Abstract
Gas turbine engines operating in harsh environments, such as deserts or volcanic areas, are prone to particulate ingestion, which degrades components like the compressor, combustor, and turbine, leading to increased maintenance, aircraft grounding, and potential failure. Engine Air Particle Separators (EAPS), including Inertial Particle Separators (IPS), are used to mitigate this issue. While IPS devices exhibit the lowest pressure losses (especially at high speeds), they are generally less efficient at separating particles than other EAPS technologies. This study investigates the fluid and particle dynamics of an axisymmetric sector IPS (a configuration rarely studied experimentally) using both computational and experimental methods. Particularly, Chapter 2 examines the flow field behavior through oil-streak experiments, characterizes six different flow splits, quantifies corner vortices, and presents surface flow visualizations and particle separation efficiency results for an axisymmetric-sector IPS flow path. Additionally, it assesses the influence of the Particle Delivery System (PDS) location on this flow path across various radial and vertical positions using two types of test dust (A4 Coarse and C-spec). Chapter 3 provides particle separation efficiency measurements for a performance-optimized axisymmetric IPS flow path under a comprehensive set of test conditions, including three test dusts of different sizes and three flow conditions (different scavenge flow splits). Chapter 4 employs Particle Image Velocimetry (PIV) to capture airflow velocity data upstream of the splitter that separates into the core and scavenge streams, presenting measurements of mean and fluctuating velocity in this critical region and identifying three instantaneous flow patterns based on scavenge leg blockage, which can impact particle separation. Finally, Chapter 5 focuses on the development of Large Eddy Simulations (LES) for an axisymmetric-sector IPS device, incorporating Lagrangian particle tracking with advanced drag and bounce models. The findings of this research offer valuable insights into particle separation in axisymmetric configurations and contribute to the development of more efficient IPS systems for gas turbine engines.
