Classification of Volatile Engine Particles

Abstract

Volatile particles cannot be detected at the engine exhaust by an aerosol detector, as they are formed when the exhaust is mixed downstream with the ambient air. The lack of a precise definition of volatile engine particles has been an impediment to engine manufacturers and regulatory agencies involved in the development of effective control strategies. Volatile particles from combustion sources contribute to the atmospheric particulate burden, and this is a critical issue in ongoing research in the areas of air quality and climate change. A new instrument, called a volatile particle separator (VPS), is developed in this work. It utilizes a proprietary microporous metallic membrane to separate particles from vapors. VPS data are used in the development of a two-parameter function to quantitatively classify, for the first time, the volatilization behavior of engine particles. The value of parameter "A" describes the volatilization potential of an aerosol. A nonvolatile particle has a larger A-value than a volatile one. The value of parameter "k," an effective evaporation energy barrier, is found to be much smaller for small engine particles than for large engine ones. The VPS instrument is not simply a volatile particle remover, as it makes possible the characterization of volatile engine particles in numerical terms.

Application of HCCI Engine in Motorcycle for Emission Reduction and Energy Saving

“…Exhaust emissions of internal combustion engines are significant sources of air pollution (Yao and Tsai, 2013;Cheng, 2013). They not only create potential global warming effects, but also are implicated in human health issues.…”

Experimental Study on HCCI Combustion in a Small Engine with Various Fuels and EGR

“…The exhaust emissions of internal combustion engines are major sources of air pollution (Cheng, 2013;Yao and Tsai, 2013), which deteriorates human health and causes the global warming effect. Therefore, numerous technologies regarding engine combustion, after treatments, and fuels have been studied.…”

Investigation of Artificially Generated and Ambient Carbonaceous Particulate Matter

“…Both processes take place until the thermally driven equilibrium state is reached at a given temperature. These phenomena can modify the chemical composition and the mixing state of the freshly emitted diesel particulates, thus the climatic and human health impacts of diesel emitted particulate matter (Cheng, 2013).…”

“…The mixing state (the ratio of non-volatile elemental carbon to volatile carbonaceous particulate matter) of diesel emitted carbonaceous particulate matter (DPM) has significant effect on their climatic and human health too (Bond et al, 2013;Pöschl, 2003;Cheng, 2013). Since DPM is always in thermal equilibrium with its gas ambient at local temperature (even in a dynamically changed reactive and turbulent exhaust atmosphere), ensuring proper sampling and measurement conditions to investigate the mixing state of DPM is deemed essential to study the versatile impact of that.…”

“…This curious behaviour is not consistent with most of the existing data in the literature. However, since, the operating condition of the diesel engine is not optimized for high FAME content and since legal regulation restricts maximum FAME content of diesel fuels below 10%, the available studies focus mainly on intercomparing diesel fuel with pure FAME or with limited FAME content (Abdul-Khalek et al,1999;Burtscher, 2005;Lloyd and Cackette, 2001;Cheng, 2013). Detailed analysis of biodiesel blends with high mixing ratio is rather limited in literature.…”