expansion stroke meaning in Chinese

膨胀冲程
膨胀衡程
膨胀行程

In this paper , the general theory and numerical solution procedure were described . by building a diesel modeling with vertical valves and a piston bowl , a whole cycle was calculated , which include intake stroke , compression stroke , expansion stroke and exhaust stroke
通过对带有进、排气门的柴油机进行计算，模拟了一个完整循环内进气道、气门和缸内气体流动的全过程。