CAREER: Mixed-Integer Nonlinear Programming Approaches for Hydrogen Production Systems

研究：随着美国向氢经济转型，必须应对各种技术挑战。对于汽车燃料电池的应用，需要从液体燃料中高效地生产氢气。液体燃料重整制氢的方法必须考虑热相互作用、启动程序和操作条件变化，然后这些系统才能成为真正可行的能源替代品。有效的操作通常要求化学处理系统在不同的操作条件下和/或接近安全限制时良好地工作。化学反应系统可能会根据当前的操作条件表现出不同的动态行为(非线性动力学)，并且有时可以切换到本质上不同的操作模式(混合动力学)。本课题考虑具有过程安全约束的非线性混杂动态系统。所提出的方法需要计算包含未知变量的困难的数值优化问题，这些未知变量可以取连续值也可以取整数值(混合整数优化)。具体地说，考虑了用于制氢系统的非线性过程控制的确定性混合整数非线性优化技术的开发和应用。该项目还审查了在开发与研究有关的教育工具和学生方案方面将研究和教育结合起来，在国家和地方两级对学生产生影响。将开发过程控制教育软件，供全国推广。将利用以协作研究为基础的环境开发一个跨学科的本科过程控制实验室。在这里，现有的国家科学基金会赞助的本科生研究交流工作室和学生团体将鼓励注册，这些团体通常不会被系统工程职业所吸引，比如女性工程师协会和全国黑人工程师协会。最后，将启动一个外展计划，让研究生在该地区的高中进行工程演示。影响改进制氢系统运行的方法的开发和应用可能会产生广泛的社会影响，通过提高系统效率和加速采用新技术来帮助向氢经济过渡。为了支持氢气生产操作的改进，将考虑开发用于复杂的非线性动态系统的新的化工过程控制方法。这些概念的发展可能会对整个化学工业产生持久的影响，此外还会改善制氢系统的运行。最后，改进的通用确定性混合整数非线性规划求解方法的发展可能会产生跨越科学和工程学科的影响。

Research:As the United States makes the transition to a hydrogen economy, various technical challenges must be met. For vehicle fuel cell applications, a need exists for efficient production of hydrogen from liquid fuels. Liquid fuel reformer methods for hydrogen production must consider thermal interaction, startup procedures, and operating condition changes before these systems can become a truly viable energy alternative. Efficient operation often requires that chemical processing systems work well in different operating conditions and/or close to safety limitations. Chemical reaction systems may exhibit varied dynamic behavior based on the current operating conditions (nonlinear dynamics) and can sometimes switch to qualitatively different modes of operation (hybrid dynamics). This project considers nonlinear hybrid dynamic systems and with process safety constraints. The proposed methods require computational solution of difficult numerical optimization problems involving unknown variables that may take either continuous or integer values (mixed-integer optimization). Specifically, development and application of deterministic mixed-integer nonlinear optimization techniques for nonlinear process control applied to hydrogen production systems are considered. This project also examines integration of research and education in the development of research-related educational tools and student programs with student impact at both the national and local level. Process control educational software will be developed for national dissemination. A cross-disciplinary undergraduate process control laboratory will be developed using a collaborative research-based environment. Here, enrollment would be encouraged from an existing National Science Foundation sponsored undergraduate research communication studio and student groups not normally drawn to systems engineering careers such as the Society of Women Engineers and National Society of Black Engineers. Finally, an outreach program will be started with graduate students presenting engineering demonstrations in area high schools. Impact Development and application of methods for improved operation of hydrogen production systems may have broad societal impact, aiding the transition to a hydrogen economy by improving system efficiency and speeding adoption of new technologies. In support of improved hydrogen production operation, development of novel chemical process control methods for complex nonlinear dynamic systems will be considered. Development of these concepts may have lasting effects across the chemical industry, in addition to improved hydrogen production system operation. Finally, development of improved general purpose deterministic mixed integer nonlinear programming solution methods may have impact across scientific and engineering disciplines.