화학공학소재연구정보센터
Journal of Non-Newtonian Fluid Mechanics, Vol.53, 215-225, 1994
THE STRUCTURE OF TURBULENCE IN A DILUTE POLYMER-SOLUTION
The structure of turbulence is studied and quantified in terms of the higher order moments of the distribution of the velocity differences in the system. These moments are experimentally accessible with the technique of photon correlation spectroscopy. We have developed a new analysis scheme where the distribution of the velocity differences is calculated directly from the higher order spectral moments of the measured correlation functions. We studied, with this method, the effect of a drag reducing polymer on the structure of a turbulent flow. We observe that the polymer causes a large suppression of small velocity fluctuations accompanied by a large reduction of the turbulent volume fraction. The stretching of the linear, flexible polymer seems to cause a stabilization of the highly fluctuating turbulent core.