图书馆订阅: Guest
First Symposium on Turbulence and Shear Flow Phenomena
September, 12-15, 1999, Doubletree Resort, Santa Barbara, California, USA

DOI: 10.1615/TSFP1

MODIFICATION OF NEAR-WALL STRUCTURE IN A THREE-DIMENSIONAL TURBULENT BOUNDARY LAYER

pages 157-162
DOI: 10.1615/TSFP1.270
Get accessGet access

摘要

The near-wall physics and turbulence structure of a planar, shear-driven, three-dimensional turbulent boundary layer (3DTBL) are examined in a specialized facility with varying strengths of crossflow. The spanwise shear results in a modification of the near-wall turbulence structure. Analysis of flow visualization data reveals a reduction of mean streak length by as much as 50% with increasing spanwise shear, while streak spacing remains relatively constant. Power spectra of velocity confirm this shift towards higher temporal frequencies, corresponding to decreased streamwise length scales. Particle image velocimetry measurements indicate a significant modification of the inner region of the boundary layer with increasing spanwise shear. Streamwise velocity profiles exhibit an increasing velocity deficit with increased crossflow. Increased levels of the normal Reynolds stresses u2 and v2 and an increase in the − uv Reynolds shear stress are also observed. Notable modifications in the spanwise vorticity were also observed at higher shear rates.

Begell Digital Portal Begell 数字图书馆 电子图书 期刊 参考文献及会议录 研究收集 订购及政策 Begell House 联系我们 Language English 中文 Русский Português German French Spain