Session: 05-07 Topics in Instrumentation (III)

Paper Number: 82873

82873 - Highly Time Resolved, Combined Temperature and Heat Flux Measurement Technique Based on ALTP Sensors 

The aim of this paper is the investigation of a newly developed combined temperature and heat-flux measurement technique for direct fast response measurement at the wall. Two separate signals, i.e. surface temperature and wall heat flux within one sensing element with direct fluid contact are measured and evaluated. The sensor itself is based on the ALTP (Atomic Layer Thermopile)-technique and consist of an especially designed operational amplifier system for parallel temperature measurement.

Evaluation of the performance is carried out by means of different calibration facilities for convective and for radiative heat transfer. The test setups are capable of delivering heat flux densities up to 10 W/cm² with low repetition errors in the range of ±3 % [1]. By measuring the temperature and the heat flux at the wall at the same time, a more robust determination of the often desired wall heat-transfer coefficient or dimensionless Nusselt number is achieved.  

In addition, the two signals allow signal verification: The calculation of a heat flux signal based on the temperature measurement in comparison to a heat flux signal based on the direct voltage signal of the ALTP technique. The comparisons show a good agreement for both heat flux signals within a small deviation for the radiative and the convective test case. The usage of robust and well-known heat flux measurement techniques consisting of a coaxial thermocouple and a differential layer device acting as reference sensors within the calibration process allows a deeper investigation of the sensors accuracy.

[1] Huber, K, & Rödiger, T. "Comparison of Radiation and Convection-Based Calibration of Fast-Response Heat Flux Sensors." Proceedings of the ASME Turbo Expo 2020.

Presenting Author: Konstantin Huber UAS Landshut

Presenting Author Biography: Konstantin Huber, born in 1995, has a master’s degree in mechanical engineering (M.Sc.) from Friedrich-Alexander University Erlangen-Nürnberg. In 2018, he started to work as a research associate at the University of Applied Sciences Landshut. He is currently working on the development of fast-response heat flux sensors, their calibration and application in the research team of Prof. Dr.-Ing. Tim Rödiger.

Authors:

Konstantin Huber UAS Landshut
Tim Rödiger UAS Landshut