Abstract:The single size multioutlet pipe had some disadvantages, such as big pressure head variation, high cost and difference of velocity from inlet to outlet ofpipe. However, the multiple size multioutlet pipe can solve above problems. A design method for the tapered multioutlet pipeline was proposed. Firstly, a series of optimal diameters were obtained based on Lagrange method and the diameters scopes of multioutlet pipeline were determined. Then, several commercially available pipe sizes that are very close to the diameter obtained in the first stage are selected. By using proposed formula, pipe lengths corresponding to nominal diameters are calculated. The pressure head variation of the pipe with different nominal pipe size can be equal to a desired pressure head variation. The cost of multiplesize pipe is lower than that of single size pipe Because the pipe size decreased with the decrease of pipe discharge, velocity distribution in pipe is uniformity. The cost was lower than that of single size pipe.The design result can be used to engineering operation.
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