Competitive Assessment of Aerospace Systems using System Dynamics Jens Holger Pfaender

284 Pages·2006·10.81 MB·English

Competitive Assessment of Aerospace Systems
using System Dynamics
A Thesis
Presented to
The Academic Faculty
by
Jens Holger Pfaender
In Partial Fulfillment
of the Requirements for the Degree
Doctor of Philosophy
School of Aerospace Engineering
Georgia Institute of Technology
December 2006
Copyright (cid:13)c 2006 by Jens Holger Pfaender
Competitive Assessment of Aerospace Systems
using System Dynamics
Approved by:
Prof. Dimitri Mavris
Dr. Peter Hollingsworth
Committee Chair
School of Aerospace Engineering
School of Aerospace Engineering
Georgia Institute of Technology
Georgia Institute of Technology
Dr. Fayette Collier
Prof. Daniel Schrage
Langley Aeronautical Research Center
School of Aerospace Engineering
NASA
Georgia Institute of Technology
Dr. Jim McMichael
Aerospace, Transportation
and Advanced Systems Laboratory
Georgia Tech Research Institute
Date Approved: 17 November 2006
To mom and dad, for your love, patience, and support.
Nunc bibendum est!
iii
ACKNOWLEDGEMENTS
I would like to extend thanks to the many individuals who have helped me through
this endeavor. I especially want to thank Prof. Dimitri Mavris, my advisor, for giving
me years of support and encouragement and for introducing me to a new way about
thinking about aerospace engineering in general. Dr. Daniel Schrage who brought
his considerable experience in aerospace systems design to my reading committee
and I feel privileged to have had the opportunity to get a different perspective on
things from him. I further want to thank Dr. Jim McMichael for his perspective and
curiosity in the field of advanced design methods and putting up with my brief set of
lectures in Advanced Design Methods III. Dr. Peter Hollingsworth provided me with
much needed input on details about aircraft and engine calibration. He also provided
me with much needed comments about the method in general. Last but not least, I
would like to thank Dr. Fayette Collier for providing guidance on NASA Langley’s
Aerospace Systems Analysis perspective on important challenges for systems design
and analysis, which provided some of the basis of this thesis.
ASDL at Georgia Tech has provided me with a number of contacts, experiences,
and most importantly good friends. I would also like to thanks Dr. Michelle Kirby
for providing me insights into FLOPS’ quirks and peculiarities. Similarly, I also want
to thank Dr. Elena Garcia for providing me with insight into the inner workings
of ALCCA. In general, everybody that provided me with comments and corrections
in the last months also deserves a round of thanks. I also want to thank Simon
Briceno and Ismael Fernandez for their sharing of ideas and thoughts about each of
our specialty areas and what they mean. Finally, Carl Johnson provided me with
insights and tips into neural networks.
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I will not attempt to list everybody that I got to know at Georgia Tech and in
Atlanta, doing so would take up a lot of space. My time here has been enjoyable and
fun. I’m looking forward to spending more time with you.
My family and friends in Germany that have given their encouragement and love
all my life no matter where my endeavors took me. I could not have make it without
you understanding and support this long way away from home. Mom, Alice, Dad,
even if you are not with us anymore...thanks.
Thank you all — without you, I could accomplish nothing.
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TABLE OF CONTENTS
DEDICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
ACKNOWLEDGEMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . iv
LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . x
LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
LIST OF SYMBOLS OR ABBREVIATIONS . . . . . . . . . . . . . . xiv
SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvi
1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1.1 Technological Factors . . . . . . . . . . . . . . . . . . . . . . 3
1.1.2 Economical Factors . . . . . . . . . . . . . . . . . . . . . . . 6
1.1.3 Regulatory Factors . . . . . . . . . . . . . . . . . . . . . . . 9
1.1.4 Perceived Factors . . . . . . . . . . . . . . . . . . . . . . . . 12
1.1.5 Interconnectedness . . . . . . . . . . . . . . . . . . . . . . . . 14
2 BACKGROUND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.1 Modern System Design Methods . . . . . . . . . . . . . . . . . . . . 15
2.1.1 Integrated Product and Process Development . . . . . . . . . 15
2.1.2 Robust Design Simulation . . . . . . . . . . . . . . . . . . . 16
2.1.3 Virtual Stochastic Life-Cycle Design Environment . . . . . . 18
2.1.4 Design Space Exploration . . . . . . . . . . . . . . . . . . . . 18
2.1.5 Surrogate modeling . . . . . . . . . . . . . . . . . . . . . . . 21
2.1.6 Technology Identification Evaluation and Selection (TIES) . 26
2.1.7 The Unified Tradeoff Environment . . . . . . . . . . . . . . . 27
2.2 Aircraft Market . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
2.2.1 Market Features . . . . . . . . . . . . . . . . . . . . . . . . . 30
2.2.2 Market Models . . . . . . . . . . . . . . . . . . . . . . . . . . 30
vi
2.3 Complexity Science . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
2.4 Foundation of System Dynamics . . . . . . . . . . . . . . . . . . . . 37
2.4.1 Industrial Dynamics . . . . . . . . . . . . . . . . . . . . . . . 37
2.4.2 Application to Social Systems . . . . . . . . . . . . . . . . . 40
2.4.3 Mathematical Foundation of System Dynamics . . . . . . . . 44
