Song Haiqin, Zhang Jinfeng, Zhang Fan
National Research Center of Pumps, Jiangsu University, Zhenjiang, 212013, China.
Sci Rep. 2022 Jun 7;12(1):9351. doi: 10.1038/s41598-022-13320-z.
The vertical long shaft fire pump (VLSFP) is mainly used in fire-fighting places far away from land and lacking large amounts of water supply. The paper selected the XBC18-178-240LC3 model of VLSFP as the research object. First, the experimental-numerical hydraulic performance of the single-VLSFP was carried out, and then the hydraulic performance of the multi-VLSFP was analyzed by the same numerical simulation method as single-VLSFP. After that, three rotor models (Z4 model, Z5 model-original model and Z6 model) were designed by modeling software, connected by different length and number of the shaft section under the same total length of the intermediate shafts. Finally, the rotor's strength and critical speed of three models were analyzed and checked via the CFD simulation and the Workbench software. The study mainly found: (1) Through the strength check of the impeller, maximum equivalent stress of the three models was less than the allowable stress of the rotor material, which indicated the structural design of them met the safety requirement; (2) Through the critical speed check of the shafting rotor, the working speed of the VLSFP was lower than 0.8 times the first-order critical speed of the three models, which indicated the rotor could avoid the resonance and the structure of the three models met the dynamic design requirement. According to the stress check of the impeller and the critical speed check of the shafting rotor, combining the time and labor cost when the VLSFP was installed and disassembled many times before and after the test or operation, the paper selected the Z4 model to be the optimal model, which could provide a theoretical support for the subsequent structure design optimization of the vertical long shaft fire pump.
立式长轴消防泵（VLSFP）主要用于远离陆地且缺乏大量供水的消防场所。本文选取XBC18 - 178 - 240LC3型号的立式长轴消防泵作为研究对象。首先，对单台立式长轴消防泵进行了试验 - 数值水力性能研究，然后采用与单台立式长轴消防泵相同的数值模拟方法分析了多台立式长轴消防泵的水力性能。之后，通过建模软件设计了三种转子模型（Z4模型、Z5模型 - 原始模型和Z6模型），在中间轴总长度相同的情况下，采用不同长度和轴段数量进行连接。最后，通过CFD模拟和Workbench软件对三种模型的转子强度和临界转速进行了分析和校核。研究主要发现：（1）通过叶轮强度校核，三种模型的最大等效应力均小于转子材料的许用应力，表明其结构设计满足安全要求；（2）通过轴系转子临界转速校核，立式长轴消防泵的工作转速低于三种模型一阶临界转速的0.8倍，表明转子可避免共振，三种模型的结构满足动态设计要求。根据叶轮应力校核和轴系转子临界转速校核，结合试验或运行前后立式长轴消防泵多次安装拆卸时的时间和人工成本，本文选取Z4模型为最优模型，可为后续立式长轴消防泵结构设计优化提供理论支撑。
