Fast-response heat-flux sensor for measurement commonality in hypersonic wind tunnels

A fast-response heat-flux sensor, based on a modified Schmidt-Boelter gauge principle of operation, has been developed for commonality of heat transfe r measurement methodologies in Arnold Engineering Development Center hypers onic wind tunnels. This sensor retains the direct-reading and self-generati ng high-output capabilities of the traditional Schmidt-Boelter gauge, but a novel fabrication feature provides near first-order exponential time respo nse with time constants in the 10-15-ms range. This transducer can be used in blowdown wind tunnels as well as quasi-steady-state measurement applicat ions. Coupled with recent developments in data correction and time-response algorithms, the development of this direct-reading sensor has significantl y improved the accuracy and versatility of heat-flux measurements in hypers onic testing applications. Gauge design features, laboratory performance ch aracterization, generalized algorithm development, and hypersonic wind-tunn el data comparisons are presented.