角柱を挿入したチャネル乱流の速度場と温度場の同時測定

抄録

Experiments have been conducted for turbulent channel flow obstructed with a square rod placed perpendicular to the flow. The streamwise distributions of the similarity parameter 2St/Cf were examined for four different space ratios between the square rod and the channel wall. The dissimilarity between momentum transfer and heat transfer was intensified in the case when the square rod was slightly detached from the channel wall. Simultaneous measurements of velocity and temperature were taken by making use of hot-wire and cold-wire probes in the case when the space ratio, y'=0.7. Wavelet analysis applied to the velocity and temperature signals was found effective for the extraction of periodically changing patterns of flow and thermal fields. Through the analysis, heat transfer enhancement was related to the intensification of cold and hot interactions toward the wall and away from the wall, respectively, which occurs depending on the existence of periodical change of flow structure.