Development of a New Measurement Technique for Phase Equilibria of Fluid Mixtures

提出的研究项目的主要目标是基于微波重入腔技术开发一种新的流体混合物相平衡测量技术。这项新技术将产生一个完整的相位描述（包括压力、温度、成分和密度），为流体混合物的汽液平衡从一个单一的设备，在单一和快速的测量，没有采样。由此产生的设备将推进当前最先进的测量科学与热力学性质研究。总的来说，不断推动更有效和更环保的能源转换暴露了现有热力学模型的局限性，往往导致过度设计和低效的过程设计。解决方案在于开发更精确和全面的流体状态预测方程，这对技术应用很重要。因此，进展最终取决于能否获得相关流体混合物的准确数据。通过传统方法获取此类数据通常是一个非常缓慢的过程，需要使用一套不同的设备（例如，用于相平衡和密度）。每个仪器都专注于测量单一属性，因此需要将混合物加载到多个设备中，并且通常使用分析方法进行表征，这以花费时间和增加不确定性为代价。为了解决这一持续的挑战，本提案旨在开发一种新的流体混合物相特性测量技术，该技术比传统技术更快、更简单。实现这一目标包括(1)基于基于有限元建模的新设计的微波再入腔的构建，(2)获得完整相位描述所需的数学框架的发展，以及(3)新技术原理的彻底证明。

The key objective of the proposed research project is the development of a new measurement technique for phase equilibria of fluid mixtures based on microwave re-entrant cavity technology. This new technique will yield a full phase description (incl. pressure, temperature, composition and density) for the vapour-liquid equilibrium of fluid mixtures from a single device, in a single and fast measurement, without sampling. The resulting device will advance the current state-of-the-art in measurement science associated with thermodynamic property research.Overall, the continual drive to more efficient and environmentally friendly energy conversion is exposing the limitations of existing thermodynamic models, often resulting in over-engineered and inefficient process design. The solution lies in the development of more accurate and comprehensive predictive equations of state for fluids important for technical applications. Therefore, progress is ultimately reliant on the availability of accurate data for relevant fluid mixtures. Acquiring such data by traditional means is usually a very slow process employing a suite of different apparatuses (e.g., for phase equilibrium and density). Each instrument focusses on measuring a single property, thus requiring mixtures to be loaded into multiple devices and often characterised using analytical methods at the expense of time and increased uncertainty. To address this ongoing challenge, this proposal aims to develop a new measurement technique for the phase properties of fluid mixtures that is faster and simpler than conventional techniques. Achieving this aim includes (1) the construction of a microwave re-entrant cavity based on a new design derived from finite element modelling, (2) the development of the mathematical framework required to obtain the full phase description and (3) a thorough proof of principle of the new technique.