In the work presented in this paper, the combined effects of initial temperature and catalyst activity on the regeneration dynamics of a catalytic diesel particulate filter (DPF) have been investigated. To this end, CFD-based simulations of soot combustion in a single-channel configuration were performed. In the model, all the soot trapped inside the filter was assumed to be in contact with the catalyst. The initial temperature of the filter was varied over a wide range independently of the inlet gas temperature, which was kept constant. Numerical results have shown that three main different behaviors arise depending on catalyst activity. At low catalyst activity, as the initial temperature is increased, an abrupt transition occurs from a regime of slow regeneration, characterized by long times (around 10 min) and low peak temperatures (~ 700 K), to a regime of fast regeneration, characterized by short times (< 60 s) and high peak temperatures (up to ~ 1100 K). At high catalyst activity, whatever the initial temperature, regeneration is always a fast process leading to peak temperatures ~ 1000 K. Interestingly, at intermediate catalyst activity, fast regeneration can be carried out with concomitant lower peak temperatures (~ 880 K), provided that the initial temperature does not exceed a threshold limit coinciding with the inlet gas temperature. Under such conditions, the best trade-off between time for regeneration and peak temperature is achieved with the initial temperature of the filter set equal to the inlet gas temperature. This optimal operating point can be further developed in a continuous functioning mode for catalytic DPFs, with regeneration performed during (and not after) filtration at the temperature conditions of the exhaust gas fed to the filter.

在本文提出的工作中，研究了初始温度和催化剂活性对催化柴油颗粒过滤器（DPF）再生动力学的综合影响。为此，在单通道配置中执行了基于CFD的烟灰燃烧模拟。在该模型中，假定捕获在过滤器内部的所有烟灰都与催化剂接触。过滤器的初始温度在很宽的范围内变化，与进气温度无关，进气温度保持恒定。数值结果表明，取决于催化剂活性，出现三种主要的不同行为。在低催化剂活性下，随着初始温度的升高，从缓慢的再生过程中会发生突然转变，其特征是时间长（约10分钟）和峰值温度低（约700 K），再生时间短（<60 s）和峰值温度高（约1100 K）。在高催化剂活性下，无论初始温度如何，再生都是一个导致峰值温度约为1000 K的快速过程。有趣的是，在中等催化剂活性下，可以在较低的峰值温度（约880 K）下进行快速再生。初始温度不超过与进气温度一致的阈值极限。在这种情况下，在过滤器的初始温度设定为等于进气温度的情况下，可以在再生时间和峰值温度之间达到最佳平衡。对于催化DPF，可以在连续运行模式下进一步开发此最佳工作点，