«上一篇/Previous Article|本期目录/Table of Contents|下一篇/Next Article»

《内燃机学报》[ISSN:1006-6977/CN:61-1281/TN]

卷:

期数:

2023年01

页码:

1-8

栏目:

出版日期:

2023-01-25

文章信息/Info

Title:

Chemical Kinetics Study of the Autoignition of NH3/CH4 Mixtures

作者:

徐昊; 何志霞; 戴礼明; 王谦

1. 江苏大学 能源与动力工程学院，江苏 镇江 212013；2. 江苏大学 能源研究院，江苏 镇江 212013

Author(s):

Xu Hao; He Zhixia; Dai Liming; Wang Qian

1. School of Energy and Power Engineering，Jiangsu University，Zhenjiang 212013，China； 2. Institute for Energy Research，Jiangsu University，Zhenjiang 212013，China

关键词:

氨气与甲烷混合气; 化学动力学; 着火延迟时间; 快速压缩机

Keywords:

ammonia/methane mixtures; chemical kinetics; ignition delay time; rapid compression machine

分类号:

TK438.9

文献标志码:

A

摘要:

在当量比φ＝0.5、压力为2～7MPa 以及温度从930 K 到1 140 K 的条件下，用快速压缩机研究氨气(NH3) 和甲烷(CH4)混合气的着火延迟时间，其中CH4 占总燃料的摩尔分数分别为0、5%、10%及50%．另外，在φ为 1.0 和2.0 的条件下对掺入10% CH4的混合气进行着火延迟时间测试．CH4对NH3的着火过程具有非常明显的促进 作用，随着CH4 占总燃料的比例越来越高，混合气的着火延迟时间缩短，同时CH4 对着火的促进作用趋于平 缓．含10% CH4的NH3的着火延迟时间在φ为0.5 和1.0 的条件下变化很小，而当φ＝2.0 时着火延迟时间增加约 50%．利用试验数据对6 种不同的NH3氧化机理进行了验证，所开发的机理预测着火延迟时间最为准确，除了在 最高温度，CH4摩尔分数为50%时试验与计算差异达到了50%，其他所有条件下机理的预测结果与试验结果差距 都小于30%．利用开发的机理进行敏感性分析，结果表明：当CH4摩尔分数为5%和10%时，反应CH4＋NH2＝ CH3＋NH3对稀薄燃烧条件下混合气的着火延迟时间有显著的促进作用；但当CH4摩尔分数为50%时，该反应会 表现出轻微的抑制作用．

Abstract:

Ignition delay times of NH3/CH4 mixtures with CH4 mole fractions of 0，5%，10% and 50% were measured in a rapid compression machine at equivalence ratio of 0.5，pressures from 2—7MPa and temperatures from 930 K to 1 140 K. In addition，measurements were performed for NH3 mixtures with 10% CH4 at φ＝1.0 and 2.0. Methane shows a strong ignition-enhancing effect on NH3，which levels off at higher CH4 fractions，as the ignition delay time approaches that of pure methane. Autoignition delay times at 10% CH4 at φ＝0.5 and 1.0 are indistinguishable， while an increase of ignition delay times by factor of 1.5 was observed upon increasing φ to 2.0. The experimental data were used to evaluate six NH3 oxidation mechanisms capable of simulating NH3/CH4 mixtures. The mechanism previously used shows the best performance：generally，it predicts the measured ignition delay times to better than 30% for all conditions，except for 50% CH4 addition for which the differences increase up to 50% at the highest temperature. Sensitivity analysis based on the mechanism used indicates that under lean conditions the reaction CH4＋NH2＝CH3＋NH3 significantly promotes ignition for modest CH4 addition(5% and 10%)，but becomes modestly ignition-inhibiting at 50% CH4

常用功能

更新日期/Last Update: 2023-01-25