Flow-making methods for large-scale experimental water tanks by combining pumping and drainage with horizontal–vertical integrated circulation

The choice of flow-making methods is a critical factor in the design and implementation of large-scale experimental water tank flow-making systems, as it directly influences both system performance and operational costs. This study introduces a novel flow-making method that combines pumping and drainage with horizontal-vertical integrated circulation (PD-HVC). This method offers high flow-making efficiency, multiple flow-making modes, and effective space utilization. The determination process of the PD-HVC flow-making method is thoroughly explained, including the proposal of a combined pumping and drainage flow-making method. Numerical simulations were conducted to optimize the layout of the water conveyance corridor, with the horizontal–vertical integrated layout identified as the preferred configuration. On this basis, the PD-HVC flow-making system was designed. The recommended flow-making pump types, flow control system configuration, and the layout strategy for the water conveyance corridor were systematically described. Finally, the feasibility and applicability of the PD-HVC flow-making system were validated through an engineering case study, and its energy consumption characteristics were analyzed. The results show that the current deviation among the pumps under identical frequency conditions remains within 10%, indicating a high degree of operational consistency within the system. While increasing the operating frequency leads to higher energy consumption, it does not significantly affect pump stability or the uniformity of the flow field within the experimental water tank. Moreover, when the pump frequency was set to its rated value, the actual operating power remained significantly below the rated threshold, suggesting the system's potential for over-frequency operation to increase flow velocity under specific experimental requirements. This study aims to provide a technical reference for the process design of experimental water tanks utilizing the PD-HVC flow-making method.