Computational fluidodynamic study applied in incompressible air flow in automotive duct 2018-36-0087

The design of air ducts of an Automotive Ventilation System presents as one of the complicators the restriction of space. In its design a symmetrical configuration is not always possible, due to the presence of anothers components of the vehicle, thus the ducts are distributed in asymmetric structures and normally have sharp curves, configurations that contribute to the loss, irregular distribution of the flow and production of noise. This work presents a numerical study of the incompressible flow of air in the ducts of an automotive ventilation system. The purpose is to study and compare the behavior of the fluid dynamic flow, the loss on the process and the flow distribution between two different ducts: one with symmetrical geometry and the other one with asymmetrical geometry. The study was performed using commercial software Star CCM +® that employs finite volume method. The results for each type of duct were relevant to the conclusion that the non-symmetry of the ventilation duct causes significant impacts. The symmetric duct geometry resulted in similar values for the air flow at diffuser placed on right and left side at car console, on the other hand, the asymmetric duct geometry had 7.89% more air flow rate at the right vent compared to the left vent. The pressure found for the symmetric geometry was 3.9% higher than relative asymmetric geometry. With this study, it was possible to visualize the impact that the space constraint, consequently the asymmetrical geometry, induced in the quality of the vehicle's air conditioning system.