Why rich mixture has lower combustion efficiency?
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Rich mixtures tend to have lower combustion efficiency due to several factors. In the context of direct injection gasoline engines, locally rich mixtures or liquid fuel present during combustion lead to increased Particulate Matter (PM) emissions, impacting efficiency negatively . Additionally, in the study of partially premixed combustion, it was found that efficiency increased from rich to lean combustion, indicating that rich mixtures may not burn as completely or effectively as lean mixtures . Moreover, the hybrid rich-burn/lean-burn engine concept highlights that operating outside the combustion limits where NOx is produced, as seen in rich combustion, can lead to lower efficiency despite achieving low NOx emissions . These findings collectively suggest that rich mixtures, due to incomplete combustion and specific emission characteristics, result in lower overall combustion efficiency.
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| Papers (4) | Insight |
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14 Citations | Rich mixtures have lower combustion efficiency due to the excess fuel, leading to incomplete combustion and higher levels of CO emissions, impacting overall efficiency negatively. |
Open access•Dissertation 01 Jan 2014 | Rich mixtures have lower combustion efficiency due to pockets of unburned fuel caused by poor mixture formation, leading to higher CO emissions and reduced overall combustion effectiveness. |
| Rich mixtures have lower combustion efficiency due to interactions with lean mixtures causing phenomena like secondary flames and supported flames, affecting combustion characteristics in stratified mixtures. | |
| Rich mixtures have lower combustion efficiency due to the formation of harmful by-products, high combustion temperature, and incomplete combustion, leading to reduced overall efficiency and environmental impact. |
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