Probing the charge state of ambient and indoor aerosols

气溶胶上的静电荷在全球空气污染、污染控制技术和工业气溶胶过程中起着重要作用。电荷可以影响粒子在全局和微观尺度上的传输行为。它会影响颗粒凝固的方式，并影响它们在肺部沉积的可能性。在工业过程中，粉末的运输和产生会导致颗粒上产生非常高的电荷，在真空吸尘器中也观察到类似的效应。在过滤过程中，静电电荷通常通过影响颗粒上的电荷和过滤纤维上的电荷来提高过滤介质的效率。对不同气溶胶来源的电荷状态的基本理解，即不同大小颗粒上的电荷分布，以及环境和室内环境中颗粒之间的相互作用，可以改善污染控制技术的设计，包括过滤和分离系统。因此，有必要开发有效、快速测量气溶胶电荷状态的测量工具。本博士项目旨在：1.；开发新的气溶胶电荷状态测量技术，可应用于广泛的气溶胶类型、大小和种类。使用实验来量化和评估来自不同来源的不同气溶胶的电荷状态，这些气溶胶可以在不同的室内和环境环境中发现。测量电荷态如何由于粒子相互作用而演变。利用计算流体动力学开发新的建模工具，以解释不同环境中不同气溶胶发生的粒子电荷状态、重组和电荷衰减效应。模型输出将与早期的实验工作进行比较，以了解影响电荷状态的物理现象，这些物理现象可以继续为空气净化装置的设计提供信息。相关研究领域：分析科学、粒子技术、传感器和仪器仪表

Electrostatic charge on aerosols plays a significant role in global air pollution, in pollution control technologies and in industrial aerosol processes. Charge can influence the behaviour of particles as they are transported around at global and micro scales. It influences how particles coagulate and can affect how likely they are to deposit within our lungs. In industrial processes the transport and generation of powders can lead to very high levels of charge being built up on particles and similar effects are observed within vacuum cleaners. In filtration processes electrostatic charge is often employed to improve efficiency of filter media by influencing both the charge on the particles and the charge on filter fibres.Fundamental understanding of the charge state of different sources of aerosols, i.e. the distribution of charge on particles of different sizes, and the interactions between particles in ambient and indoor environments could lead to improvements in designing pollution control technologies, including filtration and separation systems. Therefore, there is a need to develop measurement tools to effectively and quickly measure the charge state of aerosols. This PhD project aims to:1. Develop novel measurement techniques for aerosol charge state that can be applied to a wide range of aerosol types, sizes and species.2. Use experiments to quantify and evaluate the charge state of different aerosols that are emitted from different sources, which can be found in different indoor and ambient environments. Measure how charge states can evolve due to particle interactions.3. Develop new modelling tools utilising Computational Fluid Dynamics that account for particle charge state, recombination and charge decay effects that occur with different aerosols in different environments. The model outputs will be compared to the earlier experimental work to understand the physical phenomena that affect charge state that could go on to inform the design of air cleaning devices.Relevant EPSRC research areas: Analytical science, Particle technology, Sensors and instrumentation