Assessment of Models for Liquid Jet Breakup

For many gas turbine architectures a failure modes and effects analysis identifies a potential mode in which failure of an oil transfer pipe could result in oil leakage into the secondary air system. Such an event would result in a complex two-phase interacting flow. The atomisation and transport of the oil within the air system is of interest, but is difficult to predict. Available data for the droplet size resulting from jet breakup in crossflow are limited. A dimensional analysis shows jet breakup in a crossflow to involve many factors. The atomisation process has been shown experimentally to include many physical processes and is still not completely understood. Currently, the most practical method of modelling these breakup processes in sprays is by using a CFD package with a set of sub-models within an Euler-Lagrangian (discrete-droplet) approach. The strengths and weaknesses of each of these sub-models cannot reasonably be tested when used in combination with other approximations to model a spray in crossflow. The purpose of this study was to assess various submodels for liquid breakup with a series of simple test cases.