Geometric sensitivity of the NSTAP

Abstract

The nanoscale thermal anemometry probe (NSTAP) has been widely used to measure turbulence levels in high Reynolds number flows. Here, we report that the probe measurements are geometrically sensitive to its particular orientation in the flow under certain conditions. The geometric sensitivity appears as an amplification of the turbulence signal but has no effect on the mean. Data are taken using an NSTAP in multiple configurations and compared to data from previous studies and a conventional hot-wire. Results suggest that geometric sensitivity is caused by a difference between the mean and dynamic calibrations of the NSTAP.