电弧等离子体射流核脉动的实验研究

电弧等离子体射流中的湍流是等离子体射流的典型物理现象之一，而以往的研究认为射流存在一个处于稳定状态的核心区域，也有人认为这个状态是层流的。本文采用电弧等离子光谱诊断及数字高速摄影的方法对常压电弧等离子体射流核进行了研究，采用了傅里叶变换的方法分析弧电压和射流光谱强度信号，发现电源的交流分量和阳极弧点运动对整个射流核的脉动特性都有体现，射流并不存在一个处于稳定状态的核心区域，相反谱线强度脉动图中可以看到，射流核的脉动是由电弧电压脉动造成的，这可能是射流核脉动的最主要原因。

Study on the Fluctuation Phenomena of Arc Plasma Spraying Jet

The turbulence phenomenon is one of the most attractive characteristics of a DC arc plasma spraying jet. Most of the previous investigations believe that there is a laminar flow region in core of the jet.A spectrum diagnostic system has been built up in this paper to investigate these effects with the aid of high speed digital camera. The FFT method has been applied to the analysis on the arc voltage and light signals. The influence of the arc behavior and the power supply on the jet is full scale. It seems that there is not a laminar flow region in core of the jet. Moreover, from the light dynamic variation graph, the jet fluctuation due to the arc voltage behavior maybe is the dominant characteristic of the jet behavior.