The use of Connors’ equation, or variations thereof, to predict the velocity at which fluidelastic instability occurs in cylinder arrays subject to cross-flow has become ubiquitous. The implicit assumption being that this equation accurately models the physics of fluidelastic instability, and all that is required is to find the “correct” value of Connors’ constant. The evidence for and against this assumption is examined in this paper. Other theoretical models of fluidelastic instability are reviewed and compared with Connors’ analysis. In addition, evidence from experimental data is considered. It is concluded that there are many deficiencies associated with Connors’ equation, and that if better “design guides” are to be obtained, more emphasis must be put on examining the physics of fluidelastic instability.

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