2.4.4 Current State of the Art . . . . . . . . . . . . . . . . . . . . 48
2.4.5 Existing Aerospace Applications . . . . . . . . . . . . . . . . 56
3 RESEARCH QUESTIONS & HYPOTHESES . . . . . . . . . . . . 60
3.1 Research Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
3.2 Hypotheses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
3.3 Explanation of Hypotheses . . . . . . . . . . . . . . . . . . . . . . . 61
3.3.1 Hypothesis 1: Engineering Analysis Integration with System
Dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
3.3.2 Hypothesis 2: Computational Feasibility . . . . . . . . . . . . 62
3.3.3 Hypothesis 3: Model Calibration . . . . . . . . . . . . . . . . 63
3.3.4 Hypothesis 4: Solution Space . . . . . . . . . . . . . . . . . . 63
3.3.5 Hypothesis 5: Solution Space Exploration . . . . . . . . . . . 64
3.3.6 Hypothesis 6: Probability Corridors . . . . . . . . . . . . . . 64
3.3.7 Hypothesis 7: Rapid Changes in External Drivers . . . . . . 64
4 SOLUTION APPROACHES TO FORMULATING A MARKET
MODEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
4.1 The Airline Decision Making Process . . . . . . . . . . . . . . . . . 66
4.1.1 Is there a Method to the Chaos? . . . . . . . . . . . . . . . . 67
4.1.2 Factors Affecting Purchasing Decisions . . . . . . . . . . . . 68
4.1.3 Fundamental Program Characteristics . . . . . . . . . . . . . 69
4.1.4 Goals for a Model . . . . . . . . . . . . . . . . . . . . . . . . 72
4.2 Competition Model . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
4.2.1 Polya Process Models . . . . . . . . . . . . . . . . . . . . . . 72
4.2.2 Measures of Merit . . . . . . . . . . . . . . . . . . . . . . . . 80
vii
5 IMPLEMENTATION OF AN INTEGRATED MODEL. . . . . . 83
5.1 Feasibility of Integration . . . . . . . . . . . . . . . . . . . . . . . . 83
5.2 Feasibility of an Analytical Integration . . . . . . . . . . . . . . . . 83
5.2.1 General Comments on the Feasibility of an Analytical Inte-
gration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
5.2.2 Formulation of an Analytical Integration . . . . . . . . . . . 87
5.2.3 Implications . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
5.3 Feasibility of a Numerical Integration . . . . . . . . . . . . . . . . . 91
5.3.1 General Comments on the Feasibility of a Numerical Solution 91
5.3.2 Formulation of a Numerical Integration . . . . . . . . . . . . 93
5.3.3 Code Execution . . . . . . . . . . . . . . . . . . . . . . . . . 96
5.3.4 Surrogate Modeling . . . . . . . . . . . . . . . . . . . . . . . 97
5.4 Analysis Code Integration . . . . . . . . . . . . . . . . . . . . . . . . 98
5.4.1 Direct Integration . . . . . . . . . . . . . . . . . . . . . . . . 102
5.4.2 Indirect Integration . . . . . . . . . . . . . . . . . . . . . . . 103
5.5 Competition Space Exploration . . . . . . . . . . . . . . . . . . . . . 104
5.6 Probability Corridors . . . . . . . . . . . . . . . . . . . . . . . . . . 109
5.7 Process Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
6 VALIDATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
6.1 Demonstration of Design Integration . . . . . . . . . . . . . . . . . . 118
6.2 Visualisation of Model Output . . . . . . . . . . . . . . . . . . . . . 126
6.3 Example Application . . . . . . . . . . . . . . . . . . . . . . . . . . 128
6.3.1 Wide Body Aircraft Market . . . . . . . . . . . . . . . . . . . 128
6.3.2 Aircraft Definition . . . . . . . . . . . . . . . . . . . . . . . . 135
6.3.3 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
6.3.4 Creation of Surrogate Models . . . . . . . . . . . . . . . . . . 142
6.3.5 Market Model . . . . . . . . . . . . . . . . . . . . . . . . . . 147
6.3.6 Extended Unified Trade-off Environment . . . . . . . . . . . 153
viii
7 MARKET VIABILITY BASED DESIGN . . . . . . . . . . . . . . 169
7.1 Inverse Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169
7.2 Market Exploration . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
7.2.1 Market Definition . . . . . . . . . . . . . . . . . . . . . . . . 173
7.2.2 Viable Aircraft . . . . . . . . . . . . . . . . . . . . . . . . . . 185
7.2.3 Insights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
8 CONCLUSIONS AND RECOMMENDATIONS . . . . . . . . . . 187
8.1 Contributions to Aerospace Systems Design . . . . . . . . . . . . . . 187
8.2 Lessons and Potential Improvements . . . . . . . . . . . . . . . . . . 191
8.3 New Research Paths . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
APPENDIX A — AIRCRAFT BASELINES . . . . . . . . . . . . . . 195
APPENDIX B — SURROGATE MODEL FIT RESULTS . . . . . 212
APPENDIX C — SOURCE CODE . . . . . . . . . . . . . . . . . . . 220
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256
VITA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
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LIST OF TABLES
Table 1 List of Aircraft type classifications . . . . . . . . . . . . . . . . . . 33
Table 2 List of Total Market Values . . . . . . . . . . . . . . . . . . . . . . 131
Table 3 Aircraft Calibration Parameters . . . . . . . . . . . . . . . . . . . . 136
Table 4 List of Economic Calibration Variables . . . . . . . . . . . . . . . . 138
Table 5 Economic Calibration Variables for the 767-400ER . . . . . . . . . 139
Table 6 List of Surrogate Model Variables . . . . . . . . . . . . . . . . . . . 143
Table 7 List of Market Model Calibration Variables . . . . . . . . . . . . . 151
Table 8 List of Market Model Calibration Results . . . . . . . . . . . . . . 152
Table 9 Goodness of Market Model Fit . . . . . . . . . . . . . . . . . . . . 152
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