Study On The Simplification And Calibration Method Of Microcosmic Model Of Large-scale Water Supply Network

The simplification of the micro-model of the water supply network is to delete or omit the pipe or node which has little influence on the hydraulic running state in the pipe network and reduce the number of nodes and pipe sections in the water supply pipe network model by using hydraulic simulation to estimate the parameters,so that we can use small-scale pipe network model to represent a large-scale pipe network model to achieve the purpose of simplification.In this paper,we use simplification algorithm based on the three-dimensional grid simplification algorithm to simplify the ring pipe network,and we extend the quadratic error metric on the geometric space to the generalized quadratic error metric on the network model,which gives a weight for each pipe segment in the pipe network system.The weight for each pipe segment is considered as the errors generated by simplifying this pipe section in the pipe network model,so that we can select the pipe segments that need to be simplified according to the size of the weights.At the same time,the simplification algorithm of the micro-model of the water supply network in this paper is to simplify the pipe by the method of contraction,so that this will produce a new equivalent pipe section.In order to implement the multi-granularity(multi-resolution)pipe network model from the microscopic model to the macro model,we also store the necessary information in the simplified process,so that the simplified micro-model of the pipe network can achieve reverse reduction.As there are some errors in the initial pipe network model and simplified pipe network model,so we need to check it.In this paper,we will combine the sensitivity analysis and DE algorithm to check the pipe network model.Firstly,the sensitivity matrix of the frictional resistance coefficient of the pipe section to the node pressure is solved by the sensitivity analysis method.Finally,the H-W roughness coefficient(C value)of the pipe section is checked by using the DE algorithm and the hydraulic calculation module in conjunction with the sensitivity matrix and the pipe network model calibration.