Analysis And Research On Hydraulic Characteristics Method Of Urban Water Network

Urban water supply works is composed of three parts, which are intake water, water treatment, and the pipe network system.The part of the pipe network system, is responsible for delivering clean water to millions of households, in order to guarantee the life of urban residents.As the important municipal facilities, pipe network system is a huge in vestment. The costs of it can account for50%～80%of the total investment of the entire water supply project,,and every year people should invest a lot of money for the renovation, expansion and maintenance. Therefore, understand pipe network system operating condition and timely access to the information of its operating data,managethe pipe network system scientificly is very necessary.Over the years, many domestic and foreign experts, dedicated to its use of the water supply network calculation and analysis methods. With the development and complete of the graph theory technology, people using graph theory to construct to the water supply network node equations and ring equation. The concise matrix in the manner described, the complicated system, the nature of the equation and its application with a more intuitive, more profound understanding of the new solution ideas have been achieved due to computer technology matures.In the development of computer technology, it is easy and intuitive to parsing and applications with Pipe network system and matrix.Network characteristic curve is a description of the pipeline flow Q and the total pressure in the pipeline H curve, which gives a total water pressure of the pipeline in a flow.In the water distribution network design, pump station design, and when the choice of the pumping station will be through the pipeline characteristic curve and the pump characteristic curve simultaneous to determine the the pumps operating point to the completion of the work of selecting a pump.At the same time it is also used in the expansion of the pumping station, pipeline characteristic curve.By the hydraulic calculation,Each pipe section can be understand, but can not like the pipeline characteristic curve reflects the overall pipe network hydraulic characteristic.In the theory, the form of curve had been changed, but most of the researchhave neglected this change, still using the traditional pipeline characteristic curve, which previously led to determine the operating point and the true value of the deviation. About Chengshiguanwang characteristics curve a little research, and are only from the perspective of qualitative analysis of the characteristic curve of the pipe network, there are a lot of limitations. Meanwhile, the pipe network, the characteristic curve is also different pipe network characteristics curve should be analyzed according to the characteristic curve according to the specific circumstances of the pipe network.The least squares method is a mathematical optimization techniques. Minimize the square of the error and the best function to find data matching. Using the least squares method to the unknown data can be easily obtained, and makes these data with the actual data obtained between the sum of squared errors is minimized,and finally get best function.Pipeline characteristic curve based on the use of the least squares method, the method of least squares analysis fitting city to the curve of the relationship between the water supply network water consumption and the most unfavorable pipeline, respectively, fitting a straight line, a quadratic curve and cubic curve, followed by fitting results of the evaluation, to determine whether the curve has a statistically significant, and choose the best fitting curve through the results.