화학공학소재연구정보센터
Atomization and Sprays, Vol.28, No.8, 751-762, 2018
FISHBONE PATTERN FORMATION DUE TO ASYMMETRIES IN COLLIDING LOW-VELOCITY JETS
Here, we experimentally investigated the effects of skewness and velocity difference of two Newtonian colliding jets on the formation of a special oscillating liquid sheet pattern with periodic fragmentation, called fishbone, for four liquid sheet regimes known as the triple chain, double chain, close rim, and open rim. We expressed the ranges of the skewness and the velocity difference, where the fishbone pattern was formed for every four regimes. The formation of this special pattern was attributed to the instability of the liquid rim in the past studies. We qualitatively studied the upward and downward directions of the rims branched from the liquid sheet. Besides, the size variations of the rim were investigated to explain the liquid sheet behavior in different conditions of the asymmetry. According to the physical considerations on the appearance of the liquid sheet and the location of the initial perturbations, it was determined that the formation mechanism of the fishbone pattern is different for each case. The rim-driven instability has a key role in the fishbone pattern formation in the case of misaligned collision, and the sheet-driven instability is a substantial factor in the case of jet velocity difference.