ESDU 84015 provides a graphical method for predicting the drag and lift (that is@ crosswind force) on each of a pair of closely spaced equal diameter cylinders having their axes parallel and normal to the flow. The method was derived from a correlation of experimental results extracted from the literature and applies to spacings between the axes in the range from one (cylinders touching) to 50 diameters for a range of incidences of 0 to 90 degrees (that is for cylinders in tandem round to cylinders side-by-side). The cylinders can be smooth up to moderately rough@ and the Reynolds number range is from 1E4 to 1E6. The data can be used for pairs of pipes@ cables@ masts@ or cylindrical structural members directly@ and@ using correction factors for finite length and shear flow effects in ESDU 81017@ can also be applied to stacks and towers. Also included are descriptions of the flow mechanisms@ caused by interference between the flows around the cylinders@ which lead to the forces on the cylinders differing from those on an isolated cylinder.
ESDU 84015-1984 history
1984ESDU 84015-1984 Cylinder groups: mean forces on pairs of long circular cylinders.