Seismic response of liquid sloshing in the annular region formed by coaxial circular cylinders

As to the sloshing of liquid in the storage tanks having free surface in earthquakes, there have been many reports, but these are limited to those of relatively simple structures and forms. As the cxamples of complex structures, there are chemical reaction towers, stress removal tanks for BWRs, reactor vessels for FBRs and so on. In these structures, annular parts are formed inside, and as to the sloshing in such annular parts, there is only the report of Aslam et al. In this study, examination was carried out on the earthquake response of the liquid sloshing in the annular part of a double walled cylinder which appears relatively frequently among complex structures. In the analysis, attenuation was taken into account in addition to the method of Aslam et al., the walls of an axisymmetric vessel were regarded as rigid, and infinitesinal displacement and incompressible invicid fluid were assumed. The velocity potential satisfying boundary conditions was determined assuming irrotational flow, and the solution of transient response when n sine waves resonating with the sloshing of first order mode were inputted was derived. Two kinds of double walled vessels were vibrated with a large vibrating table, and the response was measured. (Kako, I.)