01-06-2012, 02:10 PM
Performance of Single Cylinder DI Diesel Engine –Varied Compression Ratio Fueled With Blends of Ethanol
Performance of Single Cylinder DI Diesel Engine.pdf (Size: 882.03 KB / Downloads: 851)
INTRODUCTION
Increase in petroleum prices, threat of global warming has
generated an interest in developing alternative fuels for
engine. Technologies now focusing on development of plant
based fuels, plant oils, plant fats as an alternative fuel.
Biodiesel is described as fuel comprised of mono-alkyl
esters of long chain fatty acids derived from vegetable oils
or animal fats. Biodiesel and ethanol can be produced from
feedstock’s that are generally considered to be renewable.
Since the carbon in the biodiesel originated mostly from
CO2 in the air, the full cycle CO2 emissions for biodiesel
contribute much less to global warming than fossil fuels.
Although biodiesel cannot entirely replace petroleum- based
fuels, bio-fuels and diesel fuel blends can be used on
existing engines to achieve both environmental and energy
benefits. Ethanol is a low cost oxygenate with high oxygen
content (35%) that has been used in ethanol–diesel fuel
blends.
MATERIALS & EXPERIMENTAL SETUP
Commercial diesel fuel used in India which was obtained
locally is used as a base line fuel for this study. Ethanol used
in this study is anhydrous ethanol (99.7%) purity. The
important chemical and physical properties of blends were
determined by standard methods and compared with diesel.
The analytical results are shown in Table II. Fuel and its
blends density and heating value were measured in a
laboratory with hydrometer and bomb-calorimeter.
Properties of test fuels were reported in Table-II.
RESULTS AND DISCUSSION
A. Fuel Consumption
compares the specific fuel consumption of diesel
and various blends of ethanol at varying brake loads and
compression ratio. It was observed that the fuel consumption
(kg/hr) at maximum load of 8 kg for blends of 5%, 10%,
15% & 20% were 0.638, 0.696, 0.670, 0.658 respectively
for compression ratio of 25.10. However for the
compression ratio of 24.78 it is observed as 0.672, 0.737,
0.708, 0.750 respectively for the blends and for
Compression ratio 24.48 it was 0.784, 0.767, 0.736, and
0.798. For pure diesel it was observed as 0.617, 0.627 and
0.617 for a compression ratio of 25.10, 24.78 and 24.48
respectively. For the same maximum load on the engine fuel
consumption was minimum for pure diesel compared with
blends of ethanol.
CONCLUSION
For all fuel sample tested it is observed that with the loading
of the engine at 2.138 kW (@57 %) BTE of pure diesel and
blend of diesel and ethanol was almost same. That of
kerosene BTE was low compare with diesel and ethanol
blend. For 20 % mixture of ethanol blend with diesel has a
very good efficiency compared with pure diesel and blend of
kerosene. Also it is observed that the 20 % ethanol blend is
having higher volumetric efficiency compare with diesel and
kerosene blend. Exhaust gas temperature for ethanol blend
has not shown any substantial increase compare with pure
diesel. Hence blending of ethanol at about 20 % can lead to
a better performance of engine compare with pure diesel.