True ambient pressure sensitive (TAPS) paint will be immediately useful in wind-tunnel studies of hypersonic flow, where working fluids other than oxygen are often used to achieve Reynolds numbers characteristic of air flow at higher speeds, particularly in the study of real gas aerodynamic effects, including the world's largest pressurized cryogenic wind tunnel, the National Transonic Facility (NTF), the 0.3-Meter Transonic Cryogenic Tunnel and the Transonic Dynamics Tunnel (TDT). Advanced pressure sensitive coatings will be adopted rapidly by other aerodynamic test facilities where oxygen-independent pressure mapping is needed; for example, in the study of combustion-related phenomena (where the partial pressure of oxygen clearly does not depend exclusively on the local ambient pressure). Once the advantages of oxygen-free pressure mapping are demonstrated in these applications, TAPS-based PSPs will rapidly displace the conventional oxygen-sensitive paints in lower speed wind tunnels as well.
One very obvious advantage of TAPS PSPs is that they can be used in "water tunnels" for testing hydrodynamic structures. Thus, ship designers (including both the U.S. Navy and commercial naval architects) will be able to use the whole-surface image-based pressure mapping techniques now available to aerospace engineers. A large class of industrial and commercial structures that emit oxygen-reactive species – from tailpipes to smokestacks – that has hitherto been unaddressable by PSPs can be studied with TAPS paints. Pressure mapping of other non-aerodynamic structures (e.g., automobiles, trains, buildings) can be accomplished with conventional PSPs, but the increased shelf-life and stability of TAPS paints will make them attractive for these applications as well. Finally, the true-pressure-sensitive pigments developed in this project will also be useful in a host of spinoff applications, from "point sensors" (e.g., on the tips of optical fibers) to optical pressure switches.
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