为实现对商用车后处理系统消声能力的准确评估，满足对整车噪声日益严格的控制，基于流阻率这一重要参数，总结并推导了后处理系统中载体和颗粒捕集器的声学等效模型。其中载体使用复声速、复密度的方法模拟，颗粒捕集器使用等效流阻率下的DelanyBazleyMiki模型模拟，相比于纯空气属性，载体可大幅提高150 Hz以上的消声能力。利用Simcenter 3D仿真传递损失曲线与通过阻抗管设备测得的数据进行对比，数据在1 200 Hz内基本吻合，说明了等效方法可以有效应用于工程实践，对缩短整车开发周期，提升顾客感受有重要意义。

In order to accurately evaluate the noise reduction ability of commercial vehicle aftertreatment system and meet the increasingly strict control of vehicle noise, the acoustic equivalent model of carrier and particulate filter in the aftertreatment were summarized and deduced based on the important parameter of flow resistance. The carrier was simulated by the method of complex sound velocity and complex density, and the particulate filter was simulated by the Delany Bazley Miki model under the equivalent flow resistance. Compared with the pure air property, the carrier could greatly improve the noise reduction ability above 150 Hz. The transmission loss curve was simulated using Simcenter 3D Software and compared with the data measured by the impedance tube equipment. The data were basically consistent within 1 200 Hz, indicating that the equivalent method could be effectively applied to engineering practice, and is of great significance to shorten the vehicle development cycle and improve customer experience.