Effects of the addition of ethanol and cetane number improver on the combustion and emission characteristics of a compression ignition engine

Abstract

Combustion and emission characteristics of a direct-injection diesel engine fuelled with diesel—ethanol blends were investigated. The results show that the ignition delay and the premixed combustion duration increase, while the diffusive combustion duration and the total combustion duration decrease with increase in the oxygen mass fraction in the blends. The addition of 0.2 per cent volume fraction of cetane number improver (isoamyl nitrite) could mean that the ignition delay and the premixed combustion duration of the fuel blends with 10vol% ethanol fraction recover to those of diesel fuel. Meanwhile, with the increase in the ethanol fraction in the fuel blends, the centre of the heat release curve moves closer to the top dead centre. The brake specific fuel consumption increases, while the diesel equivalent brake specific fuel consumption decreases with increase in the ethanol fraction. The exhaust smoke concentration increases and exhaust nitrogen oxide (NO x) concentration decreases on prolonging the fuel delivery advance angle for both diesel fuel and the blended fuels. For a specific fuel injection advance angle, the exhaust smoke concentration shows a large decrease and the exhaust NO x concentration a small decrease on ethanol addition.

Effect of Aluminum Oxide Nano-Particle in Jatropha Biodiesel on Performance, Emissions and Combustion Characteristics of D I Diesel Engine

“…More quantity of fuel is burnt in the premixed combustion phase [5,18,20,26,29].It was observed that heat release rate and cylinder gas pressure characteristics were higher for the alumina oxide nanoparticle blended fuels (B20+ 20 NAO, B20+ 30 NAO and B20+ 40 NAO) compared to biodiesel blend B20. This is could be due to accelerated combustion due to the shortened ignition delay, improved atomization, rapid evaporation of fuel, the degree of fuel mixing and uniform burning could have improved [11,26,37,38]. Increase in the ignition delay period had bad effects in fuel atomization and evaporation.…”

“…For different fuels, the values of peak cylinder pressure were increased with the increase of engine load due to the increase of injected fuel mass that results in increasing the amount of heat released. Higher heat release rate and cylinder pressure characteristics were observed for the nanoparticle blended test fuels B20+ 20 NAO, B20+ 30 NAO and B20+ 40 NAO compared to biodiesel blend B20 which was due to the advancement of combustion phase by improved atomization and rapid evaporation of fuel [18,26,39,40]. That cause decreased peak cylinder pressure for blended fuels compared to neat diesel fuel at all engine load range.…”

Comparative studies of a bioethanol fuelled DI diesel engine with a cetane improver

“…To overcome this issue, fuel modification is required. Nitrate-based cetane improvers such as triethylene glycol dinitrate (TEGDN), octyl nitrate, isoamyl nitrite were added to ethanol in lower quantities and investigation were carried out with the mixture effect on combustion, performance and emissions of a CI engine at different parameters and geometry by many researchers (Ren et al, 2008;Holland et al, 1992;Simonsen and Chomiak, 1995). Some of researchers reported that there was a drop in power while few have reported the similar results to that of diesel.…”

Performance and Emission Improvement of Biodiesel Fueled Diesel Engine with Exhaust Gas Recirculation and Ethyl Hexyl Nitrate Additive

“…Higher cetane numbers reduced the regulated and unregulated emissions including NO x in addition to the improvement in the engine performance [9][10][11]. Several authors [12][13][14] reported that cetane improver in combination with oxygenates improved engine performance in addition to the reduction in emissions. However, these additives are not as effective as EGR for the reduction of NO x emissions.…”