超(超)临界疏水阀开阀水锤及管道振动

针对超(超)临界疏水阀开阀水锤及阀后管道振动问题,运用充液管道振动分析的流固耦合理论及特征线法,建立开阀水锤及管道振动的数学模型,求解得到疏水阀在不同流量特性及不同套筒层数下阀开启时水锤压力、流体流速、管道轴向内力和管道振速的时域曲线。研究结果表明:水锤压力取决于流体的流速与压力相互作用,管道内力受水锤压力影响较大,局部受管道振速影响;额定流量恒定时,线性流量特性下水锤峰值压力明显小于快开特性,流速大于等百分比特性,超(超)临界疏水阀宜选用线性流量特性;随着套筒层数增加,水锤压力峰值和管道轴向内力峰值减小,但开阀初始阶段流速波动和管道振动增加。

Influence of Opening Characteristics for Ultra-supercritical Steam Trap on Water Hammer Induced Pipe Vibration

The calculation model on water hammer and pipe vibration are built to discuss the water hammer and pipe under the ultra-supercritical steam trap during the valve-opening process. The research is based on fluid-structure interaction theory of liquid-filled pipe. The time domain curves of water hammer pressure on the fluid, fluid velocity, pipeline axial internal force and pipeline axial vibration velocity are obtained under different flow characteristics and sleeve layers. The analysis shows that: water hammer pressure is mainly depended on the interaction of flow rate and pressure; the pipeline axial internal force, locally influenced by pipeline axial vibration velocity, is greatly influenced by water hammer pressure. At the same rated flow, the peak of the water hammer pressure under linear flow is significantly less than that of quick-opening flow, while the flow velocity under linear flow is greater than that under equal percentage flow. Thus, linear flow characteristic is best for the ultra-supercritical steam trap. The more layers the sleeve has, the lower the peak of water hammer pressure and pipe axial internal force are when the velocity fluctuations and pipeline vibration increase.