预混式燃烧腔内混合及燃烧特性研究

Study on mixing and combustion characteristics in premixed combustion chamber

中文关键词: 预混  混合特性  火孔角度  燃烧特性

英文关键词: Premixed, Mixing characteristics, Fire hole angle, Combustion characteristic

中文摘要:

      以预混式燃气灶为研究对象，采用数值模拟的方法对燃气灶进行冷态模拟与燃烧模拟。冷态模拟对比分析不同结构对燃气灶内组分分布的影响，燃烧模拟研究火孔角度等参数对燃烧火焰的影响。建立内部结构不同的两种混合腔，高度始终为47 mm，空气入口速度为1 m/s，甲烷入口速度为5 m/s。冷态模拟结果表明，适当减小混合腔收缩段长度，增加扩张段长度有利于混合气在混合腔内的混合，缩放结构混合腔较背压结构混合效果提升了15%；燃烧模拟结果表明，相同边界条件下，火焰高度、烟气温度波动范围随火孔角度的增加而增大，火焰宽度随着角度的增大而减小，该模型理想火孔角度为70°。

英文摘要:

      The premixed gas stove is chosen as the research object and the cold state and combustion simulation are carried out by numerical simulation method. The effects of different structures on the distribution of components were compared and analyzed in cold state simulation, and the effect of orifice angle on combustion flame was studied in combustion simulation. Two kinds of mixing chambers with different internal structures were established, and the height was always 47mm, and the air inlet velocity was 1m/s, the methane inlet velocity was 5m/s. The cold state simulation results show that appropriately decreasing the length of the contraction section and increasing the length of the expansion section are beneficial to the mixing. After optimization, the mixing effect of the mechanism is improved by 15%. The simulation results show that, under the same boundary conditions, the flame height and flue gas temperature fluctuation range increase with the increase of the fire hole angle, while the flame width decreases with the increase of the fire hole angle. The ideal fire hole angle of this model is 70°.