In this research, new methods of mono-size droplet generation are studied. Unlike conventional spray processing techniques, which involve a distribution of droplets, a mono-size droplet spray provide a much simpler method of studying the fundamental mechanisms that govern spray processes since many parameters are uncoupled. Mechanisms that govern uniform droplet generation are investigated through comparisons of experimental droplet streams. Streams with droplet diameters in the size range of 50µm to 300µm are generated by capillary stream break-up with externally applied fixed frequency disturbances. Such disturbances are necessary to initiate uniform droplet generation with controlled droplet spacings.
Technical issues under investigation in this project include droplet stability and control, mass transport, and conductive heat transfer with phase change. Mathematical modeling includes the heat transfer, momentum transfer and solidification of a single droplet undergoing nonequilibrium phase change, coupled with the dynamics of spreading during impingement.