Analysis of the Power Fluctuations Caused by the Unstable Flow in the Trifurcation of Multi-Turbine Diversion Systems with Common Penstock in Hydropower Units

Energies

Hao Wang¹  Yuanchu Cheng²  Huaiyu Cheng³  Mian Sun⁴  Xinran Guo⁴ 

[1] Wuhan University, Wuhan 430072, China;China National Electric Engineering Company, Beijing 100048, China;School of Power and Mechanical Engineering;The Laboratory of Transients in Hydraulic Machinery, Wuhan University, Wuhan 430072, China;

关键词: hydropower station;    power output fluctuation;    pressure fluctuation;    hydraulic coupled effect;    common penstock;    ANSYS Fluent;   

DOI  :  10.3390/en12152941

来源: DOAJ

【 摘 要 】

Stable operation is a challenge for hydropower stations with multi-turbine hydraulic coupled division systems with a common penstock. In this paper, the serious power fluctuations in a power station with such a division system are analyzed. The fluctuations occur in many conditions without any movement of the regulating system. The mathematical analysis illustrates that pressure fluctuation is responsible for power fluctuations. The computational fluid dynamics (CFD) method provided by ANSYS is used to study the flow pattern in penstocks. The vortex caused by the irrational structure of trifurcation is the reason for pressure fluctuations. Several methods are proposed to optimize the flow stability and three cases are simulated based on these measures. The calculation results of three cases prove the effectiveness of these measures. The measure of setting the new guide plate is finally conducted, and the output power fluctuations vanish. The flow calculation plays a role in the analysis and optimization of the hydraulic system of the hydropower unit. Some rules are summarized from the cases and are helpful in the design of trifurcation in a division system with a common penstock.

【 授权许可】

Unknown