en |
Performance analysis of Diesel engines fueled by biodiesel blends via thermodynamic simulation of an air-standard Diesel cycle
Jeshvaghani, H. Shahmirzae; Fallahipanah, M.; Gahruei, M. Hashemi & Chen, L.
Abstract
Because of environmental problems, it
becomes necessary to develop alternative fuels that give
engine performance at par with diesel. Among the alternative
fuels, biodiesel and its blends hold good promises as
an eco-friendly and the most promising alternative fuel for
Diesel engine. The properties of biodiesel and its blends
are found similar to that of diesel. Many researchers have
experimentally evaluated the performance characteristics
of conventional Diesel engines fueled by biodiesel and its
blends. However, experiments require enormous effort,
money and time. Hence, via finite-time thermodynamics
simulation, an air-standard Diesel cycle model with heat
transfer loss and variable specific heats of working fluid is
analyzed to predict the performance of Diesel engine. The
effect of compression ratio, cut-off ratio and fuel type on
output work and thermal efficiency is investigated through
the model. The fuels considered for the analysis are conventional
diesel, rapeseed oil biodiesel and its blend
(20 % biodiesel and 80 % diesel by volume). Numerical
simulations showed that the output work and thermal
efficiency of the engine decrease with increase of cut-off
ratio for all fuels. Also, the model predicts similar performance
with diesel and biodiesel blend which means that
the biodiesel blend (20 % biodiesel and 80 % diesel by
volume) could be a good alternative and eco-friendly fuel
for conventional Diesel engines without any need to
modify the engine.
Keywords
Finite-time thermodynamics; Irreversible Diesel cycle; Numerical simulation; Output work; Rapeseed oil; Thermal efficiency
|