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The purpose of the paper is to predict the erosion rate of the components of centrifugal pump under certain operating condition to identify the maximum erosion area and to discuss the factors affecting them. This helps to optimize design and estimate service life.

In the paper, the Eulerian–Lagrangian approach method coupled with the erosion model to investigate the mixed sand characteristics on erosion characteristics of centrifugal pump flow-through wall. The hydraulic performance and wear characteristics experiment of the pump is used to verify the accuracy of the numerical simulation.

The blade erosion area mainly occurs near the blade inlet and the trailing edge of the pressure surface, the main erosion area of the impeller back shroud is near the outlet of the flow passage and the main erosion area of the volute is near the tongue and the I section. With the change of the average diameter and density of sand particles, the average erosion rate on different flow-through walls is positively correlated with the average mass concentration to a certain extent. However, for different sand shape factors, there is little correlation between the average erosion rate and the average mass concentration. In addition, compared with other erosion areas, the increase of average sand particle diameter and density has the greatest impact on the total erosion rate of blade pressure surface, while the shape of sand particles has a greater impact on the total erosion rate of each flow-through wall of centrifugal pump.

In this work, according to the characteristics of the mixed distribution of different sand diameters in the Yellow River Basin, the erosion characteristics of centrifugal pumps used in the Yellow River Basin are studied. The numerical calculation method for predicting the wall erosion of centrifugal pump is established and compared with the experimental results. The results can provide reference for optimizing design and increasing service life.

To analyze the work principle and capacity of energy conversion in each segment of profile lines, the energy transfer from impeller to transmission medium is separated into head coefficient and load coefficient to analyze the energy transfer process. The concepts of airfoil lift coefficient and drag coefficient are used; the third manifestation of the Euler equations is used as well.

The numerical simulation of energy conversion mechanism based on load criteria of vane airfoil has been established in screw centrifugal pump to explain its energy conversion mechanism in an impeller. Upon this basis, the velocity and pressure along the entire blade are investigated through the numerical simulation of internal solid–liquid flow in the pump. The energy conversion process under load criteria in the blade airfoil has also been obtained.

The research suggests that the mathematical model of energy conversion mechanism based on the load criteria of the vane airfoil is reliable in the screw centrifugal pump. The screw centrifugal blade has twice or even several times the wrap angle than the ordinary centrifugal blade. It is a large wrap angle that forms the unique flow channel which lays the foundation for solid particles to pass smoothly and for soft energy conversion. At the same time, load distribution along the profile line on the long-screw centrifugal blade is an important factor affecting the energy conversion efficiency of the impeller.

The quantitative analysis method of energy in the screw centrifugal pump can help the pump designer improve certain features of the pump and shorten the research cycle.

The purpose of this paper is to study the pressure fluctuation characteristics in the sidewall gaps of a centrifugal dredging pump in detail and discover the excitation sources.

An unsteady numerical simulation with shear–stress transport–scale-adaptive simulation (SAS-SST) model was conducted for a centrifugal pump considering the sidewall gaps. The numerical codes were validated by a model test carried out in China Water Resources Beifang Investigation, Design and Research Co., Ltd. Fast Fourier transform was used to obtain the frequency components of the pressure fluctuation.

Pressure fluctuation characteristics inside the pump were analyzed for a condition near the design point. In the sidewall gaps, the circumferential, radial and axial distribution of the pressure fluctuation amplitude follow different laws. The non-axisymmetrical distribution of pressure fluctuation in the sidewall gaps shows that the unsteady flow in the volute casing which has a non-axisymmetrical geometry imposes an evident effect on the flow field in the sidewall gaps and the interaction between the main flow and the clearance flow cannot be neglected. There are several frequency components appearing as the dominant frequencies at different locations in the sidewall gaps, but the relatively stronger pressure fluctuations are all dominated by the rotating frequency. It indicates that the rotating impeller, which originally makes the shrouds rotate, is the primarily excitation source of the pressure fluctuations in the sidewall gaps.

The pressure fluctuation characteristics in the sidewall gaps of centrifugal pumps were first comprehensively analyzed. Unsteady flows in the sidewall gaps should be considered during the design and operation of centrifugal pumps.

An approach is presented for the development of a predictive maintenance system for rotor‐dynamic pumps, which focuses on the diagnosis of abnormal events related to fluid‐dynamic operating conditions. This methodology is based on an experimental characterization of the dynamic response of the pump under different loads and operation anomalies. The procedure has been put into practice on a medium‐sized centrifugal pump. The results obtained show that a simple spectral analysis of the pressure signals captured at either the inlet or the outlet of the pump can provide sufficient decision criteria to constitute the basis for a diagnostic system. This was not true however when analyzing signals of acceleration at the pump casing.

The purpose of this paper is to illustrate the application of neural network approach to analyze machine's behaviour quantitatively.

The model is developed based on real plant‐data from a variable speed drive centrifugal type pump. The best model settings are recorded and tested for another similar unit in the vicinity to check its generalization capabilities. Owing to the absence of faulty data, this model is tested against preventive maintenance data that show symptoms of abnormality that are seemingly undetected in existing monitoring and control systems. The paper systematically summarizes published literature and suggests suitable network architecture and its capabilities by illustrative example from oil export pumps from an oil and gas offshore production facility.

