论文部分内容阅读
把焊接电弧作为一个发尘点源，应用大气湍流扩散理论，建立了焊接过程中烟尘扩散的数学模型．焊态下焊接烟尘在上升过程中逐渐成发散状态的喇叭口形，其烟尘浓度为一双正态分布函数．烟尘分布区域与湍流扩散系数Ｋ，距电弧发尘点源正上方的距离以及烟尘的上升速度有关．根据试验利用该数学模型计算出不同焊条的湍流扩散系数．结果表明，焊接过程中烟尘的湍流扩散系数比烟尘粒子的热扩散系数（分子扩散系数）大几个数量级．
Using the welding arc as a dust source, a mathematical model of smoke diffusion in welding process was established by using the theory of atmospheric turbulent diffusion. Welding fumes in the ascending process gradually become divergent bell-shaped, the concentration of smoke as a pair of normal distribution function. The distribution of soot is related to the turbulent diffusion coefficient K, the distance directly above the arc dust source and the rising speed of soot. According to the experiment, the mathematic model was used to calculate the turbulent diffusion coefficient of different electrodes. The results show that the turbulent diffusion coefficient of soot during welding is several orders of magnitude larger than the thermal diffusivity (molecular diffusion coefficient) of soot particles.