Abstract:In order to study the vortex rope characteristics of the water turbine draft tube and the effectiveness of the Omega vortex identification method on the vortex rope of the draft tube, this paper compared the Q and λ2 criterion and the Omega vortex identification method on the vortex rope of the draft tube, and analyzed the vortex rope characteristics of the draft tube under different operating conditions based on the Omega method and the reduced dimensional Omgea method. The results show that: for radial water turbines, the Q and λ2 criterion, as well as the Omega vortex identification method can identify a clear and reasonable draft tube vortex by adjusting the threshold value reasonably, while the threshold selection interval of the Omega method is small and insensitive. The draft tube of the water turbine will have a long vortex rope in the flow condition, which is not conducive to the stability of the machinery. At the same time, using the reduced-dimensional Omega vortex identification method and the proposed vortex energy index, quantitative analysis of the monitoring surface of the tailpipe under different operating conditions was conducted to determine the area of high vortex concentration, as well as studying the energy dissipation patterns in draft tube. The results show that the area between the inlet and the bend of the draft tube has the highest vortex concentration, the highest energy dissipation and the most unstable flow pattern, which can provide a basis for optimizing the structure of this type of water turbine.
蒋宇浩,汤玲迪*. 基于Omega涡识别方法的径流式水涡轮尾水管涡带特性[J]. 排灌机械工程学报, 2024, 42(): 395-402.
JIANG Yuhao,TANG Lingdi*. Characterization of vortex rope in draft tube of water turbine based on Omega vortex identification method. Journal of Drainage and Irrigation Machinery Engin, 2024, 42(): 395-402.