Experimental estimation of the combustion regime in the oil-gas explosion process
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摘要: 首先分析讨论了油气爆炸过程中火焰燃烧模式的估计方法,然后在激波管内进行了低、中、高3次不同初始油气浓度条件下的油气爆炸实验,通过实验数据分别计算出了低、中、高初始油气浓度条件下油气爆炸在初期、中期和后期的丹姆克尔数和湍流雷诺数,最后依靠丹姆克尔数-湍流雷诺数图对低、中、高初始油气浓度条件下油气爆炸初期、中期和后期的火焰燃烧模式进行了定量估计。结果表明:低、中、高初始油气浓度条件下激波管油气爆炸过程初期、中期和后期的火焰燃烧模式均为漩涡内小火焰模式。Abstract: In this artical, firstly, estimation method of flame combustion regime of the oil-gas explosion was discussed and three oil-gas explosion experiments under the conditions of low, middle and high initial gas vapor concentration were carried out, and then the Damköhler number and the turbulent Reynolds number for the early, interim and late stage of the oil-gas explosion at low, middle and high initial gas vapor concentration conditions were calculated according to the experimental data. Finally, through the Damköhler number vs. Reynolds number diagram, the combustion regimes for each stage of the oil-gas explosion at low, middle and high initial gas vapor concentration conditions were quantitative estimated. Results show that the combustions at early, interim and late stage of the gas-air explosion under the conditions of low, middle and high initial gas vapor concentration in the tube have the same regime of flameletes-in-eddies. The conclusions of this paper can provide some useful reference for the further study of combustion regime and the numerical analysis model selection of the gas-oil explosion.
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表 1 各时刻激波管内气体流速、压力和已燃气体温度实验数据(ϕ=1)
Table 1. Flow velocity, pressure and burned gas temperature in the shock tube at different times (ϕ=1)
t/ms v/(m·s-1) vrms* p/Pa Tmax/K 50 55.82 34.62 98 530 1 127.39 150 72.76 51.56 340 800 1 203.62 250 29.14 7.94 486 190 1 324.05 表 2 参数BM,B2和ϕM取值
Table 2. Value of BM, B2 and ϕM
燃料 ϕM BM/(cm·s-1) B2/(cm·s-1) 甲醇 1.11 36.92 -140.51 丙烷 1.08 34.22 -138.65 异辛烷 1.13 26.32 -84.72 RMFD-303 1.13 27.58 -78.34 表 3 各时刻的Da和Rel0计算值(ϕ=1)
Table 3. Calculated values of Da & Rel0 at different times (ϕ=1)
t/ms Da Rel0 50 0.19 4 603 150 0.26 31 366 250 21 4 012 表 4 各时刻激波管内气体流速、压力和已燃气体温度实验数据(ϕ=0.72)
Table 4. Flow velocity, pressure and burned gas temperature in the shock tube at different times (ϕ=0.72)
t/ms v/(m·s-1) vrms* p/Pa Tmax/K 50 65.13 45.45 115 120 1 158.42 150 -5.74 25.42 322 410 1 201.77 250 11.04 8.64 357 380 1 238.51 表 5 各时刻激波管内气体流速、压力和已燃气体温度实验数据(ϕ=1.28)
Table 5. Flow velocity, pressure and burned gas temperature in the shock tube at different times (ϕ=1.28)
t/ms v/(m·s-1) vrms* p/Pa Tmax/K 50 29.69 7.10 11 510 1 251.63 150 86.91 64.32 227 780 1 296.15 250 12.64 9.95 504 310 1 357.36 表 6 各时刻的Da和Rel0计算值
Table 6. Calculated values of Da & Rel0 at different times
t/ms Da Rel0 ϕ=0.72 ϕ=1.28 ϕ=0.72 ϕ=1.28 50 0.03 1.31 6 767 93 150 0.10 0.15 9 993 15 838 250 0.31 1.76 3 589 4 970 -
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