Air Handling System Optimisation for Fuel Cell Applications

氢燃料电池是一种汽车动力源，与现有的化石燃料相比，它有几个优势。燃料电池不排放有害排放物，只从氢燃料和空气中的氧气中产生电力和水。产生的电力用于为电动机提供动力，类似于电池电动汽车（bev），但使用消耗性燃料而不是单独使用电池，就不需要耗时的充电。氢燃料也可以以“绿色”的方式生产，比如太阳能电解，这比使用化石燃料更环保。这些优点使氢燃料电池成为减少运输部门碳排放的关键技术。为了在电池中进行化学反应，氧气从周围的空气中提供给阴极，但必须通过各种方式进行压缩和管理，以最大限度地提高性能和效率。系统中添加的处理进气和提高燃料电池效率的组件也会导致寄生损耗，通过消耗电能降低整体系统效率。在某些例子中，空气处理消耗了堆栈提供的5%的功率，但可能更多，因此是了解和提高系统效率的关键开发领域。现有的方法可以抵消寄生损失，例如使用涡轮从废气中回收能量，这在涡轮增压柴油发动机中很常见。对于燃料电池来说，这似乎不太有利可图，因为废气流的性质不同。例如，它的温度相对较低，湿度较大，因此含有较少的能量，并且是非脉动的，因此提出了不同的要求和考虑。空气处理组件的这些收益和损失必须在系统层面进行评估，以确保燃料电池的最佳空气管理。关于空气管理解决方案的实用性，还需要考虑进一步的限制，例如避免废气与电气元件接触。这个博士项目的目的是优化氢燃料电池的空气处理系统，特别是重型应用。由于氢的低体积密度（单位体积的能量），燃料电池比轻型电池更适合重型应用。重型车辆往往有足够的可用空间来储存足够的氢气，以满足适当的行驶里程。预期的项目方法如下：对空气路径与燃料电池的相互作用进行研究，了解燃料电池供气的要求和约束。这将有助于了解空气处理组件在项目后期的作用。预计这一阶段将包括文献综述和GT Suite中的数值测试，以补充二手来源的发现。将气流要求与现有的空气管理解决方案相匹配。这将包括进一步的文献综述，以全面评估选择的广度，注意不同组件和配置的作用，效果，优缺点。设计改进燃料电池空气管理的建模技术。例如，这可能是一个湿度模型，它可以更好地代表现实生活条件，并提供更接近物理实验的数据。利用所获得的知识提出新的空气处理系统并进行系统优化。这将使您了解不同配置的优缺点，并随后确定每种配置的最佳应用程序。

Hydrogen fuel cells are a vehicle power source with several advantages compared to the fossil-fuelled incumbents. Fuel cells emit no harmful emissions, producing only electricity and water from hydrogen fuel and oxygen from the air. The electricity generated is used to power electric motors, similar to battery electric vehicles (BEVs), but the use of a consumable fuel instead of batteries alone negates the need for time-costly recharging. Hydrogen fuel can also be produced in a 'green' manner, such as by solar-powered electrolysis, which is more environmentally sustainable than fossil fuel use. This combination of benefits make hydrogen fuel cells a pivotal technology for the reduction of carbon emissions in the transport sector.To feed the chemical reaction in the cell, oxygen is provided to the cathode from the ambient air, but must be compressed and managed in various ways to maximise performance and efficiency. Components added to the system which handle inlet air and improve fuel cell efficiency also induce parasitic losses, reducing overall system efficiency by consuming electrical energy. Air handling consumes 5% of the power provided by the stack in some examples, but could be much more, so is a key area for development to understand and improve system efficiency. There are existing methods to offset parasitic losses, such as using turbines to recover energy from the exhaust flow, as is common in turbocharged diesel engines. This appears to be less lucrative for fuel cells, as the exhaust flow is different in nature. For example, it is comparatively low temperature and is more humid, so contains less energy, and is non-pulsating, presenting different requirements and considerations. These gains and losses from air handling components must be assessed at a system level to ensure optimal air management for fuel cells. There are also further restrictions to consider regarding the practicality of air management solutions, such as avoiding contact of the exhaust water with electrical components.The aim of this PhD project is to optimise air handling systems for hydrogen fuel cells, particularly for heavy duty applications. Fuel cells are more suited to heavy duty applications than light duty due to the low volumetric density (energy per unit volume) of hydrogen. Heavy duty vehicles tend to have sufficient available space that is needed to store enough hydrogen for an appropriate range.The expected project methodology is as follows:1. Conduct research on the interaction between the air path and the fuel cell to understand the requirements and constraints of the fuel cell's air supply. This will help appreciate the role of air handling components later in the project. It is predicted this stage will consist of a literature review and numerical testing in GT Suite to supplement findings from secondary sources.2. Match the air flow requirements to existing air management solutions. This will consist of further literature review to comprehensively assess a breadth of options, noting the roles, effects, pros, and cons of different components and configurations.3. Devise an improvement to modelling techniques for fuel cell air management. This might be a humidity model which better represents real life conditions and provides data which is closer to that of physical experiments, for example.4. Use knowledge gained to propose novel air handling systems and carry out system optimisation. This will provide an understanding of the pros and cons of different configurations and subsequently determine the best applications for each.