Abstract
It is well known that a pair of vortices is formed in the shear layer of unsteady jets. In this experiment, the vortex behaviour due to the difference of the nozzle shape (the difference of the length of the parallel section of the nozzle) has been investigated using the electroytic precipitation method and the hydrogen bubble method. It is found that the vortex moves faster when the parallel section of the nozzle is long than when it is short.
