乙醇掺混燃烧对柴油机油耗影响的实验研究

乙醇吸热后部分热解可产生多种气体的混合物,为了研究气体混合物掺混燃烧在柴油机上的节油效果,对柴油机系统进行了改造:乙醇通过安装在柴油机排气管上的小型高效换热器吸收烟气余热,部分热解后混合气体由进气道通入柴油机燃烧室改善燃烧.在该系统上进行了定功率-不同转速以及额定转速-不同功率下的节油试验,表明:该系统在高低功率条件下均有较好的节油和节能效果.柴油机转速为1 500 r/min时,节油率最高可达40％,节能率最高可达13.5％；在柴油机额定转速2 000 r/min时,节油率最高可达24％,节能率最高可达5.7％.结合乙醇热解的气体混合物的测量数据,得出了低功率下主要依靠乙醇蒸气,高功率下主要依靠小分子气体的节油原理.

Experimental Study of the Influence of Ethanol Mixed and Diluted Combustion on the Oil Consumption of a Diesel

After a heat absorption,ethanol can be pyrolyzed partially and produce a mixture of several gases.To study the oil saving effectiveness of gas mixing and dilution combustion in a diesel engine,the diesel system was modified:let ethanol to absorb the waste heat of the exhaust gas by passing through a miniature and efficient heat exchanger mounted on the exhaust gas pipe of the diesel engine and after a pyrolysis in a part,the gas mixture thus produced is fed into the combustor of the diesel engine via an inlet pipe to improve the combustion.On the system under discussion,an oil-saving experimental study was conducted at constant power-various rotating speeds and rated speed-various powers.The research results show that the system in question can have a relatively good oil-saving and energy-saving effectiveness at both high and low powers.When operating at 1500 r/min.the diesel engine can achieve a possible highest oil-saving rate and energy-saving rate of 40% and 13.5% respectively.When operating at 2000 r/min,the diesel can attain a possible highest oil-saving rate and energy-saving rate of 24% and 5.7% respectively.The measurement data of the gas mixture pyrolyzed from ethanol induce one to conclude that the oil-saving principle of the system mainly depends on ethanol steam at a low power while mainly on gases with small molecules at a high power.