Hot Wire Anemometry (HWA) methodology has yet to fully realize its potential. As a consequence, nowadays, the use of HWA is unapplicable to flow conditions in the range of 0.4<M<1.2. This research aims to address this gap by extending the use of HWA to cover the compressible flow range typical in turbomachinery applications.
This research proposes a novel method to decouple and obtain the instantaneous characteristics of the flow, for an incompressible and supersonic field using HWA probe with at least 3 wires. The sensitivities of the velocity, Temperature and density, to the electrical voltage applied on the wire , are obtained from normalized characteristics of the flow ( , and ). Using a calibration process Reynolds-Nusselt curve is generated. This calibration can be conducted in a free jet facility without the need of a complex closed loop wind tunnel. Using a probe with slanted wires, a decouple of the flow angles can be obtained, by calibrating the ratio between the free stream Reynolds and the effective Reynolds on the wire to the flow angle.
5 Wire HWA was created to demonstrate the capabilities of the probe towards conducting an experiment on an engine. Optimization was used to set the best wire properties such as wire temperature and diameter to maximize the accuracy of the results.
A probe calibrated in this manner can therefore provide accurate instantaneous data of small fluctuations in the flow and can potentially lead to a breakthrough in the research and development of state-of-the-art turbomachinery applications.