Optimum Design Parameters of an Automotive Blower Fan Housing Scroll

This paper describes the results of a design of experiment DOE applied to an automotive HVAC blower system. The DOE evaluates the influence of a selected three design parameters of a blower housing scroll on the performance of the blower system, and the interaction between these parameters. The effects of the blower scroll starting angle, defined by a selected clearance between the outer diameter of the blower fan and the nearest point on the scroll cut-off edge, the clearance between the top of the blower fan and its housing scroll, and the type of scroll expansion are concluded. A Three Dimensional computation CFD is used to select the DOE levels of each parameter, based on the inspection of the CFD air flow field, and the produced static pressure field. The DOE results are illustrated by the main effects plots, interaction plots, and the ordered effects of the regression analysis. The “DOE” results and discussion define an acceptable range of the three blower scroll design parameters.