Investigation of the interacting flow of non-symmetric jets in cross flow

Asymmetric jets in cross-flow provide interesting interacting flow fields which contain many vortices. These vortices vary significantly with variations of the jet and the cross flow and under certain specific conditions shedding vortices appear and disappear periodically. Four different cross section geometry jets were studied and compared with a circular cross section jet with the same jet port exit area. Various flow visualization techniques were used to aid in understanding of the highly three dimensional and complex flow field. Among many forms of secondary vortices produced four major vortices were identified in general. The most notable and interesting kind was the 'spin-off' vortices observed previously in the study of discrete jets blowing from a wing tip. These shedding vortices were formed under certain flow conditions and jet orientations. The shedding vortices were nearly parallel to the jet exit axis with periodicity depending on the jet to the free stream velocity ratio. A reconstruction of the asymmetric flow field based on observations and its evolution and relationship with established symmetric jet in cross flow were made. Unsteady jets created by pulsation of the jet flow at low pulsation frequencies behaved significantly differently than the steady jets.