基于面积折减等效模型的光电倍增管水下内爆机理研究

Underwater implosion mechanism of PMT area reduction equivalent model

光电倍增管(photomultiplier tube,PMT)是中微子探测器的核心部件,是由玻璃材料制成的内部真空的薄壳结构,排列在深水中工作,若一个PMT被压溃会产生内爆冲击波,会引起周围PMT发生殉爆。针对PMT内爆,建立了PMT内爆数值计算简化模型,并将计算与试验结果进行对比,验证简化模型的合理性。在此基础上,提出了基于面积折减等效模型的PMT内爆计算方法,通过等效模型分析了防护装置破口面积对PMT内爆的影响,得出随着防护装置破口面积的减小,水流碰撞发生PMT内爆的时刻相应提前,内爆产生的冲击波脉宽基本保持不变,冲击波压力峰值明显减小。该研究有利于找到有效的PMT内爆防护方法。

The photomultiplier tube(PMT)is the core component of the neutrino detector.It is a thin shell structure made of glass material with a vacuum inside and arranged to work in deep water.Once the PMT is crushed,it generates a strong shock wave,which will cause a blast of the surrounding PMT.Aiming at the implosion of PMT,a simplified simulation model of PMT implosion was established,and the simulation results were compared with the experimental results to verify the rationality of the simplified model.On this basis,the PMT implosion calculation method was proposed based on the area reduction equivalent model,the influence of the breach area of the guard on the PMT implosion was analyzed by the equivalent model.The results show that with the decrease of the breach area of the guard,the moment of PMT implosion caused by the collision of water flow is correspondingly advanced,the pulse width of the shock wave generated by the implosion remains basically unchanged,and the peak value of the shock wave is significantly reduced.This study is helpful for finding an effective PMT implosion protection method.