The flow fields were measured for the stretched cylindrical premixed flame and the counterflow twin flames with stoichiometric methane-air mixtures using LDV. A quantitative comparison of the flow structure was made based on the actual velocity gradients and flame stretch rates. The similarity between the flow structures for both flame types was clarified over a wide range of velocity gradients. The extinction characteristics were compared with each other and it was shown that the cylindrical flame was extinguished at a lower velocity gradient and a lower stretch rate than the twin flames. The flame diameter of the cylindrical flame at the state of flame extinction was larger than the flame distance for the twin flames. The mechanism behind these characteristics was discussed from the view point of investigating the effects of high curvature on the extinction for highly stretched flames.
ASJC Scopus subject areas
- Chemical Engineering(all)
- Fuel Technology
- Energy Engineering and Power Technology
- Physics and Astronomy(all)