Flow past oversized normal walls in a duct

In the present technical note, the drag characteristics of two-dimensional wall-mounted circular cylinders and equiangular prisms (wall bodies) are reported. Comparison of drag data for model mounting with and without end gaps are made at identical blockage ratios. Visual observations indicate that the lower forebody pressure for wall body model is caused by appreciable deflection of the flow approaching this model. For models with finite end gaps this flow deflection is not excessive at comparable blockage. This causes the drag force to be lower for wall bodies. When the wall body is in the form of a circular cylinder, Reynolds number effects should be considered besides blockage.