrated to be largely determined by the proportion of hydrogen in the syngas [2,26,27,30e33]. Some authors have analyzed the effect of hydrogen addition on chemiluminescence both in premixed [8,28,34e36] and non-premixed flames [35,37] with the aim of describing the behavior of hydrogen-enriched fuels. All previous works agree that OH* is the main emitter in hydrogen flames and therefore, OH* emission in the ultraviolet region has been the focus of most of these works.…”

Influence of fuel composition on chemiluminescence emission in premixed flames of CH4/CO2/H2/CO blends

“…However, the variations in the flame spectrum are evident. On the one hand, as it happened in hydrogen enriched flames [34], as the percentage of CH 4 decreases, there is a clear reduction of the peak associated with OH*; this is attributed to the diminished presence of CH molecules, which play an important role in OH* formation [23,34,40]. In addition, despite having some Fig.…”

Extinction limits and structure of counterflow nonpremixed hydrogen-doped ammonia/air flames at elevated temperatures

“…It is not practical to burn NH 3 alone because of its low burning intensity and high ignition energy, but these problems can be resolved if H 2 is added to NH 3 . Actually, H 2 has been used as an additive or a blend for hydrocarbon fuel, e.g., CNG and H 2 blends in spark-ignition engines [7], nonpremixed H 2 -methane (CH 4 )/N 2 -oxygen (O 2 ) flames [8] and H 2 -added CH 4 eO 2 jet flames [9].…”