通过气门与气门座接触动应力的光弹试验,得出与静态应力很不相同的结果,从而揭示出气门破坏的原因,亦说明了气门接触面与过渡圆弧对气门应力集中的关系. Through the photoelastic test that the valve and the valve seat are in contact with the dynamic stress, the result is very different from the static stress, so as to reveal the reason of the valve damage and also explain the relationship between the valve contact surface and the transitional arc on the valve stress concentration.