EAPSI: Establishing New Mathematical Methods for Analyzing Simulated Models of Fuel Combustion

EAPSI：建立新的数学方法来分析燃料燃烧模拟模型

• 批准号: 1613817
• 负责人: Rachel Levanger
• 金额: $ 0.54万
• 依托单位: Levanger Rachel L
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-15 至 2017-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1613817&HistoricalAwards=false
• 关键词: EAPSI; Establishing; New; Mathematical; Methods

A form of internal combustion called homogeneous-charge compression ignition (HCCI) results in relatively low emissions and high efficiency. The fuel and oxidizer are mixed and then compressed to the point of auto-ignition, though it is currently unknown how to control the exact timing of the ignition, an aspect that requires a precise understanding in order to be implemented commercially. Dr. Takashi Ishihara of Nagoya University has hypothesized that introducing stirring, or movement, in the fuel flow field will control the timing of the onset of ignition, and initial studies on simulated data support this idea. In this project, the EAPSI fellow will study 3D combustion simulations to understand how introducing a flow in the fuel chamber controls the timing of the onset of ignition. This investigation will require the development of new mathematical tools, which in turn will have further implications in problems of fluid analysis, e.g. weather simulations and the study of ocean currents.Numerical simulations of time-varying 3D fluid models tracking temperature, velocity, and chemical species, will be studied using a mathematical tool in topological data analysis called persistent homology. With this method, each time point in the simulation will generate a collection of mathematical objects called persistence diagrams, which encode the relationships of the critical points of the simulated data (e.g. local minima, maxima, and saddle points). This data will then be mined using established statistical techniques to uncover correlations with existing measurements of interest to physicists and gain insight into the mechanisms by which the dynamics of the fluid control the timing of the onset of ignition. This award under the East Asia and Pacific Summer Institutes program supports summer research by a U.S. graduate student and is jointly funded by NSF and the Japan Society for the Promotion of Science.

一种被称为均质充气压缩点火(HCCI)的内燃形式导致了相对低排放和高效率。燃料和氧化剂被混合，然后被压缩到自动点火的程度，尽管目前还不知道如何控制点火的准确时间，这一方面需要精确的理解才能在商业上实施。名古屋大学的Takashi Ishihara博士假设，在燃料流场中引入搅拌或运动将控制点火开始的时间，对模拟数据的初步研究支持这一想法。在这个项目中，EAPSI研究员将研究3D燃烧模拟，以了解在燃料室中引入流动如何控制点火开始的时间。这项研究将需要开发新的数学工具，这反过来将对流体分析问题产生进一步的影响，例如天气模拟和洋流研究。跟踪温度、速度和化学物种的时变3D流体模型的数值模拟将使用称为持久同源的拓扑数据分析中的数学工具进行研究。通过这种方法，模拟中的每个时间点将生成一个称为持久性图的数学对象集合，这些对象编码模拟数据的临界点(例如，局部极小值、极大值和鞍点)之间的关系。然后，将使用既定的统计技术来挖掘这些数据，以揭示与物理学家感兴趣的现有测量结果的相关性，并深入了解流体的动力学控制点火开始时间的机制。该奖项由东亚和太平洋暑期学院项目资助一名美国研究生的暑期研究，由NSF和日本科学促进会共同资助。