Currently, using biofuels to operate diesel engines gets a
great attention to the extent that it could replace the limited
conventional fossil fuels. These fuels have a closed life
cycle (renewable) and they have a remarkable effect on
the global greenhouse phenomena. Moreover, the use of
non-edible vegetable oils is considered a good choice after
a suitable chemical and/or thermal treatment to convert
them into esters. The use of jojoba oil shows a promising
alternative fuel for conventional diesel fuel even there
were unfavorable effects including power reduction. The
wide spread usage of nano additives to improve the
combustion quality may be a good solution for these
problems. This study represents an experimental
investigation to examine the effect of nano additives on
diesel engine performance at variable operating conditions
of load and speed. In this work, alumina nano-particles are
added to a mixture of jojoba methyl ester (biodiesel) and
conventional diesel fuel at the most recommended value
(20% biodiesel and 80% diesel fuel) with different doses
from 10 up to 50 mg/l. The received mixture is
homogenized with an ultrasonicator mixer. It is found that,
the appropriate nano-additives dose corresponding to
optimal engine performance is about 30 mg/l. At this dose,
the overall BSFC is reduced by about 6%, engine thermal
efficiency is increased up to 7%, and all engine emissions
have been reduced (NOx about 70%, CO about 75 %,
smoke opacity about 5%, and UHC about 55 %) compared
with the corresponding values obtained when only a
blended fuel of 20% biodiesel is used. |
