Transient, three-dimensional potential flow problems and dynamic response of the surrounding structures. Part II: Simultaneous coupling between fluid and structural dynamics (computer code SING-S)

Abstract

In Part I a singularity method was described which is applicable especially to highly transient internal flow problems with any three-dimensional geometry including walls wetted on both sides. In Part II, this model is integrated into the equation of motion of the structure which may be obtained from finite-element methods, for instance. In this way, the coupling between fluid and structural dynamics due to common interfaces between fluid regions and structural members is taken into account. Equations of motion are obtained which simultaneously satisfy the conditions of fluid and structural dynamics. Since these equations are of the same type and have the same dimensions as those describing the structural dynamics, the solution of the coupled problem can be obtained by well-known techniques, such as the method of modal superposition which will be applied here. Results are presented for two examples. The second, more practical one deals with vibrations in the pressure suppression system of a boiling water reactor.