Analysis of Hydrofoil Pump Layout and Similarity Theory in Plain River Network Areas

To address the issues of insufficient hydrodynamics and water stagnation in plain river network areas, this study focuses on the typical river network of the Nanxun Campus of Zhejiang College of Water Resources and Hydropower. It aims to optimize the deployment and determine the operational parameters of a bionic hydrofoil pumping device. A 2D hydrodynamic model is built using MIKE21 to simulate flow field characteristics under various conditions, including different placement positions, with or without water-blocking measures, and combinations of flow rate, water level, and flow direction. The impacts of these conditions on system head loss and river velocity are analyzed. Results show that the optimal setup involves deploying the device near the pump house with water-blocking measures, at a flow rate of 1 m3/s, a designed water level of 2.55 m, and a counterclockwise direction. This setup maintains a river velocity of no less than 0.02 m/s, meeting daily water circulation needs. The target hydraulic parameters (flow rate of 1.0 m3/s and head of 0.084 m) are used to propose a similarity theory for hydrofoils, establish scaling relationships, and derive the minimum operational frequency of three serial bionic hydrofoil pumps at 0.268 Hz under this setup. To inhibit algal growth during special periods, the velocity is raised to 0.15 m/s, requiring an increase in frequency to 2.008 Hz. These findings offer a theoretical basis and engineering support for the application and operational parameter design of bionic hydrofoil pumping devices in complex river networks.