Particle number size distribution from direct-injection premixed combustion engine fueled with gasoline/diesel blends

Abstract

The organizing of combustion process in the advanced internal combustion engine is developing toward unified combustion mode of gasoline-engine-like premixed gas formation and diesel-engine-like compression ignition. Gasoline/diesel blended fuel has received extensive attention for its suitability for this combustion characteristic, owing to its relatively poor ignitability and high volatility. In order to more comprehensively evaluate the application of the blended fuel on this combustion mode, an experiment was conducted to characterize the particle size distribution and total number concentration of exhaust particles from the gasoline/diesel blended fuel. The premixed combustion characteristics and relatively high hydrocarbon emission were confirmed first and their effects on the particle size distribution were determined subsequently. Combustion control parameters such as exhaust gas recirculation and injection pressure were also taken into account. Results indicated that gasoline/diesel blended fuel had significant effect on the particle size distribution due to the higher premixed combustion ratio and more unburned hydrocarbon emission. Under high load condition, as the proportion of gasoline blending increased, the accumulation mode particle decreased while the nucleation mode particle and total particle number increased significantly. The geometric mean diameter of exhaust particle decreased with the addition of gasoline. The effect of exhaust gas recirculation and injection pressure on the particle size distribution of gasoline/diesel blended fuel was less than that of pure diesel. That meant the gasoline/diesel blends were beneficial for carbonaceous particle (>22 nm) reduction. However, the nucleation mode as well as total particle number were still higher for gasoline/diesel blends than that for pure diesel.

Study of Particle Size Measurement by the Extinction Method in Flame

“…In some applications, it was not the particle size distribution that was of interest but rather the mean particle size. The mean particle size parameters D [4,3] and D [3,2] of these particle size distributions and the Malvern measurements are compared in Table 2. For the higher-order mean particle sizes, the LEM particle size measurement results converged with those of the Malvern laser particle size analyzer.…”

“…In industrial processes, many combustion processes include particle combustion, and the factors affecting the combustion efficiency are not only related to the characteristics of the fuel itself but also to the flow state and size of the particles. For example, the combustion of fuel in an internal combustion engine is the combustion of fuel particles after atomization, and the size of the fuel particles after atomization affects the combustion efficiency and exhaust emissions [1][2][3]. For instance, coal combustion in a boiler is the combustion process of pulverized coal in the form of granules, and the morphology and kinematic state of the particles change dramatically during the combustion process, while the morphology, size and kinematic parameters of the fuel particles have a significant impact on the performance of the burner [4,5].…”

Effects of Intake Components on Combustion and Emission Characteristics in an n-Butanol/Diesel Blend Fueled Engine

“…In addition, the mass of AMP decreases continuously with an increase in the oxygen concentration, but the change in NMP mass with the oxygen concentration shows different trends at different EGR rates and fuels. This is because AMP is mainly formed in the local hypoxic zone due to the uneven distribution of oxygen concentration during the diffusion combustion process. , Introducing oxygen into the intake is conducive to improving the in-cylinder oxygen concentration distribution, reducing the local hypoxic zone, thereby suppressing the formation of AMP. For NMP, although increasing the in-cylinder oxygen concentration is beneficial to reducing the unburned HC and thus suppressing the generation of nuclear particles, but at the same time, oxygen addition reduces the mass concentration of AMP, so it stunts the adsorption of gaseous precursors such as sulfuric acid and HC on the surface of AMP, thus increasing the NMP emission.…”

The effects of E80D20 ethanol-diesel blend on combustion and exhaust emissions in SI engine

“…Using diesel in SI mode caused higher knocking than gasoline but better results were obtained in terms of performance with diesel fuel at low EAR. Wang et al [10] aimed to characterize the change in PN size by examining the combustion of diesel/gasoline mixture in premixed and compression ignition mode. As the gasoline ratio in the mixture increased, the total particle number increased, but the particle size decreased.…”