0 引言
1 实验系统
1.1 实验装置及火焰工况
Fig. 1 Schematic diagram of experimental setup图1 实验系统简图 |
Table 1 Cases of C2H4/air flat flames表1 实验火焰工况 |
工况 | 燃料当量比 Φ | 混合气流速 Umix / (m/s) | 流量Q / (L/min) | |
---|---|---|---|---|
C2H4 | 空气 | |||
火焰 1 | 2.20 | 0.07 | 1.59 | 10.29 |
火焰 2 | 2.25 | 0.07 | 1.62 | 10.26 |
火焰 3 | 2.30 | 0.07 | 1.65 | 10.23 |
火焰 4 | 2.35 | 0.07 | 1.68 | 10.20 |
火焰 5 | 2.40 | 0.05 | 1.22 | 7.26 |
火焰 6 | 2.40 | 0.06 | 1.46 | 8.71 |
火焰 7 | 2.40 | 0.07 | 1.71 | 10.17 |
火焰 8 | 2.50 | 0.05 | 1.26 | 7.22 |
火焰 9 | 2.50 | 0.06 | 1.52 | 8.66 |
火焰 10 | 2.50 | 0.07 | 1.77 | 10.11 |
火焰 11 | 2.60 | 0.05 | 1.31 | 7.18 |
火焰 12 | 2.60 | 0.06 | 1.57 | 8.60 |
火焰 13 | 2.60 | 0.07 | 1.83 | 10.05 |
1.2 热电偶扫描子系统
Fig. 2 SEM photograph of R-type thermocouple图2 R型热电偶扫描电镜照片 |
2 热电偶测温修正
2.1 炭烟火焰的热电偶测温特性
Fig. 3 Temperature curve measured by thermocouple in C2H4/air flat soot flames (at HAB = 14.5 mm with Φ = 2.3 and Umix = 0.07 m/s)图3 平面炭烟火焰中热电偶测量温度特性 |
2.2 温度测量修正方法
Fig. 4 R-type thermocouple coated by soot particles图4 被炭烟包裹的R型热电偶 |
2.3 温度测量修正结果
Fig. 5 Corrected and uncorrected temperature measured by thermocouple in soot flames图5 热电偶测量炭烟火焰的原始温度与修正温度 |
2.4 与文献测量结果的对比
Fig. 6 Comparisons of measured temperature by different methods图6 不同测量方法的温度测量结果对比 |
3 平面炭烟火焰温度场测量
3.1 火焰中心区域温度特性
Fig. 7 (a) Temperature distribution along axial direction under different equivalence ratios; (b) temperature distribution along radial direction under different equivalence ratios at HAB = 14.5 mm; (c) temperature distribution along radial direction under different mixture velocities at HAB = 14.5 mm图7 (a)不同当量比条件下火焰轴线上温度分布;(b)HAB = 14.5 mm处不同当量比条件下火焰沿半径方向的温度分布;(c)HAB = 14.5 mm处不同出口流速时火焰沿半径方向的温度分布 |
3.2 火焰边缘温度波动特性
Fig. 8 Raw temperature data measured by thermocouple under different equivalence ratios at HAB = 14.5 mm: (a) temperature fluctuation characteristics in the outside edges of soot flat flames; (b) local fluctuating temperature图8 HAB = 14.5 mm处热电偶测量的不同当量比时火焰的原始温度:(a)平面炭烟火焰边缘处的温度振荡特性;(b)局部温度振荡 |
Fig. 9 Raw temperature data measured by thermocouple under different premixed gas velocities at HAB = 14.5 mm: (a) flame temperature fluctuation characteristics; (b) local fluctuating temperature图9 HAB = 14.5 mm处热电偶测量的不同流速火焰的原始温度:(a)火焰的温度振荡特性;(b)局部温度振荡 |