A System Dynamics Modeling Methodology to Predict Transient Phenomena in Compressible Fluid Flow Systems

这项建议将系统动力学和控制方面的专业知识与流体力学和发动机建模方面的专业知识相结合，以开发一种系统的方法来模拟可压缩流体流动系统中的瞬变现象。这样的方法在今天是不存在的。该项目的成功成果将是能够系统地对描述可压缩流体流动的分布参数系统进行模型降阶，类似于现有的方法，例如用于机械系统。开发物理上一致的可压缩流动系统集中参数模型的能力将使内燃机、涡轮机械、燃料电池系统、暖通空调和制冷系统等能源转换系统的控制得到改进，从而实现更好的性能、降低成本和减少对环境的影响。鉴于政府对接近零排放的汽车的要求越来越严格，市场对汽车的需求也越来越高，汽车行业正在努力提高发动机的燃油经济性，减少排放。众所周知，只有在发动机设计的改进与严格控制发动机效率和排放的能力相匹配的情况下，才能实现这样的收益。目前的项目将带来更好的燃油经济性和排放控制，但也将大大缩短新的、更高效和更清洁的发动机的开发。今天，这个过程是非常特别的，它需要大量的实验校准。拟议项目的成果是一种系统化和广泛适用的方法，将缩短开发时间，并将导致强大的发动机控制设计，也将易于在发动机平台之间移植。该项目涉及来自代表性不足群体的荣誉本科生的大量参与，以及与德国斯图加特大学的国际合作。

This proposal integrates expertise in system dynamics and control with expertise in fluid mechanics and engine modeling to develop a systematic approach to modeling transient phenomena in compressible fluid flow systems. Such a methodology does not exist today. The successful outcome of this project will be the ability to systematically carry out model order reduction for distributed parameter systems that describe the flow of compressible fluids, in analogy with existing methods available, for example, for mechanical systems. The ability to develop physically consistent lumped-parameter models of compressible flow systems will enable improvements in the control of energy conversion systems such as internal combustion engines, turbomachinery, fuel cell systems, HVAC and refrigeration systems, leading to better performance, reduced costs and reduced environmental impact. The automotive industry is striving to improve engine fuel economy and to reduce their emissions in view of increasingly stringent government mandates and market demand for vehicles with near-zero exhaust emissions and significantly improved fuel economy. It is well understood that such gains can only be achieved if improvements in engine design can be matched by the ability to closely control engine efficiency and emissions. The present project will lead to better fuel economy and emissions control, but will also significant shorten the development of new, more efficient and cleaner engines. Today, this process is very much ad-hoc and it requires significant amounts of experimental calibration. The outcome of the proposed project is a systematic and widely applicable methodology that will shorten development time and that will lead to robust engine control designs that will also be easily portable among engine platforms.The project involves significant participation of Honor undergraduate students from under-represented groups, and an international collaboration with the University of Stuttgart, Germany.