Experiments are conducted with water to determine the influence of the length to diameter ratio (L/d0) of the sharp-edged entry orifice and its exit geometry on the atomization. Both swirled and non-swirled water jets are investigated. The Sauter mean diameter of the droplets
is shown to be smaller at lower values of L/d0 of the orifice for the swirled and non-swirled jet. The increased azimuthal vorticity for non-swirled jet and the higher whirl momentum in the case of the swirled jet at the smaller L/d0 values are seen to be responsible for reduced droplet sizes. The range of variation of the sizes of the droplets is however larger at the small L/d0 values. The influence of flow and geometrical variables on atomization are discussed.