Abstract
As a part of study on the jet control, the flow direction control of the jet was tried. The main jet issues from a circular pipe and the sub one from a half pipe placed on the side wall. The experiment of the direction control was conducted, changing the velocity difference between the main jet and the sub one. The flow visualization was carried out by the smoke method. As a result, it is clarified that the main jet was leaned toward the sub one, under the influence of the entrainment of the wall sub jet. Moreover, it is found that the direction control of the main jet is easy in the case that the velocity difference between the main jet and the sub one is large.