Research into basic sensor technology for indirect measurement of viscosity and viscosity development of viscous materials by measuring their permittivity

该项目的目的是实现一种技术解决方案，用于非侵入式测量流体粘度及其在管道横截面上的变化。该项目包括对流体的粘度和介电常数之间不完全已知的关系进行基础研究。基于新的发现，层析在线传感器的测量复介电常数在不同的管道的横截面在微波频率范围内和粘度的建立和检查。在该项目中，传感器原理进行了研究，并用于两个不同的应用。这包括液态有机氢载体（LOHC-）化合物的氢负载的空间分辨率的提取。LOHC化合物是一种很有前途的方法，用于储存和运输由可再生能源产生的能量。为了可靠地使用，必须测量LOHC化合物的氢负载，这与储存的能量相关。此外，计划研究非牛顿粘性流体的粘度发展，例如不同管道几何形状中的聚合物熔体。到目前为止，粘胶流体的几何形状和粘度之间的基本关系对于某些配置是未知的，这也将在本项目的过程中进行检查。第一个项目阶段包括设计一个传感器系统，测量作为温度、剪切速率和流体压力的函数的复介电常数。由于流体的平行流变特性，可以提取测量值介电常数和粘度之间的关系。基于以前的调查结果，第二个项目阶段包含一个层析非接触式测量系统的设计，间接测量的粘度比电容率测量。同时，一个合适的试验台，泵送不同粘度的流体通过不同的管道几何形状，实现。为了确定管道单元的尺寸和选择，并研究依赖于zeta值的粘度和管道几何形状的提取方法，进行了并行模拟。第三个项目阶段包括在试验台上测量粘度的局部分辨率。除了验证测量LOHC氢负荷的功能外，测量还用于详细分析取决于管道几何形状和粘度的压降。

The aim of the project is the realization of a technical solution for non-invasive measurement of the viscosity of fluids and its change over a pipe’s cross section. The proposed project includes fundamental researches of the not completely known relation between the viscosity and permittivity of a fluid. Based on the new findings, a tomographic in-line sensor for the measurement of the complex permittivity over different pipe’s cross sections in the microwave frequency range and the viscosity is build and examined. Within the project, the sensor principle is investigated and employed for two different applications. This includes the extraction of the spatial resolution of the hydrogen loading of liquid organic hydrogen carrier (LOHC-) compounds. LOHC-compounds are a promising approach for the storage and the transportation of energy generated by regenerative sources. For reliable use, it is essential to measure the hydrogen loading of LOHC compounds, which correlates with the stored energy. Moreover, it is planned to investigate the viscosity development of non-newtonian, viscose fluids, e.g. polymer melts in different pipe geometries. Until now, the fundamental relation between the geometry and viscosity of viscose fluids is unknown for certain configurations, which will also be examined in the course of this project. The first project phase comprises the design of a sensor system measuring the complex permittivity as a function of the temperature, shear rate and pressure of the fluid. Due to a parallel rheological characterization of the fluids, the relation between the measured values permittivity and viscosity can be extracted. Based on the findings of the previous investigations, the second project phase contains the design of a tomographic contactless measurement system for indirectly measuring the viscosity over a permittivity measurement. Meanwhile, a suitable test stand, which pumps fluids with different viscosities through different pipe geometries, is realized. To dimension and chose the pipeline elements and to research an extraction method of the viscosity and pipe geometry depending zeta-values, parallel simulations are done. The third project phase comprises the measurements of the local resolution of the viscosity at the test stand. Besides validating the functionality of measuring the hydrogen loading of the LOHC, the measurements serve for a detailed analysis of the pressure drop depending on the pipe geometry and the viscosity.