Search

In this study, an alternative fuel for compression ignition (CI) engines called tri-fuel emulsion was prepared using an ultrasonic emulsifier. The objective of the study is to investigate the effect of emulsifying settings and formulation ratio on the physicochemical properties of tri-fuel emulsions. Design of experiment (DOE) with the two-level factorial design was employed to analyze the effect of emulsifying settings such as time, amplitude, and cycle along with the variation ratio of tri-fuel emulsion components as control factors. Numbers of responses identified were important parameters that may contribute to microexplosion phenomenon in CI engine. Analysis of variance (ANOVA) was carried out for each response, and the results indicated that density, dynamic viscosity, surface tension, and average droplet size were influenced by specific preparation control factors. Furthermore, interaction among the control factors was found to affect the responses as well. Interaction means the effect of two factors together is different than what would be expected from each factor separately. Besides, the stability of the tri-fuel emulsion was observed for three months. Furthermore, a qualitative approach with a multiobjective lens digital microscope revealed the geometry of freshly made dispersed tri-fuel emulsion droplets. Microscopic examination on tri-fuel emulsion droplets has shown that the dispersed ethanol capsulated within diesel with the help of biodiesel is similar to a water in diesel emulsion and is dissimilar to commercial diesel mixed with fatty acid methyl esters found in the market.

Utilization of the waste products as an alternative fuel could reduce the dependence on fossil fuel. The three types of upgraded waste source fuels discussed in this paper were tire derived fuel (TDF), waste plastic disposal fuel (WPD) and upgraded waste cooking oil (UWCO). The detailed combustion pressure showed that kinematic viscosity and cetane number played an important role in determining the combustion quality. TDF's high kinematic viscosity and low cetane number affected its fuel vaporization process; thus, lengthening its ignition delay. UWCO showed the 14% higher power and 13.8% higher torque compared to diesel fuel (DF). WPD produced the lowest NOx due to its low pressure curve during combustion. TDF had produced the highest exhaust emissions (CO, CO 2 , NO and NOx). Particulate matter (PM) emissions by UWCO blends were lower than DF. UWCO's soot concentration was 40% lower than DF and increased to 62.5% from low to high engine speed operation. [ABSTRACT FROM AUTHOR]

This research investigates the effect of nanoparticle-diesel fuel blends on combustion characteristics, performances and exhaust emissions of a four-stroke single-cylinder diesel engine. Three types of nanoparticles employed in this experiment were aluminium oxide, carbon nanotubes and silicon oxide. The nanoparticles were dispersed in a dosage of 25 ppm, 50 ppm and 100 ppm with pure diesel and were labelled as DA25, DA50, DA100 (aluminium oxide blends), DC25, DC50, DC100 (carbon nanotubes blends) and DS25, DS50, DS100 (silicon oxide blends). The ultraviolet-visible spectrophotometer analysis was done for 200 h to quantify the stability of the nanoparticle-diesel fuel blends. The blended fuels were experimentally tested with YANMAR TF120M diesel engine at engine loads of 0%, 25%, 50%, 75% and 100% at a constant 1800 rpm engine speed. The results revealed that the brake specific fuel consumption reduced by up to 19.8% and brake thermal efficiency enhanced by 18.8%. Silicon oxide blends show better results than aluminium oxide blends in many aspects, such as higher combustion pressure, lower brake specific fuel consumption and lower carbon monoxide emissions. Aluminium oxide and silicon oxide show stable blend conditions with 28.1% and 22.0% absorption ratio at 200 h sedimentation time, while carbon nanotube blends were least stable with absorption ratio reducing to less than 30% after 10 h. Combustion analysis of carbon nanotube blends with diesel show that carbon nanotubes have the potential to be further researched as an additive for diesel fuel due to significant combustion improvement in NO x emissions. However, the issue on the stability of carbon nanotube blends must be resolved before its potential can be fully utilized. [ABSTRACT FROM AUTHOR]