i 摘 要 关键词： ii Abstract With the rapid development of society and peoples living standards, our countrys economic construction enters into the rush hour. Various industries and regions with the growing water consumption, the pace of urbanization construction is also more and more quickly. Water resources distribution is not with the demand and distribution area all over the world, which makes the emergence of surplus in some poor places. In order to meet the water consumption in each region, the state and local government spend a lot of manpower and material resources in supporting the construction of the water long distance conveyance project, such as dalians lead and the south-to-north water transfer project. With the project of water occurring pipe explosion problem ,it will bring huge economic loss, and therefore solve the problem of pipeline explosion .This will be the the most important and first and foremost work. Long and large diameter pipe gravity flow of the water conveyance project of explosion protection technology is an important technology of the pipeline safety operation , so we have the necessary proof techniques in depth study. This article calculates and analyzes gravity flow water hammer, through the chengdu water sand west to long distance water distribution pipeline project with long distance and large diameter and Multi-Branch pipeline. With the purpose of ensuring pipeline safe operation and avoiding the accident of water hammer, we forecast and analyze the water hammer problems which can occur in the water operation process system, and determine reasonable and reliable water hammer protection measures to reduce the economic loss. In this paper, chengdu water sand west to the waihuan ShuPeiShui long distance pipeline engineering as an example, we study water hammer protection theory. The research results have higher reference value and reference of the similar kind of long and large diameter much pipe gravity flow water supply project of water hammer protection. Key words: Long and large diameter multi-branch pipe gravity current Water Hammer Protection Exhaust valve Pressure regulating tow iii 目 录 第一章 绪论 . 1 1.1 . 1 1.2 . 2 1.2.1 . 2 1.2.2 . 3 1.3 . 3 1.3.1 . 3 1.3.2 . 4 1.4 . 6 第二章 水锤防护的理论计算参数和边界条件计算 . 8 2.1 . 8 2.2 . 8 2.3 . 9 2.3.1 .