Numerical investigation of combustion process in gas fireplaces

拿破仑的母公司沃尔夫钢铁有限公司正在改进现有的燃气壁炉并开发新产品，以满足消费者对高效、清洁、美观的采暖产品不断增长的市场需求。目前的设计方法依赖于某些特定燃烧器多年来积累的经验知识。然而，基于严格的燃烧研究，还没有得出对任何类型的燃烧器和燃料都有效的系统方法。除了大气污染物的形成涉及复杂的化学成分外，气体壁炉的理想优化运行在很大程度上取决于燃烧器的设计和可供燃烧的空气量。拟议的研究目的是调查燃烧器几何形状和运行变量之间的复杂关系及其对热值、火焰外观和大气排放的影响。拟议的调查将使用计算流体动力学(CFD)进行，该技术在较短的周转时间内提供详细信息，与实验研究相比，成本低得多。最终结果将提供有关燃烧室内流体流动的详细信息，因为流体会回旋并污染燃烧器的空气供应，导致燃烧不良和火焰外观。此外，利用模拟，将生成基于严格方法的热输出、大气污染物(一氧化碳(CO)、二氧化碳(CO2)、烟尘和氮氧化物(NOx))和发光火焰的最佳运行条件图。拟议的研究将提供使用CFD的数值结果，以改进壁炉背景下的燃烧过程的设计和基本理解。拟议的工作将是为沃尔夫钢铁有限公司及其客户在竞争激烈的市场中提供进一步的尖端模拟工具的关键。

Wolf Steel Limited, parent company of Napoleon, is looking to improve existing gas fireplaces and developnew products to meet the continuously increasing consumer market demand of efficient and clean heatingproducts with an aesthetical aspect. Current design methods rely on empirical knowledge developed over manyyears for some specific burners. However, no systematic methodology based on rigorous combustion researchhas been derived that would be valid for any kind of burners and fuels. In addition to the complex chemistryinvolved in the formation of atmospheric pollutants, the desired optimal operation of gas fireplaces stronglydepends on the burner design and amount of air available for burning.The objective of the proposed research is to investigate the complex relationships between the burner geometryand operation variables and their resulting impact on heating value, flame appearance and atmosphericemissions. The proposed investigation will be conducted using Computational Fluid Dynamics (CFD) thatprovides detailed information at small turnaround times with much lower costs compared to experimentalstudies. The final results will provide detailed information on the fluid flow within the combustion chamber, asfluid can eddy back and contaminate the air supply to the burner, causing poor combustion and flameappearance. Further, using the simulations, a map of optimal operating conditions for heat output, atmosphericpollutants (carbon monoxide (CO), carbon dioxide (CO2), soot and nitric oxides (NOx)), and luminous flamesbased on a rigorous approach will be generated.The proposed research will provide numerical results using CFD to improve the design and fundamentalunderstanding of combustion processes in the context of fireplaces. The proposed work will be key towardsproviding Wolf Steel Ltd and their customers further leading-edge simulation tools in a highly competitivemarket.