Improvement of Modeling of Laminar Flows in Pressure Collector-Pipelines

Abstract

In the now-a-day’s methods of hydraulic calculation of pressure collector-pipelines, the value of the coefficient of hydraulic friction (Darci coefficient) is assumed to be constant. However, the fluid flow rate along the collector pipeline is variable. It increases along the pipeline at the expense of fluid inflow from jets through inlets in its wall. In the initial segments of long CP the fluid flow is laminar. Farther, with the increase of fluid flow rate, a turbulent stream is formed. In this paper, laminar streams are considered. The variability of Darci coefficient is taken into account. Based on the differential equation of enforced variable flow rate fluid flow along the stream, a mathematical relationship for calculating the fluid inflow into the collector-pipeline has been derived. A formula for calculation of variable along the stream total working head in a collector-pipeline is obtained. The calculational relationships take into account geometric parameters of the CP, the angle of inflow of the jets to the stream, the angle of inclination of the pipeline to the horizon.