Time–frequency characterization of the unsteady phenomena in a centrifugal pump

Pavesi, Giorgio; Cavazzini, Giovanna; Ardizzon, Guido

doi:10.1016/j.ijheatfluidflow.2008.06.008

Cited by 75 publications

(44 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Pavesi et al [2008] and the details of wake transport across the rotor were tracked in 56 continuously running facilities thanks to laser techniques (Akin et al, 1994, Eisele et al, 1997 2004, Feng et al ,2007, Benra et al, 2008, Wuibaut et al, 2000, 2006 [Culver et al, 2009, Petit et al, 2013 2002]…”

mentioning

confidence: 99%

Comparisons RANS and URANS numerical results with experiments in a vaned diffuser of a centrifugal pump

et al. 2015

View full text Add to dashboard Cite

show abstract

mentioning

confidence: 99%

Comparisons RANS and URANS numerical results with experiments in a vaned diffuser of a centrifugal pump

et al. 2015

View full text Add to dashboard Cite

show abstract

“…So each impeller revolution will be calculated in a time sequence of 360 time steps. Unsteady convergence also has a great influence on the achieved results, and at least forty revolutions were achieved to guarantee numerical accuracy [15]. Fast Fourier transform (FFT) method was adopted to change time domain signals into frequency domain signals to analyze pressure spectrums under different operating conditions.…”

Section: Turbulent Modelmentioning

confidence: 99%

Unsteady Pressure Pulsation and Rotating Stall Characteristics in a Centrifugal Pump with Slope Volute

Zhang

Yang

Gao

et al. 2014

Advances in Mechanical Engineering

View full text Add to dashboard Cite

Unsteady flow structures can lead to severe vibration in centrifugal pump if the eigenfrequency of the rotor is equal to excitation frequency. In order to reduce rotor-stator interaction in centrifugal pump, a special slope volute was proposed. This paper explores the use of numerical simulation method to illustrate unsteady pressure pulsation and rotating stall characteristics under 0.05Φ -1.4Φ working conditions. Spectrums of pressure pulsation signals at different flow rates were analyzed. Relative velocity distributions interior blade channels were also studied to clarify correlation between flow structure and pressure spectrum. At high flow rates, predominant components in pressure spectrums always correspond to blade passing frequency ( BPF ). With decreasing of flow rate, partial flow separates from suction side of blade at 0.6Φ , but the separate structure has little impact on pressure spectrum. From 0.8Φ to 0.6Φ , peak values in pressure spectrums are still located at BPF . At rotating stall working conditions, multiple vortex structures exist in impeller, which develop with rotating impeller showing intensive unsteady properties. And partial blade channels are blocked severely. Due to the unsteady stall cell structure, stall frequencies are generated in pressure spectrum, and the excitation frequencies are different at variable flow rates.

show abstract

“…Many numerical and experimental investigations on the unsteady flow that are rotor-stator interaction and rotating stall have been carried out on pump-turbine at pump mode and turbine mode at the constant flow rate [2][3][4][5][6][7]. In terms of research on the transient process, the transient processes that are runaway, no-load, load rejection and so on are studied in pump turbine at turbine mode by numerical simulation and experimental methods.…”

Section: Introductionmentioning

confidence: 99%

“…The transient instable flow including the flow separation, back flow and rotating stalls can cause severe pressure fluctuations, resulting in the vibrations of pump-turbine, even reducing the operating life expectancy and accidents. Thus, it is very important and urgent to investigate the transient flow mechanism for reducing the unstable flow [1].Many numerical and experimental investigations on the unsteady flow that are rotor-stator interaction and rotating stall have been carried out on pump-turbine at pump mode and turbine mode at the constant flow rate [2][3][4][5][6][7]. In terms of research on the transient process, the transient processes that are runaway, no-load, load rejection and so on are studied in pump turbine at turbine mode by numerical simulation and experimental methods.…”

mentioning

confidence: 99%

Numerical investigation on transient flow of a high head pump-turbine in pump mode during rapid closure of guide vanes

Pavesi

Wang

2017

European Conference on Turbomachinery Fluid Dynamics and Hermodynamics

View full text Add to dashboard Cite

Transient flow in pump turbines appears because the hydropower storage plant needs to experience variable operation modes to make a balance between the electricity production and consumption, thus causing high-pressure fluctuations and shortening life expectancy. In this paper, three-dimensional numerical simulation, based on Detached Eddy Simulation (DES) turbulent model, was carried out to investigate the flow characteristics in a high head pump turbine in pump mode during rapid closure of wicket gates. The dynamic mesh technique was applied to simulate the rotation of the guide vane. In this work, the influence of water compressibility on pressure fluctuations was considered. The transient flow characteristics during load reduction were investigated by time-frequency analysis methods of the numerical data. KEYWORDS IntroductionLast decades have witnessed an increasing consumption of renewable energy due to the increasing price of fossil fuels and damage of carbon dioxide emissions on the living environment. The development of wind energy, solar power energy, hydropower energy and clean energy has been put into investigation for many years. However, it is a challenging task to control the stability of the output of renewable energy transmitted to the electricity grid because of stochastic nature of the renewable energy and fluctuating requirement of customers.In the renewable energy system, hydropower pump storage plant has been deemed as a costeffective electricity storage technology to balance the output of renewable electricity and need of the customers. Even though hydropower pump storage plants has such advantage, it needs change the operation modes between the pump mode and turbine mode frequently to meet the unpredictable need of electricity consumption, leading to transient instable flow in the pump-turbine under variable transient processes including the start-up, stop and adjusting rotating speed and so on. Besides, one of the common transient processes is that the wicket gates are required to open or close frequently. The transient instable flow including the flow separation, back flow and rotating stalls can cause severe pressure fluctuations, resulting in the vibrations of pump-turbine, even reducing the operating life expectancy and accidents. Thus, it is very important and urgent to investigate the transient flow mechanism for reducing the unstable flow [1].Many numerical and experimental investigations on the unsteady flow that are rotor-stator interaction and rotating stall have been carried out on pump-turbine at pump mode and turbine mode at the constant flow rate [2][3][4][5][6][7]. In terms of research on the transient process, the transient processes that are runaway, no-load, load rejection and so on are studied in pump turbine at turbine mode by numerical simulation and experimental methods. Cavazzini et al [8] simulated the transient flow in pump turbine at turbine mode under no-load condition. She pointed out that the head began to increase due to the fully developed rotating...

show abstract

Time–frequency characterization of the unsteady phenomena in a centrifugal pump

Cited by 75 publications

References 15 publications

Comparisons RANS and URANS numerical results with experiments in a vaned diffuser of a centrifugal pump

Comparisons RANS and URANS numerical results with experiments in a vaned diffuser of a centrifugal pump

Unsteady Pressure Pulsation and Rotating Stall Characteristics in a Centrifugal Pump with Slope Volute

Numerical investigation on transient flow of a high head pump-turbine in pump mode during rapid closure of guide vanes

Contact Info

Product

Resources

About