Artificial intelligent techniques provide a robust platform in providing useful information about system health and sub‐optimal performance.

In any industry, unexpected equipment downtime in principal questions the overall technical integrity of the platform raising major economical concerns. In the Oil & Gas sector, production platforms are in a 24/7 run mode, and thus undergoing major re‐engineering processes by improving existing surveillance and control techniques of their asset. Machine degradation and abnormalities gradually affect performance and in some cases these are not visible in existing condition monitoring (CM) schemes. Recently, there has been an increasing demand for testing and implementing intelligent techniques as a subsidiary to existing CM programs to monitor and assess system's health. Artificial neural networks have emerged as one of the most promising technique in this regard.

The proposed methodology highlights how healthy data from a system can be effectively modelled to identify significant abnormalities. This paper will be useful for experts working in the area of maintenance engineering to early identify state of the system performance.

The centrifugal pump is one of the most widely used pieces of equipment found in industry. Despite this, an engineering student often completes his course of study with only the vaguest idea about the selection and performance of pumps of both the centrifugal and axial flow types.

The purpose of this paper is to analyze the cavitation dynamics in the blade channel of a centrifugal pump with a particular focus on the direct influence of the pump’s volute.

A homogeneous multiphase model, namely the Zwart-Gerber-Belamri cavitation model, is employed to numerically describe the evolution of the process of cavitation within the pump. The RNG k-e turbulence model is applied to analyze the unsteady turbulent flow. A second order implicit formulation is used for the time discretization for the unsteady flow calculation and a finite volume algorithm is used for the space discretization.

The cavities in the passage exhibit an obvious life cycle which includes initiation, growth, contraction, and separation, and collapse with a frequency corresponding to the impeller rotation frequency under off-design conditions. This phenomenon arises through an alternating interaction between reverse flow with the cavity interface and is associated with the response of the vortex region to the effect of uneven pressure distribution on volute and impeller-tongue interaction.

This study simulated and analyzed the complex transient cavitation flow patterns inside a centrifugal pump and explains the reason for the unsteadiness. This knowledge is instructive in achieving the stable operation of pumps and in trouble shooting rough or cavitating operation.

IN a paper to The Institute of Marine Engineers on 12th January, 1960, in London, T. McAlpine, B.Sc., M.I.Mar.E. (Chief Mechanical Engineer, G. & J. Weir Ltd.) and L. S. Paterson, B.Sc. (Chief Research and Development Engineer, Drysdalc & Co. Ltd.) discussed the important developments in pump design and pumping systems within the last fifteen years, with particular reference to marine services. The following is an extract from this paper dealing specifically with lubricating oil and engine cooling pumps for marine service.

Construct a new sub-grid scale (SGS) model which can improve the efficiency and maintain comparative accuracy comparing to the existing dynamic cubic non-linear SGS model (DCNM).

The polynomial constitutive relation between the SGS stress tensor and both strain and rotation rate is selected as a basement. Simplification is achieved by eliminating the solid-body rotation term and adopting the assumption proposed by Kosovic. A dynamic procedure is applied to calculate three model coefficients in the new model. The new model (named dynamic simplified Lund model) and DCNM are applied to the rotating channel flow and the internal flow in a centrifugal pump impeller to examine the performance.

The new model is as accurate as DCNM but decreases 25 per cent computational resources. The ability of capturing rotation effect and reflecting backscatter is verified through cases. In addition, good numerical stability is shown during the calculation.

More benchmark and engineering cases should be used to get further confidence on the new model.

The new model is promising in industrial application with the advantage of both accuracy and efficiency. For the flow with large-scale separation or more complicate phenomenon, the model is thought to give accurate flow structure.

A new non-linear SGS model is proposed in this paper. The accuracy, numerical stability and efficiency are validated for this model. Therefore, it is promising in the prediction of the flow structure in centrifugal pumps.

The purpose of the paper is numerical simulation and experimental analysis of a cavitation operating regime in a centrifugal water pump. The main goal is to extend the mathematical model to be able to predict the phenomena where thermodynamic process is controlled by an hydrodynamic flow pattern.

The mathematical model is being extended and used for numerical simulation of an unstable operating regime in a water pump. Numerical simulation results were compared to thermal imaging system visualisation and flow variables measurements results.

The presented approach increases the system stability. The model can be used for simulation of system instabilities that involve not just the pump characteristics but those of the complete piping system. Modified turbulence model including compressibility effects lead to reliable simulation results of pump unsteady cavitation behaviour.

The research was limited to an homogenous cavitation transport model based on the additional transport equation approach. The validation results are connected to a single commercial radial water pump geometry and the numerical domain size is limited by computer capability.

The work extends the application of an homogenous cavitation model to the complicated flow regime using advanced turbulence modelling. The re‐entrant jet behaviour in a rotating pump is modelled successfully. The work adds the value of numerical simulation models to engineering problems in fluid machinery.