Numerical Simulation of Ventilation System in Engine Room under Ship Construction

Manual welding operations are performed with human efforts inside the ship, when constructing an LNG carrier. Workers for welding inside an engine room are directly exposed to welding fume, by which its long time exposure may lead to serious health issue. In this background, it is important to improve the air quality in the working space by ventilating air using multiple fans. The placement of ventilation fans on site has been empirically determined, but it has yet to investigate if such the fan arrangement is optimal or not. In this study, we introduce a computational fluid dynamics (CFD) model that simulates the interior of a ship engine room using a commercial software ANSYS Fluent. A numerical quantity, i.e., the age of air, is computed using a transport equation with velocity vector field obtained from incompressible Navier-Stokes equations. As a parametric study, we explore various conditions of the fans such as the number, location and angles for a room structure surrounded by wall for each deck. The current study can suggest an efficient arrangement of ventilation fans inside an engine room under construction, which is possibly used for assessing air quality in similar interior models.