Numerical Simulation of Cavitation Phenomena in a Centrifugal Pump

2009 ◽  
Author(s):  
Freddy Jeanty ◽  
Jesu´s De Andrade ◽  
Miguel Asuaje ◽  
Frank Kenyery ◽  
Auristela Va´squez ◽  
...  
Keyword(s):  
Experimental Data ◽  
Centrifugal Pump ◽  
Cfd Simulation ◽  
Common Phenomenon ◽  
Performance Parameters ◽  
Centrifugal Pumps ◽  
Cavitation Model ◽  
Cfd Simulations ◽  
Global Performance ◽  
Good Agreement

Cavitation is a common phenomenon that appears during the operation of the hydraulic turbomachines reducing performance and life of Centrifugal pumps. The main goal of this work is primarily a CFD-simulation of the whole Centrifugal Pump-Turbine including the suction cone, impeller, diffuser blades and volute, in order to characterize and evaluate its performance under cavitation conditions. The CFD simulations results were compared with experimental data under cavitation and non-cavitation conditions. A good agreement has been obtained under non-cavitation conditions for global performance parameters. After the implementation of the Rayleigh Plesset cavitation model, the required Net Positive Suction Head (NPSHr) has been predicted from CFD simulations. Finally, a full cavitation test can be reproduced for a Hydraulic Turbomachine to avoid this dangerous phenomenon.

Influence of Jordanian zeolite on the performance of a solar still: experiments and CFD simulation studies

2016 ◽  
Vol 16 (6) ◽  
pp. 1700-1709 ◽  
Author(s):  
Yazan Taamneh
Keyword(s):  
Experimental Data ◽  
Phase Change ◽  
Cfd Simulation ◽  
Volume Fraction ◽  
Solar Still ◽  
Cfd Simulations ◽  
Two Phase ◽  
Vof Model ◽  
Computational Fluid Dynamics Cfd ◽  
Good Agreement

Computational fluid dynamics (CFD) simulations were performed for experiments carried out with two identical pyramid-shaped solar stills. One was filled with Jordanian zeolite-seawater and the second was filled with seawater only. This work is focused on CFD analysis validation with experimental data conducted using a model of phase change interaction (evaporation-condensation model) inside the solar still. A volume-of-fluid (VOF) model was used to simulate the inter phase change through evaporation-condensation between zeolite-water and water vapor inside the two solar stills. The effect of the volume fraction of the zeolite particles (0 ≤ ϕ ≤ 0.05) on the heat and distillate yield inside the solar still was investigated. Based on the CFD simulation results, the hourly quantity of freshwater showed a good agreement with the corresponding experimental data. The present study has established the utility of using the VOF two phase flow model to provide a reasonable solution to the complicated inter phase mass transfer in a solar still.

Improvement of Cavitation Surge in a Double Suction Centrifugal Pump by Use of CFD

2017 ◽  
Author(s):  
Shusaku Kagawa ◽  
Naoki Matsushita
Keyword(s):  
Centrifugal Pump ◽  
Cfd Simulation ◽  
Reverse Flow ◽  
Low Frequency ◽  
The Other ◽  
Computational Time ◽  
Complete Suppression ◽  
Cavitation Model ◽  
Cfd Simulations ◽  
Pump Impeller

