Analysis of dynamic characteristics of whipping effect on l-shaped main steam pipe considering fluid-structure interaction effect

Abstract

To investigate the whipping effect on the L-shaped main steam pipe utilized in the marine steam systems, the fluid-structure interaction (FSI) method is utilized to numerically analyze its dynamic characteristics. The numerical results illustrate that the dynamic response of whipping effect with rupture position B on the oblique pipe section is more severe with the significantly larger displacement of L-shaped pipe and anti-whip restraints and more complex frequency characteristics than that of whipping effect with rupture position A on the right-angled elbow. The mode transition phenomenon is also observed in the case with rupture position B. The maximum deformation concentrates on different parts when burst of pipes occurs at different positions and the deformation with rupture position B is several times larger than that with rupture position A. The increase of gap between anti-whip restraints intensifies the whipping effect, but it also reduces the maximum restraint force. The friction acts as the resistance in the slip process and thus contributes to the protection against whipping effect. The anti-whip restraints E closed to rupture position B on the oblique pipe section has better performance than anti-whip restraints D in the protection against horizontal whipping effect.