管道是自压喷灌系统的主要设备,其投资占的比重较大,一般为总投资的50～80％。因此,研究管道的优化设计,以减少管材用量和管道工程投资,对降低自压喷灌工程费用,提高喷灌效益,具有重要的意义。自压喷灌的压力管道系统由输水管、配水管、喷洒支管等各级压力管道组成。从水源到灌区上边界的干管叫输水管。灌区内的 Piping is the main equipment of self-pressure sprinkler irrigation system. Its investment accounts for a large proportion, usually 50-80% of the total investment. Therefore, it is of great significance to study the optimal design of pipelines to reduce the amount of pipe materials and the pipeline project investment, which will reduce the project cost of self-pressured sprinkler irrigation and improve the benefit of sprinkling irrigation. Self-pressure sprinkler pressure pipe system consists of water pipes, water distribution pipes, spray manifolds and other pressure pipes at all levels. The main pipe from the water source to the upper boundary of the irrigation area is called the water pipe. Irrigation area