Fundamental and Applied Plasma Research

这项计划将利用过去NSF支持下开发的设施和专业知识，开始基础研究和应用研究的实验和理论工作的结合。基础研究将是对异常电流穿透的研究。从经典的电磁场理论和许多实际情况的经验来看，众所周知，高频交流电流并不像直流电流那样均匀地穿透导体，而是局限在一个被称为皮肤层的狭窄表面区域。人们普遍认为，这种经典的趋肤效应是一种不可避免的自然法则；这种假设是不正确的，因为趋肤效应是基于欧姆定律，而欧姆定律并不是根本的。事实上，经典的集肤效应只有在欧姆定律的基本形式和对称性假设适用的情况下才会发生；这种情况对应于层流扩散的电流渗透。在这里要研究的更复杂的情况下，不对称几何被合并，基本欧姆定律被更复杂的形式所取代；这些变化允许发生随机或对流扩散，其结果是电流穿透比层流扩散提供的大得多。应用研究将包括认真尝试使用磁流体等离子体稳定技术来消除钢铁行业使用的电炉中普遍存在的不稳定和对电弧的伤害。偏颇的是，这些电炉提供了美国制造的大约三分之一的钢材。

This program will use facilities and expertise developed with past NSF support to embark on a combined experimental and theoretical effort of fundamental and applied research. The fundamental research will be a study of anomalous current penetration. It is well known from classical eletromagnetic theory and also from experience in many practical situations, that high frequency AC currents do not penetrate uniformly through conductors as do DC currents but rather are confined to a narrow suface region called the skin layer. It is widely presumed that this classical skin effect is an unavoidable law of nature; this presumption is incorrect because the skin effect is based on Ohm's law which is not fundamental. In fact, the classical skin effect occurs only when the elementary form of Ohm's law together with a symmetry assumption apply; this situation corresponds to current penetration by laminar diffusion. In the more complicated situations to be studied here, asymmetric geometry is incorporated and the elementary Ohm's law is replaced by a more complex form; these changes allow stochastic or convective diffusion to occur with the consequence of much greater current penetration than provided by laminar diffusion. The applied research will consist of a serious attempt to use magnetohyrodynamic plasma stabilization techniques to eliminate instabilities endemic and injurious to the arcs in electric furnaces used by the steel industry. Paranthetically, these electric furnaces provide approximately one third of the total steel manufactured in the U.S.