本文依据水力学基本原理推导了有压管网水流的最小能量损失原理，并利用网络图论及其矩阵对给水管网进行表示，借助连支、树支管段概论，提出适用于给水管网水力计算和优化设计计算的数学模型。在管网水力计算时，管段初流量分配由计算机自动完成，不需编环号，手工预处理数据 Based on the principle of hydraulics, this paper deduces the principle of minimum energy loss in pressurized pipe network water flow, and uses the network graph theory and its matrix to express the water supply pipe network. With the introduction of branch and branch pipe sections, it is proposed to apply to water supply pipe network hydraulics. Calculate and optimize mathematical models for design calculations. In the hydraulic calculation of the pipe network, the initial flow distribution of the pipe segment is automatically completed by the computer, and the ring number is not needed to manually preprocess the data.