Scholarlink

<p>To meet the stringent emission and fuel consumption regulations, lean-burn technology is a key direction for improving energy efficiency and reducing fuel consumption in gasoline engines. However, traditional three-way catalysts (TWC) are unable to effectively remove nitrogen oxides (NO<sub>x</sub>) under lean-burn conditions. The NO<sub>x</sub> storage reduction (NSR) catalyst can achieve NO<sub>x</sub> removal, but it requires frequent switching between lean and rich combustion modes, making the control complex. This study proposes a TWC + NSR coupling technology route. Based on the reaction mechanism reported in the literature, by injecting low-frequency hydrocarbons upstream of the NSR, it is speculated that reducing species such as –CN and –NCO can be generated, thereby achieving the continuous reduction of NO<sub>x</sub> under lean combustion conditions. A GT-POWER model was established to simulate exhaust data, which was verified by experimental results in the literature (error ≤ 10%), providing support for subsequent experiments. Small-scale tests showed that the TWC can efficiently purify HC/CO, but has no effect on NO<sub>x</sub> removal; through a self-developed injection control system and Horiba analyzer, a test bench experiment was conducted to verify the feasibility of this coupling route, and the optimal injection parameters were determined as a frequency of 0.25&#xa0;Hz, a pressure of 4–6&#xa0;bar, within the exhaust temperature range of 350–550&#xa0;°C, an air–fuel ratio of λ = 1.2–1.6, and a rotational speed of 1500–2500&#xa0;rpm. Under these conditions, the NO<sub>x</sub> conversion rate can reach over 85%, and the additional fuel consumption can be controlled within 1%. At the same time, the influence laws of air–fuel ratio, rotational speed, and load on NO<sub>x</sub> removal effect were clarified, providing a reference for the engineering application of this technology.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Research on low-frequency hydrocarbon injection control strategy and NOx removal performance of TWC + NSR coupling system for lean burn gasoline engines

  • 期刊论文

  • 发表日期：

    2026年4月20日

查看全文
  • Bin Guan,
  • Zhongqi Zhuang,
  • Lei Zhu,
  • Tiankui Zhu,
  • Luoxin Xu,
  • Xuehan Hu,
  • Chenyu Zhu,
  • Sikai Zhao,
  • Junyan Chen,
  • Junjie Gao,
  • Kaiyou Shu,
  • Hongtao Dang,
  • Luyang Zhang,
  • Yuan Li,
  • Wenbo Zeng,
  • Shuai Chen,
  • Linhui Wang,
  • Can Zhu,
  • Jiaming He,
  • Qinghan Xian,
  • Zhen Huang

摘要

To meet the stringent emission and fuel consumption regulations, lean-burn technology is a key direction for improving energy efficiency and reducing fuel consumption in gasoline engines. However, traditional three-way catalysts (TWC) are unable to effectively remove nitrogen oxides (NOx) under lean-burn conditions. The NOx storage reduction (NSR) catalyst can achieve NOx removal, but it requires frequent switching between lean and rich combustion modes, making the control complex. This study proposes a TWC + NSR coupling technology route. Based on the reaction mechanism reported in the literature, by injecting low-frequency hydrocarbons upstream of the NSR, it is speculated that reducing species such as –CN and –NCO can be generated, thereby achieving the continuous reduction of NOx under lean combustion conditions. A GT-POWER model was established to simulate exhaust data, which was verified by experimental results in the literature (error ≤ 10%), providing support for subsequent experiments. Small-scale tests showed that the TWC can efficiently purify HC/CO, but has no effect on NOx removal; through a self-developed injection control system and Horiba analyzer, a test bench experiment was conducted to verify the feasibility of this coupling route, and the optimal injection parameters were determined as a frequency of 0.25 Hz, a pressure of 4–6 bar, within the exhaust temperature range of 350–550 °C, an air–fuel ratio of λ = 1.2–1.6, and a rotational speed of 1500–2500 rpm. Under these conditions, the NOx conversion rate can reach over 85%, and the additional fuel consumption can be controlled within 1%. At the same time, the influence laws of air–fuel ratio, rotational speed, and load on NOx removal effect were clarified, providing a reference for the engineering application of this technology.