Influence of injection timing on performance, combustion and emission characteristics of a diesel engine running on hydrogen-diethyl ether, n-butanol and biodiesel blends

Abstract

In the present research, 5% hydrogen was added to 95%diesel fuel, diethyl ether (DEE), n-butanol (nB), and spirulina microalgae in this investigation (SMA). The fuels were then tested using a numerical tool and the Diesel RK-Model programme in a single cylinder CI engine. The results showed that the 5%H95%DEE blend consistently showed the highest level of specific fuel consumption (SFC) with increasing trend as the injection timings was advanced. In terms of brake thermal efficiency (BTE), all blends experienced decreasing trend except for 5%H95%nB. The addition of 5% hydrogen into 95% n-butanol gave relatively stable level of BTE for the entire injection timings. Furthermore, all blends witnessed relatively the same exhaust gas temperature (EGT) trend with only minor changes. Not much significance was observed from the most retarded to the most advanced injection timing. In terms of peak in-cylinder pressure, all the investigated blends saw increasing trend with the advancing injection timing. However, they experienced slight reduction at the most advanced fuel injection timing (FIT). Except for 5%H95%SMA, all blends show the highest peak in-cylinder pressure at 26.5 deg. before TDC. With regards to the ignition delay (ID), 5%H95%nB always gave the longest ID except at the 29.5 deg. before TDC, while the 5%H95%DEE consistently showed the shortest ID with nearly the same value for all Its at around 1.8–3.1 deg. Regarding the emissions, the use of n-butanol (5%H95%nB) consistently produced the lowest CO2, smoke, NOX, and particulate matter (PM) emissions throughout the entire injection timings.