Vehicle heating ventilation and air-conditioning module for improved heating and defrosting performance

An air distribution module (60) for a vehicle heating, ventilation and air-conditioning system (50) receives a layered air-flow of an upper (92) and lower (94) layer for delivery to a vehicle interior. The air distribution module (60) includes a housing (62) defining a central plenum (63) and an air inlet at an upstream side (61) thereof for receiving the layered air-flow of first (92) and second (94) layers. At least a first arcuate duct (74) is coupled to the housing (62) and defines an inner passage wherein the arcuate duct (74) further includes an inlet coupled to a downstream side (65) of the housing (62) and in fluidic communication with the plenum (63). The duct (74) further includes an inversion loop (78) for inverting the air-flow layers and an outlet for discharging the air into the vehicle interior.