修改反应溶剂:一种简化的方法来捕获非预混合MILD火焰的分子和流量扩散率
Muddada Srinivasarao1, Bok Jik Lee2, Vanteru Mahendra Reddy1
1Mechanical Engineering Department, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India.
ACS omega
|April 15, 2024
概括
这项研究验证了对中度和强度低氧稀释 (MILD) 火焰的修改溶剂. 修改后的解决器准确地预测了火焰的行为,并大大减少了计算时间.
科学领域:
- 燃烧科学 燃烧科学
- 计算流体动力学的流体动力学.
背景情况:
- 非预混合的中度和强烈的低氧稀释 (MILD) 火焰带来了独特的燃烧挑战.
- 准确预测MILD火焰需要强大的计算模型.
研究的目的:
- 为了研究入口边界物种易斯号对MILD火焰的适用性.
- 开发和验证一种用于MILD燃烧模拟的修改反应溶剂.
- 评估解决器在预测速度,温度和火焰起飞高度方面的准确性,同时降低计算成本.
主要方法:
- 在OpenFOAM中开发了一种改性反应溶解剂,modifiedReactingFoam,通过结合流量和改性常量.
- 在MILD条件下对delft-jet-in-hot-coflow燃烧器进行了数值模拟.
- 该溶解器使用从0.9到1.14.4的甲路易斯数进行了测试.
主要成果:
- 与现有模型相比,修改后的解决器显示出更好的预测,特别是修改后的散概念.
- 使用甲的易斯数为1.12的预测显示与实验结果密切一致,起飞高度偏差在±3%内.
- 当与DLBFoam结合使用时,计算时间减少了10倍.
结论:
- 修改后的溶剂对于模拟MILD火焰是有效的.
- 入口边界物种的易斯数是准确的MILD火焰预测的关键参数.
- 开发的解决方案为MILD燃烧研究提供了一个计算效率高,准确的替代方案.
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