Acquisition of Laser Doppler Velocimetry System for Turbulence Research

摘要建议编号：CTS-0421561首席研究员：西雅图大学P.W.丰塔纳这笔赠款用于购买激光多普勒测速(LDV)系统，用于西雅图大学流体湍流实验室的湍流研究。该仪器的初步研究涉及湍流的剪切流抑制现象。这一现象尚不完全清楚，但据信这是火山喷发产生的空气悬浮颗粒无法进入或离开赤道喷流、南极涡旋中的臭氧空洞持续存在以及最佳聚变反应堆放电中所见的良好约束的原因。本实验将通过在悬浮表面活性剂层中诱导湍流剪切流动，并直接测量剪切对输运的影响，来控制和全面地研究剪切流动对湍流的抑制。对结果的分析将使实验数据与新兴理论首次进行系统的定量比较。LDV是这项研究的基本诊断，因为它将提供分析流动动力学所需的时间分辨数据。该仪器将极大地扩大在这些实验中取得的结果的范围和影响。LDV也是多才多艺的，随着研究的扩展，它将继续成为实验室的核心要素，超越这些最初的实验。这项研究是受聚变能源研究中当前问题的推动并与之直接相关的。对这种取之不尽的清洁能源的追求已成为国家和国际的新的优先事项。西雅图大学主要是一所本科院校，因此这个项目将为本科生提供参与科学前沿的机会。教学课程也将受益于这一最先进的LDV系统的存在，该实验室将促进招收高素质的理工科学生。该大学及其科学与工程学院招收了大量代表不足的群体和女性，因此这些群体尤其将从该项目承诺的研究机会和教学改进中受益。

ABSTRACTProposal No. CTS-0421561Principal Investigator: P. W. Fontana, Seattle UniversityThis grant is for acquisition of a laser Doppler velocimetry (LDV) system for use in turbulence research in the Fluid Turbulence Laboratory at Seattle University. The initial investigations in which this instrument will be used involve the phenomenon of sheared flow suppression of turbulence. This phenomenon is not yet fully understood, but is believed to be responsible for the restriction of airborne particulates from volcano eruptions from entering or leaving the equatorial jet, the persistence of the ozone hole in the South Polar vortex, and the good confinement seen in the best fusion reactor discharges. This experiment will be a study of sheared flow suppression of turbulence in a controlled and comprehensive way by inducing turbulent sheared flows in suspended surfactant layers and directly measuring the effects of the shear on transport. Analysis of the results will enable the first systematic quantitative comparison of experimental data with the emerging theory. The LDV is an essential diagnostic for this research because it will provide the time-resolved data needed to analyze the dynamics of the flow. The instrument will significantly broaden the scope and impact of the results to be achieved in these experiments. The LDV is also versatile, and will continue to be a central element of the laboratory as the research expands beyond these initial experiments. This research is motivated by and has direct bearing on current issues in fusion energy research. The pursuit of this limitless source of clean energy has become a renewed national and international priority. Seattle University is a primarily undergraduate institution, so this project will afford undergraduates an opportunity to participate at the frontiers of science. The teaching curriculum will also benefit from the presence of this state-of-the-art LDV system, and the laboratory will promote recruitment of highly-qualified students in the sciences and engineering. The university and its College of Science and Engineering have large enrollments of underrepresented groups and women, so these groups particularly will gain from the research opportunities and teaching enhancements promised by this project.