| Water hammer is occurred in the system of the pressure water pipeline. In the pipeline, with the flow rate sharply changing, the pressure in the pipeline alters and lifts quickly. Because of the pressure of the water hammer from the water hammer phenomenon has a huge effect to the pipeline, the pipeline may vibrate sharply, deform and even break if it is dealt with inappropriately. The water hammer phenomenon is a very ordinary phenomenon, so we should know the size and the change regulations of the pressure to control the system. A set of the rational theories and calculation methods should be followed.In this thesis, the traditional water hammer theories and mathematic models are introduced firstly. Some problems existed in the theories are pointed.In addition, on the basic of analyzing the traditional water hammer theories, the traditional water hammer equations are compared with the gestalt equations according to counting and analyzing in this thesis. Also the influences of the computing results from the computing methods and the computational formats are explored, the dependability of the equations in computing is checked.Finally, according to the characteristics of the transmission of the water hammer waves, the concept of the water hammer speed is led into this thesis, the new calculation equations of water hammer are set up, and the analysis about the calculation results is done.The chief opinions are:1. To the traditional water hammer equations, the calculation of using characteristic method is defective. But the results that from using the diffusion format are reasonable.2. Using the new water hammer equations set up in this thesis, not only the change regulations of the water hammer pressure are correctly calculated, but also the change regulations of the cross-sectional area of the pipeline and the density of the liquid can be calculate. This thesis has importance in which developing the theoretical researches and guiding the practical application projects. |
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