Development of advanced particulate filters for automotive applications

一系列立法正在推动对提高燃油经济性和减少排放的需求。这些要求使用新的燃料和发动机技术，例如，可能会增加颗粒物排放。与此同时，出于对颗粒物对健康影响的担忧，有关颗粒物的严厉新法律也正在出台。在这项研究中，我们将研究改进的催化后处理系统的开发，该系统可以应用于交通部门使用的柴油、汽油和天然气发动机。要研究的排放系统的主要方面是颗粒过滤器，包括具有和不具有选择性催化还原NOX化合物(SCR)的组合功能。一项重要的新发动机技术是汽油直接喷射(GDI)，即燃料以类似于柴油发动机的方式喷射到气缸而不是进气口。虽然这提高了燃油经济性，但也会导致排放中的颗粒物。这些颗粒物在几个方面与柴油发动机排放的颗粒物不同。使用实验和复杂的建模技术相结合，我们将研究商业过滤材料中颗粒的产生和捕获。这些结果将有助于我们在微观水平上理解现有结构的效率及其对流动分布的影响。研究结果将为滤清器的材料设计提供依据。另一项重要的研究是通过在过滤器基质上涂抹催化涂层将NO还原官能团直接添加到过滤器中的效果。与整体结构和最佳涂层分配有关的一些问题有待解决，这将理想地导致消除目前使用的单独的脱氮反应。

A combination of legislations is driving the need for improved fuel economy and reduced emissions. These require the use of new fuels and engine technologies that may increase, for example, particulate emissions. At the same time, tough new laws governing particulates are also being introduced, owing to concern over their health implications. In this research we will study the development of improved catalytic after-treatment systems that can be applied to diesel, gasoline and natural gas engines used in the transportation sector. The primary aspect of the emission system to be studied is the particulate filter, both with and without the combined functionality for the selective catalytic reduction (SCR) of NOX compounds. One significant new engine technology is gasoline direct injection (GDI), where the fuel is injected into the cylinder rather than the intake port, in a manner similar to diesel engines. Although this improves fuel economy, it also results in particulate matter in the emissions. These particles are different in several ways to the particulates emitted from diesel engines. Using a combination of experimental and sophisticated modelling techniques, we will study particle generation and capture in commercial filter material. These results will help us to understand the efficiencies of existing structures and their effect of the flow distribution at the microscopic level. The results will allow for better materials design of the filter. Another significant investigation is the effect of adding the NO reduction functionality directly into the filter by applying a catalytic washcoat to the filter substrate. There are a number of issues to be resolved relating to the overall structure and optimal washcoat distribution, which will lead ideally to the elimination of the separate deNOX reaction that is currently used.****