Water Hammer Control of Ship’s Trim Balance System

In order to solve the transient noise and vibration problems caused by the water hammer when closing the valve in one ship’s trim balance system, the way of developing the structure, operation method and closing strategy of the valve was studied. Then the new valve’s control effect was verified on the full-scale trim balance system pipeline test bench. The test results showed that, the multi-channel method had a good effect both on the positive and negative pressure water hammer’s control that realized up to 24.9dB of vibration reduction and 95.4% of pressure reduction. Further applying the two-stage control strategy on the basis of the multi-channel method showed better control effect, which raised the pressure and vibration control effect up to 64.3% and 7.3dB respectively.