Particle Image Baro-Velocimetry (PIBV): simultaneous measurement of pressure and velocity in fluids

粒子图像气压测速 (PIBV)：同时测量流体中的压力和速度

• 批准号: 1332204
• 负责人: Maurizio Porfiri
• 金额: $ 27万
• 依托单位: New York University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1332204&HistoricalAwards=false
• 关键词: Particle; Image; Baro; Velocimetry; PIBV

Porfiri, Maurizio 1332204 This proposal addresses the grand challenge of enabling, for the first time, direct and simultaneous full-field measurement of the instantaneous pressure and velocity in a fluid flow. The proposed methodology will transform current experimental fluid mechanics practices by providing US academic, industrial, and government institutions with the capability of performing local sensing in real time of kinematics and kinetics of fluid flow fields. While the proposed framework is transformative in nature, its practical implementation requires minimal upgrades to established fluid mechanics measurement systems. Specifically, this proposal encompasses the formulation and incorporation of novel pressure-sensitive tracer particles into traditional Particle Image Velocimetry (PIV) systems towards a novel Particle Image Baro-Velocimetry (PIBV) system. The proposed microcapsules will comprise air encapsulated in highly compliant biocompatible hydrogel shells that are specifically formulated to fluoresce with different wavelength distributions, that is, to change color, depending on the strain of the hydrogel shell. Pressure acting upon the particle modifies its volume, which, in turn, results in a measurable change in the fluorescent response. The response time of the probes to a step change in pressure is expected to be on the order of a microsecond. Further, the hydrogel microprobe design can be tailored to the experiment to optimize sensitivity over a prescribed pressure range and detect pressure levels as low as the order of ten pascals. Utilizing these novel microscale particles as tracers, the velocity field within a fluid can be measured using traditional PIV techniques without a loss of flow tracing fidelity or an increase in overall measurement uncertainty.Intellectual Merit :The intellectual merits of this project include: (i) establishing a novel measurement system that will enable full characterization of the pressure and velocity fields of complex fluid flow scenarios; (ii) designing, synthesizing, and calibrating a new class of biocompatible pressure microprobes based on hydrogels; (iii) formulating and experimentally validating mechanics-based theoretical and computational models of air-encapsulated hydrogel spheres in fluids; and (iv) assessing PIBV potential through direct pressure measurement in state of the art studies on biomimetic propulsion, hydrodynamic damping, and internal flows.Broader Impacts :Effective technologies for simultaneous characterization of flow kinematics and kinetics will benefit multiple scientific and engineering communities within academic, industrial, and government institutions and positively impact several applied and fundamental research fields. This project will reinforce technical training and education of the socioeconomically diverse student body in Brooklyn, New York. A suite of teaching modules for middle and high school students demonstrating various principles of fluid mechanics will be developed and implemented in classroom education through synergy with current NSF programs (RET site and GK-12 program). The project will also contribute to the removal of mental barriers across the extremal student populations defining the spectrum of metropolitan versus rural backgrounds in Brooklyn and Waterloo, Ontario by supporting the summer research experience for US students in the University of Waterloo. A one-day instructional short course on PIBV systems will be hosted at the Polytechnic Institute of New York University with emphasis on the measurement principle and uncertainty, data acquisition and processing, and integration into PIV systems. A wiki page about the project will be developed for outreach to the public and promoting PIBV.

Porfiri, Maurizio 1332204 该提案解决了首次实现流体流动中瞬时压力和速度的直接同步全场测量的巨大挑战。所提出的方法将通过为美国学术、工业和政府机构提供对流体流场的运动学和动力学进行实时局部传感的能力来改变当前的实验流体力学实践。虽然所提出的框架本质上是变革性的，但其实际实施需要对已建立的流体力学测量系统进行最少的升级。具体来说，该提案包括将新型压敏示踪剂粒子配制并纳入传统粒子图像测速（PIV）系统中，以实现新型粒子图像气压测速（PIBV）系统。所提出的微胶囊将包含封装在高度顺应性生物相容性水凝胶壳中的空气，这些水凝胶壳经过专门配制，可发出不同波长分布的荧光，即根据水凝胶壳的应变改变颜色。作用在颗粒上的压力会改变其体积，从而导致荧光响应发生可测量的变化。探头对压力阶跃变化的响应时间预计为微秒量级。此外，水凝胶微探针设计可以根据实验进行定制，以优化规定压力范围内的灵敏度，并检测低至十帕斯卡量级的压力水平。利用这些新颖的微米级颗粒作为示踪剂，可以使用传统的 PIV 技术测量流体内的速度场，而不会损失流量追踪保真度或增加总体测量不确定性。 智力优点：该项目的智力优点包括：（i）建立一种新颖的测量系统，能够全面表征复杂流体流动场景的压力和速度场； (ii) 设计、合成和校准一类基于水凝胶的新型生物相容性压力微探针； (iii) 制定并通过实验验证流体中空气封装水凝胶球的基于力学的理论和计算模型； (iv) 在仿生推进、流体动力阻尼和内部流动的最先进研究中通过直接压力测量来评估 PIBV 潜力。 更广泛的影响：同时表征流动运动学和动力学的有效技术将有利于学术界的多个科学和工程界、工业和政府机构，并对多个应用和基础研究领域产生积极影响。该项目将加强纽约布鲁克林社会经济多元化学生群体的技术培训和教育。通过与当前 NSF 项目（RET 站点和 GK-12 项目）的协同，将开发一套针对中学生和高中生的教学模块，展示流体力学的各种原理并在课堂教育中实施。该项目还将通过支持美国学生在滑铁卢​​大学的暑期研究体验，帮助消除极端学生群体的心理障碍，这些学生群体定义了布鲁克林和安大略省滑铁卢的大都市与农村背景。纽约大学理工学院将举办为期一天的 PIBV 系统教学短期课程，重点是测量原理和不确定性、数据采集和处理以及与 PIV 系统的集成。将开发一个有关该项目的 wiki 页面，以向公众进行宣传并推广 PIBV。

项目成果

An information-theoretic study of fish swimming in the wake of a pitching airfoil

鱼在俯仰翼型后游动的信息论研究

• DOI: 10.1016/j.physd.2019.02.014
• 发表时间: 2019-09
• 期刊: Physica D: Nonlinear Phenomena
• 作者: Zhang, Peng;Krasner, Elizabeth;Peterson, Sean D.;Porfiri, Maurizio
• 通讯作者: Porfiri, Maurizio