Ph.D. Thesis Defense

By

Eric S. Hendricks

(Advisor: Prof. Dimitri N. Mavris)

9:00 AM, Friday, November 4, 2016

Weber Space Science and Technology Building (SST-II)

Collaborative Visualization Environment (CoVE)

A Multi-Level Multi-Design Point Approach for Gas Turbine Cycle and Turbine Conceptual Design

ABSTRACT:

In order to address key challenges facing the aviation industry, NASA’s Advanced Air Vehicle Program researches new aircraft technologies and concepts.  Developing these new technologies and concepts is becoming increasingly difficult as the subsystems comprising these aircraft are highly coupled, often resulting in critical subsystem requirements and constraints throughout the flight envelope which drive the design.  This challenging design environment is particularly relevant in the development of propulsion system technologies for emerging aircraft concepts such as a large civil tiltrotor.  This work developed two complementary design methodologies to support the design of turbines and their associated engines for these new vehicle concepts. 

The first methodology developed focuses on facilitating the design of turbine components when requirements and constraints have been identified at a number of operating conditions.  To facilitate development of these designs, the method incorporates multiple design points into the on-design analysis phase to ensure that designs generated simultaneously satisfy all performance requirements and design constraints.  Development of this turbine multi-design point (MDP) method focused on determining the appropriate design parameterization for the turbine as well as formulation of design rules to couple the design points to assure the requirements and constraints are satisfied.

The second design methodology developed in this thesis aims to facilitate the design of the coupled turbine and engine system when requirements and constraints are present at multiple operating conditions for both systems.  Development of this method combined elements from the turbine MDP method and a similar cycle MDP using a new integration approach that directly couples the design points across the analysis levels. This multi-level, multi-design point (MLMDP) approach therefore simultaneously generates engine cycle and turbine designs that are consistent with each other while also satisfying all requirements and constraints at each analysis level.

Evaluation of these two design methods was completed by applying the methods to three selected design problems.  These problems included the design of two different power turbines and their associated turboshaft engines for a notional tiltrotor aircraft as well as the low pressure turbine for the E3 engine.  Experiments completed with these models validated critical components of the methodologies and assessed differences in the engine and turbine designs relative to those produced by traditional design practices.

Committee Members:

Dr. Mavris, Dr. Jagoda, Dr. Schrage, Dr. Tai, Dr. Welch (NASA Glenn Research Center)