High-fidelity simultaneous measurements of velocity and temperature fluctuations using a dual-wire sensor within thermal boundary layers

Abstract

A customised dual-wire sensor, incorporating both a cold-wire and a hot-wire, has been developed to enable simultaneous measurement of temperature and velocity at the same wall-normal location within a thermal boundary layer. This study details the sensor’s design, its in-situ calibration technique, and addresses potential sensor drift, offering guidance for its effective utilisation. While the results obtained from this sensor confirm the similarity between the wall-normal profiles for mean temperature and velocity, profiles of the temperature variance present a less obvious plateau in the logarithmic region when compared to the streamwise velocity variance. The simultaneously acquired inst..