The Mechanical Design of A Modular Direct Connect Test Article

Currently, experimental data for the design of cavity flameholders of dual-mode ramjets at combustor flameout is limited. As high-speed airbreathing flight becomes more prevalent, this narrow scope of data could result in performance benefits being left unrecognized. To explore the impact of cavity geometry on dual-mode ramjet combustor operability, the NASA Langley Research Center (LaRC) has contracted North Wind to design two test articles to support the Technical Challenge 3 (TC-3) research program. The plan is to conduct these tests in NASA LaRC’s Direct-Connect Supersonic Combustion Test Facility (DCSCTF). These two test articles, one photoscaled to be half the size of the other, are being designed with modular cavities, fuel injector blocks, and window stations to allow NASA to test combustor performance across a wide variety of geometries and conditions. Each test article also includes an actuated choke device to provide backpressure in cases when fuel is not injected into the core flow. To allow for operation at conditions equivalent to flight enthalpies from Mach 5 to Mach 7, three different copper types, C10100, C18150, and GRCop-42, were selected for most components. Yttria Stabilized Zirconia (7YSZ) is being used as a thermal barrier coating and additive manufacturing allows for the routing of complex fuel and coolant passages used to ensure survivability. Thermal-structural analysis was conducted using ANSYS to validate and optimize the mechanical design of the test articles. This paper summarizes the state of the design and analysis of the TC-3 test articles up to the Critical Design Review (CDR).