Application of rectangular integral to numerical simulation of hydraulic transients in complex pipeline systems

Abstract

The hydraulic oscillation of surge tank was analyzed through numerical simulation. A rectangular integral scheme was established in order to improve the numerical model. According to the boundary control equation of surge tank, the rectangular integral scheme omits the second-order infinitesimal and simplifies the solving process. An example was provided to illustrate the rectangular integral scheme, which is compared with the traditional trapezoid integral scheme. Appropriate numerical solutions were gained through the new scheme. Results show that the rectangular integral scheme is more convenient than the trapezoid integral one, and it can be applied to the numerical simulation of various surge tanks in complex pipeline systems.

Keywords

rectangular integral / trapezoid integral / surge tank / hydraulic oscillation

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