安装有空气阀的输水管路系统空管充水过程瞬态分析

在输水管路系统中,空气阀在预防水柱分离及再弥合水锤方面发挥着关键作用。现有空气阀的应用研究多集中于满管流状态,但对于空管充水阶段空气阀的水锤防护研究较少。为此,本文建立了空管充水过程中空气阀的数学模型,提出了一种基于改进牛顿迭代法和直接求解法相结合的求解空气阀模型的计算方法,分析了进气阀、普通进排气阀和进气微排阀3种类型的空气阀在曲折管线空管充水过程中的水锤防护效果。定量分析表明,为预防空管充水过程中出现的水柱分离及再弥合高压水锤,选择大口径进气,微量排气的空气阀最为合适。该研究对安装有空气阀的输水管路系统的空管充水瞬态分析具有一定的参考价值。

Filling transient analysis in pipelines with air valves

Air valve plays a critical role in prevention of column separation and water hammer in pipeline systems. The existing research on air valve application focuses on full pipe flow field, but few studies on water hammer protection with air valve in filling process are considered. To this end,the mathematical mod-el of air valve during pipeline filling is built. A method that combines improved Newton iteration method with direct solving method is proposed in order to calculate the air valve model. On this basis,three differ-ent types of air valves including air admission valve, air inlet and release valve, and air inlet and micro exhaust valve are employed to study the effect of air valve on filling transients. It is indicated that the air inlet and micro exhaust valve is the most appropriate air valve type for the water hammer protection during pipeline filling. This research provides the reference value for the filling transient analysis in pipelines with air valves.