Long and Medium-Term Research: Velocity and Concentration Measurements in the Turbulent Jet and the Jet in Counterflow

中长期研究：湍流射流和逆流射流的速度和浓度测量

• 批准号: 9202425
• 负责人: Minami Yoda
• 金额: $ 4万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-15 至 1995-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9202425&HistoricalAwards=false
• 关键词: Long; Medium; Term; Research; Velocity

Long and Medium-Term Research: Velocity and Concentration Measurements in the Turbulent Jet and the Jet in Counterflow This award is under the Long and Medium-Term Research at Foreign Centers of Excellence Program, which enables U.S. scientists and engineers to conduct three to twelve months of research abroad at research centers of proven excellence. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twelve-month postdoctoral research visit by Dr. Minami Yoda of Stanford to work with Dr. Heinrich Fiedler at the Technical University of Berlin. Their research project involves development of techniques for the simultaneous acquisition of two-dimensional concentration and velocity fields for application in turbulent water flows. This technique will initially be developed in a fundamental flow, the axisymmetric jet, to evaluate its accuracy and applicability. They will then use their technique to investigate the jet in counterflow, a new flow which is of interest because it displays transition from convective to absolute instability. In both cases their approach will involve marking the flows first with flueorescent dye to measure the two-dimensional (passive scalar) concentration field, then with neutrally buoyant particles to measure the velocity field, and finally with a combination of the two to acquire both fields at once. The results from this new technique will clarify the role of convective mixing in turbulent free shear flows. The award recommendation provides funds to cover international travel and a stipend for twelve months.

长期和中期研究：速度和集中度 湍流射流和逆流射流的测量 该奖项是根据长期和中期研究， 外国卓越中心计划，使美国 科学家和工程师将进行三到十二个月的 在国外经过验证的卓越研究中心进行研究。 的 该计划的奖项提供了联合研究的机会， 利用独特或互补的设施、专门知识和 国外的实验条件。 该奖项将支持为期十二个月的博士后研究访问 由斯坦福大学的南尤达博士与海因里希博士合作 菲德勒在柏林工业大学。 他们的研究 该项目涉及开发技术， 采集二维浓度场和速度场， 在湍流水流中的应用。 这项技术最初将 在一个基本的流动，轴对称射流， 评估其准确性和适用性。 他们将用他们的 技术研究射流逆流，一种新的流动， 因为它显示了从对流到绝对的转变 不稳定 在这两种情况下，他们的方法都涉及标记 首先用荧光染料流动， （被动标量）浓度场，然后与中性浮力 粒子来测量速度场，最后用 两者的结合，一次获得两个字段。 结果 将阐明对流混合的作用 在湍流自由剪切流中。 该奖项的建议提供资金，以支付国际 旅行和12个月的津贴