抄録
We investigated a turbulent diffusion process of ethylene in a wake flow formed behind a circular cylinder installed in a grid turbulence using a simultaneous measurement system with a fast-response flame ionization detector (FFID) and a hot wire anemometer. Due to the existence of Karman vortex street, the mean and rms concentration distributions in the lateral direction have two peaks. The correlation coefficient between the streamwise velocity and concentration fluctuations indicates positive and negative values in the center and edge of the plume, respectively. Moreover, both of velocity and concentration spectra show the distinct peak at the dominant frequency caused by the vortex shedding.
