CFD Simulation of Flow Phenomena in Selected Centrifugal Pumps, Industrial Fans and Positive Displacement Pumps (original) (raw)

CFD Analysis Of Performace Charectristics Of Centrifugal Pump Impeller To Minimising Cavitation

—Design and development of turbo machines like centrifugal pump is highly complex due to turbulence flow structure, unsteadiness and cavitation inside the pump. The pump suffers with loss of efficiency, erosion of material, degradation of its useful life caused by cavitation. Computational Fluid Dynamics technique has been applied by the researchers to carry out different improvements on centrifugal pump in cavitational analysis, efficiency prediction. The analysis is done through various turbulence models in CFD to get accurate numerical results. Cavitation and its interaction to the impeller and volute of centrifugal pump appeared as the research field for further development of pump performance. The effects of cavitation in the performance of centrifugal pump is identified, the scope for further improvement presented in this paper. Certain number of parameters is derived from the literatures which may act as causes for cavitation in the centrifugal pump. They are analyses and obtained optimum value to reduce the effect of cavitation.

CFD Analysis for Cavitation of a Centrifugal Pump Impeller

2019

Centrifugal Pumps are the most common appliances used in various industries, agriculture and domestic application& thus its impeller design thus required a very precise understanding of the internal flow at rated and part load operating conditions. Design and development of turbo machines like centrifugal pump is highly complex due to turbulence flow structure, unsteadiness and cavitation inside the pump. The pump suffers with loss of efficiency, erosion of material, degradation of its useful life caused by cavitation. The Phenomenon of cavitation can be described as the vapor bubbles formation in an originally liquid flow, this change of phase is carried through at constant temperature and local drop pressure, generated by flow conditions. Turbo machines like centrifugal pumps suffer with loss of performance, degradation of its useful life caused by the cavitation. Under the analytical point of view the cavitation phenomenon shows very complex, bringing great physical and numerical...

CFD Analysis of Centrifugal Pump: A Review

The main objective of this work is to understand role of the computational fluid dynamics (CFD) technique in analyzing and predicting the performance of centrifugal pump. Computational Fluid Dynamics (CFD) is the present day state-of-art technique for fluid flow analysis. The critical review of CFD analysis of CFD analysis of centrifugal pump along with future scope for further improvement is presented in this paper. Different solver like ANSYS-CFX, FLUENT etc can be used for simulations. Shear stress transport model has been found appropriate as turbulence model. Study of pressure contours, velocity contours, flow streamlines etc can be studied by CFD techniques. Unsteady Reynolds Averaged Navier Stokes (URANS) equations are solved by solver to get flow simulation results inside centrifugal pump. CFD results has to be validated with testing results or with performance characteristics curves. Performance prediction at design and off-design conditions, parametric study, cavitation analysis, diffuser pump analysis, performance of pump running in turbine mode etc. are possible with CFD simulation techniques.

The Use of CFD for Flow Analysis and Performance Prediction of Centrifugal Pumps

This paper presents some user experience in using the commercial CFD code Fluent for pump flow field calculations. It demonstrates the use of the code with respect to simulating the flow within an industrial centrifugal pump and predicting the corresponding head-capacity curve. Throughout the paper, the CFD model of the selected pump is discussed. The pump with backward curved blades is modeled and meshed with unstructured grid. Quasi-steady calculations utilizing the k-ε turbulence model and the multi reference frame technique are performed for the design point as well as for a range of volume rates with a deviation of 50% from the design value but with similar flow patterns. The data obtained allow the analysis of the main phenomena existent in the pump, such as: pressure changes in the volute for different flow rates; and the incidence at the leading edge of the blade with different flow conditions.

Numerical Investigation of Cavitation of Centrifugal Pump

International Journal of Advance Engineering and Research Development, 2014

New computational methods are continuously developed in order to solve problems in different engineering fiel ds. One of these fields is centrifugal pump, where the challenge is to make centrifugal pump more efficient and to reduce cavitation in the pump. One of the main parts of a centrifugal pump that can be improved is the impeller. In order to optimiz e the centrifugal pump, both experimental and numerical methods are called for. An important topic is here to perform grid sensitivity studies to make sure that the model yields mesh independent results. Another topic of interest is the choice of turbulence model and how this choice affects the grid sensitivity. After this project we made a model that is numerically reliable, mesh independent and fast. This thesis presents a computational study of the flow field generated in centrifugal pump and how that flow field convicts through the impeller. Specifically, the effect that the flow fied acting on the impeller was studied. Data from a modern centrifugal pump manufacturer was used to design a realistic, low speed, large scale efficiency test section. This paper presents the results of computational simulations done in parallel with experimental simulations of the impeller flow field. In comparisons of computational predictions with experimental data, reasonable agreement of the mean flow and generates cavitation in the centrifugal pump. After finding the cavitation area by numerical method, changing the angle of the blade or changing the number of blade the direction of the inlet and outlet flow has been changed.

