【作者】 张波；

【导师】 储金宇； 陈志刚；

【作者基本信息】 江苏大学 ， 环境工程， 2003， 硕士

【摘要】 应用电晕等离子体对焊接烟尘进行就地净化的技术，是一项新的焊接烟尘净化技术。这项技术把静电除尘的基本原理和烟尘控制方法结合起来，从而达到就地净化开放性烟尘的目的。 电晕等离子体就地净化焊接烟尘装置由电源控制器、高压发生器和高压静电场三部分组成。电源控制器控制电源的启动和过电流保护作用，高压发生器将输入的交流电进行整流—逆变—升压—倍压整流后，通过电缆向发生环输送直流负高压。这样，发生环与“地”(即焊件)之间就形成一个高压静电场。在静电场中，电晕线周围的空气被电离，产生大量正负两种离子，正离子向阴极(即发生环)方向运动，负离子向阳极(即尘源)方向运动。负离子在向尘源方向运动过程中，使尘粒荷电。粒径大于0.5μm的尘粒以碰撞荷电为主，小于0.2μm的以扩散荷电为主。在尘源表面上的一部分尘粒荷电后就粘附在尘源上不能飞扬；另一部分已经飞扬起来的尘粒荷电后，在电场力(包括库伦力、离子风力等)和尘粒自身的重力作用下迅速返回尘源，从而达到就地净化的目的。 本文分析电场数值计算的各种方法，采用模拟电荷法计算电晕等离子体就地净化电焊烟尘的高压静电场；建立电焊烟尘净化的有关的数学模型，在大气污染扩散模型的基础上推导电焊烟尘扩散模型，以及场致荷电模型和扩散荷电模型，同时从概率论上推导净化效率的理论公式，分析净化效率与哪些参数有关；从经济实用的角度出发，设计高压脉动直流电源，以及主电路、振荡电路、逆变电路、倍压电路的分析，部分电路的仿真和测试；通过理论研究和试验研究进行等离子体发生环的优化设计，研制超小型实用化的等离子体发生环；采用滤膜重量法测定净化效率。更多还原

【Abstract】 It is a new technology that welding soot is purified with corona plasma right on the spot.The technology combines rudiment of ESP with method of controlling somke and dust,thus attaining the aim purifying somke and dust right on the spot..The device purifying welding soot with corona plasma consists with power controllers high voltage generator and electrostatic field. The power controller’s function is controlling start and protecting excessive voltage and excessive current.The hight voltage generator supplys loop with negative high voltage through high voltage cable,me inputting AC passing by commuating -inverting -boost-multiplier. So a electrostatic field is formed in the loop and "ground"(welding workpiece).In electrostatic field,the air surrounding corona line is ionizated and a great quantity positive and negative ion is generated. The positive ion moves toward cathode(generating loop) and the negative ion moves toward anode(welding workpiece). The negative ion makes dust carrying charges in the process.The dust which size exceeds 0.5 # m carry charge through crashing,which size exceeds 0.2 # m through diffusing.One dust on the face of welding workpiece adheres afer being carried charge and can’t float in the sky;the other having floated in the sky quickly returns wokpiece with electric field power(kulun power , force of ionic wind)and its gravity afer being carried charges ,thus attaining the aim purifying somke and dust right on the spot.The paper analyzes all kinds method of computing electric fields’s strength,employs simulating charge method computing the electric field’s strength,establishs mathematical models relevant to purifying welding soot.The paper conducts welding soot diffusing model base on the model of air pollution diffusion, the model earring charge by electric field and diffusion and purifying efficiency theoretical formula through probability, in addition to anlyzing which parameter relevant to purifying efficiency.A high voltage pulsing DC power is devised with economic an useful method.The paper analyzes main circuit, oscillatic circuit , inventing circuit and multifying circuit,some circuits are imitated and tested.The loop generating plasma is devised through theoretical an trial research. The purifying efficiency is mensurated with weight filter method.更多还原