The effect of millisecond wide sub-breakdown pulsed voltage-current induced flow perturbation has been measured in premixed\nlaminar atmospheric pressure propane/air flame. The flame equivalence ratios were varied from 0.8 to 1.2 with the flow speeds\nnear 1.1meter/second. Spatio-temporal flame structure changes were observed through collection of CH (A-X) and OH (A-X)\nchemiluminescence and simultaneous spontaneous Raman scattering from N2. This optical collection scheme allows us to obtain a\nstrong correlation between the measured gas temperature and the chemiluminescence intensity, verifying that chemiluminescence\nimages provide accurate measurements of flame reaction zone structure modifications. The experimental results suggest that the\nflame perturbation is caused by ionic wind originating only from the radial positive space-charge distribution in/near the cathode\nfall. A net momentum transfer acts along the annular space discharge distribution in the reaction zone at or near the cathode fall\nwhich modifies the flow field near the cathodic burner head. This radially inward directed body force appears to enhance mixing\nsimilar to a swirl induced modification of the flame structure. The flame fluidic response exhibit a strong dependence on the\nvoltage pulse width =10 millisecond.
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