Theoretical analysis of heat and mass transfer in swirl atomizers

In this study, theoretical analyses have been performed to investigate the effects of atomizer construction and controlled pressure difference of swirl atomizers. The analysis of fluid field in the swirl chamber is governed by mass/energy conservation rules; in the region outside the nozzle, the analysis of oscillation of liquid sheet is based on Squire's expression for the amplitude growth rate. With some physical assumptions of control volume, initial values and model correlation, analytical results make it possible to predict film thickness, velocity distribution, spray cone angle and droplet size directly. The distribution of velocity profile and boundary layer thickness in the swirl chamber have been established with the aid of MATLAB. Based on the results we obtained, we here propose the change of individual design parameter and its corresponding flow number to optimize the performance of swirl atomizers. © 2006 Springer-Verlag.