Investigation of Centrifugal Pump Performance Under Two-Phase Flow Conditions

1995 ◽  
Vol 117 (1) ◽  
pp. 129-137 ◽  
Author(s):  
G. R. Noghrehkar ◽  
M. Kawaji ◽  
A. M. C. Chan ◽  
H. Nakamura ◽  
Y. Kukita
Keyword(s):  
Centrifugal Pump ◽  
Nuclear Reactor ◽  
Two Phase Flow ◽  
Fluid Model ◽  
Small Scale ◽  
Phase Flow ◽  
Flow Conditions ◽  
Two Phase ◽  
Pump Impeller ◽  
Pump Head

A one-dimensional two-fluid model has been used to study the centrifugal pump head degradation phenomena and to analyze the gas-liquid interaction within the pump impeller under high pressure, steam-water two-phase flow conditions. The analytical model was used to predict the two-phase pump head data for the small-scale and full-scale nuclear reactor pumps and the predictions of the head degradation compared favorably with the test data for different suction void fractions. The physical mechanisms responsible for head degradation were also investigated.

Characterization of a centrifugal pump impeller under two-phase flow conditions

2008 ◽  
Vol 63 (1-4) ◽  
pp. 18-22 ◽  
Author(s):  
Jose Caridad ◽  
Miguel Asuaje ◽  
Frank Kenyery ◽  
Andrés Tremante ◽  
Orlando Aguillón
Keyword(s):  
Centrifugal Pump ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Flow Conditions ◽  
Two Phase ◽  
Pump Impeller ◽  
Centrifugal Pump Impeller

Numerical Simulation of the Two-Phase Flow in Centrifugal Pump Impellers

2002 ◽  
Author(s):  
Rudolf Schilling ◽  
Moritz Frobenius
Keyword(s):  
Centrifugal Pump ◽  
Two Phase Flow ◽  
Volume Fraction ◽  
Fluid Model ◽  
Numerical Procedure ◽  
Phase Flow ◽  
Two Phase ◽  
Simulation Tools ◽  
Total Wear ◽  
Small Volume Fraction

The numerical simulations of three types of two-phase flow in centrifugal pump impellers are described. First, the liquid-solid particle flow is modeled by an Euler-Lagrangeian approach assuming a mass concentration less than 5% and particle diameters being less than 1000 microns. The empirical erosion model to predict the local and total wear is calibrated by measurements. Second, the influence of the relative air contents on the head-drop is simulated assuming a relatively small volume fraction and applying a simple one-fluid model. The mixture is characterized by a common density depending on the flow field. Finally, the cavitating flow is studied by implementing the Rayleigh equation into the numerical procedure describing the transient process of bubble growth and collapse. The developed simulation tools are applied to predict the three types of two-phase flows in impellers. Within the defined ranges of application the simulation results agree fairly well with the experimental data.

Performance and pressure distribution changes in a centrifugal pump under two-phase flow

1998 ◽  
Vol 212 (3) ◽  
pp. 165-171 ◽  
Author(s):  
E T Pak ◽  
J C Lee
Keyword(s):  
Pressure Gradient ◽  
Pressure Distribution ◽  
Centrifugal Pump ◽  
Void Fraction ◽  
Two Phase Flow ◽  
Positive Pressure ◽  
Phase Flow ◽  
Flow Conditions ◽  
Two Phase ◽  
Pump Performance

Pump performance characteristics change drastically under two-phase flow conditions from those of single-phase flow. This is due to a change in flow characteristics in the impeller. Owing to a positive pressure gradient the air bubble moves more slowly than the water in the impeller channel, but in the suction surface region of the impeller inlet, where a negative pressure gradient prevails, the bubbles move more quickly than the water. Thus, in the space just after this region the distributions of the void fraction obtained are considerably higher and uneven. The change in the pressure distribution owing to air admission is also particularly evident in the inlet region of the impeller. These changes bring about an alteration of the whole flow pattern in the impeller and also cause a drop in pump performance. The Reynolds-averaged Navier-Stokes equations for two-phase flow in a centrifugal pump impeller are solved using a finite volume method to obtain the pressure, velocities and void fraction respectively. Good agreement is achieved when the predicted results are compared with those measured experimentally within the range of bubbly flow conditions.

scholarly journals Prediction of Gas-Liquid Two-Phase Flow Performance of a Centrifugal Pump Using a One-Dimensional, Two-Fluid Model

