Performance and Emissions of a Turbocharged, High-Pressure Common Rail Diesel Engine Operating on Biodiesel/Diesel Blends

Abstract

The effect of biodiesel addition to diesel on engine performance, combustion, and emissions were studied in a turbocharged, high-pressure common rail diesel engine. Biodiesel/diesel blends with different biodiesel fractions were used and compared with neat biodiesel and diesel at different engine loads and speeds. The results show that the brake thermal efficiency increases slightly as biodiesel is added to diesel. Exhaust gas temperature is not significantly affected at low engine speeds and decreases gradually at high engine speeds with an increase in biodiesel fraction. Fuel injection includes both pilot and main injections. Diesel and biodiesel give a similar start to the heat release. The first peak in the heat release rate for biodiesel is lower than that of diesel, while the second peak is higher for biodiesel. The heat release rate curve for biodiesel indicates that the use of biodiesel increases thermal efficiency and NO x emission compared to that of diesel especially at high engine loads. Hydrocarbon and CO emissions maintain very low values and little variation is seen for the different fuels. CO2 emission decreases with increasing biodiesel fraction in the blends. The level of NO x emission decreases slightly at low engine loads and increases at high engine loads with increasing biodiesel fraction. Biodiesel reduces particulate matter (PM) emission significantly and PM reduction effectiveness is increased at high engine loads and/or speed. The oxygen in biodiesel plays a key role in reducing PM emission. Biodiesel/diesel blends can improve performance and decrease emissions for turbocharged, high-pressure common rail diesel engines.

Evaluation on effects of using low biodiesel blends in a EURO 5 passenger vehicle equipped with a common-rail diesel engine

“…It was found that different oil sources for biodiesel lead to different NO x emission results, which include increase and decrease of these emissions. Wang et al [30] report improvements in combustion and energetic efficiency for B20 and B40 blends when compared with diesel (B0). It is concluded that the differences in the heat released from combustion and the lower temperature for low loads also induce a small reduction in NO x emissions.…”

Experimental Analysis of Jatropha Curcas Bio-Diesel for Optimum Blend Characteristics

“…This is considered to be an optimized blend. Fig: 9 indicate the variation of SFC with injection pressure, in which B20 providing greater result [15]. When the injection pressure is increased up to a certain level the thermal efficiency also increased.…”

Effect of Exhaust Gas Recirculation and Isobutanol Additive on Biodiesel Fuelled Diesel Engine for the Reduction of NOx Emissions

“…1-4 dioxin, as an additive in TBC engines reduces smoke density with slight increase in brake thermal efficiency and NO x with a drop in fuel economy [7]. Reduced ignition delay reduces combustion temperature which aids in reducing NO x emissions since higher combustion temperature is the primary source for NO x to increase [8]. The use of cetane improvers is an alternative way to reduce the NO x emissions which can be done by reducing ignition delay in diesel engines [9].…”