Collaborative Research: Plasma-enhanced Electrostatic Precipitation of Diesel Particulates using High Voltage Nanosecond Pulses

合作研究：使用高压纳秒脉冲对柴油颗粒进行等离子体增强静电沉淀

• 批准号: 2112881
• 负责人: Heejung Jung
• 金额: $ 21万
• 依托单位: University of California-Riverside
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2112881&HistoricalAwards=false
• 关键词: Collaborative; Research; Plasma; enhanced; Electrostatic

The adverse health effects of diesel engine particulate emissions have been firmly established by many toxicological studies over the past few decades. These fine particulates smaller than 2.5 microns have been linked to premature cardiovascular and respiratory deaths, as well as lung cancer. While electrostatic precipitation was first demonstrated in 1824, thus far, use of the technology to remove combustion particulates has been limited to large power plants that can accommodate large secondary treatment devices. Reducing the overall size of this technology is necessary to open up new applications for electrostatic precipitation in mobile sources, such as ships and trucks. Our approach to electrostatic precipitation using plasma (a superheated state of matter) together with ultra-high frequency high voltage pulsing represents a novel application of an old technology. Preliminary results have shown significant promise in reducing particulate emissions, but the underlying mechanisms are poorly understood. The goal of this project is to address these knowledge gaps and identify the mechanisms for particulate removal in plasma enhanced electrostatic precipitation. If successful, this approach will enable development of much more compact electrostatic precipitators that could potentially transform diesel particulate mitigation technology for mobile sources. Further benefits to society result from outreach to high school teachers in the Los Angeles area to improve STEM teaching for underrepresented students. Outreach through professional societies will improve chemistry teaching and provide research opportunities for undergraduate students, thus improving scientific literacy.Preliminary results by the research team show that nanosecond high voltage pulsed plasma provides significant enhancement over conventional electrostatic precipitators in removing diesel engine particulates. However, the fundamental mechanism(s) underlying this enhancement remain poorly understood. The overall goal of this research is to explore the application of plasma enhanced nanosecond high voltage pulsed discharges as a novel approach for electrostatic precipitation. The specific research objectives designed to achieve this goal include: i) spectroscopic examination of ion mobilities and species generated by nanosecond high voltage pulse discharge, ii) characterization of size-dependent particle charge distributions, iii) multi-physics computational fluid dynamics modeling of nanosecond high voltage pulse electrostatic precipitation, and iv) investigation of the role of streamers in the ESP process. Results from this systematic study will provide mechanistic insight into the plasma enhanced electrostatic precipitation process. Such information is necessary to design systems to overcome current limitations and further improve particle removal efficiency. The nature of this work is inherently interdisciplinary, involving high voltage electronics, electrostatics, and fluid-dynamics, as well as combustion and aerosol science. This project brings together researchers with complimentary expertise to perform the research, as well as provide collaborative training opportunities for the student researchers.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.

在过去的几十年中，许多毒理学研究已经牢固地确定了柴油发动机颗粒物的不利影响。这些细小的微粒小于2.5微米已与心血管过早和呼吸道死亡以及肺癌有关。虽然静电沉淀在1824年首次证明，但到目前为止，使用该技术去除燃烧颗粒已限于可以容纳大型次要处理装置的大型发电厂。减少这项技术的整体规模对于开放移动源（例如船舶和卡车）的静电降水的新应用是必要的。我们使用血浆（物质的过热状态）以及超高频率高电压脉冲的静电沉淀方法代表了旧技术的新应用。初步结果在减少颗粒物排放方面表现出了巨大的希望，但基本机制知之甚少。该项目的目的是解决这些知识差距，并确定血浆增强静电沉淀中颗粒物去除的机制。如果成功的话，这种方法将能够开发更紧凑的静电阻止者，从而有可能改变移动源的柴油颗粒缓解技术。洛杉矶地区的高中教师外展对社会的进一步好处，以改善代表性不足的学生的STEM教学。通过专业社会的外展活动将改善化学教学，并为本科生提供研究机会，从而提高科学素养。研究团队的最佳结果表明，纳秒高电压脉冲等离子体可在去除柴油发动机颗粒方面对传统的静电降水剂进行显着增强。但是，这种增强的基本机制仍然鲜为人知。这项研究的总体目标是探索血浆增强的纳秒高压脉冲放电作为静电沉淀的新方法。旨在实现此目标的具体研究目标包括：i）纳米秒高电压脉冲排放产生的离子迁移率和物种的光谱检查，ii）依赖大小依赖粒子电荷分布的表征，iii）多物理计算流体流体动力学动力学模型，对纳米秒高电压脉冲脉冲静电量沉淀和iv）的研究。这项系统研究的结果将提供有关血浆增强静电沉淀过程的机械洞察力。这些信息对于设计系统以克服当前局限性并进一步提高粒子去除效率是必要的。这项工作的性质本质上是跨学科的，涉及高压电子，静电和流体动力学，以及燃烧和气溶胶科学。该项目汇集了具有免费专业知识的研究人员来进行研究，并为学生研究人员提供了协作培训机会。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和更广泛影响的评估评估标准通过评估来支持的。