Digital Prototyping Methodology for Cyclonic Multiphase Flow Separation

Safety and reliability are fundamental requirements for gas turbine engines. Continuous health monitoring and diagnostics devices are prime enablers for the same, and gaining a lot of attention for advancements. Oil debris monitoring is one of the important elements of an engine condition monitoring system. The cyclone separator is the key component of the debris monitoring system which separates air, oil and solid particles. The separation efficiency of various phases determines the cyclone performance and is governed by highly turbulent swirling flow field. Further, the particle capture efficiency depends on successful capturing of the flow field. Cyclone performance enhancement requires a detailed understanding of turbulent swirling multiphase flow field with free and forced vortex interactions. This poses a significant challenge for physical prototyping and demands detailed computational models to resolve the anisotropic structure of a turbulent flow field with multiphase interaction. Detailed investigation of various computational models such as turbulence models, multiphase models, and drag models has been carried out to capture the complex flow physics. A structured computational approach helped to establish a CFD methodology having a close match with experimental findings for all the performance parameters of three phase separation. The methodology is validated with the experimental results with the variation between CFD and experiments observed to be less than 10% for all four performance parameters namely pressure drop, air separation efficiency, oil separation efficiency and particle capture efficiency.