The conditions most favorable for vortex pairing in the near field of a circular jet have been investigated through hot-wire measurements in two circular air jets subjected to controlled excitation. Two distinct modes of vortex pairing, inferred from the subharmonic spectral component of the u-signal, have been identified. The first mode is attributed to the exit shear layer instability which scales on the exit free shear layer width, and the second (jet) mode scales on the jet diameter. The data indicate that the two modes of vortex pairing are independent and excitation at one of the modes is sufficient to induce vortex pairing in the near field irrespective of whether the excitation ccorresponds to the other mode or not.
|Pages||11. 23-11. 31|
|State||Published - 1977|
|Event||Symp on Turbul Shear Flows, Pap - University Park, PA, USA|
Duration: Apr 18 1977 → Apr 20 1977
|Conference||Symp on Turbul Shear Flows, Pap|
|City||University Park, PA, USA|
|Period||04/18/77 → 04/20/77|