Simultaneous measurements of velocity and temperature fluctuations in thermal boundary layer in a drag-reducing surfactant solution flow

F. C. Li, D. Z. Wang, Y. Kawaguchi, K. Hishida

Research output: Contribution to journalArticle

49 Citations (Scopus)

Abstract

The mechanism of turbulent heat transfer in the thermal boundary layer developing in the channel flow of a drag-reducing surfactant solution was studied experimentally. A two-component laser Doppler velocimetry and a fine-wire thermocouple probe were used to measure the velocity and temperature fluctuations simultaneously. Two layers of thermal field were found: a high heat resistance layer with a high temperature gradient, and a layer with a small or even zero temperature gradient. The peak value of u +θ+ was larger for the flow with the drag-reducing additives than for the Newtonian flow, and the peak location was away from the wall. The profile of -v+θ- was depressed in a similar manner to the depression of the profile of -u++v+ in the flow of the surfactant solution, i.e., decorrelation between v and 6 compared with decorrelation between u and v. The depression of the Reynolds shear stress resulted in drag reduction; similarly, it was conjectured that the heat transfer reduction is due to the decrease in the turbulent heat flux in the wall-normal direction for a flow with drag-reducing surfactant additives.

Original languageEnglish
Pages (from-to)131-140
Number of pages10
JournalExperiments in Fluids
Volume36
Issue number1
DOIs
Publication statusPublished - 2004 Jan 1

ASJC Scopus subject areas

  • Computational Mechanics
  • Mechanics of Materials
  • Physics and Astronomy(all)
  • Fluid Flow and Transfer Processes

Fingerprint Dive into the research topics of 'Simultaneous measurements of velocity and temperature fluctuations in thermal boundary layer in a drag-reducing surfactant solution flow'. Together they form a unique fingerprint.

  • Cite this