Flow control using porous magnetic materials

使用多孔磁性材料进行流量控制

• 批准号: 238054700
• 负责人: Professor Dr.-Ing. Jürgen Eckert
• 金额: --
• 依托单位: Lehrstuhl für Materialphysik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/238054700?language=en
• 关键词: Flow; control; using; porous; magnetic

Our project proposal - Flow control with porous magnetic hybrid materials - in the framework of the SPP 1681 has the goal to develop a magnetic hybrid material whose flow properties can be controlled by an external magnetic field. A hybrid material consisting of shape anisotropic magnetic microparticles and an elastic matrix with channels will be prepared and studied for its magnetic, mechanical, and fluid-mechanical properties. The change of the channel geometry in this material is triggered by tilting the external magnetic field and the associated change in angular position of the particles, which in turn deform the matrix elastically. By changing the shape of the channel cross-section (e.g. from circular to elliptical), a reduction of the hydraulic diameter and consequently an increasing pressure drop can be achieved.External controllability of fluid mechanical properties in such a membrane could have a variety of applications, for example as a separator, or as a part of the separator in a Li-/Na-ion-battery whose permeability e.g. for the transport of ions, need to be limited in the case of excessive heat generation in the battery. This becomes more important the larger the battery stack becomes, e.g. in smart grid devices. Similarly, applications in the field of filtration, for example of drinking water, are interesting. Here, the filter would benefit of two important characteristics of the proposed hybrid material. One hand, one could regulate the hydraulic diameter, and hence the pressure drop across the filter and the volume flow through the filter by using the external magnetic field. Other hand, one could tackle the problem of biofouling, i.e. the progressive accumulation of bacteria and algae species at the inner filter surface by shaking this surface using an external alternating magnetic, so that the adhesion between the deposits and the surface is reduced and they can be transported outside. In a further application, a pumping effect in the channels of the hybrid material could be generated by a changing gradient field, so that there is a transport of liquid through the material.In the first funding period of the SPP, we plan to demonstrate the feasibility of such a novel magnetic actor materials. For this purpose, a comprehensive work plan is proposed, which includes the microscopic, magnetic, and mechanical characterization of the components used and of the final hybrid material. Due to its highly interdisciplinary nature, it is necessary to conduct intensive cooperation with working groups in related fields.

我们的项目提案——多孔磁性混合材料的流动控制——在 SPP 1681 的框架内，目标是开发一种磁性混合材料，其流动特性可以通过外部磁场控制。将制备由形状各向异性磁性微粒和具有通道的弹性基体组成的混合材料，并研究其磁性、机械和流体机械性能。这种材料中通道几何形状的变化是通过外部磁场的倾斜和颗粒角位置的相关变化而触发的，这反过来又使基质发生弹性变形。通过改变通道横截面的形状（例如从圆形变为椭圆形），可以实现水力直径的减小，从而增加压降。这种膜中流体机械性能的外部可控性可以有多种应用，例如作为分离器，或者作为渗透性例如为10000mAh的锂/钠离子电池中的分离器的一部分。对于离子的传输，需要在电池中产生过多热量的情况下进行限制。电池组越大，这一点就变得越重要，例如在智能电网设备中。同样，过滤领域（例如饮用水）的应用也很有趣。在这里，过滤器将受益于所提出的混合材料的两个重要特性。一方面，可以通过使用外部磁场来调节水力直径，从而调节过滤器上的压降和通过过滤器的体积流量。另一方面，可以解决生物污垢的问题，即通过使用外部交变磁场摇动该表面，从而减少沉积物和表面之间的粘附力，从而减少沉积物并可以将其转移到外部，从而解决细菌和藻类物种在过滤器内部表面逐渐积累的问题。在进一步的应用中，混合材料通道中的泵浦效应可以通过变化的梯度场产生，从而使液体通过材料传输。在SPP的第一个资助期，我们计划展示这种新型磁力材料的可行性。为此，提出了一个全面的工作计划，其中包括所用组件和最终混合材料的微观、磁性和机械特性。由于其学科交叉性强，有必要与相关领域的工作组开展深入合作。