SBIR Phase I: Multi-Environment Probability Density Function (PDF) Method for Modeling Turbulent Combustion Using Detailed Chemistry

该小型企业创新研究（SBIR）第一阶段项目将研究应用多环境概率密度函数（MEPDF）方法的适用性和优点，以在实际燃烧设备的综合CFD模拟中模拟具有现实化学动力学的湍流燃烧问题。 MEPDF保留了传输概率密度函数（PDF）方法的许多理想特性，但计算成本仅为一小部分，包括能够精确处理化学源项，并以极高的精度解决湍流和有限速率化学反应之间的非线性相互作用。 MEPDF起源于多环境微观混合模型，用于化学工程界模拟几乎没有热释放的化学过程。 最近，这种方法已扩展到模拟气相燃烧问题，但只有非常简单的化学。该项目旨在通过将其扩展到结合用于模拟燃烧问题的现实化学动力学来进一步推进该方法，在该燃烧问题中，惰性-有限速率反应相互作用对于准确预测污染物排放（例如，NOx、煤烟）。 这项工作最终将MEPDF方法扩展到模拟非均相燃烧问题，如煤燃烧，并提供手段来模拟低NOx燃烧系统，广泛应用于发电industry.The活动的MEPDF方法模拟实际燃烧系统使用复杂的化学动力学将导致一个坚实的基础的科学和工程知识和理解基础。 一个改进的建模工具，以提供更可靠的预测复杂的燃烧过程的价值是清楚地证明了来自各个行业的商业关注。 该项目开发的先进工具为发电、化学加工、矿物加工和焚烧行业的公司提供了改进产品设计和服务的手段，最终有利于环境、全球竞争力和国家/国土安全。 目前，对污染物形成和破坏过程的了解受到精确模拟这些复杂过程的能力的限制，如果能更好地了解这些过程，将有助于减少污染物的排放。 减少发电厂、工艺炉和焚烧炉的污染物排放将继续是一个必要的环境目标，也是一个具有挑战性的工程问题，需要尽可能最好的研究工具。

This Small Business Innovation Research (SBIR) Phase I project will investigate the applicability and merit of applying the multi-environment probability density function (MEPDF) method to model turbulent combustion problems with realistic chemical kinetics within comprehensive CFD simulations of practical combustion equipment. MEPDF retains many of the desirable properties of the transported probability density function (PDF) method but at a fraction of the computational cost, including the ability to treat the chemical source term exactly and address the nonlinear interaction between turbulence and finite rate chemical reactions with great accuracy. MEPDF originated from multi-environment micro-mixing models used in the chemical engineering community to simulate chemical processes with little heat release. Recently this method has been extended to model gas phase combustion problems, but for only very simple chemistry. This project aims to further advance this method by extending it to incorporate realistic chemical kinetics for modeling combustion problems where turbulent-finite rate reaction interaction is crucial for accurate prediction such as pollutant emission (e.g., NOx, soot). The work would eventually extend the MEPDF method to model heterogeneous combustion problems, such as coal combustion, and provide means to simulate low NOx firing systems that are widely used in the power generation industry.The activities of extending the MEPDF method to simulate practical combustion systems using complex chemical kinetics would lead to a solid foundation of the scientific and engineering knowledge and understanding base. The value of an improved modeling tool to provide more reliable predictions of complex combustion processes is clearly evidenced by commercial concerns from various industries. The development of advanced tools from this project provides means for companies in the power generation, chemical process, mineral process, and incineration industries to improve product designs and services that would ultimately benefit the environment, global competitiveness, and national/homeland security. An improved understanding of pollutant formation and destruction processes, currently limited by the ability to accurately model these complex processes, will result in reductions of pollutant emissions. Reducing pollutant emissions from power plants, process furnaces, and incinerators will continue to be both a necessary environmental objective and a challenging engineering problem requiring the best investigational tools possible.