Design and Analysis of Air-Flow Management System in Air Conditioning

SPIF (single point incremental forming) is a promising manufacturing technique for small batch manufacturing. Furthermore, due to the small plastic zone and gradual nature of the process, the material formability is improved as compared to traditional sheet metal forming processes. However, further advancement of the SPIF method necessitates a thorough understanding the mechanism of material deformation, which is critical for process optimization. In this present study a detailed finite element model mimicking the duct of a HVAC system has been developed to analyze the state of strain and stress in the vicinity of the contact region, where plastic deformation is caused by the forming tool operation. The numerical model is developed in ABAQUS for a truncated pyramid made of Al6082T6 aluminum alloy, which includes the forming force evolution, final thickness, and plastic strain distributions. The blank is modelled with hexahedral finite elements in order to precisely measure the through-thickness gradients. The limited contact area between the forming tool and the blank results in a negative mean stress at the bottom of the tool, delaying the occurrence of ductile fracture. The residual stresses, on the other hand, are positive in the inner wall of the pyramid and negative on the outer wall in both meridional and circumferential directions. Due to the geometrical constraints in this direction, they often occur in the circumferential direction.