The gradual opening of the Arctic shipping route has made navigation possible. However, the harm caused by ship exhaust emissions is increasingly severe. Therefore, it is necessary to study the diffusion characteristics of ship exhaust plumes during Arctic navigation. The study focuses on a merchant vessel as the subject of investigation, employing computational fluid dynamics (CFD) simulation techniques to analyze the diffusion characteristics of particulate matter (PM) within ship exhaust plumes under Arctic environmental conditions. The diffusion law of ship exhaust plume PM is clarified, and the influence of three factors, synthetic wind speed, yaw angle and chimney angle, on the PM diffusion is analyzed. It was found that after the PM was discharged from the chimney, the majority of the PM dispersed directly backward along with the external flow field, while a minor fraction lingered at the stern of the ship for an extended period before eventually diffusing backward. Among them, 1235 particles were captured within a range of 200 m from the stern, with a capture rate of 0.6%. When the synthetic wind shows a yaw angle, the capture rate of PM in the interval increases rapidly with the increase of yaw angle, while other factors have less influence on the capture rate of PM. This study provides foundational guidance for predicting PM diffusion from ship exhaust plumes in Arctic environments, thereby enabling more effective strategies for managing such emissions.

In the operation of a high-pressure selective catalytic reduction (HP-SCR) system, variations in the internal exhaust gas flow speed result in non-uniform pressure and temperature distribution within the reactor. These fluctuations, which are neither constant nor linear, can affect the safe and reliable operation of the high-pressure selective catalytic reduction (HP-SCR) system, so the strength simulation analysis is necessary. Based on the high-pressure selective catalytic reduction system of a thermo-fluid-solid coupling marine diesel engine as the research object, this study constructs a calculation model using Space Claim and utilizes computational fluid dynamics (CFD) and computer-aided engineering (CAE) numerical simulation methods to analyze the strength of the high-pressure selective catalytic reduction (HP-SCR) reactor. The results show that the overall pressure drop of the selective catalytic reduction system is 5500 Pa, and the overall temperature rise of the reactor is 24 °C, which mainly occurs in the first layer catalyst, accounting for 62.5%. The pressure and temperature load of the reactor change along the axial direction, and the axial deformation gradient of the cylinder is more. The maximum deformation of the reactor under thermal load is 15 times that under mechanical load, and 97% of the deformation is axial.