The Patch Integral Method (PIM), a New Heat Transfer Analysis Tool for Hypersonic Wind Tunnel Facilities at NASA Langley

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Virginia Tech


The NASA Langley Research Center hypersonic wind tunnels serve a vital role in the field of hypersonics in both helping validate CFD predictions and producing experimental results. These tunnels have been heavily utilized for decades by numerous planetary missions, such as MSL and Orion, commercial and academic partnerships, such as Sierra Space and the University of Maryland, and flight projects such as Artemis and LOFTID. The data acquisition method used in these tunnels is thermography, primarily phosphor and infrared. Image data are not collected during model injection, resulting in a data gap in the time-history of temperature. Historically, an approximate method has been used to obtain heating data with the data gap, but a new, higher-fidelity method has been developed that patches the data gap and performs integral heat transfer analysis on the temperature data, directly solving the heat equation and avoiding unnecessary assumptions. This method has been shown to model the surface heating much more accurately, agree with computational predictions better than the current method, and be an overall more robust method that collapses to a constant film coefficient value much more quickly. The culmination of these aspects results in a method that is a significant improvement over the approximate method and increases the fidelity of the heating results obtained from the NASA Langley Research Center hypersonic wind tunnels.



Hypersonics, Aerothermodynamics, CFD, Experimental Hypersonics