Study of Flow Deformation around Wind-Vane Mounted Three-Dimensional Hot-Wire Probes

Open wind tunnel tests on several different sensor systems consisting of triaxial hot-wire probes mounted on wind vanes (DISA and Riso vanes) have shown that flow deformation around the hot-wire sensor introduces errors in the measured velocity components. Though changes in the horizontal components proved to be negligible, flow deformation resulted in an overestimation of the vertical component from 1.1 to 1.5, depending on the direction of the vertical component. Turbulence and mean value data were adjusted by use of a linear correction derived from the wind tunnel tests. Wind vane construction must strike a compromise between minor flow disturbance and sufficient probe support. The final version of the DISA vane resulted in an acceptable vertical correction of about 10%.