Investigation On Combustion And Emission Performance Of A Common Rail Diesel Engine Fueled With Diesel-Ethylene Glycol Dual Fuel

A turbocharged,in-line 6-cylinder,common rail diesel engine was modified to operate on diesel-ethylene glycol dual fuel?DEGDF?.Combustion and emission characteristics are investigated at 1400 r/min with four low ethylene glycol energy ratio?EGER??named D100,EG5,EG10 and EG15 respectively?.Combustion results show that peak heat release rates and pressure rise rate raise with the increase of EGER at all loads,and the peak combustion pressure increase with EGER raise in medium and high loads.EGER has little effect on the maximum temperature in the cylinder at all loads.Ignition delay is prolong with the increase of EGER in low and medium loads,but shorten with the increase of EGER in medium and high loads,and ignition delay was negative at 1.29MPa due to the auto-ignition of EG.Combustion duration decreases with the increase of EGER in low and high loads,but the increase of EGER shortens the combustion duration at medium loads.The brake thermal efficiency?BTE?are lower and the Brake specific fuel consumption?BSFC?is higher at all loads gradually followed by the rise of EGER.For gas emissions,NOx emissions is higher than that of D100 in low and medium loads,while it is opposite at medium and high loads.NO_X,THC and CO₂ emissions decrease at all loads followed by the rise of EGER,but CO emissions increase.The NO₂ proportion in NO_X is increased with the increase of EGER,especially under low and medium loads.In particular,soot emissions deteriorate significantly at low loads,and have not changed in medium and high loads.DEGDF reduce ultrafine particles?UFPs?at medium and high loads,and decrease the average diameter of UFPs.In generally,DEGDF are found to be a good choice in medium and high load such as performance and emissions.Based on the significant improvement of combustion and emission characteristics due to injection timing,the combustion and emission characteristics of ethylene glycol/diesel dual fuel engine at the time of airway injection and direct injection were studied at 1400r/min and0.81Mpa.Impact.The experimental results of the airway?ethylene glycol?injection timing show that the specific fuel consumption gradually increases with the delay of the alcohol injection angle,but changing the injection angle of the glycol does not have a significant effect on the combustion and emission characteristics of the engine.The direct injection?diesel?injection timing test results show that the peak combustion pressure and heat release rate in the cylinder increase with the injection advance angle,and the ignition timing advances significantly with the injection advance angle;the ignition delay varies.With the increase of the injection advance angle,the combustion duration is shortened;with the increase of the injection advance angle,the specific fuel consumption gradually decreases and the effective thermal efficiency gradually increases;the engine's NOX,THC,CO,soot Emissions and ultrafine particulate emissions have further improved significantly with the advance of injection timing.By analyzing the combustion and emission characteristics of the ethylene glycol/diesel dual fuel engine load test,it is found that the dual fuel engine of ethylene glycol/diesel has good working performance under high medium load and ethylene glycol has great potential in reducing diesel engine emissions.Therefore,so the ethylene glycol is a very promising diesel alternative fuel in the future.