Applied Physics B: Lasers and Optics   2016 年 122 卷 1 期

2016.01.01

Laser ablation plasma has been applied to assist stabilization of premixed methane/air flames with a flow speed up to 15.3??m/s. The ablation plasma was generated using the 50??Hz, 1064??nm output of a Nd:YAG laser onto a tantalum slab. With the ablation plasma, the stabilization equivalence ratio has been extended to the fuel-leaner end and the blow off limits have been enhanced by from 3.6- to 14.8-folds for flames which can stabilize without the plasma. The laser pulse energy required for flameholding was reduced to 10??mJ, a 64??% reduction compared with that of gas breakdown plasma, which will ease the demand for high-power lasers for high-frequency plasma generation. The temporal evolutions of the flame kernels following the ablation plasma were investigated using the OH* chemiluminescence imaging approach, and the flame propagation speed (v