Numerical Modelling for the Design of Urban Drainage System

Abstract

Adequate drainage system is of utmost important in any modern urban area. In general, drainage system consists of multiple pipe networks. The principle of a pipe network involves computation of major and minor energy losses due to flow through a pipe. A general pipe network contains many common pipes and single pipes. The solution for pipe network system can be determined using Hardy-Cross method and Newton-Raphson Method. Although Hard-Cross Method has been commonly used by hydraulic engineers since 1936, the slow convergence has been its disadvantage. In this study, we propose a general model for such an urban drainage system through the Newton-Raphson method, which allow users to calculate the pipe system with arbitrary pipe network. Based on the proposed model, we can further provide a design for pipe geometry (including length, diameter, pipe materials) for given inlet and outlet flow conditions. This will provide hydraulic engineers a simple guideline for the design of an urban drainage system.