Abstract
Cost-benefit analysis (CBA) is often unreliable as a decision-making tool, even in contexts where detailed cost and performance data are abundant. This limitation is amplified in novel technologies, like rotating detonation engines, where experimental data is limited and uncertain. Such decisions influence the allocation of resources and the distribution of risk in society. My STS research addresses the limitations of CBA by critiquing its oversimplification and bias, and suggesting positional analysis as a more appropriate alternative. My technical research addresses the data-side of this problem by developing a modular and replicable RDE test facility designed to generate more consistent experimental data. Together, these projects highlight the need to both improve the quality and quantity of available data for emerging technologies and adopt decision-making frameworks that can effectively account for sociotechnical complexity.
A novel propulsion device, the rotating detonation engine (RDE), has garnered much interest due to its high efficiency and reduced hardware complexity compared to conventional rocket and air-breathing engines. RDE research is limited by the strong coupling between detonation dynamics, flow conditions, and geometry, making it challenging to isolate fundamental detonation behavior and understand how geometry influences it. To solve this problem, my team and I designed a cost-effective, modular, and easily-customizable test facility for RDE research. RDEs are inherently difficult to study because their underlying detonation dynamics are not yet fully understood. Our test facility addresses this by simplifying the engine to a quasi-2D representation, enabling researchers to investigate fundamental detonation behavior and the influence of geometry in a controlled setting. The design is modular and replicable, allowing other researchers to use our template and implement their own geometries and experimental parameters. While preliminary proof-of-concept results have yet to be collected, simulations have revealed that our design will operate well within the chosen safety factors.
Cost-benefit analysis is an unreliable decision-making process because it collapses complex sociotechnical systems into one-dimensional, often monetary costs and benefits, and favors the interests of the decision maker. To investigate this problem, I analyzed evidence from multiple case studies to support the claims of oversimplification and bias of the decision-maker. I then examined these cases through the Social Construction of Technology (SCOT) framework. I also examined existing critiques of CBA to support my findings, which culminated in the case for positional analysis (PA), an alternative decision-making tool that better accounts for the limitations of purely quantitative evaluation of complex sociotechnical systems, as a more capable alternative. In my research, I found that CBA is unreliable even in its most ideal contexts, consistently underestimating costs and overestimating benefits. Additionally, I found that CBA fails to adequately account for societal and environmental impacts, often misrepresenting these effects when they cannot be reliably reduced to quantitative figures.
My technical work has produced a complete design for a detonation test facility that enables researchers to generate consistent, high-quality data on a versatile experimental platform. This will allow future applications of CBA in RDE projects to be based on a larger dataset with reduced uncertainty, minimizing the risk of CBA’s failure in these contexts. Future designers and researchers may improve on the test facility design’s sealing methods, modularity, and diagnostics to further establish it as a standardized experimental template. My STS research has produced a critique of CBA and made the case for positional analysis. Future work could evaluate implementation and effectiveness of PA, and examine additional decision-making paradigms.
I would like to extend my gratitude to Dr. Caitlin Wylie for her guidance and support through my STS research, and Dr. Chloe Dedic, Dr. Chris Goyne, Sean Sawaya, Sebring Smith, and Kemal Gokturk for their contributions to my technical project.
Notes
School of Engineering and Applied Science
Bachelor of Science in Aerospace Engineering
Technical Advisor: Chloe Dedic
STS Advisor: Caitlin Wylie
Technical Team Members: Connor Green, Josiah Martin, Saif Rahman, Alvin Kim, Brandon Dawson, Irion Thompson, Albert Castellon-Prado, Tyler Verry, Derek Liu, Jonathan Wang, Ryan Malatesta, Frederic Ramirez-Melenciano, Spence Hartman, Tyler Fisher