Effect of Side Walls on Flow Past Bluff Bodies

The bluffness of a body is reflected in the steady drag that it experiences in an infinite stream, but this force is increased when the body is in the restricted flow of a channel or duct. The writer seeks to demonstrate a relationship for the drag force between the infinite and laterally restricted flow conditions. Various two-dimensional bluff bodies have been studied experimentally, and the results are compared with earlier analytical studies carried out by the writer. The main parameters relating forces in the restricted flow case to the better documented infinite-stream values are considered, and suggestions are made as to how the results could be applied to other two-dimensional forms. Specific applications are also considered, in particular, the significance of incorrect geometrical modeling for studies in this field.