ANALYSIS OF THE RESULTS OF PERFORATED DRAINAGE PIPELINES CALCULATION IN THE PRESENCE OF TRANSIT FLOW RATE

Abstract

A method of calculating the error that occurs when determining the flow rate in the final section of the pressure perforated drainage pipeline when it passes transit flow rate, based on the analysis of differential equations describing the fluid motion with variable flow rate in such pipelines is proposed in the paper. The analysis is presented in dimensionless form. The impact of transit flow on the main flow is estimated using the values ​​of the drainage pipeline resistance coefficient ζl and the generalized parameter of the perforated drain A, which takes into account its constructive and filtration characteristics. The obtained calculation formulas are quite simple and easy to use. The proposed method allows to perform calculations of drainage pipelines that operate in the presence of transit flow rate, according to the method of these pipes calculation that dispose drain water without passing transit. Herewith, the possible error, which includes in the calculation results, determines. To illustrate the obtained dependences, the corresponding graphs are given in the paper. The results of the analysis allow to determine the limits within which a simplified method of calculating these pipes can be used and the error, that occurs, can be estimated