Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.
Drop formation at orifices and capillaries is applied in
different industrial applications. The transition from dripping to
the laminar jetting regimes must be known. In the non-viscous
case the transition point is characterized by a transitional Weber
number We = 2. For the viscous case particularly considered
here, another characteristic number is maybe more suitable.
Experiments are performed with viscous liquids for both phases
with equal density to obtain the characteristic parameter for the
transition. Droplet diameter, break up length and distance of
droplets which refers to the break up wavelength in the jetting
regime are analysed. In the laminar jetting regime different
kinds of drop formation could be observed and the influence of
the volumetric flow rate ratio to the jet diameter and relaxation
length is reported as well.