Experimental investigation on diesel engine with diestrol–water micro emulsions

Experiments were conducted on a single cylinder direct injection diesel engine using diesel, biodiesel and biodiesel–diesel–ethanol (diestrol) water micro emulsion fuels to investigate the performance, emission and combustion characteristics of the engine under different load conditions at a constant speed of 1500 rpm. The results indicated that biodiesel and micro emulsion fuels had a higher brake specific fuel consumption (BSFC) than that of diesel. A slight improvement in the brake specific energy consumption (BSEC) was observed for micro emulsion fuels. The brake thermal efficiency of biodiesel and micro emulsion fuels were comparable to that of diesel. The emission characteristics like carbon monoxide (CO), carbon dioxide (CO2), unburnt hydrocarbon (UHC), nitric oxide (NO) and smoke emissions for biodiesel and micro emulsion fuels were lower than diesel fuel at all load conditions. The cylinder gas pressure of micro emulsion fuels was lower than diesel at low loads but it became almost identical to diesel at medium and full load conditions. The heat release rate for micro emulsion fuels was higher than biodiesel and diesel fuels for all loads. Biodiesel showed shorter ignition delay for the entire load range and the longer ignition delay observed for micro emulsion fuels.

Research highlights
► Diesel engine was investigated using diestrol–water micro emulsion fuels.
► The chosen fuels showed identical brake thermal efficiency as that of diesel fuel.
► Lower emission characteristics were achieved using micro emulsified fuels.
► Test fuels yielded higher cylinder pressure and heat release rate at full load.
► Diestrol–water micro emulsion fuels can be used as an alternative to diesel.