等离子体射流产生与特性的实验研究

本文报道热等离子体射流产生及射流特性的实验研究结果。采用同一个直流等离子体发生器,工作气体流量小时产生出层流等离子体长射流,射流长度随气体流量或弧电流的增加而明显增加;工作气体流量大时则产生出湍流等离子体短射流,此时射流长度几乎与工作气体流量或弧电流无关;在层流与湍流等离子体射流工况之间,存在一个流动状况不稳定的过渡区,此时等离子体射流的平均长度随气流量的加大而减小,但随弧电流的加大而明显加大。层流等离子体长射流有相当好的刚性。

EXPERIMENTAL STUDY ON THE GENERATION AND CHARACTERISTICS OF PLASMA JETS

Experimental results of the generation and characteristics of plasma jets have been presented in this paper. By using the same DC arc plasma generator, long laminar plasma jets are generated with lower working-gas flow rates and the laminar jet length increases apparently with increasing working-gas flow rate or arc current; while short turbulent plasma jets are generated with higher working-gas flow rates and the turbulent jet length is almost independent of the working-gas flow rate or arc current. Between the laminar and turbulent jet regimes, there exists an unstable transient regime, in which the mean jet length decreases with increasing gas flow rate but increases with increasing arc current. The long laminar plasma jet has good stiffness.