Large Eddy Simulation with Lagrangian Particle Tracking of an Inertial Particle Separator

An inertial particle separator (IPS) is a device used to remove particulates from an airflow by exploiting the inertia of particles and geometric constraints to manipulate the incoming inflow of an engine. It is commonly employed in gas turbine engines to protect internal components from damage caused by ingested debris, dust, and sand. In this study, we investigate the unsteady flow behavior and particle separation efficiency of an IPS using Large Eddy Simulation (LES) and Improved Delayed Detached Eddy Simulation (IDDES). The LES approach captured complex flow structures in the scavenge channel, including rippling effects and vortical structures upstream of the splitter that were previously undetected. Particle separation efficiency was examined across a wide range of sizes, showing a sigmoidal trend: near-zero efficiency for particles smaller than 10 μm and over 95% separation for particles larger than 10 μm. Efficiency for very large particles (>100 μm) slightly decreased due to particle-wall interactions. The computational efforts demonstrated stable predictions of separation efficiency across time snapshots, with little sensitivity to mesh density or turbulence models. However, the model overestimated separation efficiency for smaller particles (6.5–13 μm) compared to experimental results, indicating areas for future refinement. Overall, the study underscores the accuracy of LES for IPS simulations while identifying potential improvements for smaller particle predictions.