Multi-source Annular Pipe Cut-off Water Hammer Simulation And Protection Research

With the quickening pace of urbanization, the speed of Chinese socialist modernization construction is in leaps and bounds. The quality of people’s life constantly improve and urban population increased dramatically. It is generally known that as one of the basic modern civilization of urbanization, the function of urban water supply network closely related to people’s daily life. It plays a indispensable role in the whole water supply and drainage system. Therefore, the work of guaranteeing the security of urban water supply and reliability of pipe network gradually get more and more attention. But in the normal water supply daily work, pipe explosion accidents still happen. This directly reflects that there are still many problems to be solved. So far, the research for long distance water conveyance, pipe rolling, high head and large flow of single pipe water hammer protection has considerable achievements, but the research for water hammer in water supply network protection is relatively little. Based on the research results already obtained by gas-liquid two phase flow as the foundation, this dissertation focuses on the optimization of water supply pipe network and water hammer protection in cities.This dissertation expounds the cause of the interrupted water column in two phase flow. Through the establishment of appropriate boundary conditions, it introduces the basic principle of water hammer protection and effective method for present, then establish the calculation model of protection for water hammer. Take the existing water supply pipe network project in Jinan, the capital of Shandong province, as an example, make a computer mathematical simulation of multi-source, high fluctuation and large flow. Then make a brief introduction about the computer program steps of existing urban water supply network water hammer protection. Combining with a water hammer protection instance of Jinan’s water supply pipe network, and use VC++ computer program for simulating the working condition of accident, then compare all the protection plans and choose the optimal one to prevent water hammer accidents.In reference to the research on the past pump-stopping water hammer, this research studies the pump-stopping water hammer protection of the existing urban water supply pipe network. It has a certain reference value and significance for the water hammer protection of existing urban water supply pipe network and its optimization.