Rapid Pulse Discharges: A New Approach to Particulate Filter Regeneration

该项目将研究一种全新的清洁表面的方法，该方法使用脉冲放电来有效地再生发动机排气微粒过滤器。它拥有一流的功能，这使得它在商业和技术上都非常有吸引力。内燃机是世界上主要的动力来源，这一事实预计将持续到本世纪。虽然柴油发动机的二氧化碳排放量低，具有良好的燃油经济性和耐久性，但它们会排放大量潜在有害的颗粒物（PM）。欧盟、美国和亚洲的发动机和车辆法规只有在使用柴油微粒过滤器（DPFs）的情况下才能实现，并计划在2013年进一步减少。如果不定期清洗（再生）dpf，车辆行驶约150英里后dpf就会堵塞，导致发动机排气背压过高，从而导致性能和燃油经济性下降。虽然目前的DPFs通过迫使气体流过多孔陶瓷壁，使PM减少了约95%，但迄今为止的再生系统存在高功耗、不可靠、高成本和材料选择有限的问题，或者只是体积太大、太复杂。本文提出的再生技术的阶梯式变化将实现更理想的系统，并可以将DPFs更广泛地应用于更多的发动机和应用。这里提出的研究将实现非热非氧化再生系统的优点，既没有对过滤器几何形状和孔隙结构的敏感性，也没有令人望而却步的高功耗，笨重，笨重和嘈杂的再生系统。新概念使用脉冲放电快速，非常有效地去除PM从过滤器表面没有氧化。初步结果表明，过滤器内脉冲放电产生的冲击波克服了表面力，破坏了PM与过滤器表面的结合，整个过滤器只需10瓦的电力。过滤器内的压力波和伴随放电的电场的综合作用打破了凝聚的颗粒，并允许使用小逆流从过滤器中有效地去除PM。然后将PM捕获在容器中，随后可以通过坚固且易于控制的电加热器将其销毁，或者压实并储存，从而减少碳排放。其结果是快速、低功耗、耐用、有效和低成本的再生柴油微粒过滤器无积灰。放电的另一个非常重要的优点是，它们被吸引到过滤器内最导电的地方，即，一旦放电清洁了一个区域，它就会自我选择一个PM负荷较高的区域。该研究得到了主要合作伙伴卡特彼勒和3DX-Ray有限公司的大力支持，他们将在资金、设备、人员时间和开发路径方面提供大量支持。这将提高研究的影响，预计研究将在新的科学和技术知识、商业价值和社会效益方面对环境产生很高的影响。

The project will research a radically new approach to cleaning surfaces that uses pulsed electric discharges to efficiently regenerate engine exhaust particulate filters. It has class-leading features that make it potentially both commercially and technically very attractive.IC engines are the major source of motive power in the world, a fact that is expected to continue well into this century. Whilst diesel engines emit low CO2 emissions, and have good fuel economy and good durability, they emit significant amounts of particulate matter (PM) emissions that are potentially harmful. Engine and vehicle legislation introduced in the EU, US and Asia can only be achieved with the use of diesel particulate filters (DPFs) with further reductions proposed for 2013. Without regular cleaning (regeneration) DPFs become clogged after about 150 miles of vehicle operation leading to a high exhaust back-pressure on the engine, resulting in poor performance and fuel economy. Whilst current DPFs yield >95% reductions in PM by forcing the gas stream through a porous ceramic wall, to-date the regeneration systems suffer from high power consumption, unreliability, unacceptably high cost and limited choice of materials, or are simply too bulky and complex. The step-change in regeneration technology proposed here will achieve a more ideal system and could enable wider application of DPFs to a greater number of engines and applications.The research proposed here will achieve the advantages of a non-thermal non-oxidative regeneration system without either the sensitivity to filter geometry and pore structure or a prohibitively high power consumption, bulky, heavy and noisy regeneration system. The new concept uses pulsed electric discharges to rapidly and very efficiently remove the PM from the filter surface without oxidation. Preliminary results suggest that shock waves produced by pulsed electric discharges within the filter overcome surface forces to break the bond of the PM with the filter surface using as little as 10 W electrical power for a whole filter. The combined effect of the pressure waves within the filter and the electric field accompanying the discharge break up the agglomerated particulates and allow efficient removal of the PM from the filter using a small reverse flow. The PM is then captured in a container, from where it can be subsequently destroyed, e.g. by a robust and easily controlled electric heater, or compacted and stored, reducing carbon emissions. The result is the rapid, low power, durable, effective and low cost regeneration of diesel particulate filters without ash accumulation. A very significant additional advantage of electrical discharges are that they are attracted to the most electrically conducting sites within the filter, i.e. once the discharge has cleaned one region it will self select a region with higher PM loadings.The research is strongly supported by key partners Caterpillar and 3DX-Ray Ltd., who will be providing substantial support in terms of cash, equipment, staff time and exploitation paths. This will enhance the impact of the research, which is expected to be high in terms of new scientific and technical knowledge, commercial value and societal benefits to the environment.