Page 289 - Biosystems Engineering

266 Cha pte r Ei g h t

14
Diesel
12 Putranjiva oil
Karanja oil
10 Jatropha oil

Smoke (Hu) 8

6

4

2

0
0.0 0.5 1.0 1.5 2.0 2.5 3.0
Brake power (kW)
FIGURE 8.7 Smoke versus brake power of diesel fuel, 100 percent biodiesel
of Jatropha, karanja, and putranjiva at 1200 rpm, 45° angle bTDC, and
20 compression ratios.

alternative fuel for diesel engines. Out of the three oils, Jatropha
promises to yield good performance and lower emissions at each
load in all respects. Considering the above-mentioned points, we can
conclude that a diesel engine can run very satisfactorily using 100
percent fatty acid methyl ester (pure biodiesel) at 45° angle bTDC
timing, and a compression ratio of 20. Any diesel engine can be
operated with 100 percent biodiesel as a prime mover without any
modifications to the engine.

8.2 Ethanol as an Alternative Fuel
Ethanol as an alternative liquid fuel has recently attracted consider-
able attention, particularly from the agricultural sector. However,
farmers are limited in their ability to use ethanol because most field
equipment today are equipped with diesel engines and fuel would be
most critically needed for field operations during a shortage. Ethanol
may be used to replace, supplement, or extend the use of diesel fuel.
The use of alcohol in spark–ignition engines (SI) started in 1954 in
countries like the United States, Germany, and France. During World
Wars I and II when a gasoline shortage occurred in France and Germany,
alcohol was used in all types of vehicles including military planes.