טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
Ph.D Thesis
Ph.D StudentFarid Maor
SubjectNonlinear Liquid Sloshing in Partially Filled Tanks:
Modelling, Exploration and Mitigation
DepartmentDepartment of Mechanical Engineering
Supervisor Professor Oleg Gendelman
Full Thesis textFull thesis text - English Version


Abstract

Liquid-filled tanks are widely used in various branches of engineering, including nuclear and aerospace industries, for storage of chemicals, gasoline, water, and different hazardous liquids. Dynamic stresses in such tanks are developed due to various external effects, for instance, earthquakes. Those stresses might increase significantly when slashing is induced, and the resulting stresses might impair or even lead to failure of the tank structure. Failure of hazardous liquids containing tanks may lead to disastrous results and thus the ability to predict and mitigate these stresses is crucial for safe design and operation. However, storage tank design regulations in the USA, Japan and different European countries are based only on linear sloshing models. Moreover, the vast majority of them even neglects the tank shell vibration and its elastic behavior and assumes it acts like a perfectly-rigid structure.


In this research we propose to develop equivalent mechanical system that describes the dynamics main features and nonlinear sloshing regimes relevant for assessment of interaction stresses applied on the tank structure. Moreover, the equivalent system should be as simple and informative as possible in order to serve engineers in establishment of more accurate well-founded equipment design and operation regulations. The analysis uses asymptotic tools and complementary numerical validation for acquiring a deeper understanding on dynamical mechanisms involved. The results are compared qualitatively with available experimental and computational documentations. Finally, different kinds of passive energy absorber are examined as vibration mitigation solutions and numerical optimization method base on novel evaluation criterion is suggested.