旋流预混预蒸发装置蒸发和排放特性

Vaporization and discharge characteristics of lean premixing prevaporizing system

采用数值模拟和试验两种方法获得了两种结构的贫油预混预蒸发装置(Lean premixing and prevaporizing system,简称LPP)出口的油气混合均匀性,并采用单管燃烧室验证了LPP装置的燃烧特性.径向旋流预混装置出口的油气混合比轴向旋流预混装置更均匀;旋流器的叶片数和旋流角、预混管长度、气流速度、喷油方式等对油气混合均匀性均有比较显著的影响;在当量比高至0.5左右时,LPP燃烧室NOX和CO排放比传统燃烧室低得多;只要LPP装置出口存在回流,燃烧时就会出现回火现象.

Fuel-air mixture uniformity for two sets of lean premixing and prevaporizing system（LPP） was obtained numerically and experimentally, and the combustion characteristics of LPP were verified with a tubular combustor. The results show that, there is a better fuel-air mixture uniformity at the exit of radial swirler premixing facilities than at axial ones. Vane number and swirl angle of a swirler, premixing distance, air velocity and fuel injection methods, etc, have remarkable effects on air-fuel mixture uniformity. When fuel-air equivalent ratio is bigger than 0.5, CO and NOx emissions of the LPP combustor are significantly lower. In the event of presence of backflow at a LPP facility exit, the flashback takes place during combustion.