MRI: Acquisition of Laser Flow Measurement Instrumentation for Fluid Mechanics Research

最近商业化的一项新实验技术测量了时间分辨的三维流体流动速度场。这项革命性的技术为湍流的物理细节提供了前所未有的途径。新仪器将用于拉斐特学院现有的研究血管流动的实验室，以及正在建造的用于研究湍流边界层中相干结构的新水道设施。该请求将升级现有的二维粒子图像测速（PIV）系统，该系统于2006年在美国国家科学基金会的支持下购买（MRI奖CTS-0618923），通过层析重建技术增加完全三维速度场测量的能力。为了补充PIV相对较低的采样频率，要求中包括一个激光多普勒测速系统。LDV系统记录的高频点方向数据可以提供准确的湍流统计数据，这些数据需要适当地缩放和量化湍流，并获得用PIV无法建立的速度能谱。LDV的设计能够与PIV系统同时记录，还将为新兴的3-D PIV技术提供关键的验证测量。这一要求的仪器将扩大研究人员的研究集中，并扩大研究培训和研究机会提供给拉斐特学院的本科生。

1040236SabatinoA new recently commercialized experimental technique measures time-resolved three-dimensional fluid-flow velocity fields. This revolutionary technology provides unprecedented access to the details of the physics of turbulent flows. The new instrumentation will be utilized both in an existing laboratory at Lafayette College that investigates flow through blood vessels as well as in a new water channel facility that is being constructed for the investigation of coherent structures in turbulent boundary layers. This request will upgrade an existing two-dimensional particle image velocimetry (PIV) system that was purchased with NSF support in 2006 (MRI award CTS-0618923) to add the capability for fully three dimensional velocity field measurements by means of a tomographic reconstruction technique. To complement the relatively low sampling frequency of the PIV, a laser Doppler velocimetry (LDV) system is included in the request. The LDV system records high frequency point-wise data which can provide accurate turbulent statistics that are required to properly scale and quantify the turbulent flows, as well as obtain velocity energy spectra which cannot be established with the PIV. Designed to be able to record simultaneously with the PIV system, the LDV will also provide critical validation measurements for the emerging 3-D PIV technique. This requested instrumentation will extend the research concentrations of the investigators and expand the research training and research opportunities available to undergraduate students at Lafayette College.