平行二線式熱線流速計による乱流境界層内変動速度計測の試み

抄録

A novel hot-wire technique consisting of two parallel hot-wires is proposed. The gap between the two parallel wires is filled with an adhesive, which can be expected to improve the sensitivity to the flow angle at high velocity regions. In the present study, measurement accuracy of the two component velocity fluctuations is appraised experimentally in a flat-plate turbulent boundary layer. As a result, it was verified that the present probe can reproduce not only the DNS database but also the measurements obtained by the standard I- and X-type hot-wire probes. In addition, the proposed probe can be brought closer to the wall than the X-type one. However, it is observed that the turbulent intensity measurements in the streamwise direction are slightly reduced, and the power spectrum of the streamwise velocity fluctuations is attenuated accordingly in a high-frequency range. Thus, fluid-dynamical and thermal effects of the adhesive need to be investigated in more detail in the future.