安全弁における相変化流体の流出挙動

概要

論文の詳細を見る
The discharging flow rate from safety or relief valves is restricted with the minimum flow area between disk and seat. The flow rate is usually smaller than the calculation with the minimum flow area due to the vena contraction. The non-equilibrium flashing flow model directly using the steam table was proposed to obtain the critical mass flux at the vena contraction. The more precious prediction can be available compared to the previous model using the approximation of steam condition. The discharging flow rate of flashing water through the simple contraction between disk and seat was measured at the different inlet subcooling or two-phase quality. The comparison of the experimental results with the non-equilibrium model indicated the significant non-equilibrium in the flashing flow at the vena contraction in spite of the disk material. The subcooled liquid and two-phase discharging behavior was carefully observed by using the transparent disk. The observation also supported the significant non-equilibrium. The two-phase discharging flow rate was well correlated with the simple pressure loss equation.