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Reducing carbon dioxide (greenhouse gas) is one of the most important drivers to promote biofuels. Fuel from biomass has the potential to reduce greenhouse gas emissions and can gradually reduce the dependence on fossil fuels. However, fuel properties can differ significantly from standard diesel fuel and this will affect exhaust emissions and environmental pollution. Diesel – ethanol fuel blends development and specification are currently driven by the engine technology, existing fossil fuel specification and availability of feedstock. Thus, the aims of this study to investigate the effects of fuel additives with diesel–ethanol fuel blend under steady-state conditions. In the present study, the additives were palm diesel, n-butanol, ethyl acetate and di-tert-butyl peroxide (DTBP). The ratio of conventional diesel fuel to ethanol fuel to fuel additive are 80:15:5 by volume of fuel blends.

The aims of this research is investigate the hydrogen production via biodiesel fuel partial oxidation reforming. Hydrogen production can enhance combustion in cylinder and improved aftertreatment activities. A reforming reaction is when a chemical reacts with oxygen available in exhaust gas and diesel fuel injection. The 2%Pt-1%Rh-CeO2-ZrO2/γ-Al2O3 was selected as the active catalyst in this research. This study investigates the effect of gas space velocity (SV) (e.g., 10k h-1 and 16k h-1) and fuel addition flow rate (10-30 ml/h) on hydrogen production efficiency. As can be seen that the hydrogen from reforming reaction was promoted under the real engine operating conditions. Hydrogen is produced via partial oxidation of hydrocarbons reforming. The effects of space velocity SV (h−1) and hydrocarbon addition, which enhanced energy input for the reforming process, are the main effect on hydrogen production over the reforming catalyst. The maximum hydrogen yield are achieved 11%.

The main aim of this work is to characterize the combustion phenomena and particulate matter in nano-size from the reactivity controlled compression ignition (RCCI) engine using neat hydrous ethanol as a low reactivity fuel. A four-cylinder diesel engine fueled with diesel (the volumetric blend of 95% petroleum diesel and 5% palm-based biodiesel) was operated on low and medium loads at 2,500 rpm without main diesel fuel injection modification and exhaust gas recirculation. Ethanol was injected at 1 bar pressure into the intake manifold while the w/w ratios of ethanol:diesel were varied between 0 and 0.77. An engine indicating system composed of an in-cylinder pressure transducer and a shaft encoder was used to investigate combustion characteristics using the first law of thermodynamics. A Scanning Mobility Particle Sizer and an Optical Particle Sizer were used to determine the particle number concentration and distribution over nano-size range.

Computational Fluid Dynamics (CFD) is used to simulate chemical reactions and transport phenomena occurring in a single channel of a honeycomb-type automotive catalytic converter under lean burn combustion. Microkinetic analysis is adopted to develop a detailed elementary reaction mechanism for propane oxidation on a silver catalyst. Activation energies are calculated based on the theory of the Unity Bond Index-Quadratic Exponential Potential (UBI-QEP) method. The order-of-magnitude of the pre-exponential factors is obtained from Transition State Theory (TST). Sensitivity analysis is applied to identify the important elementary steps and refine the pre-exponential factors of these reactions. These pre-exponential factors depend on inlet temperatures and propane concentration; therefore optimised pre-exponential factors are written in polynomial forms. The results of numerical simulations are validated by comparison with experimental data.