Fault Diagnosis of the Blocking Diesel Particulate Filter Based on Spectral Analysis

Shuang-Xi Liu,Ming Lü

doi:10.3390/pr7120943

Abstract

Diesel particulate filter is one of the most effective after-treatment techniques to reduce Particulate Matters (PM) emissions from a diesel engine, but the blocking Diesel Particulate Filter (DPF) will seriously affect the engine performance, so it is necessary to study the fault diagnosis of blocking DPF. In this paper, a simulation model of an R425DOHC diesel engine with wall-flow ceramic DPF was established, and then the model was verified with experimental data. On this basis, the fault diagnosis of the blocking DPF was studied by using spectral analysis on instantaneous exhaust pressure. The results showed that both the pre-DPF mean exhaust pressure and the characteristic frequency amplitude of instantaneous exhaust pressure can be used as characteristic parameters of monitoring the blockage fault of DPF, but it is difficult to monitor DPF blockage directly by instantaneous exhaust pressure. In terms of sensitivity, the characteristic frequency amplitude of instantaneous exhaust pressure is more suitable as a characteristic parameter to monitor DPF blockage than mean exhaust pressure. This work can lay an important theoretical foundation for the on-board diagnosis of DPF.

Highlights

With the development of the economy and the progress of science and technology, the automatic industry has developed rapidly
3, the results of power fuel economy underin external agreed wellsimulation with the experimental dataperformance of the dieseland engine, economy under external characteristics agreed well with the experimental data of the diesel engine, and the calculation errors were less than 5%, which suggests that the simulation model is correct and andbe the calculation errors were less thancharacteristics
Is a way to understand the situation of particulate depositions in the diesel particulate filter (DPF) so that we can diagnose the blockage extent

Summary

Introduction

With the development of the economy and the progress of science and technology, the automatic industry has developed rapidly. To avoid the blockage fault of DPFs and to satisfy the increasingly stringent emission regulations, we need to monitor and diagnose the blockage situation of DPFs so as to clean particulates at the proper time. A simulation model of a R425DOHC diesel engine with wall-flow ceramic DPF was established, and the model was verified. On this basis, the effects of different blockage extents on the mean exhaust pressure of pre-DPF and the effects of different blockage extents on instantaneous exhaust pressure and its frequency spectrum were studied, and the sensitivity of mean exhaust pressure and characteristic frequency amplitude of instantaneous exhaust pressure with an increase in particulate depositions in DPF were comparatively studied

Simulation Model and Validation

208.9 Results

Effects of Different Blockage Extents of DPF on Mean Exhaust Pressure

Conclusions