Experimental and numerical investigations of a high-head pumped-storage power plant at speed no-load.

Decaix, Jean; Hasmatuchi, Vlad; Titzschkau, Maximilian; Rapillard, Laurent; Manso, Pedro; Avellan, François; Münch-Alligné, Cécile

doi:10.1088/1755-1315/240/8/082014

Cited by 7 publications

(7 citation statements)

References 5 publications

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“…Only then, the guide vanes are closed completely. The observed frequency of 611Hz compared to the nominal rotating frequency of 12.5Hz (f/fn = 48.9) is very close to the first harmonic of the blade passing frequency and therefore shows the response of one of the runner Eigen modes (see the results presented by Decaix et al [9]). Since this clearly dominating frequencies have been also detected by the external microphone, the proximity sensors and the accelerometers on the turbine casing, further non-intrusive measurements can be done by using this results as a foundation.…”

Section: Frequency Analysissupporting

confidence: 62%

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On-board measurements at a 100 MW high-head Francis turbine

Ttizschkau¹,

Hasmatuchi²,

Decaix³

et al. 2019

Wasserwirtsch

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The Francis turbine runners of the four ternary groups of Grimsel 2 power plant in Switzerland showed fatigue cracks at the runner blades much earlier than expected. To find the source of these cracks, strain gauges and accelerometers were used to get information about the harmful stresses on the runner during operation. It is observed that the speed no-load operation during the start-up and the shutdown processes of the turbine impose large stresses on the runner blades.

show abstract

Section: Frequency Analysissupporting

confidence: 62%

“…The goal is to find out the operating point that leads to the increased fatigue of the material. Therefore, on-board measurements on the runner synchronised with non-intrusive measurements on the machine have been performed, as well as CFD simulations (see Decaix et al [9]).…”

Section: Introductionmentioning

confidence: 99%

On-board measurements at a 100 MW high-head Francis turbine

Ttizschkau¹,

Hasmatuchi²,

Decaix³

et al. 2019

Wasserwirtsch

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“…Due to the varying demand of the power grid for the electric supply of hydraulic power stations, the hydraulic power stations are often under low-load operation and no-load standby state [1] [2]. As turbines are often designed or selected under design conditions, for low-load conditions, such as 50% load and no-load conditions, have significant hydraulic instability, which threatens the safe and stable operation of the unit and reduces the support effectiveness of energy supply to the grid [3] [4].…”

Section: Introductionmentioning

confidence: 99%

Investigation of Flow Characteristics of Flow Passage Components in Francis Turbine under No-load and 50% Load operating conditions

Zhang

et al. 2022

J. Phys.: Conf. Ser.

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Due to the varying demand of power grid for the electric supply of hydraulic power stations, the units are often under low-load operating condition and no-load standby state, causing a significant flow instability in hydraulic generator units. To further investigate the inside flow characteristics of hydraulic turbines under such operating conditions. In this study, a CFD (computational fluid dynamics) numerical simulation with applying RNG (Renorm alization Group) k-ε turbulence model is performed to study the inside flow characteristics of each flow passage components of a Francis turbine under no-load and 50% load conditions. The results indicate that under the two operating conditions, the flow distribution inside and outside the draft tube pier is significantly nonuniform. Simultaneously, the large-scale vortex in the runner area caused by the high-speed flow in the vane-free area with small opening and the nonuniform flow velocity distribution in the straight cone section of the draft tube are the main reasons for the increase of hydraulic loss and the decrease of efficiency.

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“…During the last 15 years, several improvements have been achieved in the development of URANS and hybrid RANS/LES models [33][34][35]. Consequently, the present paper focuses on the influence of some "advanced" URANS turbulence models regarding the dynamics of the flow at the SNL operating condition of a high head Francis turbine already investigating at part load by Müller et al [36] and at various operating points by the current authors [37][38][39].…”

Section: Introductionmentioning

confidence: 99%

“…Evidence of harmful structural loading of the turbine runner blades during the normal start-up and shut-down procedures. Signals recorded with the onboard instrumentation[37].…”

mentioning

confidence: 99%

CFD Investigation of a High Head Francis Turbine at Speed No-Load Using Advanced URANS Models

Decaix

Hasmatuchi

Titzschkau³

et al. 2018

Applied Sciences

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Due to the integration of new renewable energies, the electrical grid undergoes instabilities. Hydroelectric power plants are key players for grid control thanks to pumped storage power plants. However, this objective requires extending the operating range of the machines and increasing the number of start-up, stand-by, and shut-down procedures, which reduces the lifespan of the machines. CFD based on standard URANS turbulence modeling is currently able to predict accurately the performances of the hydraulic turbines for operating points close to the Best Efficiency Point (BEP). However, far from the BEP, the standard URANS approach is less efficient to capture the dynamics of 3D flows. The current study focuses on a hydraulic turbine, which has been investigated at the BEP and at the Speed-No-Load (SNL) operating conditions. Several “advanced” URANS models such as the Scale-Adaptive Simulation (SAS) SST k - ω and the BSL- EARSM have been considered and compared with the SST k - ω model. The main conclusion of this study is that, at the SNL operating condition, the prediction of the topology and the dynamics of the flow on the suction side of the runner blade channels close to the trailing edge are influenced by the turbulence model.

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Experimental and numerical investigations of a high-head pumped-storage power plant at speed no-load.

Cited by 7 publications

References 5 publications

On-board measurements at a 100 MW high-head Francis turbine

On-board measurements at a 100 MW high-head Francis turbine

Investigation of Flow Characteristics of Flow Passage Components in Francis Turbine under No-load and 50% Load operating conditions

CFD Investigation of a High Head Francis Turbine at Speed No-Load Using Advanced URANS Models

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