Mechanisms of Charged Particle Motion during Capture by Charged Droplets in Marine Diesel Exhaust

Abstract

Marine diesel engine emissions of particulate matter pose a significant threat to the environment and human health, necessitating the development of new technologies for their reduction. Among all of these clean and sustainable methods, electrohydrodynamic methods, particularly the use of charged droplets in a wet electrostatic scrubber, offer a viable solution for effectively eliminating particulate matter. This study investigates the basic mechanism of wet electrostatic scrubbers, which involves spraying charged droplets to capture small-sized particles and applying electrostatic forces to act on the oppositely charged particles. In this paper, a mathematical model is presented to describe the process of particle motion when being captured by droplets under the effect of an electrostatic field. Additionally, a co-simulation with ANSYS Fluent and MATLAB is conducted to simulate this process. The mathematical calculation results and co-simulation results are basically consistent, and the average error between these two results is 1.5%. Then, the effect of features, such as electrostatic field strength, particle size, and droplet size, on the particle capture process is analyzed. This study mainly discusses the relationship between the electrostatic field, gas flow field, and particle, motion and proposed a theoretical model and numerical simulation method to describe this mechanism relationship. The research findings provide important evidence for the efficient control of ship pollutants, which is of significant importance for the sustainable development of the international shipping industry.