The flow from a tank can be regarded as both steady and transient. In the steady case the fill level, and thus the width of the jet, remains constant (e.g. discharge under a weir).
When the tank is emptying during the discharge process, it is in what is referred to as the transient state.

Determination of pressure losses and contraction coefficient for different outlet contours.

Recording the trajectory of the water jet and discharge coefficients at different outlet velocities.