界面活性剤水溶液の円柱周りの流れ : 円柱抗力とフローパターンに及ぼす界面活性剤添加の影響(流体工学,流体機械)

概要

論文の詳細を見る
To clarify the effects of surfactant solutions on the drag coefficient of a circular cylinder, the flow past a circular cylinder was investigated at 10<Re<7×10^3 by measuring the drag and by visualizing the flow. Six cylinders with diameters between 2 and 20mm were tested. Surfactant solutions were aqueous solutions of oleyl-methyldihydroxethyl ammonium choride in the concentration range of 50 to 200ppm with sodium salicylate. It was clarified that the drag coefficient of the cylinder in surfactant solutions increases comparing that in tap water in the lower Reynolds number range. On the contrary, the drag coefficient decreases in higher Reynolds number range. The maximum drag reduction ratio was approximately 55% for 200ppm solution at Re=7×10^3. The flow visualization results showed that the drag of surfactant solutions increases because of the existence of the wide stagnant zone around the cylinder. In addition, the numerical simulation results by using the FENEP model showed that the increase of apparent shear viscosity is an important factor of the generation of the stagnation zone.
社団法人日本機械学会の論文
2005-10-25