Stefani Frank, Gundrum Thomas, Gerbeth Gunter
Forschungszentrum Rossendorf, P. O. Box 510119, D-01314 Dresden, Germany.
Phys Rev E Stat Nonlin Soft Matter Phys. 2004 Nov;70(5 Pt 2):056306. doi: 10.1103/PhysRevE.70.056306. Epub 2004 Nov 16.
The three-dimensional velocity field of a propeller-driven liquid metal flow is reconstructed by a contactless inductive flow tomography. The underlying theory is presented within the framework of an integral equation system that governs the magnetic field distribution in a moving electrically conducting fluid. For small magnetic Reynolds numbers this integral equation system can be cast into a linear inverse problem for the determination of the velocity field from externally measured magnetic fields. A robust reconstruction of the large scale velocity field is already achieved by applying the external magnetic field alternately in two orthogonal directions and measuring the corresponding sets of induced magnetic fields. Kelvin's theorem is exploited to regularize the resulting velocity field by using the kinetic energy of the flow as a regularizing functional. The results of this technique are shown to be in satisfactory agreement with ultrasonic measurements.
通过非接触式感应流动层析成像技术重建了螺旋桨驱动的液态金属流的三维速度场。其基础理论是在一个积分方程组的框架内提出的，该方程组控制着运动的导电流体中的磁场分布。对于小磁雷诺数，这个积分方程组可以转化为一个线性反问题，用于从外部测量的磁场中确定速度场。通过在两个正交方向上交替施加外部磁场并测量相应的感应磁场集，已经实现了对大规模速度场的稳健重建。利用开尔文定理，通过将流动的动能作为正则化泛函来对所得速度场进行正则化。该技术的结果与超声测量结果显示出令人满意的一致性。
