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[Evolution characteristics of diesel particles under cooling condition]
Shuang-Xi Liu1, Zhi Ning, Juan Fu
1China Automotive Technology and Research Center, Tianjin 300162, China. l_shxi2002@163.com
Huan Jing Ke Xue= Huanjing Kexue
|August 7, 2007
Summary
Cooling diesel exhaust significantly impacts particle mass concentration, primarily due to hydrocarbon condensation. This process increases particle size while reducing overall particle numbers, particularly for smaller diesel particles.
Area of Science:
- Environmental science
- Mechanical engineering
- Chemical engineering
Context:
- Diesel engine emissions are a significant source of air pollution.
- Understanding particle evolution is crucial for developing effective emission control strategies.
- Exhaust cooling is a potential factor influencing particulate matter characteristics.
Purpose:
- To investigate the evolution of diesel particles under exhaust cooling conditions.
- To determine the effects of cooling temperature and exhaust velocity on diesel particle characteristics.
- To identify the mechanisms driving changes in diesel particle mass concentration.
Summary:
- Experimental research examined diesel particle evolution under exhaust cooling.
- Cooling promotes gaseous hydrocarbon condensation, increasing particle mass concentration and size.
- Smaller particles (<0.1 microm) experience a decrease in number concentration.
- Volume concentration of particles (0.1-1.0 microm) decreases post-cooling.
- Reduced exhaust velocity leads to lower number and volume concentrations for particles (0.01-1.0 microm).
Impact:
- Provides insights into diesel particulate matter behavior under varying thermal conditions.
- Informs the design of exhaust aftertreatment systems for enhanced particulate matter control.
- Contributes to a better understanding of air quality impacts from diesel engines.
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