液体管道非稳定流动摩阻计算

管道中非稳定流动的分析方法主要有频域法和时域法,非线性摩阻的存在给非稳定流动的分析带来一定困难,通常的作法是认为瞬态流动下的摩阻等于稳定流动下的摩阻,但对于管道非稳定流动的长时间的动态模拟,用传统的“拟稳态”假设计算管道摩擦阻力及相关压头损失不够准确,采用频率相关摩中改变这一情况,给出了频率相关摩阻的计算公式及在特征线法中的具体应用。

Calculation of Unsteady Flow Friction in Liquid Pipeline

The main analytical method of unsteady flow in pipelines includes frequency domain analysis and time domain analysis. The existence of the non-linear friction makes the analysis difficult. Usually,the pipeline friction in unsteady flow is regarded as to be equal to that under the steady-state flow. But for long period dynamic simulation of unsteady flow in liquid pipelines,using the conventional "quasi-stationary" hypothesis to calculate the unsteady headless was insufficient. The frequency-dependent friction model can change this situation. Presented in this article is the formula of frequency-dependent friction and its use is MOC (Method of Characteristics).