Optimal volume selection of air vessels in long-distance water supply systems

Abstract

The use of air vessels is an effective measure to control water hammers, and its volume selection has a certain blindness. This paper aims to reveal the surge wave characteristics and provide design guidelines for air vessels in long-distance water supply systems. First, the analytical formulas of water-level oscillations in the air vessel are derived based on the Krylov–Bogoliubov–Mitropolsky method. Then, an optimization model is constructed for selecting the optimal volume of the air vessels. Finally, the validation of the analytical formulas and the optimization of the model are conducted through two actual projects. The results show that the calculation error of the analytical formulas can be controlled within a very small range, and the process of selecting air vessel volume can be simplified with the provided model. In addition, increasing the air chamber height within its range can reduce the volume of air vessels with the same protection requirements. The optimization analysis results of the air vessel can provide guidance and reference for the design of actual projects. HIGHLIGHTS The analytical formulas for water-level oscillations considering pipe friction are derived.; The volume optimization model can preliminarily estimate the minimum volume of the air vessel.; Under the same protection requirements, the volume of air vessels decreases with the increase of air chamber height.;

Keywords

• air vessel
• analytical formula
• long-distance water supply
• optimization
• water-level oscillation