Multi‑objective optimisation and experimental validation of a compact energy‑efficient active regeneration burner for diesel particulate filter regeneration

Active regeneration burners are essential for diesel particulate filter (DPF) regeneration. However, they are often constrained by low flow utilisation, excessive gas velocity, and inadequate mixing between combustion products and exhaust gas, leading to poor thermal efficiency and degraded regeneration performance. To tackle these challenges, this study focused on achieving a compact and lightweight burner design via iterative and dimensional optimisation. A multi‑objective optimisation framework incorporating Response Surface Methodology (RSM), Non-dominated Sorting Genetic Algorithm III (NSGA-III), and Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) was then established to enhance the combustion performance. The effectiveness of this optimisation approach was verified through regeneration experiments. The optimised design reduced burner volume and mass by 57.7 % and 39.5 %, respectively, while maintaining outlet velocity uniformity above 97 % across three investigated exhaust-flow conditions. Outlet temperature uniformity increased from 82.8 % to 92.2 %, the maximum measured outlet temperature at the five-point thermocouple plane increased from 865 °C to 970 °C, and thermal efficiency increased from 38.8 % to 51.1 %. The time required for the DPF upstream temperature to reach 600 °C decreased from 200 s to 172 s, while the regeneration efficiency increased from 92 % to 94 %. Smoke opacity, HC, and CO decreased from 3.9 % to 3.1 %, 28 ppm to 8 ppm, and 0.205 vol% to 0.100 vol%, respectively; however, NO x increased from 104.5 ppm to 117.0 ppm, indicating a trade-off between oxidation completeness and NO x formation. These results demonstrate the practical potential of the burner for compact and energy-efficient diesel aftertreatment systems.