Problem: The original hydraulic turbine model was HLA551-LJ-315. Since the power plant started operations, it has been affected by the impoundment of the Lubuge hydropower station, The power station tail water changed by more than 15m (rated head 58.5m), resulting in the presence of cracks with varying degrees and cavitation on the outlet edge of the runner blades after each flood season. The power station needs to perform cracks and cavitation repairs on the runner each year, which substantially increases the operating costs of the power station.
New Runner Model: HLGT155-LJ-315
Solution: The full-flow passage CFD simulation was used to optimize the blades shape according to the operating range; the new runner is more suitable for a wide range of head changes, optimizing the water outlet edge of the blade, solving the problem of stress concentration on the blade outlet side, and optimizing the overal blade profile. Using X-shaped blades,a higher weighted average efficiency is achieved over full operation range, while also reached a more uniform pressure gradient of the blade and significantly reducing its cavitation. The new runner has experienced a flood season without any cracks or cavitations. At the same time, the maximum output was increased from the original 52 MW to 56 MW, bringing significant economic benefits to the power station.
CFD flow chart Pressure distribution chart
Cavitation Performance Comparation Efficiency Curve
Power station Installation
Friction transfer torque