Final work : Modeling of a fan blade-off event for electric fan thruster

Abstract

This MSc Thesis provides a comprehensive exploration of the electric fan thruster that is being developed under the EleFanT project, a collaborative effort between GKN Aerospace and KTH - Royal Institute of Technology. This project's primary objective is the development and analysis of a preliminary numerical model for the Hard-wall Containment design of the fan case, with a specific focus on addressing the challenges posed by Fan Blade-Off (FBO) events in aviation engines.

The thesis commences by detailing the key characteristics of the developed numerical model and the analytical methodologies employed to ensure its accuracy and reliability. General simulation conditions are established to serve as a baseline reference point. The study proceeds to examine the sensitivity of results to blade meshing within the elastic region, aiming to determine the optimal meshing configuration for the blade component. Subsequently, a similar sensitivity analysis is conducted at the system level, encompassing the entire Hard-wall Containment model. The outcomes of these analyses inform the final configuration selection while also acknowledging potential limitations in the model's representation.

The analysis deepens the understanding of the dynamic behavior of FBO events, with a focus on quantifying energy transfers and forces generated during distinct impact phases. A primary emphasis is placed on comprehending forces transmitted to the engine structure. Insights are drawn from analysis of time-evolving force signals, revealing the significance of considering vibrational forces experienced by the fan case following blade detachment.

The research culminates in a series of significant findings. The study demonstrates the pivotal role of energy transfers in dissipating kinetic energy, particularly through friction and blade deformation. Furthermore, the containment capability of the fan case is evaluated, yielding promising results that suggest its potential effectiveness in containing detached blades.

The findings illuminate the intricate dynamics of FBO events, and the various difficulties in constructing a reliable and realistic numerical model to represent it. The study also underscores the need for future research to delve deeper into the model's complexities and explore avenues for improvement. Given the project's scope, various facets remain ripe for further investigation, including refining meshing techniques, experimental validation, and exploring advanced failure criteria. This investigation represents a fundamental stride in propelling the enhancement of safety and efficiency within the EleFanT project's engine development, thereby establishing a pathway for continuous advancements in this critical realm.