Ph.D. Thesis Proposal

Egemen Aydin

(Faculty Advisor: Professor Dimitri Mavris) 

"Design Methodology for More Electric Engine Architectures with Dynamic Load Management and Life Cycle Performance Sustainment"

Wednesday, June 3

2:00 - 3:00 p.m.

Weber, CoVE

Abstract: 

The transition toward More Electric Aircraft (MEA) is driving a fundamental shift in propulsion design, as electrical loads from avionics, environmental control systems, and passenger services continue to rise. Yet despite this growing demand, engine power management remains fundamentally static: fixed extraction ratios and rigid spool architectures that cannot adapt to dynamic flight conditions or evolving engine health. Furthermore, as engines age, asymmetric spool degradation progressively erodes performance and operability, yet existing architectures offer no active mechanism to compensate. Traditional architectures based on fixed pneumatic, hydraulic, and electrical subsystems face growing limitations in weight, complexity, and fuel efficiency.

The More Electric Engine (MEE) addresses this by embedding shaft mounted motor/generators directly on both the high pressure (HP) and low pressure (LP) spools of the turbofan engine, enabling distributed electrical generation and dynamic load sharing between spools. Building on this foundation, Electric Power Transfer (EPT) further extends MEE capability by enabling bidirectional power exchange between the HP and LP spools through an electrical bus, reducing spool speed interdependency, improving transient performance, and reducing fuel consumption further. However, while MEE and EPT architectures have been conceptually established, the optimal dynamic control and scheduling of these systems across full mission profiles and engine life stages remains an open and unsolved problem.

Translating these architectural concepts into fully optimized, life-cycle aware systems, however, requires addressing three unresolved research challenges. First, no systematic methodology exists for determining how the optimal HP/LP power extraction ratio should be managed under dynamic aircraft electrical loads across full mission profiles. Second, the mission level benefits of MEE, including reductions in specific fuel consumption, improvements in compressor stall margin, and the trade-offs of added system mass and complexity, remain unquantified across diverse operational profiles. Third, the role of MEE in actively sustaining engine performance under asymmetric spool component degradation remains poorly understood, leaving open questions about life-cycle efficiency and operability.

This doctoral research addresses these gaps through advanced modeling and simulation of MEE architectures. The study proceeds in three phases: (i) systematic optimization of dynamic HP/LP power extraction strategies across mission phases, (ii) integrated assessment of EPT enabled architectures to quantify aircraft and engine mission level efficiency gains and operability improvements, and (iii) development of degradation-aware MEE control strategies to actively sustain performance and fuel efficiency across the engine life-cycle.

The expected outcome is MEDUSA (More Electric Dynamic Unified Sustainment Architecture), a unified design and evaluation methodology that enables optimization of HP/LP power extraction, EPT scheduling, and degradation-aware MEE control dynamically across mission profiles and engine life stages, providing the first quantitative basis for integrated More Electric Engine design and life-cycle performance sustainment.

Committee:
Dr. Dimitri Mavris (advisor), School of Aerospace Engineering
Prof. Daniel Schrage , School of Aerospace Engineering
Prof. Jechiel Jagoda , School of Aerospace Engineering
Dr. Jonathan C. Gladin , School of Aerospace Engineering
Dr. Metin Ozcan , PBS Aerospace