Experimental Research on Fluid-Elastic Instability in Tube Bundles Subjected to Air-Water Cross Flow

AbstractFluid-elastic instability is the major factor in causing the vibration of tube bundles. Design guidelines on fluid-elastic instability in tube bundles is necessary to avoid damage due to excessive tube vibration. However, the design guidelines on fluid-elastic instability in tube bundles subjected to two-phase cross flow have no consistent conclusions. Accordingly, this technical note researches the vibration characteristics of three tube bundle distributions, namely, normal square tube bundles with pitch-to-diameter ratios of 1.28 and 1.32 and a normal triangular tube bundle with a pitch-to-diameter ratio of 1.32. Comparison of the present fluid-elastic threshold results with previously published data shows good agreement in single-phase flow. The effects of pitch-to-diameter ratio and tube bundle configurations on fluid-elastic instability induced by air-water cross flow were also compared and analyzed by measuring unstable behavior of tube bundles. It was found that fluid-elastic instability is...