Research On The Liquid Sloshing Properties In Elastic Tanks

The growing needs of liquid-filled ships make its transport security concern in theindustry. These ships’ partial loading condition may cause severe sloshing during the voyage,sloshing has strongly non-linear characteristic, pulse of the impact pressure is neither simpleharmonic nor period, its exact values can’t predict. Impact pressure caused by the sloshingcan cause bulkhead structure damage，and in poor sea conditions also affect the stability ofthe ships. Accurate forecast liquid sloshing loads and response is the primary condition ofliquid-filled ships safety using, also an important step in the design process of liquid-filledships. At present, most studies by scholars from various countries on the sloshing are carriedout for rigid tanks, due to the complexity of fluid-structure interaction problems, research onsloshing phenomenon in elastic tanks extremely rare. Based on reading a lot of relevantliteratures, this paper mainly complete the following aspects of work:1) In accordance with the four classifications the liquid sloshing characteristics in rigidtanks, liquid sloshing characteristics coupled with ship motion, liquid sloshingcharacteristics coupled with baffles and liquid sloshing properties in elastic tanks, madea more comprehensive overview of literatures about sloshing domestic and outsideduring the past five years;2) Established a mathematical model of the flexible tank sloshing, that is the basicequations of fluid motion, the equations of structural motion and boundary conditions.And proposed numerical method that combines finite volume method/display integralsolution method/Arbitrary Lagrange--Euler the three methods to achieve theproblem’s solution;3) Proposed the numerical model of elastic tank sloshing based on analysis of transientdynamics software MSC.Dytran, summed up a set of effective computational methodfor the sloshing of elastic tanks;4) With the "Common Structural Rules for Double Hull Oil Tankers" related contentcarrying out sloshing simulation for316,000tons of Very Large Crude Carrier (VLCC)ship. Used Matlab to program low-pass filter，made the sloshing loads results ofstiffening tank based on calculation of the MSC.Dytran and the CFD resultscomparison, verifying the correctness and feasibility of proposed method in this paper;5) Calculated and analyzed influence of the bulkhead thickness, the external excitation parameters, loading rates and other factors changes on sloshing impact loads andstructure response in elastic tanks;6) The structure response was transformed into the frequency domain, giving a reasonableexplanation of liquid sloshing phenomenon in elastic tanks.