COMPUTATIONAL STUDY OF FREQUENCY IMPACT ONTO THE PARTICLE PARAMETERS AND CHANGE IN ACOUSTIC AGGLOMERATION TIME WITH THE NUMBER OF PARTICLES

Air pollution, especially from particulate matter (PM), is a significant environmental and health issue worldwide. This research examines the use of acoustic agglomeration (AA) as a novel technique to diminish fine particle emissions, concentrating on the influence of frequency on particle characteristics and agglomeration duration. This study aims to improve the effectiveness of traditional filtration systems by investigating acoustic wave-induced particle agglomeration as an alternative method. The research integrates experimental and computational methodologies. Emissions from a 1.9 turbocharged 4-cylinder diesel engine using FAT80IP20 fuel were subjected to analysis in a custom-designed acoustic chamber. Frequencies of 21.2 kHz and 34.6 kHz were used, with particle measurements recorded using a Fluke 985 particle counter. Computational simulations using the Discrete Element Method (DEM) were performed to examine particle behaviour at different acoustic frequencies, accounting for first-order factors such orthokinetic interactions and acoustic wake effects. Results demonstrate that elevated frequencies (34.6 kHz) accelerate particle agglomeration, although the overall quantity of agglomerated particles diminishes. Experimental results indicated a 62.78% decrease in 5 μm particles and a 300% rise in 10 μm particles at 34.6 kHz. The findings correspond with the computer calculations, which indicated that heightened frequency enhances particle mobility and collisions while diminishing the likelihood of prolonged agglomeration inside the chamber confines. The results confirm the efficacy of acoustic agglomeration for emission control, emphasising a frequency-dependent trade-off between agglomeration speed and the volume of agglomerated particles. This study advances the development of sophisticated filtering technologies and more environmentally friendly transportation alternatives.