Development of a Distributed Approach to System Level Uncertainty Quantification

Project Category: 
Interdependencies and policy assessment
Project Number: 
48

As part of its tool development effort, the FAA Office of Energy and the Environment leads research analyses of policy outcomes to uncertainties in input parameters and assumptions of different tools. Project 48 created a new aircraft conceptual design capability in the FAA tools suite, through Transport Aircraft System OPTimization (TASOpt), and developed an approach to perform a system-level quantification of uncertainty. This system-level assessment quantifies how input uncertainties propagate through a system comprising multiple modeling components. Specifically, we quantified how uncertainties at the aircraft design level propagate through the Environmental Tool Suite and contribute to uncertainty in overall policy outcomes. We also conducted sensitivity analyses — identifying which input factors and assumptions contribute most to uncertainty in tool outputs.

To expand the aircraft conceptual design capability of the FAA Environmental Tool Suite, we established a process and codes for coupling TASOpt with Aviation Environment Design Tool (AEDT) Version 2a for fuel burn calculations. This coupling enables fleet-wide assessment of advanced technology aircraft configurations with respect to fuel burn changes and the associated environmental impacts. We expanded TASOpt’s capabilities through development of an elastic beam model that includes bending and torsion, a vortex-lattice model for aerodynamics, and an improved engine module.

Our system-level uncertainty quantification work developed a new distributed approach that permits the analysis to be performed locally on individual models, followed by a synthesis step to resolve couplings among models. In this way, we avoid the need to tightly integrate the various modeling components. The mathematical approach draws on concepts and algorithms from multidisciplinary analysis and optimization, density estimation, and sequential Monte Carlo methods. We implemented this new approach on a toolset consisting of TASOpt and AEDT Version 2a.

Project outcomes

TASOpt extensions that expand the Tool Suite capabilities in evaluating technology scenarios and assessing the impact of future aircraft designs. New methodology for a distributed approach to system-level quantification of uncertainty. Uncertainty analysis and sensitivity analysis of the coupled system comprising TASOPT and AEDT Version 2a.

Participating university

Massachusetts Institute of Technology

Lead investigator

Karen Willcox, professor, Aeronautics and Astronautics, Massachusetts Institute of Technology kwillcox@mit.edu

FAA program manager

 James Skalecky james.skalecky@faa.gov

Downloads

TASOPT Engine Model Development. Giulia Pantalone, Elena de la Rosa Blanco, Karen E. Willcox. September 2016. PARTNER Report No. PARTNER-COE-2016-004 Download pdf

Uncertainty Quantification of Aviation Fuel Burn Performance. Sergio Amaral, Elena de la Rosa Blanco, Douglas Allaire, Karen E. Willcox. September 2016. PARTNER-COE-2016-003 Download pdf