Abstract
The method of simplifying the pipeline hydraulic resistance to a fixed admittance is widely used in fluid network simulation. However, because the change of hydraulic resistance with flow rate cannot be accurately reflected, the fluid network simulation is prone to oscillation or even the calculation failure under low-flow conditions. In this study, a wall friction model is developed, which considers important factors such as pipe length, inner diameter, wall roughness, mass flow rate, dryness, etc., and is used to compute the pipeline hydraulic resistance and estimate the pipeline structure when it is impossible to obtain all the pipe size data. The wall friction model is integrated into the SimFlow fluid network simulation software, and SimFlow is used to carry out simulation experiments of the low-flow operating conditions of the typical pipeline network system and the power reduction process of nuclear power plants. The results show that, compared with the fixed admittance, the wall friction model effectively improves the stability of the fluid network simulation under low-flow conditions.
