气动疏水阀冲蚀工况数值模拟及结构优化

Numerical Simulation on Erosion of Pneumatic Drain Valve and optimization on structure

采用Eulerian-Lagrangian多相流模型对Y型气动疏水阀的内部流场进行了模拟分析。通过将模拟结果与现场运行的阀门的实际状况进行对比验证了模拟的准确性。研究发现阀门密封处液滴速度大于破坏阈值速度,此处冲蚀损伤严重。为减低阀门冲蚀损伤,提出通过阀内流体中液滴对撞来降低液滴速度方法。基于此思想,在疏水阀密封封面前加装节流套装置。发现液滴速度下降了52%,冲蚀损伤大幅下降且位置远离密封面,但质量流量下降到无节流装置的56.5%。为了提高质量流量,进而提出采用循环对流式迷宫式盘片组件作为阀芯的设计。模拟计算发现阀门液滴最大速度为78.6 m/s,仅为无盘片阀门的46%,同时的质量流量为未加盘片阀门的78.2%。采用循环对流式迷宫式盘片组件作为阀芯的疏水阀适用于冲蚀严重的工况。

In this paper,numerical simulations on Y type pneumatic drain valve were carried out using Eulerian-Lagrangian model.The simulation results were verified by the experimental ones.It was found that the droplet velocity close to the sealing surface exceeds the threshold values,resulting in serious erosion.To lower down the extent of erosion,a method that a collision of droplets causes a decrease in droplet velocity was proposed.In this way,a throttling unit was assembled inside the Y type pneumatic drain valve and its performance was simulated.The results showed that the maximum droplet velocity decreases by 52% and therefore the erosion is alleviated significantly.However,the flowrate declines up to 56.5% of the valve without the throttling unit.To increase the flowrate,a throttling unit with several plates featuring maze-like channel on the plates was proposed as the vale disk.The simulation results showed that the maximum droplet velocity is 78.6 m/s,46% of the value for the valve without the throttling unit.The flowrate can achieve 78.2% of the value for the valve without the throttling unit.It can be concluded that the Y type pneumatic drain valve with a disk that features maze-like channel on the plates is applicable to serious erosion operating conditions.