SENSORS: Sensor Arrays for Micro-Control of Electrically Conducted Flows in Magnetic Fields

等离子体和液态金属的控制（在包括高超音速空气动力学、聚变和激光在内的应用中）是一个非常有前途的新兴研究领域。少量的控制可以定性地改变磁流体动力学湍流的强度，并且以这种方式影响系统的传热特性或维持其稳定操作所需的外部功率。本计画的目的是找出可有效进行回馈控制的感测机制。目前，存在两种候选方法：（1）用于测量流域壁处的电流密度的电极阵列，以及（2）用于测量壁处的感应磁场的电极阵列。这个理论/数值研究项目的目标是在社区冒险开发两种类型的传感器阵列之前，确定两种传感方法中的哪一种适合于控制等离子体和液体金属。该项目将集中在原型磁流体动力学和磁气体动力学流动（通道、管道、海崖体、空腔、射流，在磁场、压力和热驱动的情况下），从不可压缩流到可压缩流，从较低雷诺数到较高雷诺数。该项目不仅将确定是电传感还是磁传感更有前途，还将确定传感器所需的规格：需要感测的波动变量（电流、磁感应）的大小、额定功率和带宽、阵列上传感器的密度以及传感器的最佳位置。为磁流体动力学流动控制领域奠定基础。影响声明。解决核聚变、激光和高超音速技术中的关键传感器技术问题。培养等离子体、传感器和控制方面的新的跨学科专家。

Control of plasmas and liquid metals (in applications including hypersonic aerodynamics, fusion, and lasers) is an emerging research area of great promise. A small amount of control can qualitatively change the intensity of magnetohydrodynamic turbulence, and in this way influence the heat transfer characteristics of a system or the external power needed to sustain its operation stably. This project intends to identify the sensing mechanisms that can be effective for feedback control. At present, two candidate approaches exist: (1) arrays of electrodes for measuring the current density at the wall of the flow domain, and (2) arrays of solenoids for measuring the induced magnetic field at the wall. The objective of this theoretical/numerical research project is to determine which of the two sensing approaches is right for controlling plasmas and liquid metals, before the community ventures into the expensive technological effort of developing both types of sensor arrays.The project will focus on prototypical magetohydrodynamic and magnetogasdynamic flows (channels, pipes, bluff bodies, cavities, jets, in the presence of magnetic field, pressure, and thermal driving), going from incompressible to compressible flows, and from lower to higher Reynolds numbers. The project will determinine not only whether electrical or magnetic sensing is more promising but also the specifications needed from the sensors: the magnitude of of the fluctuation variables (current, magnetic induction) that need to be sensed, the power and bandwidth rating, the density of sensors on an array, and the optimal location of sensors.Intellectual Merit. Lay the foundations for the field of control of magnetohydrodynamic flows. Impact Statement. Answering key sensor technology questions in fusion, lasers, and hypersonics. Educating new interdisciplinary experts in plasmas, sensors, and controls.