On the directional response of hot-wire probes

摘要

In the present study, a velocity/yaw-angle calibration was performed for single, slanted and x-type of hot-wire probes as well as wide range of velocities. From the large number of methods proposed in the literature for accounting for the directional response of the hot wire, four different methods have been applied to the experimental data. Limitations and errors using the various methods are systematically examined. It is demonstrated that the yaw parameters in the four yaw-angle methods vary with the yaw angle and flow velocity, and therefore a constant value is not suitable with a varying velocity flow. Moreover, the present study demonstrates that the classical cosine-cooling approach i8s as good as other methods for yaw angles <=70 deg and high velocieties.