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The plume rising height of a ship will directly affect the maximum ground concentration and distance from the source caused by flue gas emission. Ship movement has an important effect on plume rising, but it is often ignored in previous studies. We simulated the weakening effect caused by ship movement by considering the influence of four main parameters (wind speed, ship speed, flue gas exit velocity, and flue gas exit temperature) on the smoke plume rising height, using the computational fluid dynamics (CFD) model (PHOENICS version 6.0 CHAM, London, UK). The main parameters affecting the difference in plume rising height between stationary and moving sources for the same parameter settings are the wind speed and the ship speed. Therefore, we established two simplified calculation methods that corrected the flue gas exit velocity (Vexit′) and the flue gas exit temperature (T′) for approximately simulating the smoke plume rising height of the moving ship using the formula of a stationary ship. Verification cases indicated that the corrected Vexit′ (the average of relative error is 5.48%) and the corrected T′(the average of relative error is 60.07%) not only saved calculation time but also improved the simulation accuracy compared with the uncorrected stationary source scheme (the average of relative error is 135.38%). Of these correction methods, the scheme with corrected Vexit′ is more effective. The intention is to provide some references for the field experimentation of moving ship plume rising in different ports in the future and to further study the mechanism of moving ship plume rising.

This paper showed different plume behaviors of exhausts from different number of stacks of the container ship, using CFD code PHOENICS version 6.0. The plume behavior was quantitatively analyzed by mass fraction of the pollutant in the exhaust and plume heights. Three simplified typical configurations were constructed by CFD according to the investigation of container ships. The configurations included a single main stack (BL1), one main stack and multiple auxiliary stacks (BL2), and two main stacks and multiple auxiliary stacks (BL3). All the main stacks had the same emission characteristics, and all the auxiliary stacks had the same emission characteristics. The results show that the transmission and diffusion characteristics of the exhaust from multiple stacks are different from those of the exhaust from a single stack. In BL2 and BL3 simulations, the maximum mass fraction of SO2 in the exhaust (C1max) of multiple stack emissions was approximately 329% and 269% higher than that of single stack emissions over the main stack, respectively, and the plume height of multiple stack emissions is higher than that of single stack emissions. In BL2 and BL3 simulations, the plume height of multiple stack emissions was 41% and 75% higher than that of single stack emissions, respectively. The increase of C1max, due to multiple stack emissions, is weakened as the distance of the stacks increase. The difference in plume behavior between multiple stack emissions and single stack emissions is of great significance for air quality management and pollution control in port areas.