Performance of flow-induced vibration heat exchanger with conical spiral tube bundle

From the dynamic substructure theory, the vibration of conical spiral tube bundle and the frequency condition of the pulsation element were analyzed using the component mode synthesis method and the super element method. The vibration characteristics of conical spiral tube bundle driven by the transverse pulsation were calculated at a shellside flow rate of 0.1 m/s. The secondary fluid flow inside the tube and its heat transfer were numerically investigated. The results show that the vibration of the single row spiral tube can be divided into transverse vibration and axial vibration, and the latter is dominant. The vibration of conical spiral tube bundle is easy to be induced due to its small low-order mode frequency. Under the condition of pulsating flow, the tube bundle vibration is similar to its transverse vibration mode. The contours of the fluid flow inside the tube indicate that the secondary fluid flow is complicated. There are four independent parts of the secondary flow in each cross section and the flow directions are different from each other. The heat flux of the conical spiral tube bundle is 1.4 times that of the conventional planar elastic tube bundles.