Research On Integrated Experimental Equipments Of Ship Fin Stabilizer/Anti-rolling Tank

At present, single stabilization equipment is mainly used to decrease the ship rolling angle in stabilization technics, while there are some limitations in function when fin stabilizer or anti-rolling tank is used solely. (1) Because the fin's lift force is in proportion to ship speed, so the fin stabilizer has better stabilization effect at higher speed, it almost loses function at lower speed or zero speed. (2) Although anti-rolling tank can decrease roll angle at each speed, compared with fin stabilizer, it has lower stabilization capability. (3) Fin stabilizer has the best stabilization effect at beam sea, but has worse or no effect at other wave direction. Passive anti-rolling tank works depending on its natural period, when wave period is different obviously from its natural period, the prospective effect can't be reached by tank and perhaps the phenomenon of increasing roll angle can be caused by tank.While the integrated stabilization method can combine the merits of fin stabilizer and anti-rolling tank to decease ship's rolling angles effectively at each speed. At the time theoretical research is taken on integrated stabilization of ship, synchronously the integrated stabilization experimental equipment is set up, and according to its characteristics the integrated stabilization mathematical model is analyzed, the realization method on experimental equipment and also the test are studied, these can provide theory and test foundations for ship equipped with integrated stabilization equipments.The paper is based on synthesizing numerous literatures and reference materials at home and abroad, the related theories of fin/tank integrated stabilization are deeply studied and the characteristics of experimental equipments are analyzed, the methods used to realize integrated stabilization on experiments are determined, then the simulations and tests are carried out.Firstly, the mathematical models' characteristics of ship-fin stabilizer and ship-passive anti-rolling tank are analyzed, the integrated stabilization model of fin/tank is set up and the influences on roll motion equation are discussed after fin and tank are applied in integrated stabilization system. The influences of actions between fin and tank on static characteristics and integrated stabilization effect are researched.Secondly, the characteristics of integrated stabilization experimental equipment are analyzed and the method used to simulate parameters of ship rolling equation by platform is studied, the test has been done to research the damping coefficient of test platform. The integrated stabilization test-bed is set up on base of combining fin stabilizer and tank equipments, their parameters are determined and the influence of tank dimension variation on related parameters are studied, the servo system model of platform in test-bed system is introduced and also the wave theory is analyzed and simulation is finished.Thirdly, combined the characteristics of the integrated stabilization experimental equipments, the key problems and two methods are brought forward to realize the integrated stabilization system on experimental equipment through analyzing the mathematical model, the simulation results are studied and analyzed between the binomial equation method and roll non-dimensional extinction coefficient method.At last, the tests research on experimental equipment are performed to check the feasibility of moment feedback, the veracity of platform simulating ship roll motion. The period of passive anti-rolling tank, the stabilization effects of anti-rolling tank, fin stabilizer and integrated stabilization system are measured and contrasted.