This paper discussed about suppressions of cavitation surge in a double suction centrifugal pump. In order to suppress the cavitation surge, CFD simulation was carried out. Cavitation surge was observed near the best efficiency point, and it was difficulty to operate the pump stably. The specific speed of the tested pump was about 81 [m3/min, min−1, m] or 533 [ft., USGPM, min.−1]. In general, the main cause of the cavitation surge is inlet reverse flows at the impeller inlet. In order to prevent the inlet reverse flow, two kinds of modification at the impeller inlet were applied. One was the reduction of impeller inlet area by using a suction ring, and the other was the reduction of impeller inlet diameter. To reduce the computational time, in CFD model, a half of the double suction centrifugal pump was modeled. CFD simulations were carried out using ANSYS CFX with the Rayleigh Preset cavitation model. It was confirmed that the head fluctuation caused by the cavitation phenomena was predicted qualitatively by use of unsteady CFD simulation in the original pump impeller. The head fluctuation was about the 16% of the time averaged head and the very low frequency was confirmed by the FFT analysis. In addition, the relationship between head characteristics and cavitation behavior was observed clearly. The objective of the suction ring was to eliminate the head fluctuations caused by the cavitation. It was concluded that the suction ring was very effective to prevent the cavitation surge. On the other hand, the decrease of impeller inlet diameter was effective to reduce the head fluctuations, which became half of that for the original pump impeller. As a result, it was suggested that the complete suppression of the cavitation surge by the reduction of impeller inlet diameter was difficult in this case. It was concluded that unsteady CFD simulations with cavitation model is very effective for clarification of the impeller inlet modification on the cavitation surge.

scholarly journals CFD Simulation of an Industrial Spiral Refrigeration System

Energies ◽  
2019 ◽  
Vol 12 (17) ◽  
pp. 3358
Author(s):  
A. Khenien ◽  
A. Benattayallah ◽  
G. Tabor
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Cfd Simulation ◽  
Regulatory Requirements ◽  
Cfd Simulations ◽  
Conduction Model ◽  
Cfd Models ◽  
Heating And Cooling ◽  
Mri Scans ◽  
Good Agreement

In the food industry, heating and cooling are key processes where CFD can play an important role in improving quality, productivity and reducing energy costs. Cooling products after baking is crucial for storage and transportation; the product has to be cooled efficiently to a specified temperature (often to fulfill regulatory requirements) whilst preserving its quality. This study involves the analysis of spiral cooling refrigerators used in cooling food products, in this case, Cornish Pasties. Three separate sets of CFD models were developed and validated against experimental data taken in the laboratory and measurements taken in use in industry. In the first set of models a full CFD model was developed of a refrigeration spiral including the pasties, and used to study the heat transfer from the products to the air. Further simulations were carried out on individual pasties to explore the pasty cooling and heat transfer to the air in more detail, with the pasty geometry being determined from MRI scans. In the final set of simulations, Image Based Meshing (IBM) was used to determine the interior structure of the pasty and develop a full heat conduction model of the interior, which was compared with separate laboratory experiments using jets of cold air to cool the pasty. In all cases, good agreement was obtained between the CFD results and experimental data, whilst the CFD simulations provide valuable information about the air flows and cooling in the industrial system.

Configuration Pump Performance Test System Design Based on Kingview

2011 ◽  
Vol 121-126 ◽  
pp. 3195-3199
Author(s):  
Li Feng Yang ◽  
Jun Yuan ◽  
Wei Na Liu ◽  
Xiu Ming Nie ◽  
Xue Liang Pei
Keyword(s):  
Experimental Data ◽  
Data Processing ◽  
System Design ◽  
Centrifugal Pump ◽  
Performance Test ◽  
Test System ◽  
Performance Parameters ◽  
Time Data ◽  
Pump Performance ◽  
Real Time Data

Use Kingview to acquire and display the centrifugal pump performance parameters for the real-time data, and will stored the collected experimental data in Access databases, using VB database read, and drawing function for the data processing and rendering performance parameters of relationship curves.