FLOW SIMULATION AND PERFORMANCE PREDICTION OF CENTRIFUGAL PUMPS USING CFD-TOOL

With the aid of computational fluid dynamics, the complex internal flows in water pump impellers can be well predicted, thus facilitating the product development process of pumps. In this paper a commercial CFD code was used to solve the governing equations of the flow field. A 2-D simulation of turbulent fluid flow is presented to visualize the flow in a centrifugal pump, including the pressure and velocity distributions. The standard k- turbulence model and SIMPLEC algorithm were chosen for turbulence model and pressure-velocity coupling respectively. The simulation was steady and moving reference frame was used to consider the impeller-volute interaction. The head and efficiency at different flow rates are predicted and they agree well with those available in literature for similar pump. From the simulation results it was observed that the flow change has an important effect on the location and area of low pressure region behind the blade inlet and the direction of velocity at impeller inlet. From the study it was observed that FLUENT simulation results give good prediction of performance of centrifugal pump and may help to reduce the required experimental work for the study of centrifugal pump performance.

Performance analysis of cavitating flow in centrifugal pumps using multiphase CFD

Journal of fluids …, 2002

A multi-phase CFD method is used to analyze centrifugal pump performance under developed cavitating conditions. The differential model employed is the homogeneous two-phase Reynolds-Averaged-Navier-Stokes equations, wherein mixture momentum and volume continuity equations are solved along with vapor volume fraction continuity. Mass transfer modeling is provided for the phase change associated with sheet cavitation. Quasi-three-dimensional (Q3D) and fully-three-dimensional analyses are performed for two impeller configurations. Using Q3D analysis, steady and time-dependent analyses were performed across a wide range of flow coefficients and cavitation numbers. Characteristic performance trends associated with offdesign flow and blade cavitation are observed. The rapid drop in head coefficient at low cavitation numbers (breakdown) is captured for all flow coefficients. Local flow field solution plots elucidate the principal physical mechanisms associated with the onset of breakdown. Results are also presented which illustrate the full three dimensional capability of the method.

Design and CFD Analysis of Centrifugal Pump

International Journal for Research in Applied Science & Engineering Technology (IJRASET), 2022

The purpose of this report is to identify /observe and determine the pattern of velocity profile and pressure distribution by using CFD simulation program after the 3D design and modeling of the pump is made using Vista CPD. We have also created a Solid model using Fusion 360 to get a clear idea of Centrifugal pump design. Basically, this report revolves around the idea of investigating the effect and distribution of velocity profile and pressure within a pump having the following specification, Head = 20 m, Flow rate = 100 m 3 /hr, and RPM = 2000. 3D Navier-Stokes equations were solved using ANSYS CFX. The standard k −εturbulence model was chosen for the turbulence model. From the design point of view, we have studied the effects of different parameters like rotational speed, volume flow rate etc on the impeller and volute. From the simulation results it was observed that the pressure increases gradually from impeller inlet to outlet. The static pressure on the pressure side is evidently larger than that on the suction side at the same impeller radius. In addition to this, it was observed that the velocity increases from the impeller inlet until it enters the volute casing. It then drops to a minimum value at the outlet region.

Numerical and experimental investigation of cavitation flows in multistage centrifugal pump_JMST_2018.pdf

Journal of Mechanical Science and Technology, 2018

omena of pumps by Computational fluid dynamics (CFD). In order to accurately ascertain cavitation behavior, a comparison between CFD and experimental data is a significant and essential process. The purpose of this study is to analyze cavitating behavior in multistage centrifugal pumps numerically and experimentally. For this investigation an experimental set up was used to obtain cavitation performance results. The CFD method was used to investigate the multistage centrifugal pump performance under developed cavitating conditions. The Reynolds-averaged Navier-Stokes (RANS) equations were discretized by the finite volume method. The two-equation SST turbulence model was adopted to account for turbulent flows. Numerical data were validated with experimental data and a good comparison of results was achieved. Numerically, cavitation performances were obtained for different pump stages and the effects on cavitation were described according to different NPSH (Net positive suction head). The occurrence of cavitation was also described according to NPSH3% in the head drop lines and water vapor volume fraction on the impeller blade. The rapid drop in head at low NPSH was captured for different flow conditions. It was found that for stage to stage performance, the head drop changes could be related to losses inside the pump. It was also shown that the simulation results can truly represent the development of the attached sheet cavitation in the impeller.

IJERT-Design and CFD Analysis of Centrifugal Pump

International Journal of Engineering Research and Technology (IJERT), 2021

https://www.ijert.org/design-and-cfd-analysis-of-centrifugal-pump https://www.ijert.org/research/design-and-cfd-analysis-of-centrifugal-pump-IJERTCONV9IS10007.pdf Centrifugal pumps are a most commonly used in different fields like industries, agriculture and domestic applications. Computational Fluid Dynamics is most commonly used tool for simulation and analysis. 3-D numerical CFD tool is used for simulation of the flow field characteristics inside the turbo machinery. CFD simulation makes it possible to visualize the flow condition inside centrifugal pump. The present paper describes the head, power, efficiency and to evaluate the pump performance using the ANSYS FLUENT, a computational fluid dynamics simulation tool. These simulations of centrifugal pumps are strongly related to flow rate and pressure drop, which may occur in either the rotating runnerimpeller or the stationary parts of the centrifugal pumps. The numerical simulation can be used to detect the performance of centrifugal pump and to get safe range of operating at different flow rate and rotating speeds. Top view and front view of centrifugal pump