Seventh International Symposium on Turbulence and Shear Flow Phenomena
DOI: 10.1615/TSFP7
EVIDENCE FOR THE PERSISTENCE OF HAIRPIN FOREST IN TURBULENT, ZERO-PRESSURE-GRADIENT FLAT-PLATE BOUNDARY LAYERS
pages 1-6
DOI: 10.1615/TSFP7.1610
ABSTRACT
We report well-resolved flow visualization results obtained from very-large-scale direct numerical simulation (VLS DNS) of a nominally zero-pressure-gradient, smooth, incompressible, flat-plate boundary layer (ZPGFPBL). The momentum-thickness Reynolds number develops continuously from 80 to approximately 2000. A unique aspect of the present VLS DNS study is its strong connection and remarkable consistency with the large body of classical ZPGFPBL experimental visualization work that began in the late 1950s, peaked in the early 1980s and still somewhat active until this day. Our VLS DNS results demonstrate, beyond reasonable doubt, a preponderance of hairpin vortices in ZPGFPBLs upto momentum-thickness Reynolds number 2000.