Study On Effect Of Sloshing Phenomenon On Water Level Of Pressurizer

Compared with land-based nuclear power plants,nuclear powered ships will have serious sloshing phenomenon caused by ocean conditions.During the operation of the sea-based reactor,the internal free liquid level of the pressurizer will fluctuate greatly with different ocean cycles,causing additional acceleration in the horizontal or vertical direction,which will cause the water level measured by the differential pressure measurement method to deviate from the actual water level.This will adversely affect the judgment and control of the signal.Moreover,the fluctuating liquid level will frequently trigger the water level alarm signal,resulting in the submersion of the sprinkler tuber and the exposure of the electric heating rod,thereby reducing the safety and economy of the reactor.Therefore,this paper adopts the method of combining experiment and numerical simulation to carry out research on the influence of sloshing phenomenon on the pressurizer.Based on the free liquid level fluctuation phenomenon of the pressurizer under ocean conditions,this paper has carried out theoretical analysis in combination with the actual operation of the pressurizer in the reactor.Considering the liquid level changes in the actual operation of a pressurizer,an experimental system simulating such water level fluctuation of the pressurizer under ocean conditions has been designed and constructed.The experimental study on the water level and pressure fluctuation of the pressurizer under the sloshing condition was carried out using air and deionized water as the working medium and laser induced fluorescence technology(LIF)with high precision.This paper has mastered the law of water level measurement of the pressurizer in different operating states.This paper has analyzed the reasons affecting water level measurement and has corrected the deviation of water level measurement.Based on the experimental results,the simulation model of the pressurizer was established.After the accuracy of the model was verified,numerical studies were carried out on the scheme of the pressurizer suppressing the sway under ocean conditions and the influence of the relative position of the ship metacenter and the pressurizer on the fluctuation of the measured water level.The results show that the transverse oscillation incentive under the average ocean cycle measuring water level in the pressurizer is less affected.Extreme sea conditions close to the natural frequency of the pressurizer can make significant free surface fluctuation.This paper puts forward the related scheme of liquid level stabilizing,results of model calculation satisfies the requirement of reactor operation.Swing incentive under the average ocean cycle have a great influence on the measurement of water level in the pressurizer and the deviation of water level measurement is mainly caused by static pressure change of measuring point introduced by ship inclination angle.The measurement deviation can be reduced to the allowable error range by means of angle correction and measurement method optimization.This paper also puts forward the layout suggestion of the pressurizer relative to the ship metacenter.By means of the acceleration sensor,the deviation of the regulator water level measurement introduced by the up-and-down incentive can be eliminated.