MRI: Development of a Spatiotemporal Velocimetry with Simultaneous Size Measurements for Polydispersed Multi-Phase Flows

cts - 0521102 p。该资助旨在开发一种独特的仪器系统，用于在多分散多相流中进行空间分辨、同时速度和粒度测量，时间分辨率为kHz。该系统将用于生物流体力学、环境水力学和涡轮机械流动。这些看似不相关的流体力学领域都有一个基本需求，即解决与流体运动以及多分散颗粒在各向异性流动中的运动有关的未解问题，这些各向异性流动由湍流或不稳定控制，包括广泛的流动规模和结构。现有仪器无法提供具有足够采样频率的时空分辨测量，无法在测量颗粒尺寸和尺寸分布的同时捕捉湍流波动。新的时间分辨数字粒子图像测速仪（TRDPIV）仪器将提供硬件和算法的进步，以克服多分散多相流测量中存在的实验挑战。新系统结合了传统DPIV在空间上解析流体的优势，激光多普勒测速或热线测量高频速度波动的优势，以及相位多普勒粒子风速测量测量颗粒尺寸的优势。在这项资助下开发的仪器将对实验流体力学界产生直接而广泛的影响。多相流，如颗粒输送和碰撞、混凝、浮选、喷雾雾化和气泡动力学，存在于化学、航空/航天、海军、发电、汽车和生物医学等各种行业中。一种新的独特的测量能力将提供给所有这些领域的研究人员和工程师，从而对国家的工业和研究基础设施产生间接但非常广泛的影响。通过重点突出的努力，促进本科生和研究生在招募代表性不足的妇女和少数民族方面的研究，将对多样性产生广泛和直接的影响。通过对将开发和使用拟议系统的研究生和本科生进行全面培训和指导，将实现教育影响。更广泛的教育影响将扩展到研究生和本科生的教室，该系统将用于教授先进的实验方法，并在我们所需的流体力学课程中进行演示。

CTS-0521102P. Vlachos, Virginia Polytechnic InstituteThis grant is to develop a unique instrumentation system for spatially resolved, simultaneous velocity and particle size measurements in polydispersed multi-phase flows with kHz temporal resolution. The system will be used in biofluid mechanics, environmental hydraulics, and turbomachinery flows. These seemingly unrelated areas of fluid mechanics share the fundamental need to address unanswered questions relating the fluid motion along with the motion of polydispersed particulates in anisotropic flows that are governed by turbulence or unsteadiness encompassing a wide range of flow scales and structures. Existing instrumentation fails to deliver spatio-temporally resolved measurements with sufficient sampling frequency to capture turbulent fluctuations while simultaneously measuring the particulate size and size distribution. The new Time Resolved Digital Particle Image Velocimeter (TRDPIV) instrumentation will deliver hardware and algorithm advancements to overcome the experimental challenges present in polydispersed multiphase flow measurements. The new system combines the advantages of conventional DPIV to spatially resolve a flow with the advantages of Laser Doppler Velocimetry or hot-wires to measure high frequency velocity fluctuations and the advantages of Phase Doppler Particle Anemometry to measure particle sizes. The instrumentation developed under this grant will have a direct and broad impact upon the experimental fluid mechanics community. Multi-phase flows such as particle transport and collision, coagulation, flotation, spray atomization and bubble dynamics are present in a wide variety of industries such as chemical, aeronautical/aerospace, naval, power generation, automotive and biomedical. A new unique measurement capability will be available to researchers and engineers in all these areas thus having an indirect yet very broad impact on the nation's industrial, and research infrastructure. Broad and direct impact on diversity will be achieved through well-focused efforts to promote undergraduate and graduate research in recruiting underrepresented women and minorities. Educational impact will be achieved through thorough training and mentoring of graduate and undergraduate students that will be developing and using the proposed system. The broader educational impacts will extend to the graduate and undergraduate classrooms where the system will be used for teaching advanced experimental methods and performing demonstrations in our required fluid mechanics courses.