Excellence in Research: Co-axial Flow Mixing and Control using Ultra-High Frequency Actuators

卓越的研究：使用超高频执行器的同轴流混合和控制

基本信息

批准号：
1900177
负责人：
John Solomon
金额：
$ 50万
依托单位：
Tuskegee University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-08-01 至 2024-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1900177&HistoricalAwards=false
关键词：
Excellence Research Co axial Flow

项目摘要

Innovative fuel-air mixing technologies are essential to the continual advancement of faster and more reliable aircrafts for both national defense and air transportation. This project will focus on a novel fuel injection scheme to enhance and control mixing of a fluid (fuel) with a fast moving air. The proposed scheme consists of two co-axial nozzles: a central nozzle surrounded by an annular one, through which air and fluid are injected simultaneously. While the fluid is supplied through the annular nozzle in a steady stream, the central nozzle injects air in a pulsed manner to enhance mixing. The innovative concept for the proposed injection system is in its ability to pulse the central air jet at very high frequencies (20,000-30,000 pulses per second). It is anticipated that the fluid (fuel) and the high frequency pulsed air will be mixed more effectively in this manner. To investigate this, an experimental fluid mechanics research lab will be equipped with new capabilities utilizing the state-of-the-art, advanced laser-based flow diagnostics that are required for this study. The project will also use educational plans that have been developed based upon established learning theories to provide more effective research experience to underrepresented students in engineering.Major goals of this project include design, development, and characterization through fundamental studies of an active co-flow injection system for enhanced fuel-air mixing at high speeds. The proposed system consists of a supersonic actuation air jet at the inner core that provides large mean and fluctuating velocity profiles in the shear layer of a steadily-injected annular fluid, where the fluctuations occur at a designated and controllable ultra-high frequency. It is expected that the mixing of air with the co-flowing fluid can be improved and controlled using resulting stream-wise vortices that are tailored to the mean flow in this manner. The specific tasks include quantitative characterization of mixing through measurement of seed particle density distribution using planar laser-induced florescence (PLIF) and velocity and vorticity field measurement using particle image velocimetry (PIV). Using these data, the diffusive mixing characteristics of the system (e.g., the timescales of evolution, interfacial area generation and mixing efficiency) will be studied and correlated to the relevant non-dimensional parameters involved. Specific educational activities include targeted infusion of advanced topics useful in research to an undergraduate level fluid mechanics course which provides additional support, and access to students whose pre-college situations may otherwise preclude success in engineering research.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

创新的燃油空气混合技术对于在国防和航空运输方面不断提高更快，更可靠的飞机至关重要。该项目将重点介绍一种新型的燃油喷射计划，以增强和控制流体（燃料）与快速移动的空气的混合。提出的方案由两个同轴喷嘴组成：一个环形喷嘴包围的中央喷嘴，同时注入空气和流体。虽然流体是通过稳定流的环形喷嘴提供的，但中央喷嘴以脉冲方式注入空气以增强混合。拟议的注射系统的创新概念在于其能够以非常高的频率脉冲中央空气飞行器（每秒20,000-30,000脉冲）。预计以这种方式将流体（燃料）和高频脉冲空气更有效地混合。为了调查这一点，通过本研究所需的最先进的基于激光的流动诊断，将配备一个实验流体力学研究实验室。该项目还将使用基于既定的学习理论制定的教育计划，以提供更有效的研究经验为工程领域的代表性不足的学生提供。该项目的目标包括设计，开发和表征通过对主动共汇注射系统的基本研究，以增强高速燃油空气混合。所提出的系统由内芯处的超音速驱动空气射流组成，该气流在稳定注射的环形流体的剪切层中提供了较大的均值和波动的速度曲线，在该剪切层中，波动以指定的和可控制的超高频率发生。可以预期，可以使用以这种方式量身定制的流式涡流将空气与共同流体的混合进行改进和控制。特定任务包括使用平面激光诱导的荧光（PLIF）来测量种子颗粒密度分布的定量表征以及使用颗粒图像速度（PIV）的速度和涡度场测量。使用这些数据，将研究系统的扩散混合特性（例如，进化，界面面积的产生和混合效率）并与涉及的相关非二维参数进行研究并相关。具体的教育活动包括针对研究的有针对性的高级主题对本科水平的流体力学课程有用，该课程提供了额外的支持，并访问其前大学情况下可能会排除工程研究成功的学生。该奖项反映了NSF的法定任务，并通过使用该基金会的知识优点和广泛的范围来评估来表现出值得通过评估的支持。