Experimental Investigations Concerning Erosive Aggressiveness of Cavitation at Different Test Configurations

Bachert, Bernd; Dular, Matevž; Baumgarten, Sebastian; Ludwig, G.; Stoffel, B.

doi:10.1115/ht-fed2004-56597

Cited by 5 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, the experimental cavitation numbers are higher for the higher velocities than those in the numerical model, which implies higher environment pressures and higher collapse efficiencies for higher velocities. Consequently, the erosion rate may increase with an exponent higher than 5, which would be in agreement with the experimental investigations by Dular et al, [40,41] who found that the erosion damage followed a power law with n values from 5 to 8.…”

Section: Appl Sci 2020 10 X For Peer Review 20 Of 23supporting

confidence: 91%

Numerical Simulation of Cavitation Erosion Aggressiveness Induced by Unsteady Cloud Cavitation

et al. 2020

View full text Add to dashboard Cite

A numerical investigation of the erosion aggressiveness of leading edge unsteady cloud cavitation based on the energy balance approach has been carried out to ascertain the main damaging mechanisms and the influence of the free stream flow velocity. A systematic approach has permitted the determination of the influence of several parameters on the spatial and temporal distribution of the erosion results comprising the selection of the cavitation model and the collapse driving pressure. In particular, the Zwart, Sauer and Kunz cavitation models have been compared as well as the use of instantaneous versus average pressure values. The numerical results have been compared against a series of experimental results obtained from pitting tests on copper and stainless steel specimens. Several cavitation erosion indicators have been defined and their accuracy to predict the experimental observations has been assessed and confirmed when using a material-dependent damaging threshold level. In summary, the use of the average pressure levels during a sufficient number of simulated shedding cycles combined with the Sauer cavitation model are the recommended parameters to achieve reliable results that reproduce the main erosion mechanisms found in cloud cavitation. Moreover, the proposed erosion indicators follow a power law as a function of the free stream flow velocity with exponents ranging from 3 to 5 depending on their definition.

show abstract

Section: Appl Sci 2020 10 X For Peer Review 20 Of 23supporting

confidence: 91%

Numerical Simulation of Cavitation Erosion Aggressiveness Induced by Unsteady Cloud Cavitation

et al. 2020

View full text Add to dashboard Cite

show abstract

“…18 Although the external characteristics of centrifugal pump do not change greatly at the initial stage of cavitation, cavitation will still cause pitting on the surface of impeller blade. 19 The significance of cavitation status monitoring is to determine the position of cavitation inception point as accurately as possible to avoid the operation of centrifugal pump in the quasi steady cavitation stage.…”

Section: Numerical Calculation Results and Analysismentioning

confidence: 99%

Numerical study on cavitation flow and induced pressure fluctuation characteristics of centrifugal pump

Zhang

Dong

2023

Proceedings of the Institution of Mechanical Engineers, Part A:

View full text Add to dashboard Cite

In order to reveal the variation law between cavitation process and pressure pulsation characteristics of centrifugal pump, the internal flow characteristics and pressure pulsation characteristics of centrifugal pump during cavitation development are studied in this paper. First, select the standard k- ε with good coincidence between external characteristics and test data under rated conditions model for calculation after compare the standard k- ε, RNG k- ε and SST k- ω. Then, based on the unsteady calculation results, the characteristics of the internal flow before and after the cavitation critical point, the frequency domain characteristics of the pressure pulsation on the volute wall and at the impeller inlet monitoring points in different cavitation stages are compared and analyzed. Finally, root mean square (RMS) is used to study the change trend of pressure fluctuation energy intensity with cavitation process. The research results show that the prediction accuracy of the characteristic points of RMS change curve of pressure fluctuation for cavitation is higher than that of the traditional 3% head drop point. Using the energy characteristics of pressure fluctuation can more accurately and timely determine the occurrence of cavitation.

show abstract

“…(1) Incipient Stage: In this stage, cavitation bubbles form and collapse in the blade inlet region, causing pitting damage to the blade [11].…”

Section: Cavitation Mechanismmentioning

confidence: 99%

“…(2) Weak Cavitation Stage: This stage encompasses the development of cavitation from its incipient state to the point of unstable cavitation occurrence [12]. Prolonged operation in a state of weak cavitation leads to surface damage in the overflow components, with the damage initiating on the blade inlet side and correlating with the length of the cavitation hole [11]. The scope of the weak cavitation stage can be determined through the analysis of the non-stationary dynamic properties.…”

Section: Cavitation Mechanismmentioning

confidence: 99%

“…Water 2024, 16, x FOR PEER REVIEW 3 of 33 (1) Incipient Stage: In this stage, cavitation bubbles form and collapse in the blade inlet region, causing pitting damage to the blade [11]. (2) Weak Cavitation Stage: This stage encompasses the development of cavitation from its incipient state to the point of unstable cavitation occurrence [12].…”

Section: Cavitation Mechanismmentioning

confidence: 99%

See 1 more Smart Citation

Research Progress on Identification and Suppression Methods for Monitoring the Cavitation State of Centrifugal Pumps

Zhu,

Zhou,

et al. 2023

Water

View full text Add to dashboard Cite

Cavitation is a detrimental phenomenon in hydraulic machinery, adversely impacting its performance, inducing vibration and noise, and leading to corrosion damage of overflow components. Centrifugal pump internal cavitation will lead to severe vibration and noise, and not only will the performance of hydraulic machinery be adversely affected but the impact generated by the collapse of the vacuole will also cause damage to the impeller wall structure, seriously affecting the safety of the equipment’s operation. To prevent the generation and development of internal cavitation in centrifugal pumps, to prevent the hydraulic machinery from being in a state of cavitation for a long time, to avoid the failure of the unit, and to realize the predictive maintenance of centrifugal pumps, therefore, it is of great significance to research the methods for monitoring the cavitation of hydraulic machinery and the methods for suppressing the cavitation. This paper comprehensively describes the centrifugal pump cavitation mechanism and associated hazards. It also discusses the current state of centrifugal pump cavitation monitoring methods, including commonly used approaches such as the flow-head method, high-speed photography, pressure pulsation method, acoustic emission method, and vibration method. A comparative analysis of these methods is presented. Additionally, the paper explores signal characterization methods for centrifugal pump cavitation, including time-domain feature extraction, frequency-domain feature extraction, and time–frequency-domain feature extraction. The current research status is elaborated upon. Moreover, the paper presents methods to mitigate cavitation and prevent its occurrence. Finally, it summarizes the ongoing research on identifying and determining the cavitation state in centrifugal pumps and offers insights into future research directions.

show abstract

Experimental Investigations Concerning Erosive Aggressiveness of Cavitation at Different Test Configurations

Cited by 5 publications

References 0 publications

Numerical Simulation of Cavitation Erosion Aggressiveness Induced by Unsteady Cloud Cavitation

Numerical Simulation of Cavitation Erosion Aggressiveness Induced by Unsteady Cloud Cavitation

Numerical study on cavitation flow and induced pressure fluctuation characteristics of centrifugal pump

Research Progress on Identification and Suppression Methods for Monitoring the Cavitation State of Centrifugal Pumps

Contact Info

Product

Resources

About