摘要
空燃比对发动机运行状况和排放特性具有重要意义,由发动机排气成分计算空燃比的方法被广泛应用。本文根据Spindt法和全气法,结合汽油机的燃烧特点,推导出更简便的空燃比计算方法 -碳原子平衡法。以18个工况点的直采排放数据为例,对比分析三种方法的计算值。结果表示,与宽氧传感器的测量值相比,Spindt法计算值的误差范围为1.5%～2.5%,全气法和碳原子平衡法相差甚微,碳原子平衡法具有广泛的适用性。由于各种排放标准制定的环境和条件不同,本文对比了SAE J1088、GB17691、ISO8178三种标准中关于气态污染物比排放量的计算公式,根据当前进行发动机试验的实际条件,以一组汽油机台架试验的直采测量结果为例,基于空燃比的计算提出了更合适的比排放量计算公式。
Air-fuel ratio has great significance on operating conditions and emission characteristics of the en- gine. The method to calculate air-fuel ratio through exhaust components has been widely used. Combined with the combustion characteristics of gasoline engine, the carbon balance method was deduced according to the principle of combustion, which is simpler than the Spindt and full gas methods. The calculated results of three methods on emissions data of 18 operating points were compared and analyzed. The results show that the cal- culated value of Spindt-law has difference from 1.5 % to 2.5 %, full gas law and the carbon balance method differ little, compared with the measured value of a Bosch UEGO （ Universal Exhaust Gas Oxygen） sensor. So carbon balance method has broad applicability. Meanwhile different environment and conditions of various e- missions standards, the calculation formula on emission value of gaseous pollutants in standards SAE J1088, GB1791 and ISO8178 were compared. According to our conditions of engine test, more suitable calculation formula was selected based on the calculation of the air-fuel ratio.
出处
《小型内燃机与摩托车》
CAS
2013年第3期56-61,共6页
Small Internal Combustion Engine and Motorcycle
关键词
汽油发动机
台架试验
空燃比
气体排放
Gasoline engine, Bench test, Air-fuel ratio, Gaseous emissions