Study on the Reduction of Pressure Fluctuation for a Double-Suction Centrifugal Pump With Staggered Blades

2018 ◽  
Author(s):  
Qian-qian Li ◽  
Da-zhuan Wu
Keyword(s):  
Centrifugal Pump ◽  
Pressure Fluctuation ◽  
Cfd Simulation ◽  
Stokes Equations ◽  
Low Noise ◽  
Living Environment ◽  
Centrifugal Impeller ◽  
Fluctuation Analysis ◽  
Centrifugal Pumps ◽  
Vibration Performance

Due to the distinctive characteristic of massive flow rates, double-suction centrifugal pump has been extensively applied in lots of perspectives, such as drainage, irrigation, transportation projects and other hydraulic engineering realms. Nevertheless, the significance of the pressure fluctuation inside the double-suction centrifugal pump, which is getting more and more prominent under the soaring demands for low noise and comfortable living environment, could not be underestimated. Consequently, how to reduce the pressure fluctuation as far as possible and enhance the running stability of the pump is always the research hotspot. In this study, the double-suction centrifugal impeller with abominable vibration performance is redesigned to improve the internal flow and reduce the flow-induced noise. What’s addition, the two redesigned impellers wearing splitter blades were compared in staggered arrangement with different angles for the purpose of ulteriorly decreasing the pressure fluctuation. On the basis of Realizable k-ε model and SIMPLEC algorithm, the unsteady Reynolds-averaged Navier-Stokes equations (URANS) were resolved by means of CFD simulation and the flow performance and the vibration performance were validated with the experiments. The results illustrate that the redesigned impeller with multi-blade could raise the hydraulic performance and reduce the pressure fluctuation inside the pump. When the impeller of each side was laid with the staggered angle of 12 degrees, the pressure distribution tended to be more uniform and the pressure fluctuation was well ameliorated. Through the pressure fluctuation analysis in time domain and frequency domain, the pressure change inside the pumps could be evaluated quantitatively and accurately, hence different pumps could be contrasted in detail. The consequences of this paper could provide reference for pressure fluctuation reduction and vibration performance reinforcement of double-suction centrifugal pumps as well as other vane pumps.

Evaluate a New Pump Design Using CFD Simulation

2019 ◽  
Author(s):  
Hui Ding ◽  
Benjamin Greenfield
Keyword(s):  
Centrifugal Pump ◽  
Cfd Simulation ◽  
Cfd Simulations ◽  
Pump Design ◽  
Pump Performance ◽  
Simulation Techniques ◽  
Overall Performance ◽  
Design Software ◽  
Simulation Results ◽  
Pump Assembly

Abstract This paper describes how CFD simulations were used to help evaluating a centrifugal pump performance. The simulated pump was designed totally from scratch. Many aspects of pump performance characteristics were predicted based on the geometry generated using a pump design software. Especially the effects of the free spin of the 3rd rotor in a 3 stage pump assembly on overall performance were evaluated. Pump models, simulation techniques, and simulation approaches will be presented in detail. Simulation results will be discussed and compared with available test data.

CFD Simulation of Slug Dissipation in an Enlarged Impacting Tee

2019 ◽  
Author(s):  
Mobina Mohammadikharkeshi ◽  
Mazdak Parsi ◽  
Ramin Dabirian ◽  
Ram S. Mohan ◽  
Ovadia Shoham
Keyword(s):  
Experimental Data ◽  
Void Fraction ◽  
Cfd Simulation ◽  
Petroleum Industry ◽  
Production Operation ◽  
Cfd Simulations ◽  
Ansys Fluent ◽  
Transient Model ◽  
Diameter Pipe ◽  
Computational Fluid Dynamics Cfd

