Research On Design And Optimization Of Water Hammer Protection For Pipeline Water Transmission Project

With the continuous growth of population and the rapid development of urbanization in China,the discordant distribution of water resources has become one of the most important factors restricting China's economic and social development.For this reason,China has built a large number of water diversion projects for the rational redistribution of water resources,the pump station pipeline project is one of the most common ways of water diversion.For the water delivery project with pressure pipeline,the rapid change of flow rate at any point in the system will lead to the change of flow pattern,or even serious water hammer phenomenon,which will cause great harm to the safety of engineering equipment and personal,which the designer must strictly consider and protect.There are many kinds of water hammer protection equipment.For the increasingly complex large water delivery system,the comprehensive protection scheme including a variety of water hammer protection equipment should be adopted.Therefore,the optimization of many equipment parameters will be involved.Mechanically analyzing the different combinations of many equipment parameters to find the appropriate protection strategy often makes the design work extremely complicated and it is difficult to find the optimal protection strategy.Therefore,it is of great significance and value to select an appropriate optimization algorithm to study the equipment parameter optimization of water hammer protection measures for the protection design and safe operation of pipeline water delivery system.In this paper,based on the background of a water conservancy project,the optimal design and arrangement of water hammer protection equipment in the water conveyance system of the pumping station is studied.The research is mainly carried out from the following aspects:(1)Water hammer calculation program of pipeline water delivery system was written by MATLAB.The program is based on the continuity equation and momentum equation,including the boundary conditions of centrifugal pump,valve,air valve,water shock and discharge valve,etc.,and the method of characteristic line is used to solve it,which has good accuracy and stability.Taking a certain water conservancy project as an example,the hydraulic transition calculation model of pipeline water delivery system in the pumping station was established.In this paper,the worst condition of the pump stopping in an accident in a single-stage pump station is simulated,and the comprehensive protection scheme of the two-stage slow closing valve,air valve and water shock relief valve is determined.(2)Modified Morris screening method and mutual information index method were used to study the sensitivity of the main equipment parameters in the comprehensive protection scheme of water hammer,and the equipment parameters that are most sensitive to the maximum water hammer pressure,the minimum water hammer pressure and the maximum reversing speed of centrifugal pump were determined respectively.In addition,the scenario calculation and analysis of the equipment parameter combination scheme are carried out,and the influence trend of each equipment parameter on the output result of the model is obtained more intuitively,which provides guidance for the parameter identification and optimization design of the water hammer comprehensive protection scheme.(3)Aiming at the diversity of design parameters and the complexity of transient calculation in the comprehensive protection scheme of water hammer,a standard optimization problem with maximum safety as the objective function is defined and solved by particle swarm optimization algorithm.The results show that the particle swarm optimization algorithm(pso)is effective in the optimization design of water hammer comprehensive protection scheme.