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Advanced computational models of hypersonic air-breathing combustion processes are being developed to better understand and predict the complex flows within a dual-mode scramjet combustor. However, the accuracy of these models can only be quantified through comparison to experimental databases. Moreover, the quality of computational results is dependent on accurate and detailed knowledge of the combustor inflow and boundary conditions. Toward these ends, this paper describes results from a collaboration of experimental and computational investigators. Detailed computational fluid dynamics and finite element analyses were performed throughout the design and implementation of experiments involving a direct-connect scramjet combustor operating at steady state during long duration testing. The test section hardware was designed to provide substantial access for optical laser diagnostics. Measurement locations included the inflow plane and several locations downstream of fuel injection. A suite of advanced in-stream diagnostics were applied, many of which are described in companion papers. Significant results in this paper include measured static wall pressures and temperatures, stereoscopic particle image velocimetry, and focused schlieren imaging. Validated thermal finite element calculations in the scramjet hardware and temperature maps of the flow path boundaries are also presented. Comparison of experimental results with computational fluid dynamics predictions are discussed in a separate paper. Nomenclature H = fuel injector normal ramp height h = convective heat transfer coefficient k = thermal conductivity P ref = measured static pressure immediately downstream of facility nozzle P o = flow stagnation pressure _ q = rate of heat transfer T o = flow stagnation temperature T r = recovery or adiabatic wall temperature T w = wall surface temperature x = axial coordinate γ = specific heat ratio φ = fuel equivalence ratio

Advanced computational models of hypersonic air-breathing combustion processes are being developed to better understand and predict the complex flows within a dual-mode scramjet combustor. However, the accuracy of these models can only be quantified through comparison to experimental databases. Moreover, the quality of computational results is dependent on accurate and detailed knowledge of the combustor inflow and boundary conditions. Toward those ends, this paper describes the initial results of a unique, close collaboration of experimental and computational approaches. Detailed computational fluid dynamics (CFD) and finite element thermal-structural analyses (FEA) have been performed throughout the design and implementation of a direct-connect scramjet combustor operating at steady state during long duration testing on the order of an hour or more. The test-section hardware has been designed to provide numerous access points for optical laser diagnostic measurements. Measurement locations include the inflow plane to the scramjet combustor as well as several locations downstream of the fuel injector. In addition, static wall pressures and temperatures are measured at numerous points along the fuel injector side of the scramjet flowpath. Initial CFD calculations were used to generate detailed thermal boundary conditions that were then applied to a non-linear, thermalstructural finite element model of the test-section. The calculated temperatures and thermal deformations are evaluated and validated against experimental measurements. Significant results described in this paper include experimentally measured static wall pressure and temperature data, Stereoscopic Particle Image Velocimetry (SPIV) and focused schlieren imaging. Validated finite element calculations of temperature in the test-section hardware, and temperature maps of the flowpath boundaries are also presented. CFD results are discussed in a separate paper.

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