Abstract Slug flow, which commonly occurs in the petroleum industry, is not always a desired flow pattern due to production operation problems it may cause in pipelines and processing facilities. To mitigate these problems, flow conditioning devices such as multiphase flow manifolds and slug catchers are used, where dissipation of slugs occurs in downward flow or in larger diameter pipe sections. Tee-junctions are important parts of these flow conditioning devices. In this work, Computational Fluid Dynamics (CFD) simulations are conducted using ANSYS/FLUENT 17.2 to investigate slug dissipation in an Enlarged Impacting Tee-Junction (EIT). An Eulerian–Eulerian MultiFluid VOF transient model in conjunction with the standard k-ε turbulent model is used to simulate slug dissipation in an EIT geometry. The EIT consists of a 0.05 m ID 10 m long inlet, which is connected to the center of a 0.074 m ID 5.5 m long section that forms the EIT branches. Moreover, experimental data are acquired on slug dissipation lengths in a horizontal EIT with a similar geometry as in the CFD simulations. The CFD results include the mean void fraction and cross-sectionally averaged void fraction time series in the EIT for different gas and liquid velocities. These results provide the inlet slug length and dissipation length in the EIT branches. The CFD results are evaluated against the experimental data demonstrating that the slug dissipation occurring in EIT branches can be predicted by simulation.

Comparison of Transport Equation-Based Cavitation Models and Application to Industrial Pumps with Inducers

2021 ◽  
Author(s):  
Enver Karakas ◽  
Nehir Tokgoz ◽  
Hiroyoshi Watanabe ◽  
Matteo Aureli ◽  
Cahit Evrensel
Keyword(s):  
Transport Equation ◽  
Centrifugal Pump ◽  
Experimental Results ◽  
Vaporization Rate ◽  
Centrifugal Pumps ◽  
Cavitation Model ◽  
Cavitation Performance ◽  
High Dependency ◽  
The Impact ◽  
Empirical Constants

Abstract This paper investigates and compares four commonly used flow transport equation-based cavitation models and their applicability to predict the cavitation performance and bubble dynamics of an industrial centrifugal pump with a helical inducer. The main purpose of this study is to identify the most appropriate cavitation model and the associated empirical constants for calculating the cavitation performance of centrifugal pumps with inducers. Each cavitation model is reviewed in detail and the uniqueness of each model is outlined. These cavitation models are incorporated in a computational fluid dynamics code to study the vaporization and condensation transport rate of the fluid. Experimental tests are conducted on the pump to determine the true cavitation performance in terms of Net Positive Suction Head (NPSH). Experimental results are compared to simulation results for different cavitation models to validate accuracy and assumptions of each model, along with the empirical constants. Lastly, bubble formation, cavitation inception, and bubble growth predicted by each cavitation model are compared with the experimental results. A sensitivity analysis is conducted in order to determine the impact of each set of empirical constants to the condensation and the vaporization rate in the centrifugal pump. Results show that two of the cavitation models exhibit high dependency on the empirical constants in terms of change in vaporization rate. Modifications to empirical constants for two of the four cavitation models are suggested to obtain agreement with the experimentally observed cavitation behavior and better predict NPSH performance for the industrial pump studied.

Experimental and Numerical Investigation of Stationary Ribbed Ducts

2004 ◽  
Author(s):  
A. Magi ◽  
F. Montomoli ◽  
P. Adami ◽  
C. Carcasci
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Cfd Simulation ◽  
Low Cost ◽  
Turbulence Models ◽  
Data Set ◽  
Contour Maps ◽  
Accuracy Level ◽  
Coolant System ◽  
Good Agreement

Goal of this work is to define the main issues and guidelines for an accurate heat transfer CFD simulation of internal ribbed ducts. To this aim, two different ribbed ducts (AR = 1,3) have been experimentally investigated to obtain a data set useful to validate numerical analyses. Experimental HTC contour maps have been obtained using unsteady TLC technique. CFD activity deals with numerical simulation using both a commercial (Star-CD™) and an “in house” solver (HybFlow). Four different variants of the well-known two-equation turbulence models have been considered. Low cost heat transfer predictions of internal ducts are highly demanded by industry despite the uncommon complexity of modern internal coolant system. Accordingly, the main aim of the work is to provide some indications for the numerical modelling and to evaluate the accuracy level of predicted heat transfer when commercial or research packages are employed along with different grid resolution levels. Overall results are in good agreement with experimental data even if some local discrepancies are present.

Sign in / Sign up

Export Citation Format

Share Document