抄録
High concentration of nitrogen oxide is detected in the exhaust gas during the cranking process of internal combustion engines. In this paper, the mathematical model which estimates the generation of nitrogen oxide in the cranking process is developed. The highest NO concentration in the first cycle is found by the calculated results. This fact can be explained by no residual gas and lowest rotational speed in the first cycle. The effect of the rotational speed on NO concentration is measured and confirmed by the calculated results.