Collaborative Research: High-speed Imaging Guided Large Eddy Simulation (LES) Model Development for Turbulent Flames

1403969/1403901 Meyer/Raman合作研究：高速成像制导的湍流火焰大涡模拟模型开发拟议的研究努力是为通常嵌入到湍流中的实际火焰开发计算机模型，例如飞机发动机和发电厂中的火焰。本文开发的改进的建模工具可以扩展到许多其他领域，如烟尘模拟、火灾模拟、地球物理流体动力学和环境科学。此外，首席研究人员将继续指导不同的高中和本科生研究人员群体，以吸引他们并为他们在科学和工程领域的研究生职业生涯做好准备。全面了解火焰稳定对于未来电力、推进和运输系统的清洁和高效燃烧至关重要。在这种背景下，大涡模拟(LES)方法为模拟火焰稳定和相关的燃烧动力学提供了一个合适的框架。然而，当前的大涡模拟模型远不理想，并且引入了可能改变模拟中的时间动力学的简化。在这里，大涡模拟方法将被重新表述，以引入时间统计和非平衡耗散率。同时，高速成像数据将与超大规模直接数值模拟相结合，以验证统计数据和大涡模拟模型中的中心假设。一个行业合作伙伴将与研究团队合作，以确保模型和实验数据的相关性。教育和宣传部分将有助于将新知识和技术转移到课堂和行业。拟议工作的学术价值在于提供了对火焰稳定化的全面理解，而不是典型的一点、集合统计平均，并将使稳健和预测性计算模型的发展成为可能。它将利用基于高速激光成像和域名系统的最新进展来扩大大涡模拟方法的适用范围。这里开发的CFD模型和实验数据将提供给燃气轮机行业和久负盛名的湍流非预混火焰(TNF)国际工作组。

1403969/1403901Meyer/RamanCollaborative Research: High Speed Imaging Guided Large Eddy Simulation Model Development for Turbulent FlamesThe proposed research effort is to develop computer models for practical flames that are usually embedded in turbulent flows such as those in aircraft engines and power generation plants. The improved modeling tools developed here can be extended for use in many other fields such as soot modeling, fire simulations, geophysical fluid dynamics, and environmental sciences. The principal investigators will furthermore continue their practice of mentoring a diverse group of high-school and undergraduate researchers to attract and prepare them for graduate careers in science and engineering.A comprehensive understanding of flame stabilization is critical for clean and efficient combustion in future power, propulsion, and transportation systems. In this context, the large eddy simulation (LES) methodology provides a suitable framework for modeling flame stabilization and related combustion dynamics. However, current LES models are far from ideal and introduce simplifications that potentially alter the temporal dynamics in the simulations. Here, the LES modeling approach will be reformulated to introduce temporal statistics and a non-equilibrium dissipation rate. Simultaneously, high-speed imaging data will be combined with very large-scale direct numerical simulations (DNS) to validate central assumptions in the statistical data and LES model. An industry partner will collaborate with the research team to ensure the relevance of models and experimental data. Educational and outreach components will aid the transfer of new knowledge and technologies to the classroom and industry. The intellectual merit of the proposed work lies in providing a comprehensive understanding of flame stabilization beyond typical one-point, ensemble statistical averages and will enable the development of a robust and predictive computational modeling. It will take advantage of recent advances in high-speed laser-based imaging and DNS to expand the range of applicability of the LES modeling approach. The CFD models and experimental data developed here will be made accessible to the gas turbine industry and the well-established international working group on turbulent non-premixed flames (TNF).