1997 ◽  
Vol 63 (611) ◽  
pp. 2377-2385
Author(s):  
Kiyoshi MINEMURA ◽  
Tomomi UCHIYAMA ◽  
Katsuhiko KINOSHITA ◽  
Lin LYU ◽  
Shinji SYODA ◽  
...  
Keyword(s):  
Centrifugal Pump ◽  
Two Phase Flow ◽  
Fluid Model ◽  
Phase Flow ◽  
Two Phase ◽  
One Dimensional ◽  
Two Fluid Model ◽  
Two Fluid

scholarly journals Investigation on the Handling Ability of Centrifugal Pumps under Air–Water Two-Phase Inflow: Model and Experimental Validation

Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 3048 ◽  
Author(s):  
Qiaorui Si ◽  
Gérard Bois ◽  
Qifeng Jiang ◽  
Wenting He ◽  
Asad Ali ◽  
...  
Keyword(s):  
Centrifugal Pump ◽  
Two Phase Flow ◽  
Bubbly Flow ◽  
Three Dimensional ◽  
Navier Stokes ◽  
Phase Flow ◽  
Centrifugal Pumps ◽  
Flow Conditions ◽  
Two Phase ◽  
Local Flow

The paper presents experimental and numerical investigations performed on a single stage, single-suction, horizontal-orientated centrifugal pump in air–water two-phase non-condensable flow conditions. Experimental measurements are performed in a centrifugal pump using pressure sensor devices in order to measure the wall static pressures at the inlet and outlet pump sections for different flow rates and rotational speeds combined with several air void fraction (a) values. Two different approaches are used in order to predict the pump performance degradations and perform comparisons with experiments for two-phase flow conditions: a one-dimensional two-phase bubbly flow model, and a full “Three-Dimensional Unsteady Reynolds Average Navier–Stokes” (3D-URANS) simulation using a modified k-epsilon turbulence model combined with the Euler–Euler inhomogeneous two-phase flow description. The overall and local flow features are presented and analyzed. Limitations concerning both approaches are pointed out according to some flow physical assumptions and measurement accuracies. Some additional suggestions are proposed in order to improve two-phase flow pump suction capabilities.

scholarly journals 1110 Limiting Streamline Observation of Air-water Two Phase Flow Centrifugal Pump Impeller by Oil Film Method

2009 ◽  
Vol 2009 (0) ◽  
pp. 361-362
Author(s):  
Toshio WATANABE ◽  
Kazuhiro SHITE ◽  
Satoshi WATANABE ◽  
Kusuo OKUMA ◽  
Akinori FURUKAWA
Keyword(s):  
Centrifugal Pump ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Two Phase ◽  
Pump Impeller ◽  
Oil Film ◽  
Film Method ◽  
Centrifugal Pump Impeller

Image Based Bubbly Flow Feature Identification Using Deep Learning

2021 ◽  
Author(s):  
Takashi Furuhashi ◽  
Takuro Sasaki ◽  
Shuichiro Miwa
Keyword(s):  
High Speed ◽  
Nuclear Reactor ◽  
Two Phase Flow ◽  
Fluid Model ◽  
Bubbly Flow ◽  
Interfacial Area ◽  
Liquid Interface ◽  
Phase Flow ◽  
Two Phase ◽  
Interfacial Area Concentration

Abstract Gas-liquid two-phase flow has high potential in heat transfer and mixing capabilities, and therefore it is utilized in various technologies such as nuclear reactor and chemical plants. There are several flow regimes since the gas-liquid interface transforms constantly. For the sake of safety and optimization in operating plants, it is crucial to understand the behavior of the gas-liquid interface. We have focused on extracting the bubble features in the bubbly flow by filming the bubbly flow with a high-speed camera and training convolutional neural network (CNN) for feature extraction. The assumption made was bubbles in the bubbly flow being ellipsoids. Since void fraction and interfacial area concentration are one of the geometric parameters in the two-phase flow models, like two-fluid model, it becomes possible to evaluate the flow field of the two-phase flow quickly and quantitively by calculating these parameters from the extracted features. We have compared two-phase flow parameters with the conventional object detection method using bounding boxes, and the new ellipse fitting method to identify the best region proposal shape. As a result, the conventional method showed higher accuracy in extracting bubble features under our flow conditions.

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