Wall Turbulence

摘要建议编号：CTS-9806265首席研究员：汉拉蒂这是一项继续研究固体边界上流动产生的湍流的拨款。目标是确定湍流是如何产生的，如何控制和改变湍流，如何预测雷诺应力。这项研究的一个重要特点是使用了直接数值模拟(DNS)、脉冲图像测速仪(PIV)、双分量激光多普勒测速仪(LDV)以及专门为湍流光学研究而建造的设备。主要目的是开发一个壁面湍流的概念框架，可以用来分析复杂的流动并确定如何修改湍流。所采取的方法是考虑产生应力的涡旋的结构和动力学。我们将研究(1)“简单”的壁面湍流，如在通道中充分发展的流动，(2)在静止或移动的波状边界上的流动，(3)减阻聚合物或表面活性剂溶液的流动，(4)在结构边界上的流动，(5)具有大幅度强迫振荡的流动。1 1

Abstract Proposal Number: CTS-9806265 Principal Investigator: Hanratty This is a grant to continue research on turbulence generated by flow over a solid boundary. The goals are the determination of how turbulence is produced, of how to control and change turbulence, of how to predict Reynolds stresses. An important feature of the research is that it uses direct numerical simulations (DNS), pulsed-image velocimetry (PIV), two-component laser-Doppler velocimetry (LDV), and a specially constructed facility for optical studies of turbulence. The chief thrust is to develop a conceptual framework for wall turbulence which can be used to analyze complex flows and to determine how turbulence can be modified. The approach taken is to consider the structure and dynamics of stress producing eddies. Studies will be made of (1) "simple" wall turbulence, such as fully developed flow in a channel, (2) flow over a stationary or moving wavy boundary, (3) flow of solutions of drag-reducing polymers or surfactants, (4) flows over structured boundaries, (5) flows with large amplitude imposed oscillations. 1 1