Numerical Characterization of Effects of Addition of H2, CO, CO2 and H2O in High-Pressure Premixed Turbulent Flames

全球环境问题日益要求严格控制排放。这对发电行业来说是非常重要的。因此，重点转向了超低排放技术。相应地，燃烧工程师和科学家正在从非预混燃烧转向预混燃烧装置。提出的项目旨在提高对预混湍流燃烧基本方面的物理认识，即：(i)多组分燃料/空气混合物预混湍流火焰发展的大涡模拟研究，（ii）高压对湍流燃烧速度的影响，以及（iii）分子传递效应（刘易斯数和优先扩散）对预混火焰特性的影响。具体来说，它将检验上述三个因素对火焰特性的影响。该研究将侧重于向碳氢化合物混合物、生物燃料和合成气中添加稀释剂（H2、CO、CO2和H2O）。在工作的第二阶段，将开发一个用于稀释剂/碳氢化合物/空气混合物的通用湍流反应流模型，并在独立的实验数据库中进行验证。数值研究将采用先进的大涡模拟技术，并将纳入各种燃烧模型。这项工作所产生的任何改进设备都将扩大能源多样化的范围。这项研究的进展将使英国工业部门能够率先制定燃烧应用的设计指南。此外，它还具有满足欧洲共同体在实现不使用矿物燃料方面的战略目标的优点。

Global environmental concerns impose an increasing demand for stringent control of emissions. This is of pressing importance to the power generation sector. Accordingly, the emphasis has shifted to ultra-low emission technology. Correspondingly, combustion engineers and scientists are moving away from nonpremixed combustion to premixed combustion devices.The proposed project is aimed at improving the physical understanding of the fundamental aspects of premixed turbulent combustion, namely, (i) large-eddy simulation investigation of premixed turbulent flame development of multi-component fuel/air mixtures, (ii) influence of high-pressure on turbulent burning velocities, and (iii) the molecular transport effects (the Lewis number and preferential diffusion) on premixed flame characteristics. Specifically, it will examine the above named effect of the three factors on the flame characteristics. The study will focus on addition of diluents (H2, CO, CO2 and H2O) to hydrocarbon mixtures, biofuels and synthetic gas. In the second phase of the work, a universal turbulent reacting flow model for diluent/hydrocarbon/air mixtures will be developed and validated against independent experimental databases.Numerical investigations will be undertaken using advanced large-eddy simulation technique and will incorporate a variety of combustion models. Any improved devices arising from this work will enhance the scope for diversifying energy resources. Advances resulting from this study should enable the UK industrial sector to take a lead in developing design guidelines for combustion applications. Additionally, it has the merit of meeting the strategic objectives of the European Community in achieving independence from the use of fossil fuels.