中文摘要：

等离子射流点火技术在航空航天、武器工业及民用工业中均有应用。为了探索等离子射流的点火特性,对等离子射流在大气中瞬态膨胀扩展近场特性进行了数值模拟,获得了射流扩展过程中的压力、速度、温度分布以及两相界面演化特性。结果表明：等离子射流扩展过程中,射流近场逐渐形成马赫盘,并伴随射流分叉、聚合现象。正激波上游各参数均不随时间变化,下游参数随时间改变。射流前端面扩展位移计算值与实测值吻合较好。

英文摘要：

The plasma jet ignition technology has wide applications in aerospace,weapons and civilian industry.To explore the ignition properties of the plasma jet,we have conducted numerical simulation to study the characteristics of the near field of the transient plasma jet propagation in air,and have obtained the distribution properties of pressure,velocity,temperature and the evolution characteristics of the plasma-air interface.The results indicate that,as the plasma jet propagates,the Mach disk is formed gradually at the near field,and this is accompanied by the phenomenon that the plasma jet ramifies and converges.The parameters of the normal shock upstream do not vary with time,while the parameters downstream do.The calculated displacement of the front of the plasma jet matched well with the measured value.