本森灯火焰：示踪粒子法 CENTIMETER 《燃烧学基础》6，层流预混火焰 陈正(a@pku.edu.cm)23 本森灯火焰法 受拉伸 率影响 层流火 受热损 失影响 0.2 x.cm 《燃烧学基础》6，层流预混火焰 陈证(cz@pku.edu.cn)24
澦䏝ׁक澧 ͧࡗقஓ䍡 ୟࠔ I`&VQ[KJ[IT ࡄ८઼ठ͵䍥䍡ߺޯ 澦䏝ׁक澧 ͧࡗقஓ䍡 ୟࠔ I`&VQ[KJ[IT ࡄ䍥䍡ߺޯ ՈۿѴ տڦࢴ ܤՈ䏣 տڦס 䍡ࡗق څૻ ܤ䏣 䍡ࡗق څૻ
本森灯火焰法 (2) (b) d Le> Le=a D PCD 《燃烧学基础》6，层流预混火焰 s正zOpku.edu.cn)25 奇妙的本森灯火焰 Front View Top View Figure 10.9.1.Front and planar photographic images of a polyhedral rich propane-air flame. 《燃烧学基础》6，层流预混火焰 陈正(z@pku.edu.cn)26
澦䏝ׁक澧 ͧࡗقஓ䍡 ୟࠔ I`&VQ[KJ[IT ࡄ䍥䍡ߺޯ D C D Le P Le<1 Le>1 Le>1 Le<1 澦䏝ׁक澧 ͧࡗقஓ䍡 ୟࠔ I`&VQ[KJ[IT 䍥䍡ߺޯࣩײק
对型流火焰法 Laser Head Premixed fuel/air CCD Canera 2100 Processor 《燃烧学基础》6，层流预混火焰 陈正(z@pku.edu.cn)27 对型流火焰法：示踪粒子测速 1.01 S,=(S-2 →S,=U1 http://www.mae.case.edu/facilities/cdl/facilities/cflow 《燃烧学基础》6，层流预混火焰 陈证(cz@pku.edu.cn)28
澦䏝ׁक澧 ͧࡗقஓ䍡 ୟࠔ I`&VQ[KJ[IT ࡄ䍡ࡗֹت Premixed fuel/air 澦䏝ׁक澧 ͧࡗقஓ䍡 ୟࠔ I`&VQ[KJ[IT ૻ࡚८઼ठ͵ࡄ䍡ࡗֹت http://www.mae.case.edu/facilities/cdl/facilities/cflow SL U f S L (S U) n
对型流火焰法 U,<U<U 0 实验结果 线性拟合 200 300 Stretch Rate.a(s-1) 修正拉伸率的影响：线性拟合法(Wu&Law1984) http://ww.mae.case.edu/faciities/cdi/facilities/cfiow 《燃烧学基础》6，层流预混火焰 陈正a@pku.edu..cm29 Effects of flame stretch Stagnation surface Heat conduction d loss Heat diffusion Reaction zone Mass diffusion Mass diffusion pody gain Streamline d Control volume Le= Le<1,loss<gain,stronger flame,Tp>Tad PCD .Le>1,loss>gain,weaker flame,To<Tad 《燃烧学基础》6，层流预混火焰 陈正(z@pku.edu.cn)30
澦䏝ׁक澧 ͧࡗقஓ䍡 ୟࠔ I`&VQ[KJ[IT ࡄ䍡ࡗֹت ᇎ傼㔃᷌ 㓯ᙗᤏਸ ҒۿࠔѴڦࣩࢴտ 㓬܈՟ࡄ ]= 2G] U3 U2 U1 U1<U2<U3 http://www.mae.case.edu/facilities/cdl/facilities/cflow 澦䏝ׁक澧 ͧࡗقஓ䍡 ୟࠔ I`&VQ[KJ[IT +LLKIZYULLRGSKYZXKZIN dx dY D dx dT C D Le P Heat conduction Mass diffusion loss gain Le<1, loss<gain, stronger flame, Tb>Tad Le>1, loss>gain, weaker flame, Tb<Tad
Effects of flame stretch Stagnation surface -Heat diffusion Heat diffusion -Reaction zone -Mass diffusion Streamline K<0 K>0 Lose heat,gain mass 、/89 Lose mass,gain heat 1 Ka= -1)>0 stronger flame,Tp>Tad S016 Ka(Le -10<0 weaker flame,Tp<Ta 《燃烧学基础》6，层流预混火焰 陈正(z@pku.edu.cnm)31 Effects of flame stretch K>0 cmpee reaction) Le>1 e Le=1 incomplete reaction)】 Le<I U1<U2<U3 《燃烧学基础》6，层流预混火焰 29 Distance from Stagnation Surface
澦䏝ׁक澧 ͧࡗقஓ䍡 ୟࠔ I`&VQ[KJ[IT +LLKIZYULLRGSKYZXKZIN 0 ! 0 0 0 / Su f Ka 1) 0 1 ( ! Le Ka 1) 0 1 ( Le Ka stronger flame, Tb>Tad weaker flame, Tb<Ta Lose heat, gain mass Lose mass, gain heat ass 澦䏝ׁक澧 ͧࡗقஓ䍡 ୟࠔ I`&VQ[KJ[IT +LLKIZYULLRGSKYZXKZIN U3 U2 U1 U1<U2<U3 ! 0