- Volume 52 Issue 6
It is important to use bench test results in the design process of anti-rolling tanks. Traditional bench tester is usually designed to perform only roll motions about a fixed axis and relatively small so that the viscous effects may not be neglected. Novel bench tester which could adjust the motion center to realize the coupled motion of sway and roll has been devised and manufactured therefore, large scaled bench tester could be utilized for designing the passive anti-rolling tanks. The time history of the reference signal from the rotation sensor of the bench tester have been recorded and processed to determine the phase angle to derive the Response Amplitude Operator(RAO) of the stabilized ship. The breadth of ART tank model should be large up to 2 m to diminish viscous scale effect and the vertical position of the tank can be varied with the ship's center of motion. The periods and the amplitude of roll motion can be varied from 1.5 sec to 5 sec and up to ±20°, respectively. The components of the tester was expressed in three dimensional digital mockup (DMU) and assembled together in the CAD space. The final configuration of the bench tester has been determined by confirming the smooth operation of the moving parts without interference through the animation in CAD space. New analytic logic are introduced for the determination of hydrodynamic moment and phase difference due to fluid motion in ART and verified through the test. The developed bench tester is believed to be effective and accurate for the verification of stabilization effect of ART taking into the consideration of the sway effect in the design stage.
Bench tester;Coupled sway and roll motion;Passive anti-rolling tanks;Three dimensional digital mockup;Animation
- Watanabe, S., 1969. Motion reduction method (2) by Anti-Rolling Tanks, Workshop report on Seakeeping committee. Tokyo: SNAJ.
- Lew, J.M. Kim, H. & Lee, H.Y., 2003. A Study on the Effects of the Period Control Device of Anti-Rolling Tanks. Journal of the Society of Naval Architects of Korea, 40(1), pp.1-7.
- Lee, B.S. & Vassalos, D., 1996. An Investigation into the Stabilization Effects of Anti-rolling Tanks with Flow Obstructions. International Shipbuilding Progress, 43(433), pp.70-86.
- Kim, H. Lew, J.M. & Ji, J.Y., 2010. Experimental Device of Forced Oscillator for Stabilizer Model of a Ship. Patent No. 10-093461.
- Baek, C.S. Kim, H. & Lew, J.M., 1997. Development of bench tester for designing anti-rolling tanks. Proceedings of Spring Annual Conference of SNAK, Chinhae, pp.24-27.
- Zdybek, T., 1980. The use of bench test results for calculating roll response of the tank stabilized ship. International Shipbuilding Progress, 27, pp.96-105.