Transport phenomena in environmentally friendly energy conversion systems

化石燃料的燃烧提供了世界上大部分的能源需求。液体燃料雾化喷雾广泛应用于燃烧前的燃料制备。雾化质量和喷雾特性对燃烧效率和污染物排放有重要影响。然而，化石燃料的广泛使用导致了环境退化和健康危害。另一方面，燃料电池高效、清洁，并与可持续发展的替代燃料、可再生能源和载体兼容。以氢为燃料的质子交换膜燃料电池(PEMFC)在便携式、移动式和现场热电联产方面最具应用前景，而直接甲醇燃料电池(DMFC)则是以甲醇为燃料的质子交换膜燃料电池。这项拟议的研究集中在(I)液体燃料雾化过程和喷雾特性，因为它们与使用生物柴油等生物燃料的柴油发动机有关，以及(Ii)PEMFC和DMFC中的输送现象及其对性能的影响。这项研究的目的是开发一种预测喷雾模型，该模型可用于实际喷雾燃烧系统的性能预测和成本效益设计，并提高PEMFC和DMFC的性能并降低成本。拟议的研究结果预计将有助于建立现实的喷雾模型，并将有助于评估喷雾燃烧系统的性能，从而开发提高燃烧效率、降低污染物排放和减少开发此类喷雾燃烧系统所需的时间的方法；以及(Ii)预计将有助于提高燃料电池的性能和降低成本，从而促进用于清洁发电的燃料电池的商业化。

Combustion of fossil fuels provides the majority of the world energy needs. Liquid fuel atomization and spray is extensively used for fuel preparation before the combustion stage. Atomization quality and spray characteristics have significant impact on combustion efficiency and pollutant emission. However, the widespread use of fossil fuels results in environmental degradation and health hazards. Fuel cells, on the other hand, are efficient, clean and compatible with alternative fuels and renewable energy sources and carriers for sustainable development. Proton exchange membrane fuel cells (PEMFCs) using hydrogen as fuel are most promising for portable, mobile and on-site co-generation applications, while direct methanol fuel cells (DMFCs) are PEMFCs with methanol as fuel. This proposed study focuses on (i) the liquid fuel atomization processes and spray characteristics as they relate to diesel engines using biofuels such as biodiesel, and (ii) transport phenomena in, and their impact on the performance of, PEMFCs and DMFCs. The objective of the proposed research is to develop a predictive spray model that can be used for performance prediction and cost-effective design of practical spray combustion systems; and to improve the performance and reduce the cost of PEMFCs and DMFCs. The results of the proposed study are (i) expected to be useful in formulating realistic spray models, and will be helpful in evaluating performance of spray combustion systems, thereby developing methods to improve combustion efficiency, to lower pollutant emissions, and to reduce the time required for the development of such spray combustion systems; and (ii) expected to be useful in fuel cell performance improvement and cost reduction, hence contributing to the commercialization of fuel cells for clean power generation.