In th e app roach prese nt ed in th is paper, all of th e above difficultie s ar e han dled by  employing engine expe riment s an d using a math emat ical model of th e complete DPF operat ion。 This model includes th e pre- diction of th e flow, temperatur e, an d press ur e distr ibu- tion along th e filter at both steady-stat e an d tran sient conditions。 The unkn own param eters remain th e kinetic constant s to be used in th e NO2-induced reaction with soot, which were fitt ed based  on  th e  expe rimenta l data base of 44  different operat ing point s。

The ma in dra wbacks of th e proced ur e followed ar e relat ed first to th e inh erent difficulty of achievi ng perfectly repe ata ble an d steady-stat e in-engine opera- tion an d second to th e ina bili ty to measur e directly th e soot depletion rat e in th e filter。 The indirect method proposed here, which is based on  th e  measur ement of th e exhau st gas composition before an d after th e filter, is subject to minor inaccura cies when measur ing sma ll differences。论文网

The expe rimenta l an d modeling res ults showed that th e  role  of  th e  NO2   as  a  regenerat ion  agent  can  be

Figu re 8。   Sensitivity ana lysis of  model res ults against th e  reaction kinetic param eters of  th e  NO2  + car bon reaction。

significant at selected operat ing point s when using low- sulfur fuel an d a stan dar d oxidat ion cata lyst ups tr eam of th e filter。 These operat ing point s ar e chara cterized by high NO2 emissions ups tr eam of th e filter。 It is sensed that an optimized oxidat ion cata lyst with an increased reactivity for NO to NO2 conversion would allow much higher potent ial for NO2-assisted soot regenerat ion。 This will be a subject of furth er rese arch。

In regar ds to th e reaction mechan ism of soot oxidation by NO2, an app ar ent Arrh enius-type reaction rat e was foun d to be sat isfactory for all of th e conditions tes ted。 The activat ion energy derived is close to th e report ed values for th is reaction with synth etic gas。 Overa ll, th e model predictions in term s of prediction of th e soot accumu lat ion or depletion rat e in th e filter ar e promis- ing。 The tran sient model is readily applicable to tran - sient conditions, which is espe cially int eresting in order to simu lat e th e filter performan ce in tran sient cycles used for  emissions measur ement of diesel  engines。29摘要：特别在过去的几年里，柴油微粒过滤器（DPFs）的先进技术已经令人印象深刻，通过利益驱 动汽车的微粒排放量逐渐减少。本文涉及 NO 2 是作为在微粒过滤器的煤烟累积的再生过程的活性氧 化剂。在一个宽范围的操作条件下，在现实使用条件对装备有标准的氧化催化剂和微粒过滤器的柴 油发动机进行实验。这些结果被用于验证一个已经可用数学模型再生的在微粒过滤器的 NO 2 辅助现 象。结合使用的实验和模拟结果得出了有关烟灰与 NO2 的化学反应的重要的结论。对这种方法与标准 实验室合成气研究的优势和缺点进行了讨论。在工程方面的实验和仿真结果协议（煤烟累积或耗尽 的速率）是相当令人满意的，并表明这种类型的模型是一种有希望的设计工具。文献综述

关键字：二氧化氮；过滤器；催化剂

实验装置：测试协议 在轻型和重型柴油发动机的排气系统中的微粒过滤的应用重要性日益增加。乘用车

配备柴油微粒过滤器（DPFs）出现在市场，是欧洲达到低微粒排放标准的一种手段[1]。 微粒过滤器技术也被认为是朝着实现重型车辆的废气排放标准的最有希望的解决方案[2-5]。过滤器再生，即，从过滤器烟灰除去的过程中避免过度的背压累积，可通过热烟灰 氧化由废气的氧来实现。发生于在显率温度高于 500-550℃，在这是典型的工作条件下， 很少遇到这种反应。另一方面，NO 2 活性高，带有 NO 2 的反应是能够在温度低至 250℃