The Influence of Fuel Temperature on Energy, Exergy and Exhaust Emissions of a DI Diesel Engine Under Various Operating Loads

In the present article, the effects of fuel temperature on first and second law terms and exhaust emissions under the various operating loads in a DI diesel engine have been investigated. The combustion process and emissions production are simulated utilizing a three dimensional CFD code. The second law terms have been computed by a developed FORTRAN code. The calculations are carried out for three operating loads (50%, 75% and 100% load) and for each of them, five injected fuel temperatures have been mentioned: Tfuel =353, 383K as low and Tfuel =463, 493K as high temperature cases. The obtained results indicated that increasing the injected fuel temperature leads to increase in fuel spray atomization, better air-fuel mixing and improves combustion characteristics. Also, reduced spray penetration due to increased evaporation prevents wall-film formation and considerably decreases soot mass fraction. Mean pressure, temperature, and NOx mass fraction are increased due to improved combustion. Also, increasing the injected fuel temperature causes to increase the indicated work and heat loss availabilities, and decreases the exhaust gas availability and combustion irreversibilities.