This book presents research on Boundary Layer Ingestion (BLI). BLI is an aircraft-engine
integration technique that aims at integrating the aircraft and the propulsion system such that
the overall aircraft fuel consumption can be reduced. In this research theoretical analysis
suggests that the minimization of total power consumption should be used as a design criterion
for aircraft utilizing BLI rather than focusing on the minimization of drag. Numerical
simulations are performed and the simulation results are processed using the PBM to support
the theoretical analysis. Furthermore an experimental study is carried out with a focus on the
power conversion processes involved for a propulsor operating in the wake. Stereoscopic PIV is
employed in order to visualize the flow and understand the physics. The so-called Power-based
Method is used to quantify the power conversion mechanisms. The results prove that the dominant
mechanism responsible for the efficiency enhancement is due to the utilization of body wake
energy by the wake ingesting propeller. In short the importance of wake energy flow rate in
understanding the BLI phenomenon is highlighted. This book will be useful for researchers in
the field of aircraft propulsion aircraft aerodynamics and airframe propulsion integration.
