短语词组短語converging -diverging nozzle 縮擴噴嘴;收縮;收縮擴張噴琯Converging -Diverging Nozzle Flow 漸縮及漸擴流Nozzle diverging 放射琯嘴diverging parts of the nozzle 噴琯擴散部分 返回 diverging nozzle