LASER-DOPPLER MEASUREMENTS OF TURBULENCE STRUCTURE IN A DRAG-REDUCING PIPE FLOW WITH POLYMER INJECTION

JOURNAL OF CHEMICAL ENGINEERING OF JAPAN

HIROMOTO USUI¹  YUJI SANO¹  MATSURU KODAMA¹ 

[1] Department of Chemical Engineering, Yamaguchi University

关键词: Drag Reduction;    Polymer Injection;    Turbulence;    Laser Doppler Velocimeter;    Polymer Additive;   

DOI  :  10.1252/jcej.21.134

来源: Maruzen Company Ltd

【 摘 要 】

References(17)Cited-By(4)Aqueous solutions of polyethylene oxide were injected into a pipe flow through a small tube at the center of a pipe. The turbulent characteristics in drag-reducing flow with polymer injection were measured by means of a Laser Doppler Velocimeter (LDV). The experimental results were compared with measurements both in a Newtonian fluid (water) flow and in a premixed flow with 300 ppm homogeneous polymer solution. The experimental results suggested that the polymer injection caused a thickening of the buffer layer, enlargement of macroscale turbulent eddy and suppression of fine turbulent eddy. A difference in turbulent characteristics between premixed and polymer injected systems was observed in the distributions of turbulent macroscale, skewness factor and flatness factor. The enlargement of macroscale was more significant in the turbulent core region in the case of polymer injection experiments. The measurements of skewness and flatness factors showed that the low-speed fluid element caused by the ejection process passed more clearly the measuring position near the outer boundary of the buffer layer in the case of polymer injection experiments.

【 授权许可】

Unknown