Ultrasound Measurement System with adaptive Sound Field for Turbulence Investigations in Liquid Metal Flows

用于液态金属流湍流研究的具有自适应声场的超声波测量系统

• 批准号: 224744747
• 负责人: Dr. Lars Büttner
• 金额: --
• 依托单位: Professur für Mess- und Sensorsystemtechnik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/224744747?language=en
• 关键词: Ultrasound; Measurement; System; adaptive; Sound

At many technical processes that involve liquid metals like steel production, semiconductor crystal growth or flow batteries, the melt flow has a remarkable influence on the product quality and the yield. Turbulent flows have the advantage of a high heat and material transport, but are, however, difficult to simulate numerically. Many applications raise multi-scale problems and require highly spatially resolving calculation grids for large and often complex geometries. Model experiments based on low-melting alloys as working fluid allow for the application of measurement techniques. They pave the way to investigate and understand the complex flow phenomena and hence open a perspective for a process optimization. The project aims for the realization of an ultrasound measurement system with a phased-controlled sound field and its qualification for the investigation of turbulent liquid metal flows in the fields of magnetohydrodynamics and thermal convection flows. In the first funding period the measurement system based on the phased-array principle allowing for sound focusing and steering was set up and characterized. Its functionality was demonstrated successfully at stationary liquid metal flows. The research activities shall be pursued consequently in the here applied second funding period. By improving the measurement properties, the possibilities for applications will be extended towards three-dimensional, highly-turbulent flows. The uncertainty of the lateral velocity component, which in particular is difficult to determine, shall be reduced by a correlation-based estimation algorithm. Using sending and receiving beam forming based on plane wave compounding, a high spatial resolution can be achieved with concurrent high temporal resolution. To cope with the large amount of incurring data, a data compression will be implemented allowing for a continuous measurement time of up to several minutes. As subject of investigation, a Rayleigh-Benard convection experiment will be pursued since the properties of the enhanced measurement system will allow for the first time to study the spatial and temporal structure of the large-scale convection herein. Such convection flows are of high relevancy for natural phenomena in geo- and astrophysics, but also for a multitude of industrial and technical flows. With regard to the energy transition towards sustainable energy, a contribution can be made towards the development of liquid-metal batteries as large-scale energy storage in particular.

在许多涉及液态金属的技术过程中，如钢铁生产、半导体晶体生长或液流电池，熔体流动对产品质量和产量有显著影响。湍流具有高热量和材料传输的优点，但是难以进行数值模拟。许多应用程序提出了多尺度问题，并需要高空间分辨率的计算网格的大型和复杂的几何形状。基于低熔点合金作为工作流体的模型实验允许测量技术的应用。它们为研究和理解复杂的流动现象铺平了道路，从而为过程优化开辟了前景。该项目旨在实现一个具有相控声场的超声波测量系统，并将其用于磁流体力学和热对流领域的湍流液态金属流动的研究。在第一个供资期内，建立了基于相控阵原理的测量系统，并确定了其特征，该系统可进行声音聚焦和控制。它的功能被成功地证明在固定的液态金属流。因此，研究活动将在此处适用的第二个供资期内继续进行。通过改善测量性能，应用的可能性将扩展到三维，高度湍流。横向速度分量的不确定性，特别是难以确定的不确定性，应通过基于相关性的估计算法来降低。采用基于平面波复合的发射和接收波束形成，可以在获得高空间分辨率的同时获得高时间分辨率。为了科普大量的数据，将实施数据压缩，允许长达几分钟的连续测量时间。作为调查的主题，Rayleigh-Benard对流实验将被追求，因为增强的测量系统的属性将允许第一次研究大规模对流的空间和时间结构。这种对流不仅与地球和天体物理学中的自然现象密切相关，而且与许多工业和技术流动密切相关。关于能源向可持续能源的过渡，特别是可以为发展作为大规模储能的液态金属电池做出贡献。