An efficient numerical method with first and second order accuracy is developed by the flux split technology to simulate the water hammer problem in single and multiple pipe networks under severe transient conditions....An efficient numerical method with first and second order accuracy is developed by the flux split technology to simulate the water hammer problem in single and multiple pipe networks under severe transient conditions. The finite volume formulation ensures that both schemes conserve mass and momentum and produces physically realizable shock fronts. The conception of the fictitious cell at the junction is developed. The typical water hammer problem and the experi ment with friction and the comprehensive orbicular network with control valve and pressure relief valve and surge tank are implemented to test the numerical method. Strong numerical evidences show that the proposed scheme has several desirable properties, such as, accurate, efficient, robust, high shock resolution, conservative and stable for Courant number.展开更多
Experiments were conducted to determine the steady-flow characteristics of a variety of top-entry junctions. The observed steady flow relationships are then incorporated into the finite difference of characteristics t...Experiments were conducted to determine the steady-flow characteristics of a variety of top-entry junctions. The observed steady flow relationships are then incorporated into the finite difference of characteristics to simulate the unsteady flow behavior at pipe junctions. Tests under unsteady flow conditions were further carried out and it was consequently clarified that numerical model is capable of accurately predicting flow characteristics in realistic drainage networks.展开更多
文摘An efficient numerical method with first and second order accuracy is developed by the flux split technology to simulate the water hammer problem in single and multiple pipe networks under severe transient conditions. The finite volume formulation ensures that both schemes conserve mass and momentum and produces physically realizable shock fronts. The conception of the fictitious cell at the junction is developed. The typical water hammer problem and the experi ment with friction and the comprehensive orbicular network with control valve and pressure relief valve and surge tank are implemented to test the numerical method. Strong numerical evidences show that the proposed scheme has several desirable properties, such as, accurate, efficient, robust, high shock resolution, conservative and stable for Courant number.
文摘Experiments were conducted to determine the steady-flow characteristics of a variety of top-entry junctions. The observed steady flow relationships are then incorporated into the finite difference of characteristics to simulate the unsteady flow behavior at pipe junctions. Tests under unsteady flow conditions were further carried out and it was consequently clarified that numerical model is capable of accurately predicting flow characteristics in realistic drainage networks.
