Yuhui LIN, James J. WALLINGTON, Thien BUI, Toby VAN DEN HERIK, Christopher M. JAMES, Eric Won Keun CHANG, Tobias A. HERMANN
DOI Number: XXX-YYY-ZZZ
Conference number: HiSST2024-00355
The expansion tube is a unique hypersonic impulse facility capable of producing both high-enthalpy and high total pressure conditions simultaneously through the unsteady expansion of a non-stagnated test flow. When coupled with high-performance free-piston or detonation drivers, expansion tubes allow for the simulation of such conditions as scaled Earth re-entry, scaled entry into the atmospheres of other planets in the solar system, and high-speed flight through the Earth’s atmosphere. This paper focuses on the latter case and considers the capabilities of expansion tubes for re-creating the conditions experienced at various parts of the re-entry trajectory of a boost-glide vehicle. Boost-glide vehicles are a type of hypersonic vehicle which is boosted into space by a rocket and then `glides’ through the Earth’s atmosphere to a target, often re-entering at very high-speeds for flight in the atmosphere of up to Mach 22 (greater than 6 km/s). In a military sense, they are very important strategically and are currently being developed by several nations around the world. The expansion tube’s unique ability to simulate high-enthalpy and high total pressure flight makes it particularly well suited to the study of these conditions. This paper will present expansion tube performance envelopes compared to planned boost-glide trajectories and specific facility considerations required to generate these conditions. It will then provide sample experimental data and facility simulations to help quantify the sample conditions.