Thermal performance of a supersonic high temperature optical probe nacelle

This study presents a multi-step approach to design and evaluate the cooling architecture of an actively cooled probe nacelle suitable for high-temperature supersonic flows. First, a 1D heat transfer model was used to determine the coolant pressure required for thermal protection of the nacelle at supersonic conditions. It incorporates conductive-convective heat transfer, effusion cooling, leading-edge effects, and high-speed boundary layer effects. A parametric analysis identified a minimum coolant pressure of 2.4 bar to satisfy the temperature limits of the nacelle at the most severe conditions of M 1 = 6 , T 01 = 1700 K . 3D RANS simulations were utilized to assess the accuracy of the 1D model giving average deviations in adiabatic cooling effectiveness and heat transfer coefficient below 6% and 15% respectively. Finally, the cooling performance of the nacelle was assessed in a transonic open jet. Cooling effectiveness was measured with high-resolution infrared thermography, and heat flux was measured with high-frequency Atomic Layer Thermopiles (ALTP). Uncertainties in cooling effectiveness and heat transfer coefficient were evaluated through Taylor propagation and Monte Carlo simulations, respectively. Oil-flow visualization was conducted to compare the surface flow behavior in the effusion cooled face between simulations and experiments, while Schlieren was used to compare the bow shock location and shape. A comprehensive comparison is conducted involving analytical models, simulations and experiments that validate the proposed methodology. • First unified 1D 3D experimental methodology for supersonic cooled-probe design. • Actively cooled probe enables optical tests from transonic to Mach 6 and 1700 K. • IR, thermopile, schlieren, and oil tests link heat flux, cooling, and flow topology. • 1D and 3D models agree within 15% for HTC and 7% for cooling effectiveness.