Abstract
For my Capstone project, I designed an unpowered hypersonic projectile for low altitude flight. The design was submitted to a national competition hosted by the University Consortium for Applied Hypersonics (UCAH) and selected as a finalist for wind tunnel testing. My STS thesis examines the social construction of U.S. hypersonic weapons through four existing interpretations of the technology in policy literature. The existence of UCAH and its undergraduate competition are a part of this social construction process. UCAH was created by the Joint Hypersonics Transition Office (JHTO) of the U.S. Department of Defense for the purpose of workforce development. One source reviewed in my thesis for its interpretation of hypersonic weapons as a revolutionary technology explicitly references enhancing the JHTO as part of its overall recommendations on U.S. hypersonic weapons. The engineering work I performed for Capstone contributed to U.S. hypersonic missile design while my thesis examined the flexible social meanings of such technologies.
My Capstone team designed an unpowered hypersonic projectile for a national competition hosted by UCAH. The primary objectives of the competition were to maximize projectile range and maintain ease of manufacturing. Other design constraints were set by competition rules for projectile size, mass, stability, and maximum temperature. Computational fluid dynamics (CFD) analysis and surrogate modeling were critical for the design process given the inability to perform benchtop tests at hypersonic conditions at UVA. The Ansys Fluent commercial CFD solver was used to conduct parameter studies, build a surrogate model, and provide inputs for finite element and trajectory analyses. The design process was guided by the principle of optimizing the lift-to-drag ratio in order to maximize projectile range through a glide trajectory.
After submitting our design report in December, we were selected as competition finalists and are preparing to test our design at the CUBRC hypersonic wind tunnel facilities in Buffalo, New York this summer. Our final design is intended to be launched from a ballistic gun at Mach 8 with a launch angle of 23°. It will impact the ground 100km away at a speed of Mach 3.2 after a flight time of 64 seconds. At its maximum altitude of 9 kilometers, the design generates 6621 Newtons of lift, enough to sustain a 15g pull-up maneuver at its mass of 33.6 kilograms. A modified version of the projectile was designed to fit the needs of high-speed wind tunnel tests. This test article design will be used to gather force data across angles of attack and to visualize shock locations. Data from the wind tunnel tests will be used to validate the CFD from the design process and to update the surrogate model of the projectile’s aerodynamics.
Hypersonic missiles travel at speeds greater than five times the speed of sound and possess a higher degree of maneuverability than traditional ballistic and cruise missiles. While the United States has not currently established a plan of record for a scaled hypersonics program, adversary states Russia and China are both known to possess hypersonic military capabilities. At hypersonic speeds, missile aerodynamics are dominated by intense thermal effects that complicate design and contribute to the high costs associated with hypersonics research. Public doubt has been cast on the value of the U.S. pursuing hypersonic capabilities despite the adversary gap. The U.S. faces the technical challenges associated with design in the hypersonic regime and policy decisions about the future of its current hypersonic prototyping programs. My STS paper answers how the developing technology of U.S. hypersonic weapons is being socially constructed in this policy context. Using Pinch and Bijker’s Social Construction of Technology, four existing interpretations of the technology are identified and examined through a literature review: U.S. hypersonic weapons as an evolutionary technology, U.S. hypersonic weapons as a revolutionary technology, U.S. hypersonic weapons as globally stabilizing, and U.S. hypersonic weapons as globally destabilizing.
As the conflicting nature of these interpretations suggests, U.S. hypersonic weapons have not yet reached a stabilized, closed form. Existing forms of the technology represent ongoing attempts at rhetorical closure and closure by redefinition of the problem. The current flexibility of hypersonic weapons has implications for policy makers. The meaning of U.S. hypersonic weapons is not predetermined by the possible sets of technical specifications for these systems. Practically, Congress cannot choose to fund a globally stabilizing program built to be such by engineers. Future decisions by legislators, engineers, and other relevant social groups will continue to construct these social meanings for U.S. hypersonic weapons. This analysis also contributes to the Social Construction of Technology theory by applying Pinch and Bijker’s framework to a developing artifact.
Notes
School of Engineering and Applied Science
Bachelor of Science in Aerospace Engineering
Technical Advisor: Xinfeng Gao, Christopher Goyne
STS Advisor: Pedro Augusto Francisco
Technical Team Members: Michael Della Santina, Ava Frodsham, Lukas Hange, Kayla Kadlubek, Owen McGilberry, Joe McPhail, Arwen Nicolau, Michael Novak, Soren Poole, Channing Reynolds, Joshua Stoner, Victoria Sun, Eric Voight
