Prediction of drag forces on a liquid jet in subsonic crossflow injector

Liquid jet in crossflow (JICF) injectors are a popular method of producing a spray of liquid droplets and therefore the liquid JICF atomisation process has been widely studied, with models developed for the jet trajectory and spread. To further develop these models, it is desirable to know the aerodynamic forces exerted on the liquid jet. In this paper, we present two simulations of a liquid jet injected into a subsonic crossflow at two different momentum flux ratios. An OpenFOAM Coupled Level Set & Volume of Fluid solver with Adaptive Meshing is used for the simulations. Methods for calculating the instantaneous pressure and viscous forces on the surface of the liquid column are presented, which are used to calculate forces in the streamwise direction. It is shown that the drag force on the liquid column is dominated by the pressure drag, which is at least three orders of magnitude greater than the skin friction drag. Discussion is given regarding the normalisation of the forces into coefficients, particularly the determination of the appropriate area. This understanding of how the forces on the liquid jet vary can help the development of new correlations for the modelling of liquid jet in crossflow atomisation.<p></p>