管道非恒定流特征线法计算中短管问题的处理

针对特征线法用于管网非恒定流数值计算存在的不足不利于处理短管问题，采用调整波速、刚化短管、隐式差分三种方法处理特征线法计算中的短管，设计了一个带阀门的简单管路，并通过计算非恒定流过程中三种方法对阀门端压力值的影响，分析了精度及适用条件，得出采用隐格式处理短管适用范围最广，精度最高。

Solution for Short-pipe Problem in Calculation of Unsteady Flow with Characteristics Method

For the disadvantage of characteristics method used in numerical calculation of unsteady flow in pipe network, it is unfavorable to solve the problem of short-pipe. Adjusting wave velocity method, stiffening short-pipe and implicit scheme method are used to the numerical simulation of unsteady flow with characteristics method, which include a short-pipe. And then it evaluates three methods for the influence of pressure at value by a simple piping system. Finally, the accuracy and applicable conditions of three methods are verified. The result indicates that implicit scheme method for short-pipe is most applicative and accurate.