CAJ | 학술논문

搭建汽油机数值模型，按照汽油机燃烧效率随空燃比增大而升高、缓慢下降及大幅下降等现象，将空燃比划分为3个阶段，分析了不同阶段内工质绝热指数、压缩比、燃烧持续时间及传热损失对指示效率的影响规律。结果表明，随空燃比升高，绝热指数对指示效率的影响变小，提高压缩比使得末端气体温度升高，加长燃烧持续时间，导致热量转化为功的能力下降。综合分析可知，在第2阶段实现汽油机稀燃其指示效率增幅较大。
탑건기유궤수치모형，안조기유궤연소효솔수공연비증대이승고、완만하강급대폭하강등현상，장공연비화분위3개계단，분석료불동계단내공질절열지수、압축비、연소지속시간급전열손실대지시효솔적영향규률。결과표명，수공연비승고，절열지수대지시효솔적영향변소，제고압축비사득말단기체온도승고，가장연소지속시간，도치열량전화위공적능력하강。종합분석가지，재제2계단실현기유궤희연기지시효솔증폭교대。
In this paper,the simulation model of the engine was established and the AFR(air fuel ratio) was divided into 3 phases,in which the gasoline engine combustion efficiency presents different trends with the increaseof AFR,namely increase,slow decrease,and sharp decrease. The influence of adiabatic exponent,compress ratio, combustion duration and heat transfer on the indicated efficiency of engine was analyzed. The result shows that with the increase of AFR,the influence of adiabatic exponent on the indicated efficiency becomes smaller,that with in-crease of the temperature of the gas,and the combustion duration,the growth of irreversibility declines. Applying the lean burn technology in the second phase can guarantee the best efficiency benefits.