nozzlendn.喷嘴根部nozzlen.喷嘴nozzle combination form喷头组合型式nozzleless rocket motor无喷管火箭发动机nozzle-mix gas burner喷射式混合气体燃烧器nozzle outlet gas angle喷嘴出气角nozzle area coefficient喷嘴面积系数nozzle actuating sleeve喷口致动套筒nozzle tube lever block嘴管杆垫块nozzle divergence angle喷嘴扩张角nozzle passage friction喷嘴通道摩擦nozzle-valve assembly喷油嘴组件