Numerical and Experimental Study of the Electrohydrodynamic Atomization of Highly Conducting Liquids, Including Dissipation Effects

高导电液体电流体动力学雾化（包括耗散效应）的数值和实验研究

• 批准号: 1604163
• 负责人: Manuel Gamero
• 金额: $ 18.02万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1604163&HistoricalAwards=false
• 关键词: Numerical; Experimental; Study; Electrohydrodynamic; Atomization

PI: Gamero, ManuelProposal Number: 1604163The goal of the proposed research is to advance theoretical understanding of the fluid dynamics involved in the process known as electrospraying. In this process, often utilized for the manufacturing of well-controlled nanodrops or nanofibers, highly conducting fluids pass through a cone-jet orifice. The proposed research is motivated by recent experimental data showing that energy dissipation is important in electrosprays of highly conducting fluids, especially when nanoscale drops are formed. Manufacturing and nanotechnology have been both identified as areas of National need. The objective of this project is to obtain a fundamental understanding of the electrospraying of highly conducting liquids in the cone-jet mode, with the novel inclusion of thermal effects. The importance of cone-jets of highly conductivity liquids resides in its unique ability for generating uniform sprays of nanodroplets, which are of great interest in manufacturing, spacecraft propulsion and hypervelocity impact research. Although electrospraying in the cone-jet mode has been analyzed on the bases of the leaky dielectric model, recent experimental work has demonstrated that energy dissipation is significant in the highly conductivity, nanometric regime, making it necessary to supplement the mechanical leaky dielectric model with an equation of conservation of energy to resolve the temperature field. Accounting for the actual variation of temperature is important because of the strong temperature dependence of key parameters like viscosity, electrical conductivity, and surface tension. This project will formulate and numerically solve a 2-D, axisymmetric electrohydrodynamic model of the transition region of cone-jets that retains thermal effects, and measure cone-jet characteristics (including the I(Q) law, and the dissipation of energy) with the goal of validating the model. The experimental measurements, in particular the measurement of energy dissipation, must be done in a vacuum environment using a combination of time of flight and retarding potential analyzers. The project includes two broader impact components: fundamental research while promoting teaching, training and learning; and promoting the participation of underrepresented groups. The proposed research will be infused into middle and high school students through: a) a collaboration with the local K-12 school district including the development of activities such as laboratory open-houses and occasional lectures on physics and technological applications associated with the proposed research; and b) summer internships for high school students to work on the NSF project.

PI: Gamero， manuel提案号：1604163提议的研究目标是推进理论理解的流体动力学过程中被称为电喷涂。在这个过程中，通常用于制造控制良好的纳米液滴或纳米纤维，高导电性流体通过锥形射流孔。最近的实验数据表明，能量耗散在高导电性流体的电喷雾中很重要，特别是当纳米级液滴形成时。制造业和纳米技术都被确定为国家需要的领域。本项目的目标是获得高导电性液体在锥形喷射模式下的电喷涂的基本理解，其中包含了新的热效应。高导电性液体的锥形射流的重要性在于其产生纳米液滴均匀喷雾的独特能力，这在制造业、航天器推进和超高速碰撞研究中具有重要意义。虽然已经在漏电介质模型的基础上分析了锥喷射模式下的电喷涂，但最近的实验工作表明，在高电导率的纳米状态下，能量耗散是显著的，因此有必要用能量守恒方程来补充机械漏电介质模型来求解温度场。考虑温度的实际变化是很重要的，因为粘度、电导率和表面张力等关键参数对温度的依赖性很强。本项目将建立并数值求解保留热效应的锥形射流过渡区域的二维轴对称电流体动力学模型，并测量锥形射流特性（包括I(Q)定律和能量耗散），以验证该模型。实验测量，特别是能量耗散的测量，必须在真空环境中使用飞行时间和延迟电位分析仪的组合来完成。该项目包括两个影响更广泛的组成部分：在促进教学、培训和学习的同时进行基础研究；促进弱势群体的参与。拟议的研究将通过以下方式灌输给初高中学生：a)与当地K-12学区合作，包括开展与拟议研究相关的实验室开放日和不定期的物理和技术应用讲座等活动；b)高中生在NSF项目上的暑期实习。