High-Temperature Thermocouple and Heat Flux Gauge Using a Unique Thin Film-Hardware Hot Junction

Abstract

A special thin film-hardware material thermocouple (TC) and heat flux gauge concept for a reasonably high-temperature and high heat flux, flat-plate heat transfer experiment was fabricated and tested to gauge temperatures of 911 K. This unique concept was developed for minimal disturbance of boundary layer temperature and flow over the plates and minimal disturbance of heat flux through the plates. Comparison of special heat flux gauge Stanton number output at steady-state conditions with benchmark literature data was good and agreement was within a calculated uncertainty of the measurement system. Also, good agreement of special TC and standard TC outputs was obtained and the results are encouraging. Oxidation of thin film thermoelements was a primary failure mode after about 5 hr of operation.