Application of PSP in low pressure regime

The PSP technique has the capability to be applied to high Knudsen number flows, such as low density gas flows, micro-flows, and so on. In this study, fundamental properties of PSPs such as sensitivity to pressure are examined especially in the range of pressure below 150 Pa (about 1 Torr), to select the most suitable PSP for the low pressure range. One of the PSP is Bath-Ru adsorbed directly on anodized aluminum, and the other PSPs are composed of porphyrin complexes bound by glassy polymer poly(TMSP). As an application of PSP to low density gas flows, we measure a pressure distribution on a surface of an aluminum plate interacting with a low density supersonic free jet. The clear two-dimensional pressure distribution was obtained by using PtTFPP/poly(TMSP), showing the feasibility of quantitative pressure measurement using the PSP.