Pressure measurement on an uneven and ablating surface

The feasibility of static pressure measurement through ablative materials exposed to an extreme hot-flow environment was investigated in an electric-arc tunnel facility. Pressure measurements were taken through carbon-phenolic and Teflon sample materials and compared with a reference measurement through a nonablating wall, simultaneously subjected to the same test conditions. The average deviations from the reference values were from 2% to 15%, and the maximum deviations ranged up to 40%. The pressure measurements through ablating Teflon tend to suffer from higher errors. The results indicate that static pressure measurement through an ablating material is possible but is limited to applications where accuracy is not mandatory