Abstract
The present contribution deals with numerical and experimental studies of the primary liquid breakup process using a high-speed rotary bell atomizer. The investigation focuses on the disintegration process of the paint liquid in the near-bell region. A hybrid multiphase model that links the Volume of Fluid (VOF) model and the Discrete Phase Model (DPM) is implemented in the CFD software ANSYS Fluent. In the simulation, the VOF model tracks the liquid-gas interface to describe the flow of the liquid film on the bell and the liquid disintegration at the bell edge. Under the given conditions, the developed hybrid model converts the liquid lumps resulting from the VOFsolver into point masses that can be further tracked using the DPM model. Moreover, droplet properties such as volume, equivalent diameter, velocity and position can be determined with the DPM statistics. The resulting quantitative simulation data, i.e. drop velocities and droplet size distributions, are compared with the experimental results applying Laser Doppler Anemometry (LDA) and laser diffraction instruments.